7
Network Working Group C. Rigney
8
Request for Comments: 2865 S. Willens
9
Obsoletes: 2138 Livingston
10
Category: Standards Track A. Rubens
17
Remote Authentication Dial In User Service (RADIUS)
21
This document specifies an Internet standards track protocol for the
22
Internet community, and requests discussion and suggestions for
23
improvements. Please refer to the current edition of the "Internet
24
Official Protocol Standards" (STD 1) for the standardization state
25
and status of this protocol. Distribution of this memo is unlimited.
29
Copyright (C) The Internet Society (2000). All Rights Reserved.
33
This protocol is widely implemented and used. Experience has shown
34
that it can suffer degraded performance and lost data when used in
35
large scale systems, in part because it does not include provisions
36
for congestion control. Readers of this document may find it
37
beneficial to track the progress of the IETF's AAA working group,
38
which may develop a successor protocol that better addresses the
39
scaling and congestion control issues.
43
This document describes a protocol for carrying authentication,
44
authorization, and configuration information between a Network Access
45
Server which desires to authenticate its links and a shared
46
Authentication Server.
50
This memo documents the RADIUS protocol. The early deployment of
51
RADIUS was done using UDP port number 1645, which conflicts with the
52
"datametrics" service. The officially assigned port number for
58
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RFC 2865 RADIUS June 2000
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1. Introduction .......................................... 3
66
1.1 Specification of Requirements ................... 4
67
1.2 Terminology ..................................... 5
68
2. Operation ............................................. 5
69
2.1 Challenge/Response .............................. 7
70
2.2 Interoperation with PAP and CHAP ................ 8
71
2.3 Proxy ........................................... 8
72
2.4 Why UDP? ........................................ 11
73
2.5 Retransmission Hints ............................ 12
74
2.6 Keep-Alives Considered Harmful .................. 13
75
3. Packet Format ......................................... 13
76
4. Packet Types .......................................... 17
77
4.1 Access-Request .................................. 17
78
4.2 Access-Accept ................................... 18
79
4.3 Access-Reject ................................... 20
80
4.4 Access-Challenge ................................ 21
81
5. Attributes ............................................ 22
82
5.1 User-Name ....................................... 26
83
5.2 User-Password ................................... 27
84
5.3 CHAP-Password ................................... 28
85
5.4 NAS-IP-Address .................................. 29
86
5.5 NAS-Port ........................................ 30
87
5.6 Service-Type .................................... 31
88
5.7 Framed-Protocol ................................. 33
89
5.8 Framed-IP-Address ............................... 34
90
5.9 Framed-IP-Netmask ............................... 34
91
5.10 Framed-Routing .................................. 35
92
5.11 Filter-Id ....................................... 36
93
5.12 Framed-MTU ...................................... 37
94
5.13 Framed-Compression .............................. 37
95
5.14 Login-IP-Host ................................... 38
96
5.15 Login-Service ................................... 39
97
5.16 Login-TCP-Port .................................. 40
98
5.17 (unassigned) .................................... 41
99
5.18 Reply-Message ................................... 41
100
5.19 Callback-Number ................................. 42
101
5.20 Callback-Id ..................................... 42
102
5.21 (unassigned) .................................... 43
103
5.22 Framed-Route .................................... 43
104
5.23 Framed-IPX-Network .............................. 44
105
5.24 State ........................................... 45
106
5.25 Class ........................................... 46
107
5.26 Vendor-Specific ................................. 47
108
5.27 Session-Timeout ................................. 48
109
5.28 Idle-Timeout .................................... 49
110
5.29 Termination-Action .............................. 49
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5.30 Called-Station-Id ............................... 50
120
5.31 Calling-Station-Id .............................. 51
121
5.32 NAS-Identifier .................................. 52
122
5.33 Proxy-State ..................................... 53
123
5.34 Login-LAT-Service ............................... 54
124
5.35 Login-LAT-Node .................................. 55
125
5.36 Login-LAT-Group ................................. 56
126
5.37 Framed-AppleTalk-Link ........................... 57
127
5.38 Framed-AppleTalk-Network ........................ 58
128
5.39 Framed-AppleTalk-Zone ........................... 58
129
5.40 CHAP-Challenge .................................. 59
130
5.41 NAS-Port-Type ................................... 60
131
5.42 Port-Limit ...................................... 61
132
5.43 Login-LAT-Port .................................. 62
133
5.44 Table of Attributes ............................. 63
134
6. IANA Considerations ................................... 64
135
6.1 Definition of Terms ............................. 64
136
6.2 Recommended Registration Policies ............... 65
137
7. Examples .............................................. 66
138
7.1 User Telnet to Specified Host ................... 66
139
7.2 Framed User Authenticating with CHAP ............ 67
140
7.3 User with Challenge-Response card ............... 68
141
8. Security Considerations ............................... 71
142
9. Change Log ............................................ 71
143
10. References ............................................ 73
144
11. Acknowledgements ...................................... 74
145
12. Chair's Address ....................................... 74
146
13. Authors' Addresses .................................... 75
147
14. Full Copyright Statement .............................. 76
151
This document obsoletes RFC 2138 [1]. A summary of the changes
152
between this document and RFC 2138 is available in the "Change Log"
155
Managing dispersed serial line and modem pools for large numbers of
156
users can create the need for significant administrative support.
157
Since modem pools are by definition a link to the outside world, they
158
require careful attention to security, authorization and accounting.
159
This can be best achieved by managing a single "database" of users,
160
which allows for authentication (verifying user name and password) as
161
well as configuration information detailing the type of service to
162
deliver to the user (for example, SLIP, PPP, telnet, rlogin).
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Key features of RADIUS are:
179
A Network Access Server (NAS) operates as a client of RADIUS. The
180
client is responsible for passing user information to designated
181
RADIUS servers, and then acting on the response which is returned.
183
RADIUS servers are responsible for receiving user connection
184
requests, authenticating the user, and then returning all
185
configuration information necessary for the client to deliver
188
A RADIUS server can act as a proxy client to other RADIUS servers
189
or other kinds of authentication servers.
193
Transactions between the client and RADIUS server are
194
authenticated through the use of a shared secret, which is never
195
sent over the network. In addition, any user passwords are sent
196
encrypted between the client and RADIUS server, to eliminate the
197
possibility that someone snooping on an unsecure network could
198
determine a user's password.
200
Flexible Authentication Mechanisms
202
The RADIUS server can support a variety of methods to authenticate
203
a user. When it is provided with the user name and original
204
password given by the user, it can support PPP PAP or CHAP, UNIX
205
login, and other authentication mechanisms.
209
All transactions are comprised of variable length Attribute-
210
Length-Value 3-tuples. New attribute values can be added without
211
disturbing existing implementations of the protocol.
213
1.1. Specification of Requirements
215
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
216
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
217
document are to be interpreted as described in BCP 14 [2]. These key
218
words mean the same thing whether capitalized or not.
220
An implementation is not compliant if it fails to satisfy one or more
221
of the must or must not requirements for the protocols it implements.
222
An implementation that satisfies all the must, must not, should and
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should not requirements for its protocols is said to be
232
"unconditionally compliant"; one that satisfies all the must and must
233
not requirements but not all the should or should not requirements
234
for its protocols is said to be "conditionally compliant".
236
A NAS that does not implement a given service MUST NOT implement the
237
RADIUS attributes for that service. For example, a NAS that is
238
unable to offer ARAP service MUST NOT implement the RADIUS attributes
239
for ARAP. A NAS MUST treat a RADIUS access-accept authorizing an
240
unavailable service as an access-reject instead.
244
This document frequently uses the following terms:
246
service The NAS provides a service to the dial-in user, such as PPP
249
session Each service provided by the NAS to a dial-in user
250
constitutes a session, with the beginning of the session
251
defined as the point where service is first provided and
252
the end of the session defined as the point where service
253
is ended. A user may have multiple sessions in parallel or
254
series if the NAS supports that.
257
This means the implementation discards the packet without
258
further processing. The implementation SHOULD provide the
259
capability of logging the error, including the contents of
260
the silently discarded packet, and SHOULD record the event
261
in a statistics counter.
265
When a client is configured to use RADIUS, any user of the client
266
presents authentication information to the client. This might be
267
with a customizable login prompt, where the user is expected to enter
268
their username and password. Alternatively, the user might use a
269
link framing protocol such as the Point-to-Point Protocol (PPP),
270
which has authentication packets which carry this information.
272
Once the client has obtained such information, it may choose to
273
authenticate using RADIUS. To do so, the client creates an "Access-
274
Request" containing such Attributes as the user's name, the user's
275
password, the ID of the client and the Port ID which the user is
276
accessing. When a password is present, it is hidden using a method
277
based on the RSA Message Digest Algorithm MD5 [3].
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RFC 2865 RADIUS June 2000
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The Access-Request is submitted to the RADIUS server via the network.
288
If no response is returned within a length of time, the request is
289
re-sent a number of times. The client can also forward requests to
290
an alternate server or servers in the event that the primary server
291
is down or unreachable. An alternate server can be used either after
292
a number of tries to the primary server fail, or in a round-robin
293
fashion. Retry and fallback algorithms are the topic of current
294
research and are not specified in detail in this document.
296
Once the RADIUS server receives the request, it validates the sending
297
client. A request from a client for which the RADIUS server does not
298
have a shared secret MUST be silently discarded. If the client is
299
valid, the RADIUS server consults a database of users to find the
300
user whose name matches the request. The user entry in the database
301
contains a list of requirements which must be met to allow access for
302
the user. This always includes verification of the password, but can
303
also specify the client(s) or port(s) to which the user is allowed
306
The RADIUS server MAY make requests of other servers in order to
307
satisfy the request, in which case it acts as a client.
309
If any Proxy-State attributes were present in the Access-Request,
310
they MUST be copied unmodified and in order into the response packet.
311
Other Attributes can be placed before, after, or even between the
312
Proxy-State attributes.
314
If any condition is not met, the RADIUS server sends an "Access-
315
Reject" response indicating that this user request is invalid. If
316
desired, the server MAY include a text message in the Access-Reject
317
which MAY be displayed by the client to the user. No other
318
Attributes (except Proxy-State) are permitted in an Access-Reject.
320
If all conditions are met and the RADIUS server wishes to issue a
321
challenge to which the user must respond, the RADIUS server sends an
322
"Access-Challenge" response. It MAY include a text message to be
323
displayed by the client to the user prompting for a response to the
324
challenge, and MAY include a State attribute.
326
If the client receives an Access-Challenge and supports
327
challenge/response it MAY display the text message, if any, to the
328
user, and then prompt the user for a response. The client then re-
329
submits its original Access-Request with a new request ID, with the
330
User-Password Attribute replaced by the response (encrypted), and
331
including the State Attribute from the Access-Challenge, if any.
332
Only 0 or 1 instances of the State Attribute SHOULD be
338
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present in a request. The server can respond to this new Access-
344
Request with either an Access-Accept, an Access-Reject, or another
347
If all conditions are met, the list of configuration values for the
348
user are placed into an "Access-Accept" response. These values
349
include the type of service (for example: SLIP, PPP, Login User) and
350
all necessary values to deliver the desired service. For SLIP and
351
PPP, this may include values such as IP address, subnet mask, MTU,
352
desired compression, and desired packet filter identifiers. For
353
character mode users, this may include values such as desired
356
2.1. Challenge/Response
358
In challenge/response authentication, the user is given an
359
unpredictable number and challenged to encrypt it and give back the
360
result. Authorized users are equipped with special devices such as
361
smart cards or software that facilitate calculation of the correct
362
response with ease. Unauthorized users, lacking the appropriate
363
device or software and lacking knowledge of the secret key necessary
364
to emulate such a device or software, can only guess at the response.
366
The Access-Challenge packet typically contains a Reply-Message
367
including a challenge to be displayed to the user, such as a numeric
368
value unlikely ever to be repeated. Typically this is obtained from
369
an external server that knows what type of authenticator is in the
370
possession of the authorized user and can therefore choose a random
371
or non-repeating pseudorandom number of an appropriate radix and
374
The user then enters the challenge into his device (or software) and
375
it calculates a response, which the user enters into the client which
376
forwards it to the RADIUS server via a second Access-Request. If the
377
response matches the expected response the RADIUS server replies with
378
an Access-Accept, otherwise an Access-Reject.
380
Example: The NAS sends an Access-Request packet to the RADIUS Server
381
with NAS-Identifier, NAS-Port, User-Name, User-Password (which may
382
just be a fixed string like "challenge" or ignored). The server
383
sends back an Access-Challenge packet with State and a Reply-Message
384
along the lines of "Challenge 12345678, enter your response at the
385
prompt" which the NAS displays. The NAS prompts for the response and
386
sends a NEW Access-Request to the server (with a new ID) with NAS-
387
Identifier, NAS-Port, User-Name, User-Password (the response just
388
entered by the user, encrypted), and the same State Attribute that
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came with the Access-Challenge. The server then sends back either an
400
Access-Accept or Access-Reject based on whether the response matches
401
the required value, or it can even send another Access-Challenge.
403
2.2. Interoperation with PAP and CHAP
405
For PAP, the NAS takes the PAP ID and password and sends them in an
406
Access-Request packet as the User-Name and User-Password. The NAS MAY
407
include the Attributes Service-Type = Framed-User and Framed-Protocol
408
= PPP as a hint to the RADIUS server that PPP service is expected.
410
For CHAP, the NAS generates a random challenge (preferably 16 octets)
411
and sends it to the user, who returns a CHAP response along with a
412
CHAP ID and CHAP username. The NAS then sends an Access-Request
413
packet to the RADIUS server with the CHAP username as the User-Name
414
and with the CHAP ID and CHAP response as the CHAP-Password
415
(Attribute 3). The random challenge can either be included in the
416
CHAP-Challenge attribute or, if it is 16 octets long, it can be
417
placed in the Request Authenticator field of the Access-Request
418
packet. The NAS MAY include the Attributes Service-Type = Framed-
419
User and Framed-Protocol = PPP as a hint to the RADIUS server that
420
PPP service is expected.
422
The RADIUS server looks up a password based on the User-Name,
423
encrypts the challenge using MD5 on the CHAP ID octet, that password,
424
and the CHAP challenge (from the CHAP-Challenge attribute if present,
425
otherwise from the Request Authenticator), and compares that result
426
to the CHAP-Password. If they match, the server sends back an
427
Access-Accept, otherwise it sends back an Access-Reject.
429
If the RADIUS server is unable to perform the requested
430
authentication it MUST return an Access-Reject. For example, CHAP
431
requires that the user's password be available in cleartext to the
432
server so that it can encrypt the CHAP challenge and compare that to
433
the CHAP response. If the password is not available in cleartext to
434
the RADIUS server then the server MUST send an Access-Reject to the
439
With proxy RADIUS, one RADIUS server receives an authentication (or
440
accounting) request from a RADIUS client (such as a NAS), forwards
441
the request to a remote RADIUS server, receives the reply from the
442
remote server, and sends that reply to the client, possibly with
443
changes to reflect local administrative policy. A common use for
444
proxy RADIUS is roaming. Roaming permits two or more administrative
445
entities to allow each other's users to dial in to either entity's
450
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RFC 2865 RADIUS June 2000
455
The NAS sends its RADIUS access-request to the "forwarding server"
456
which forwards it to the "remote server". The remote server sends a
457
response (Access-Accept, Access-Reject, or Access-Challenge) back to
458
the forwarding server, which sends it back to the NAS. The User-Name
459
attribute MAY contain a Network Access Identifier [8] for RADIUS
460
Proxy operations. The choice of which server receives the forwarded
461
request SHOULD be based on the authentication "realm". The
462
authentication realm MAY be the realm part of a Network Access
463
Identifier (a "named realm"). Alternatively, the choice of which
464
server receives the forwarded request MAY be based on whatever other
465
criteria the forwarding server is configured to use, such as Called-
466
Station-Id (a "numbered realm").
468
A RADIUS server can function as both a forwarding server and a remote
469
server, serving as a forwarding server for some realms and a remote
470
server for other realms. One forwarding server can act as a
471
forwarder for any number of remote servers. A remote server can have
472
any number of servers forwarding to it and can provide authentication
473
for any number of realms. One forwarding server can forward to
474
another forwarding server to create a chain of proxies, although care
475
must be taken to avoid introducing loops.
477
The following scenario illustrates a proxy RADIUS communication
478
between a NAS and the forwarding and remote RADIUS servers:
480
1. A NAS sends its access-request to the forwarding server.
482
2. The forwarding server forwards the access-request to the remote
485
3. The remote server sends an access-accept, access-reject or
486
access-challenge back to the forwarding server. For this example,
487
an access-accept is sent.
489
4. The forwarding server sends the access-accept to the NAS.
491
The forwarding server MUST treat any Proxy-State attributes already
492
in the packet as opaque data. Its operation MUST NOT depend on the
493
content of Proxy-State attributes added by previous servers.
495
If there are any Proxy-State attributes in the request received from
496
the client, the forwarding server MUST include those Proxy-State
497
attributes in its reply to the client. The forwarding server MAY
498
include the Proxy-State attributes in the access-request when it
499
forwards the request, or MAY omit them in the forwarded request. If
500
the forwarding server omits the Proxy-State attributes in the
501
forwarded access-request, it MUST attach them to the response before
502
sending it to the client.
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511
We now examine each step in more detail.
513
1. A NAS sends its access-request to the forwarding server. The
514
forwarding server decrypts the User-Password, if present, using
515
the shared secret it knows for the NAS. If a CHAP-Password
516
attribute is present in the packet and no CHAP-Challenge attribute
517
is present, the forwarding server MUST leave the Request-
518
Authenticator untouched or copy it to a CHAP-Challenge attribute.
520
'' The forwarding server MAY add one Proxy-State attribute to the
521
packet. (It MUST NOT add more than one.) If it adds a Proxy-
522
State, the Proxy-State MUST appear after any other Proxy-States in
523
the packet. The forwarding server MUST NOT modify any other
524
Proxy-States that were in the packet (it may choose not to forward
525
them, but it MUST NOT change their contents). The forwarding
526
server MUST NOT change the order of any attributes of the same
527
type, including Proxy-State.
529
2. The forwarding server encrypts the User-Password, if present,
530
using the secret it shares with the remote server, sets the
531
Identifier as needed, and forwards the access-request to the
534
3. The remote server (if the final destination) verifies the user
535
using User-Password, CHAP-Password, or such method as future
536
extensions may dictate, and returns an access-accept, access-
537
reject or access-challenge back to the forwarding server. For
538
this example, an access-accept is sent. The remote server MUST
539
copy all Proxy-State attributes (and only the Proxy-State
540
attributes) in order from the access-request to the response
541
packet, without modifying them.
543
4. The forwarding server verifies the Response Authenticator using
544
the secret it shares with the remote server, and silently discards
545
the packet if it fails verification. If the packet passes
546
verification, the forwarding server removes the last Proxy-State
547
(if it attached one), signs the Response Authenticator using the
548
secret it shares with the NAS, restores the Identifier to match
549
the one in the original request by the NAS, and sends the access-
552
A forwarding server MAY need to modify attributes to enforce local
553
policy. Such policy is outside the scope of this document, with the
554
following restrictions. A forwarding server MUST not modify existing
555
Proxy-State, State, or Class attributes present in the packet.
562
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567
Implementers of forwarding servers should consider carefully which
568
values it is willing to accept for Service-Type. Careful
569
consideration must be given to the effects of passing along Service-
570
Types of NAS-Prompt or Administrative in a proxied Access-Accept, and
571
implementers may wish to provide mechanisms to block those or other
572
service types, or other attributes. Such mechanisms are outside the
573
scope of this document.
577
A frequently asked question is why RADIUS uses UDP instead of TCP as
578
a transport protocol. UDP was chosen for strictly technical reasons.
580
There are a number of issues which must be understood. RADIUS is a
581
transaction based protocol which has several interesting
584
1. If the request to a primary Authentication server fails, a
585
secondary server must be queried.
587
To meet this requirement, a copy of the request must be kept above
588
the transport layer to allow for alternate transmission. This
589
means that retransmission timers are still required.
591
2. The timing requirements of this particular protocol are
592
significantly different than TCP provides.
594
At one extreme, RADIUS does not require a "responsive" detection
595
of lost data. The user is willing to wait several seconds for the
596
authentication to complete. The generally aggressive TCP
597
retransmission (based on average round trip time) is not required,
598
nor is the acknowledgement overhead of TCP.
600
At the other extreme, the user is not willing to wait several
601
minutes for authentication. Therefore the reliable delivery of
602
TCP data two minutes later is not useful. The faster use of an
603
alternate server allows the user to gain access before giving up.
605
3. The stateless nature of this protocol simplifies the use of UDP.
607
Clients and servers come and go. Systems are rebooted, or are
608
power cycled independently. Generally this does not cause a
609
problem and with creative timeouts and detection of lost TCP
610
connections, code can be written to handle anomalous events. UDP
611
however completely eliminates any of this special handling. Each
612
client and server can open their UDP transport just once and leave
613
it open through all types of failure events on the network.
618
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623
4. UDP simplifies the server implementation.
625
In the earliest implementations of RADIUS, the server was single
626
threaded. This means that a single request was received,
627
processed, and returned. This was found to be unmanageable in
628
environments where the back-end security mechanism took real time
629
(1 or more seconds). The server request queue would fill and in
630
environments where hundreds of people were being authenticated
631
every minute, the request turn-around time increased to longer
632
than users were willing to wait (this was especially severe when a
633
specific lookup in a database or over DNS took 30 or more
634
seconds). The obvious solution was to make the server multi-
635
threaded. Achieving this was simple with UDP. Separate processes
636
were spawned to serve each request and these processes could
637
respond directly to the client NAS with a simple UDP packet to the
638
original transport of the client.
640
It's not all a panacea. As noted, using UDP requires one thing which
641
is built into TCP: with UDP we must artificially manage
642
retransmission timers to the same server, although they don't require
643
the same attention to timing provided by TCP. This one penalty is a
644
small price to pay for the advantages of UDP in this protocol.
646
Without TCP we would still probably be using tin cans connected by
647
string. But for this particular protocol, UDP is a better choice.
649
2.5. Retransmission Hints
651
If the RADIUS server and alternate RADIUS server share the same
652
shared secret, it is OK to retransmit the packet to the alternate
653
RADIUS server with the same ID and Request Authenticator, because the
654
content of the attributes haven't changed. If you want to use a new
655
Request Authenticator when sending to the alternate server, you may.
657
If you change the contents of the User-Password attribute (or any
658
other attribute), you need a new Request Authenticator and therefore
661
If the NAS is retransmitting a RADIUS request to the same server as
662
before, and the attributes haven't changed, you MUST use the same
663
Request Authenticator, ID, and source port. If any attributes have
664
changed, you MUST use a new Request Authenticator and ID.
666
A NAS MAY use the same ID across all servers, or MAY keep track of
667
IDs separately for each server, it is up to the implementer. If a
668
NAS needs more than 256 IDs for outstanding requests, it MAY use
674
Rigney, et al. Standards Track [Page 12]
676
RFC 2865 RADIUS June 2000
679
additional source ports to send requests from, and keep track of IDs
680
for each source port. This allows up to 16 million or so outstanding
681
requests at one time to a single server.
683
2.6. Keep-Alives Considered Harmful
685
Some implementers have adopted the practice of sending test RADIUS
686
requests to see if a server is alive. This practice is strongly
687
discouraged, since it adds to load and harms scalability without
688
providing any additional useful information. Since a RADIUS request
689
is contained in a single datagram, in the time it would take you to
690
send a ping you could just send the RADIUS request, and getting a
691
reply tells you that the RADIUS server is up. If you do not have a
692
RADIUS request to send, it does not matter if the server is up or
693
not, because you are not using it.
695
If you want to monitor your RADIUS server, use SNMP. That's what
700
Exactly one RADIUS packet is encapsulated in the UDP Data field [4],
701
where the UDP Destination Port field indicates 1812 (decimal).
703
When a reply is generated, the source and destination ports are
706
This memo documents the RADIUS protocol. The early deployment of
707
RADIUS was done using UDP port number 1645, which conflicts with the
708
"datametrics" service. The officially assigned port number for
730
Rigney, et al. Standards Track [Page 13]
732
RFC 2865 RADIUS June 2000
735
A summary of the RADIUS data format is shown below. The fields are
736
transmitted from left to right.
739
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
740
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
741
| Code | Identifier | Length |
742
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
747
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
749
+-+-+-+-+-+-+-+-+-+-+-+-+-
753
The Code field is one octet, and identifies the type of RADIUS
754
packet. When a packet is received with an invalid Code field, it
755
is silently discarded.
757
RADIUS Codes (decimal) are assigned as follows:
763
5 Accounting-Response
765
12 Status-Server (experimental)
766
13 Status-Client (experimental)
769
Codes 4 and 5 are covered in the RADIUS Accounting document [5].
770
Codes 12 and 13 are reserved for possible use, but are not further
775
The Identifier field is one octet, and aids in matching requests
776
and replies. The RADIUS server can detect a duplicate request if
777
it has the same client source IP address and source UDP port and
778
Identifier within a short span of time.
786
Rigney, et al. Standards Track [Page 14]
788
RFC 2865 RADIUS June 2000
793
The Length field is two octets. It indicates the length of the
794
packet including the Code, Identifier, Length, Authenticator and
795
Attribute fields. Octets outside the range of the Length field
796
MUST be treated as padding and ignored on reception. If the
797
packet is shorter than the Length field indicates, it MUST be
798
silently discarded. The minimum length is 20 and maximum length
803
The Authenticator field is sixteen (16) octets. The most
804
significant octet is transmitted first. This value is used to
805
authenticate the reply from the RADIUS server, and is used in the
806
password hiding algorithm.
808
Request Authenticator
810
In Access-Request Packets, the Authenticator value is a 16
811
octet random number, called the Request Authenticator. The
812
value SHOULD be unpredictable and unique over the lifetime of a
813
secret (the password shared between the client and the RADIUS
814
server), since repetition of a request value in conjunction
815
with the same secret would permit an attacker to reply with a
816
previously intercepted response. Since it is expected that the
817
same secret MAY be used to authenticate with servers in
818
disparate geographic regions, the Request Authenticator field
819
SHOULD exhibit global and temporal uniqueness.
821
The Request Authenticator value in an Access-Request packet
822
SHOULD also be unpredictable, lest an attacker trick a server
823
into responding to a predicted future request, and then use the
824
response to masquerade as that server to a future Access-
827
Although protocols such as RADIUS are incapable of protecting
828
against theft of an authenticated session via realtime active
829
wiretapping attacks, generation of unique unpredictable
830
requests can protect against a wide range of active attacks
831
against authentication.
833
The NAS and RADIUS server share a secret. That shared secret
834
followed by the Request Authenticator is put through a one-way
835
MD5 hash to create a 16 octet digest value which is xored with
836
the password entered by the user, and the xored result placed
842
Rigney, et al. Standards Track [Page 15]
844
RFC 2865 RADIUS June 2000
847
in the User-Password attribute in the Access-Request packet.
848
See the entry for User-Password in the section on Attributes
849
for a more detailed description.
851
Response Authenticator
853
The value of the Authenticator field in Access-Accept, Access-
854
Reject, and Access-Challenge packets is called the Response
855
Authenticator, and contains a one-way MD5 hash calculated over
856
a stream of octets consisting of: the RADIUS packet, beginning
857
with the Code field, including the Identifier, the Length, the
858
Request Authenticator field from the Access-Request packet, and
859
the response Attributes, followed by the shared secret. That
861
MD5(Code+ID+Length+RequestAuth+Attributes+Secret) where +
862
denotes concatenation.
866
The secret (password shared between the client and the RADIUS
867
server) SHOULD be at least as large and unguessable as a well-
868
chosen password. It is preferred that the secret be at least 16
869
octets. This is to ensure a sufficiently large range for the
870
secret to provide protection against exhaustive search attacks.
871
The secret MUST NOT be empty (length 0) since this would allow
872
packets to be trivially forged.
874
A RADIUS server MUST use the source IP address of the RADIUS UDP
875
packet to decide which shared secret to use, so that RADIUS
876
requests can be proxied.
878
When using a forwarding proxy, the proxy must be able to alter the
879
packet as it passes through in each direction - when the proxy
880
forwards the request, the proxy MAY add a Proxy-State Attribute,
881
and when the proxy forwards a response, it MUST remove its Proxy-
882
State Attribute if it added one. Proxy-State is always added or
883
removed after any other Proxy-States, but no other assumptions
884
regarding its location within the list of attributes can be made.
885
Since Access-Accept and Access-Reject replies are authenticated on
886
the entire packet contents, the stripping of the Proxy-State
887
attribute invalidates the signature in the packet - so the proxy
890
Further details of RADIUS proxy implementation are outside the
891
scope of this document.
898
Rigney, et al. Standards Track [Page 16]
900
RFC 2865 RADIUS June 2000
905
The RADIUS Packet type is determined by the Code field in the first
912
Access-Request packets are sent to a RADIUS server, and convey
913
information used to determine whether a user is allowed access to
914
a specific NAS, and any special services requested for that user.
915
An implementation wishing to authenticate a user MUST transmit a
916
RADIUS packet with the Code field set to 1 (Access-Request).
918
Upon receipt of an Access-Request from a valid client, an
919
appropriate reply MUST be transmitted.
921
An Access-Request SHOULD contain a User-Name attribute. It MUST
922
contain either a NAS-IP-Address attribute or a NAS-Identifier
925
An Access-Request MUST contain either a User-Password or a CHAP-
926
Password or a State. An Access-Request MUST NOT contain both a
927
User-Password and a CHAP-Password. If future extensions allow
928
other kinds of authentication information to be conveyed, the
929
attribute for that can be used in an Access-Request instead of
930
User-Password or CHAP-Password.
932
An Access-Request SHOULD contain a NAS-Port or NAS-Port-Type
933
attribute or both unless the type of access being requested does
934
not involve a port or the NAS does not distinguish among its
937
An Access-Request MAY contain additional attributes as a hint to
938
the server, but the server is not required to honor the hint.
940
When a User-Password is present, it is hidden using a method based
941
on the RSA Message Digest Algorithm MD5 [3].
954
Rigney, et al. Standards Track [Page 17]
956
RFC 2865 RADIUS June 2000
959
A summary of the Access-Request packet format is shown below. The
960
fields are transmitted from left to right.
963
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
964
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
965
| Code | Identifier | Length |
966
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
968
| Request Authenticator |
971
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
973
+-+-+-+-+-+-+-+-+-+-+-+-+-
977
1 for Access-Request.
981
The Identifier field MUST be changed whenever the content of the
982
Attributes field changes, and whenever a valid reply has been
983
received for a previous request. For retransmissions, the
984
Identifier MUST remain unchanged.
986
Request Authenticator
988
The Request Authenticator value MUST be changed each time a new
993
The Attribute field is variable in length, and contains the list
994
of Attributes that are required for the type of service, as well
995
as any desired optional Attributes.
1001
Access-Accept packets are sent by the RADIUS server, and provide
1002
specific configuration information necessary to begin delivery of
1003
service to the user. If all Attribute values received in an
1004
Access-Request are acceptable then the RADIUS implementation MUST
1005
transmit a packet with the Code field set to 2 (Access-Accept).
1010
Rigney, et al. Standards Track [Page 18]
1012
RFC 2865 RADIUS June 2000
1015
On reception of an Access-Accept, the Identifier field is matched
1016
with a pending Access-Request. The Response Authenticator field
1017
MUST contain the correct response for the pending Access-Request.
1018
Invalid packets are silently discarded.
1020
A summary of the Access-Accept packet format is shown below. The
1021
fields are transmitted from left to right.
1024
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1025
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1026
| Code | Identifier | Length |
1027
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1029
| Response Authenticator |
1032
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1034
+-+-+-+-+-+-+-+-+-+-+-+-+-
1038
2 for Access-Accept.
1042
The Identifier field is a copy of the Identifier field of the
1043
Access-Request which caused this Access-Accept.
1045
Response Authenticator
1047
The Response Authenticator value is calculated from the Access-
1048
Request value, as described earlier.
1052
The Attribute field is variable in length, and contains a list of
1053
zero or more Attributes.
1066
Rigney, et al. Standards Track [Page 19]
1068
RFC 2865 RADIUS June 2000
1075
If any value of the received Attributes is not acceptable, then
1076
the RADIUS server MUST transmit a packet with the Code field set
1077
to 3 (Access-Reject). It MAY include one or more Reply-Message
1078
Attributes with a text message which the NAS MAY display to the
1081
A summary of the Access-Reject packet format is shown below. The
1082
fields are transmitted from left to right.
1085
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1086
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1087
| Code | Identifier | Length |
1088
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1090
| Response Authenticator |
1093
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1095
+-+-+-+-+-+-+-+-+-+-+-+-+-
1099
3 for Access-Reject.
1103
The Identifier field is a copy of the Identifier field of the
1104
Access-Request which caused this Access-Reject.
1106
Response Authenticator
1108
The Response Authenticator value is calculated from the Access-
1109
Request value, as described earlier.
1113
The Attribute field is variable in length, and contains a list of
1114
zero or more Attributes.
1122
Rigney, et al. Standards Track [Page 20]
1124
RFC 2865 RADIUS June 2000
1127
4.4. Access-Challenge
1131
If the RADIUS server desires to send the user a challenge
1132
requiring a response, then the RADIUS server MUST respond to the
1133
Access-Request by transmitting a packet with the Code field set to
1134
11 (Access-Challenge).
1136
The Attributes field MAY have one or more Reply-Message
1137
Attributes, and MAY have a single State Attribute, or none.
1138
Vendor-Specific, Idle-Timeout, Session-Timeout and Proxy-State
1139
attributes MAY also be included. No other Attributes defined in
1140
this document are permitted in an Access-Challenge.
1142
On receipt of an Access-Challenge, the Identifier field is matched
1143
with a pending Access-Request. Additionally, the Response
1144
Authenticator field MUST contain the correct response for the
1145
pending Access-Request. Invalid packets are silently discarded.
1147
If the NAS does not support challenge/response, it MUST treat an
1148
Access-Challenge as though it had received an Access-Reject
1151
If the NAS supports challenge/response, receipt of a valid
1152
Access-Challenge indicates that a new Access-Request SHOULD be
1153
sent. The NAS MAY display the text message, if any, to the user,
1154
and then prompt the user for a response. It then sends its
1155
original Access-Request with a new request ID and Request
1156
Authenticator, with the User-Password Attribute replaced by the
1157
user's response (encrypted), and including the State Attribute
1158
from the Access-Challenge, if any. Only 0 or 1 instances of the
1159
State Attribute can be present in an Access-Request.
1161
A NAS which supports PAP MAY forward the Reply-Message to the
1162
dialing client and accept a PAP response which it can use as
1163
though the user had entered the response. If the NAS cannot do
1164
so, it MUST treat the Access-Challenge as though it had received
1165
an Access-Reject instead.
1178
Rigney, et al. Standards Track [Page 21]
1180
RFC 2865 RADIUS June 2000
1183
A summary of the Access-Challenge packet format is shown below. The
1184
fields are transmitted from left to right.
1187
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1188
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1189
| Code | Identifier | Length |
1190
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1192
| Response Authenticator |
1195
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1197
+-+-+-+-+-+-+-+-+-+-+-+-+-
1201
11 for Access-Challenge.
1205
The Identifier field is a copy of the Identifier field of the
1206
Access-Request which caused this Access-Challenge.
1208
Response Authenticator
1210
The Response Authenticator value is calculated from the Access-
1211
Request value, as described earlier.
1215
The Attributes field is variable in length, and contains a list of
1216
zero or more Attributes.
1220
RADIUS Attributes carry the specific authentication, authorization,
1221
information and configuration details for the request and reply.
1223
The end of the list of Attributes is indicated by the Length of the
1226
Some Attributes MAY be included more than once. The effect of this
1227
is Attribute specific, and is specified in each Attribute
1228
description. A summary table is provided at the end of the
1229
"Attributes" section.
1234
Rigney, et al. Standards Track [Page 22]
1236
RFC 2865 RADIUS June 2000
1239
If multiple Attributes with the same Type are present, the order of
1240
Attributes with the same Type MUST be preserved by any proxies. The
1241
order of Attributes of different Types is not required to be
1242
preserved. A RADIUS server or client MUST NOT have any dependencies
1243
on the order of attributes of different types. A RADIUS server or
1244
client MUST NOT require attributes of the same type to be contiguous.
1246
Where an Attribute's description limits which kinds of packet it can
1247
be contained in, this applies only to the packet types defined in
1248
this document, namely Access-Request, Access-Accept, Access-Reject
1249
and Access-Challenge (Codes 1, 2, 3, and 11). Other documents
1250
defining other packet types may also use Attributes described here.
1251
To determine which Attributes are allowed in Accounting-Request and
1252
Accounting-Response packets (Codes 4 and 5) refer to the RADIUS
1253
Accounting document [5].
1255
Likewise where packet types defined here state that only certain
1256
Attributes are permissible in them, future memos defining new
1257
Attributes should indicate which packet types the new Attributes may
1260
A summary of the Attribute format is shown below. The fields are
1261
transmitted from left to right.
1264
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
1265
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1266
| Type | Length | Value ...
1267
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1271
The Type field is one octet. Up-to-date values of the RADIUS Type
1272
field are specified in the most recent "Assigned Numbers" RFC [6].
1273
Values 192-223 are reserved for experimental use, values 224-240
1274
are reserved for implementation-specific use, and values 241-255
1275
are reserved and should not be used.
1277
A RADIUS server MAY ignore Attributes with an unknown Type.
1279
A RADIUS client MAY ignore Attributes with an unknown Type.
1290
Rigney, et al. Standards Track [Page 23]
1292
RFC 2865 RADIUS June 2000
1295
This specification concerns the following values:
1309
13 Framed-Compression
1319
23 Framed-IPX-Network
1325
29 Termination-Action
1326
30 Called-Station-Id
1327
31 Calling-Station-Id
1330
34 Login-LAT-Service
1333
37 Framed-AppleTalk-Link
1334
38 Framed-AppleTalk-Network
1335
39 Framed-AppleTalk-Zone
1336
40-59 (reserved for accounting)
1346
Rigney, et al. Standards Track [Page 24]
1348
RFC 2865 RADIUS June 2000
1353
The Length field is one octet, and indicates the length of this
1354
Attribute including the Type, Length and Value fields. If an
1355
Attribute is received in an Access-Request but with an invalid
1356
Length, an Access-Reject SHOULD be transmitted. If an Attribute
1357
is received in an Access-Accept, Access-Reject or Access-Challenge
1358
packet with an invalid length, the packet MUST either be treated
1359
as an Access-Reject or else silently discarded.
1363
The Value field is zero or more octets and contains information
1364
specific to the Attribute. The format and length of the Value
1365
field is determined by the Type and Length fields.
1367
Note that none of the types in RADIUS terminate with a NUL (hex
1368
00). In particular, types "text" and "string" in RADIUS do not
1369
terminate with a NUL (hex 00). The Attribute has a length field
1370
and does not use a terminator. Text contains UTF-8 encoded 10646
1371
[7] characters and String contains 8-bit binary data. Servers and
1372
servers and clients MUST be able to deal with embedded nulls.
1373
RADIUS implementers using C are cautioned not to use strcpy() when
1376
The format of the value field is one of five data types. Note
1377
that type "text" is a subset of type "string".
1379
text 1-253 octets containing UTF-8 encoded 10646 [7]
1380
characters. Text of length zero (0) MUST NOT be sent;
1381
omit the entire attribute instead.
1383
string 1-253 octets containing binary data (values 0 through
1384
255 decimal, inclusive). Strings of length zero (0)
1385
MUST NOT be sent; omit the entire attribute instead.
1387
address 32 bit value, most significant octet first.
1389
integer 32 bit unsigned value, most significant octet first.
1391
time 32 bit unsigned value, most significant octet first --
1392
seconds since 00:00:00 UTC, January 1, 1970. The
1393
standard Attributes do not use this data type but it is
1394
presented here for possible use in future attributes.
1402
Rigney, et al. Standards Track [Page 25]
1404
RFC 2865 RADIUS June 2000
1411
This Attribute indicates the name of the user to be authenticated.
1412
It MUST be sent in Access-Request packets if available.
1414
It MAY be sent in an Access-Accept packet, in which case the
1415
client SHOULD use the name returned in the Access-Accept packet in
1416
all Accounting-Request packets for this session. If the Access-
1417
Accept includes Service-Type = Rlogin and the User-Name attribute,
1418
a NAS MAY use the returned User-Name when performing the Rlogin
1421
A summary of the User-Name Attribute format is shown below. The
1422
fields are transmitted from left to right.
1425
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1426
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1427
| Type | Length | String ...
1428
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1440
The String field is one or more octets. The NAS may limit the
1441
maximum length of the User-Name but the ability to handle at least
1442
63 octets is recommended.
1444
The format of the username MAY be one of several forms:
1446
text Consisting only of UTF-8 encoded 10646 [7] characters.
1448
network access identifier
1449
A Network Access Identifier as described in RFC 2486
1453
A name in ASN.1 form used in Public Key authentication
1458
Rigney, et al. Standards Track [Page 26]
1460
RFC 2865 RADIUS June 2000
1467
This Attribute indicates the password of the user to be
1468
authenticated, or the user's input following an Access-Challenge.
1469
It is only used in Access-Request packets.
1471
On transmission, the password is hidden. The password is first
1472
padded at the end with nulls to a multiple of 16 octets. A one-
1473
way MD5 hash is calculated over a stream of octets consisting of
1474
the shared secret followed by the Request Authenticator. This
1475
value is XORed with the first 16 octet segment of the password and
1476
placed in the first 16 octets of the String field of the User-
1479
If the password is longer than 16 characters, a second one-way MD5
1480
hash is calculated over a stream of octets consisting of the
1481
shared secret followed by the result of the first xor. That hash
1482
is XORed with the second 16 octet segment of the password and
1483
placed in the second 16 octets of the String field of the User-
1486
If necessary, this operation is repeated, with each xor result
1487
being used along with the shared secret to generate the next hash
1488
to xor the next segment of the password, to no more than 128
1491
The method is taken from the book "Network Security" by Kaufman,
1492
Perlman and Speciner [9] pages 109-110. A more precise
1493
explanation of the method follows:
1495
Call the shared secret S and the pseudo-random 128-bit Request
1496
Authenticator RA. Break the password into 16-octet chunks p1, p2,
1497
etc. with the last one padded at the end with nulls to a 16-octet
1498
boundary. Call the ciphertext blocks c(1), c(2), etc. We'll need
1499
intermediate values b1, b2, etc.
1501
b1 = MD5(S + RA) c(1) = p1 xor b1
1502
b2 = MD5(S + c(1)) c(2) = p2 xor b2
1506
bi = MD5(S + c(i-1)) c(i) = pi xor bi
1508
The String will contain c(1)+c(2)+...+c(i) where + denotes
1514
Rigney, et al. Standards Track [Page 27]
1516
RFC 2865 RADIUS June 2000
1519
On receipt, the process is reversed to yield the original
1522
A summary of the User-Password Attribute format is shown below. The
1523
fields are transmitted from left to right.
1526
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1527
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1528
| Type | Length | String ...
1529
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1533
2 for User-Password.
1537
At least 18 and no larger than 130.
1541
The String field is between 16 and 128 octets long, inclusive.
1547
This Attribute indicates the response value provided by a PPP
1548
Challenge-Handshake Authentication Protocol (CHAP) user in
1549
response to the challenge. It is only used in Access-Request
1552
The CHAP challenge value is found in the CHAP-Challenge Attribute
1553
(60) if present in the packet, otherwise in the Request
1554
Authenticator field.
1556
A summary of the CHAP-Password Attribute format is shown below. The
1557
fields are transmitted from left to right.
1560
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9
1561
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1562
| Type | Length | CHAP Ident | String ...
1563
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1570
Rigney, et al. Standards Track [Page 28]
1572
RFC 2865 RADIUS June 2000
1577
3 for CHAP-Password.
1585
This field is one octet, and contains the CHAP Identifier from the
1586
user's CHAP Response.
1590
The String field is 16 octets, and contains the CHAP Response from
1597
This Attribute indicates the identifying IP Address of the NAS
1598
which is requesting authentication of the user, and SHOULD be
1599
unique to the NAS within the scope of the RADIUS server. NAS-IP-
1600
Address is only used in Access-Request packets. Either NAS-IP-
1601
Address or NAS-Identifier MUST be present in an Access-Request
1604
Note that NAS-IP-Address MUST NOT be used to select the shared
1605
secret used to authenticate the request. The source IP address of
1606
the Access-Request packet MUST be used to select the shared
1609
A summary of the NAS-IP-Address Attribute format is shown below. The
1610
fields are transmitted from left to right.
1613
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1614
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1615
| Type | Length | Address
1616
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1618
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1622
4 for NAS-IP-Address.
1626
Rigney, et al. Standards Track [Page 29]
1628
RFC 2865 RADIUS June 2000
1637
The Address field is four octets.
1643
This Attribute indicates the physical port number of the NAS which
1644
is authenticating the user. It is only used in Access-Request
1645
packets. Note that this is using "port" in its sense of a
1646
physical connection on the NAS, not in the sense of a TCP or UDP
1647
port number. Either NAS-Port or NAS-Port-Type (61) or both SHOULD
1648
be present in an Access-Request packet, if the NAS differentiates
1651
A summary of the NAS-Port Attribute format is shown below. The
1652
fields are transmitted from left to right.
1655
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1656
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1657
| Type | Length | Value
1658
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1660
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1672
The Value field is four octets.
1682
Rigney, et al. Standards Track [Page 30]
1684
RFC 2865 RADIUS June 2000
1691
This Attribute indicates the type of service the user has
1692
requested, or the type of service to be provided. It MAY be used
1693
in both Access-Request and Access-Accept packets. A NAS is not
1694
required to implement all of these service types, and MUST treat
1695
unknown or unsupported Service-Types as though an Access-Reject
1696
had been received instead.
1698
A summary of the Service-Type Attribute format is shown below. The
1699
fields are transmitted from left to right.
1702
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1703
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1704
| Type | Length | Value
1705
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1707
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1719
The Value field is four octets.
1729
9 Callback NAS Prompt
1731
11 Callback Administrative
1738
Rigney, et al. Standards Track [Page 31]
1740
RFC 2865 RADIUS June 2000
1743
The service types are defined as follows when used in an Access-
1744
Accept. When used in an Access-Request, they MAY be considered to
1745
be a hint to the RADIUS server that the NAS has reason to believe
1746
the user would prefer the kind of service indicated, but the
1747
server is not required to honor the hint.
1749
Login The user should be connected to a host.
1751
Framed A Framed Protocol should be started for the
1752
User, such as PPP or SLIP.
1754
Callback Login The user should be disconnected and called
1755
back, then connected to a host.
1757
Callback Framed The user should be disconnected and called
1758
back, then a Framed Protocol should be started
1759
for the User, such as PPP or SLIP.
1761
Outbound The user should be granted access to outgoing
1764
Administrative The user should be granted access to the
1765
administrative interface to the NAS from which
1766
privileged commands can be executed.
1768
NAS Prompt The user should be provided a command prompt
1769
on the NAS from which non-privileged commands
1772
Authenticate Only Only Authentication is requested, and no
1773
authorization information needs to be returned
1774
in the Access-Accept (typically used by proxy
1775
servers rather than the NAS itself).
1777
Callback NAS Prompt The user should be disconnected and called
1778
back, then provided a command prompt on the
1779
NAS from which non-privileged commands can be
1782
Call Check Used by the NAS in an Access-Request packet to
1783
indicate that a call is being received and
1784
that the RADIUS server should send back an
1785
Access-Accept to answer the call, or an
1786
Access-Reject to not accept the call,
1787
typically based on the Called-Station-Id or
1788
Calling-Station-Id attributes. It is
1794
Rigney, et al. Standards Track [Page 32]
1796
RFC 2865 RADIUS June 2000
1799
recommended that such Access-Requests use the
1800
value of Calling-Station-Id as the value of
1803
Callback Administrative
1804
The user should be disconnected and called
1805
back, then granted access to the
1806
administrative interface to the NAS from which
1807
privileged commands can be executed.
1809
5.7. Framed-Protocol
1813
This Attribute indicates the framing to be used for framed access.
1814
It MAY be used in both Access-Request and Access-Accept packets.
1816
A summary of the Framed-Protocol Attribute format is shown below.
1817
The fields are transmitted from left to right.
1820
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1821
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1822
| Type | Length | Value
1823
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1825
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1829
7 for Framed-Protocol.
1837
The Value field is four octets.
1841
3 AppleTalk Remote Access Protocol (ARAP)
1842
4 Gandalf proprietary SingleLink/MultiLink protocol
1843
5 Xylogics proprietary IPX/SLIP
1850
Rigney, et al. Standards Track [Page 33]
1852
RFC 2865 RADIUS June 2000
1855
5.8. Framed-IP-Address
1859
This Attribute indicates the address to be configured for the
1860
user. It MAY be used in Access-Accept packets. It MAY be used in
1861
an Access-Request packet as a hint by the NAS to the server that
1862
it would prefer that address, but the server is not required to
1865
A summary of the Framed-IP-Address Attribute format is shown below.
1866
The fields are transmitted from left to right.
1869
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1870
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1871
| Type | Length | Address
1872
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1874
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1878
8 for Framed-IP-Address.
1886
The Address field is four octets. The value 0xFFFFFFFF indicates
1887
that the NAS Should allow the user to select an address (e.g.
1888
Negotiated). The value 0xFFFFFFFE indicates that the NAS should
1889
select an address for the user (e.g. Assigned from a pool of
1890
addresses kept by the NAS). Other valid values indicate that the
1891
NAS should use that value as the user's IP address.
1893
5.9. Framed-IP-Netmask
1897
This Attribute indicates the IP netmask to be configured for the
1898
user when the user is a router to a network. It MAY be used in
1899
Access-Accept packets. It MAY be used in an Access-Request packet
1900
as a hint by the NAS to the server that it would prefer that
1901
netmask, but the server is not required to honor the hint.
1906
Rigney, et al. Standards Track [Page 34]
1908
RFC 2865 RADIUS June 2000
1911
A summary of the Framed-IP-Netmask Attribute format is shown below.
1912
The fields are transmitted from left to right.
1915
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1916
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1917
| Type | Length | Address
1918
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1920
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1924
9 for Framed-IP-Netmask.
1932
The Address field is four octets specifying the IP netmask of the
1935
5.10. Framed-Routing
1939
This Attribute indicates the routing method for the user, when the
1940
user is a router to a network. It is only used in Access-Accept
1943
A summary of the Framed-Routing Attribute format is shown below. The
1944
fields are transmitted from left to right.
1947
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1948
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1949
| Type | Length | Value
1950
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1952
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1956
10 for Framed-Routing.
1962
Rigney, et al. Standards Track [Page 35]
1964
RFC 2865 RADIUS June 2000
1973
The Value field is four octets.
1976
1 Send routing packets
1977
2 Listen for routing packets
1984
This Attribute indicates the name of the filter list for this
1985
user. Zero or more Filter-Id attributes MAY be sent in an
1986
Access-Accept packet.
1988
Identifying a filter list by name allows the filter to be used on
1989
different NASes without regard to filter-list implementation
1992
A summary of the Filter-Id Attribute format is shown below. The
1993
fields are transmitted from left to right.
1996
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
1997
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
1998
| Type | Length | Text ...
1999
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2011
The Text field is one or more octets, and its contents are
2012
implementation dependent. It is intended to be human readable and
2013
MUST NOT affect operation of the protocol. It is recommended that
2014
the message contain UTF-8 encoded 10646 [7] characters.
2018
Rigney, et al. Standards Track [Page 36]
2020
RFC 2865 RADIUS June 2000
2027
This Attribute indicates the Maximum Transmission Unit to be
2028
configured for the user, when it is not negotiated by some other
2029
means (such as PPP). It MAY be used in Access-Accept packets. It
2030
MAY be used in an Access-Request packet as a hint by the NAS to
2031
the server that it would prefer that value, but the server is not
2032
required to honor the hint.
2034
A summary of the Framed-MTU Attribute format is shown below. The
2035
fields are transmitted from left to right.
2038
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2039
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2040
| Type | Length | Value
2041
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2043
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2055
The Value field is four octets. Despite the size of the field,
2056
values range from 64 to 65535.
2058
5.13. Framed-Compression
2062
This Attribute indicates a compression protocol to be used for the
2063
link. It MAY be used in Access-Accept packets. It MAY be used in
2064
an Access-Request packet as a hint to the server that the NAS
2065
would prefer to use that compression, but the server is not
2066
required to honor the hint.
2068
More than one compression protocol Attribute MAY be sent. It is
2069
the responsibility of the NAS to apply the proper compression
2070
protocol to appropriate link traffic.
2074
Rigney, et al. Standards Track [Page 37]
2076
RFC 2865 RADIUS June 2000
2079
A summary of the Framed-Compression Attribute format is shown below.
2080
The fields are transmitted from left to right.
2083
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2084
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2085
| Type | Length | Value
2086
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2088
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2092
13 for Framed-Compression.
2100
The Value field is four octets.
2103
1 VJ TCP/IP header compression [10]
2104
2 IPX header compression
2105
3 Stac-LZS compression
2111
This Attribute indicates the system with which to connect the user,
2112
when the Login-Service Attribute is included. It MAY be used in
2113
Access-Accept packets. It MAY be used in an Access-Request packet as
2114
a hint to the server that the NAS would prefer to use that host, but
2115
the server is not required to honor the hint.
2117
A summary of the Login-IP-Host Attribute format is shown below. The
2118
fields are transmitted from left to right.
2130
Rigney, et al. Standards Track [Page 38]
2132
RFC 2865 RADIUS June 2000
2136
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2137
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2138
| Type | Length | Address
2139
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2141
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2145
14 for Login-IP-Host.
2153
The Address field is four octets. The value 0xFFFFFFFF indicates
2154
that the NAS SHOULD allow the user to select an address. The
2155
value 0 indicates that the NAS SHOULD select a host to connect the
2156
user to. Other values indicate the address the NAS SHOULD connect
2163
This Attribute indicates the service to use to connect the user to
2164
the login host. It is only used in Access-Accept packets.
2166
A summary of the Login-Service Attribute format is shown below. The
2167
fields are transmitted from left to right.
2170
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2171
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2172
| Type | Length | Value
2173
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2175
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2179
15 for Login-Service.
2186
Rigney, et al. Standards Track [Page 39]
2188
RFC 2865 RADIUS June 2000
2197
The Value field is four octets.
2202
3 PortMaster (proprietary)
2206
8 TCP Clear Quiet (suppresses any NAS-generated connect string)
2208
5.16. Login-TCP-Port
2212
This Attribute indicates the TCP port with which the user is to be
2213
connected, when the Login-Service Attribute is also present. It
2214
is only used in Access-Accept packets.
2216
A summary of the Login-TCP-Port Attribute format is shown below. The
2217
fields are transmitted from left to right.
2220
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2221
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2222
| Type | Length | Value
2223
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2225
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2229
16 for Login-TCP-Port.
2237
The Value field is four octets. Despite the size of the field,
2238
values range from 0 to 65535.
2242
Rigney, et al. Standards Track [Page 40]
2244
RFC 2865 RADIUS June 2000
2251
ATTRIBUTE TYPE 17 HAS NOT BEEN ASSIGNED.
2257
This Attribute indicates text which MAY be displayed to the user.
2259
When used in an Access-Accept, it is the success message.
2261
When used in an Access-Reject, it is the failure message. It MAY
2262
indicate a dialog message to prompt the user before another
2263
Access-Request attempt.
2265
When used in an Access-Challenge, it MAY indicate a dialog message
2266
to prompt the user for a response.
2268
Multiple Reply-Message's MAY be included and if any are displayed,
2269
they MUST be displayed in the same order as they appear in the
2272
A summary of the Reply-Message Attribute format is shown below. The
2273
fields are transmitted from left to right.
2276
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2277
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2278
| Type | Length | Text ...
2279
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2283
18 for Reply-Message.
2291
The Text field is one or more octets, and its contents are
2292
implementation dependent. It is intended to be human readable,
2293
and MUST NOT affect operation of the protocol. It is recommended
2294
that the message contain UTF-8 encoded 10646 [7] characters.
2298
Rigney, et al. Standards Track [Page 41]
2300
RFC 2865 RADIUS June 2000
2303
5.19. Callback-Number
2307
This Attribute indicates a dialing string to be used for callback.
2308
It MAY be used in Access-Accept packets. It MAY be used in an
2309
Access-Request packet as a hint to the server that a Callback
2310
service is desired, but the server is not required to honor the
2313
A summary of the Callback-Number Attribute format is shown below.
2314
The fields are transmitted from left to right.
2317
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2318
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2319
| Type | Length | String ...
2320
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2324
19 for Callback-Number.
2332
The String field is one or more octets. The actual format of the
2333
information is site or application specific, and a robust
2334
implementation SHOULD support the field as undistinguished octets.
2336
The codification of the range of allowed usage of this field is
2337
outside the scope of this specification.
2343
This Attribute indicates the name of a place to be called, to be
2344
interpreted by the NAS. It MAY be used in Access-Accept packets.
2354
Rigney, et al. Standards Track [Page 42]
2356
RFC 2865 RADIUS June 2000
2359
A summary of the Callback-Id Attribute format is shown below. The
2360
fields are transmitted from left to right.
2363
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2364
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2365
| Type | Length | String ...
2366
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2378
The String field is one or more octets. The actual format of the
2379
information is site or application specific, and a robust
2380
implementation SHOULD support the field as undistinguished octets.
2382
The codification of the range of allowed usage of this field is
2383
outside the scope of this specification.
2389
ATTRIBUTE TYPE 21 HAS NOT BEEN ASSIGNED.
2395
This Attribute provides routing information to be configured for
2396
the user on the NAS. It is used in the Access-Accept packet and
2397
can appear multiple times.
2399
A summary of the Framed-Route Attribute format is shown below. The
2400
fields are transmitted from left to right.
2403
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
2404
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2405
| Type | Length | Text ...
2406
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2410
Rigney, et al. Standards Track [Page 43]
2412
RFC 2865 RADIUS June 2000
2417
22 for Framed-Route.
2425
The Text field is one or more octets, and its contents are
2426
implementation dependent. It is intended to be human readable and
2427
MUST NOT affect operation of the protocol. It is recommended that
2428
the message contain UTF-8 encoded 10646 [7] characters.
2430
For IP routes, it SHOULD contain a destination prefix in dotted
2431
quad form optionally followed by a slash and a decimal length
2432
specifier stating how many high order bits of the prefix to use.
2433
That is followed by a space, a gateway address in dotted quad
2434
form, a space, and one or more metrics separated by spaces. For
2435
example, "192.168.1.0/24 192.168.1.1 1 2 -1 3 400". The length
2436
specifier may be omitted, in which case it defaults to 8 bits for
2437
class A prefixes, 16 bits for class B prefixes, and 24 bits for
2438
class C prefixes. For example, "192.168.1.0 192.168.1.1 1".
2440
Whenever the gateway address is specified as "0.0.0.0" the IP
2441
address of the user SHOULD be used as the gateway address.
2443
5.23. Framed-IPX-Network
2447
This Attribute indicates the IPX Network number to be configured
2448
for the user. It is used in Access-Accept packets.
2450
A summary of the Framed-IPX-Network Attribute format is shown below.
2451
The fields are transmitted from left to right.
2454
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2455
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2456
| Type | Length | Value
2457
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2459
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2466
Rigney, et al. Standards Track [Page 44]
2468
RFC 2865 RADIUS June 2000
2473
23 for Framed-IPX-Network.
2481
The Value field is four octets. The value 0xFFFFFFFE indicates
2482
that the NAS should select an IPX network for the user (e.g.
2483
assigned from a pool of one or more IPX networks kept by the NAS).
2484
Other values should be used as the IPX network for the link to the
2491
This Attribute is available to be sent by the server to the client
2492
in an Access-Challenge and MUST be sent unmodified from the client
2493
to the server in the new Access-Request reply to that challenge,
2496
This Attribute is available to be sent by the server to the client
2497
in an Access-Accept that also includes a Termination-Action
2498
Attribute with the value of RADIUS-Request. If the NAS performs
2499
the Termination-Action by sending a new Access-Request upon
2500
termination of the current session, it MUST include the State
2501
attribute unchanged in that Access-Request.
2503
In either usage, the client MUST NOT interpret the attribute
2504
locally. A packet must have only zero or one State Attribute.
2505
Usage of the State Attribute is implementation dependent.
2507
A summary of the State Attribute format is shown below. The fields
2508
are transmitted from left to right.
2511
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2512
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2513
| Type | Length | String ...
2514
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2522
Rigney, et al. Standards Track [Page 45]
2524
RFC 2865 RADIUS June 2000
2533
The String field is one or more octets. The actual format of the
2534
information is site or application specific, and a robust
2535
implementation SHOULD support the field as undistinguished octets.
2537
The codification of the range of allowed usage of this field is
2538
outside the scope of this specification.
2544
This Attribute is available to be sent by the server to the client
2545
in an Access-Accept and SHOULD be sent unmodified by the client to
2546
the accounting server as part of the Accounting-Request packet if
2547
accounting is supported. The client MUST NOT interpret the
2550
A summary of the Class Attribute format is shown below. The fields
2551
are transmitted from left to right.
2554
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2555
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2556
| Type | Length | String ...
2557
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2569
The String field is one or more octets. The actual format of the
2570
information is site or application specific, and a robust
2571
implementation SHOULD support the field as undistinguished octets.
2573
The codification of the range of allowed usage of this field is
2574
outside the scope of this specification.
2578
Rigney, et al. Standards Track [Page 46]
2580
RFC 2865 RADIUS June 2000
2583
5.26. Vendor-Specific
2587
This Attribute is available to allow vendors to support their own
2588
extended Attributes not suitable for general usage. It MUST not
2589
affect the operation of the RADIUS protocol.
2591
Servers not equipped to interpret the vendor-specific information
2592
sent by a client MUST ignore it (although it may be reported).
2593
Clients which do not receive desired vendor-specific information
2594
SHOULD make an attempt to operate without it, although they may do
2595
so (and report they are doing so) in a degraded mode.
2597
A summary of the Vendor-Specific Attribute format is shown below.
2598
The fields are transmitted from left to right.
2601
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2602
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2603
| Type | Length | Vendor-Id
2604
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2605
Vendor-Id (cont) | String...
2606
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2610
26 for Vendor-Specific.
2618
The high-order octet is 0 and the low-order 3 octets are the SMI
2619
Network Management Private Enterprise Code of the Vendor in
2620
network byte order, as defined in the "Assigned Numbers" RFC [6].
2624
The String field is one or more octets. The actual format of the
2625
information is site or application specific, and a robust
2626
implementation SHOULD support the field as undistinguished octets.
2628
The codification of the range of allowed usage of this field is
2629
outside the scope of this specification.
2634
Rigney, et al. Standards Track [Page 47]
2636
RFC 2865 RADIUS June 2000
2639
It SHOULD be encoded as a sequence of vendor type / vendor length
2640
/ value fields, as follows. The Attribute-Specific field is
2641
dependent on the vendor's definition of that attribute. An
2642
example encoding of the Vendor-Specific attribute using this
2646
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2647
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2648
| Type | Length | Vendor-Id
2649
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2650
Vendor-Id (cont) | Vendor type | Vendor length |
2651
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2652
| Attribute-Specific...
2653
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2655
Multiple subattributes MAY be encoded within a single Vendor-
2656
Specific attribute, although they do not have to be.
2658
5.27. Session-Timeout
2662
This Attribute sets the maximum number of seconds of service to be
2663
provided to the user before termination of the session or prompt.
2664
This Attribute is available to be sent by the server to the client
2665
in an Access-Accept or Access-Challenge.
2667
A summary of the Session-Timeout Attribute format is shown below.
2668
The fields are transmitted from left to right.
2671
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2672
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2673
| Type | Length | Value
2674
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2676
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2680
27 for Session-Timeout.
2690
Rigney, et al. Standards Track [Page 48]
2692
RFC 2865 RADIUS June 2000
2697
The field is 4 octets, containing a 32-bit unsigned integer with
2698
the maximum number of seconds this user should be allowed to
2699
remain connected by the NAS.
2705
This Attribute sets the maximum number of consecutive seconds of
2706
idle connection allowed to the user before termination of the
2707
session or prompt. This Attribute is available to be sent by the
2708
server to the client in an Access-Accept or Access-Challenge.
2710
A summary of the Idle-Timeout Attribute format is shown below. The
2711
fields are transmitted from left to right.
2714
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2715
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2716
| Type | Length | Value
2717
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2719
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2723
28 for Idle-Timeout.
2731
The field is 4 octets, containing a 32-bit unsigned integer with
2732
the maximum number of consecutive seconds of idle time this user
2733
should be permitted before being disconnected by the NAS.
2735
5.29. Termination-Action
2739
This Attribute indicates what action the NAS should take when the
2740
specified service is completed. It is only used in Access-Accept
2746
Rigney, et al. Standards Track [Page 49]
2748
RFC 2865 RADIUS June 2000
2751
A summary of the Termination-Action Attribute format is shown below.
2752
The fields are transmitted from left to right.
2755
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2756
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2757
| Type | Length | Value
2758
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2760
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2764
29 for Termination-Action.
2772
The Value field is four octets.
2777
If the Value is set to RADIUS-Request, upon termination of the
2778
specified service the NAS MAY send a new Access-Request to the
2779
RADIUS server, including the State attribute if any.
2781
5.30. Called-Station-Id
2785
This Attribute allows the NAS to send in the Access-Request packet
2786
the phone number that the user called, using Dialed Number
2787
Identification (DNIS) or similar technology. Note that this may
2788
be different from the phone number the call comes in on. It is
2789
only used in Access-Request packets.
2791
A summary of the Called-Station-Id Attribute format is shown below.
2792
The fields are transmitted from left to right.
2795
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2796
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2797
| Type | Length | String ...
2798
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2802
Rigney, et al. Standards Track [Page 50]
2804
RFC 2865 RADIUS June 2000
2809
30 for Called-Station-Id.
2817
The String field is one or more octets, containing the phone
2818
number that the user's call came in on.
2820
The actual format of the information is site or application
2821
specific. UTF-8 encoded 10646 [7] characters are recommended, but
2822
a robust implementation SHOULD support the field as
2823
undistinguished octets.
2825
The codification of the range of allowed usage of this field is
2826
outside the scope of this specification.
2828
5.31. Calling-Station-Id
2832
This Attribute allows the NAS to send in the Access-Request packet
2833
the phone number that the call came from, using Automatic Number
2834
Identification (ANI) or similar technology. It is only used in
2835
Access-Request packets.
2837
A summary of the Calling-Station-Id Attribute format is shown below.
2838
The fields are transmitted from left to right.
2841
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2842
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2843
| Type | Length | String ...
2844
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2848
31 for Calling-Station-Id.
2858
Rigney, et al. Standards Track [Page 51]
2860
RFC 2865 RADIUS June 2000
2865
The String field is one or more octets, containing the phone
2866
number that the user placed the call from.
2868
The actual format of the information is site or application
2869
specific. UTF-8 encoded 10646 [7] characters are recommended, but
2870
a robust implementation SHOULD support the field as
2871
undistinguished octets.
2873
The codification of the range of allowed usage of this field is
2874
outside the scope of this specification.
2876
5.32. NAS-Identifier
2880
This Attribute contains a string identifying the NAS originating
2881
the Access-Request. It is only used in Access-Request packets.
2882
Either NAS-IP-Address or NAS-Identifier MUST be present in an
2883
Access-Request packet.
2885
Note that NAS-Identifier MUST NOT be used to select the shared
2886
secret used to authenticate the request. The source IP address of
2887
the Access-Request packet MUST be used to select the shared
2890
A summary of the NAS-Identifier Attribute format is shown below. The
2891
fields are transmitted from left to right.
2894
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2895
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2896
| Type | Length | String ...
2897
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2901
32 for NAS-Identifier.
2914
Rigney, et al. Standards Track [Page 52]
2916
RFC 2865 RADIUS June 2000
2921
The String field is one or more octets, and should be unique to
2922
the NAS within the scope of the RADIUS server. For example, a
2923
fully qualified domain name would be suitable as a NAS-Identifier.
2925
The actual format of the information is site or application
2926
specific, and a robust implementation SHOULD support the field as
2927
undistinguished octets.
2929
The codification of the range of allowed usage of this field is
2930
outside the scope of this specification.
2936
This Attribute is available to be sent by a proxy server to
2937
another server when forwarding an Access-Request and MUST be
2938
returned unmodified in the Access-Accept, Access-Reject or
2939
Access-Challenge. When the proxy server receives the response to
2940
its request, it MUST remove its own Proxy-State (the last Proxy-
2941
State in the packet) before forwarding the response to the NAS.
2943
If a Proxy-State Attribute is added to a packet when forwarding
2944
the packet, the Proxy-State Attribute MUST be added after any
2945
existing Proxy-State attributes.
2947
The content of any Proxy-State other than the one added by the
2948
current server should be treated as opaque octets and MUST NOT
2949
affect operation of the protocol.
2951
Usage of the Proxy-State Attribute is implementation dependent. A
2952
description of its function is outside the scope of this
2955
A summary of the Proxy-State Attribute format is shown below. The
2956
fields are transmitted from left to right.
2959
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
2960
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2961
| Type | Length | String ...
2962
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
2970
Rigney, et al. Standards Track [Page 53]
2972
RFC 2865 RADIUS June 2000
2981
The String field is one or more octets. The actual format of the
2982
information is site or application specific, and a robust
2983
implementation SHOULD support the field as undistinguished octets.
2985
The codification of the range of allowed usage of this field is
2986
outside the scope of this specification.
2988
5.34. Login-LAT-Service
2992
This Attribute indicates the system with which the user is to be
2993
connected by LAT. It MAY be used in Access-Accept packets, but
2994
only when LAT is specified as the Login-Service. It MAY be used
2995
in an Access-Request packet as a hint to the server, but the
2996
server is not required to honor the hint.
2998
Administrators use the service attribute when dealing with
2999
clustered systems, such as a VAX or Alpha cluster. In such an
3000
environment several different time sharing hosts share the same
3001
resources (disks, printers, etc.), and administrators often
3002
configure each to offer access (service) to each of the shared
3003
resources. In this case, each host in the cluster advertises its
3004
services through LAT broadcasts.
3006
Sophisticated users often know which service providers (machines)
3007
are faster and tend to use a node name when initiating a LAT
3008
connection. Alternately, some administrators want particular
3009
users to use certain machines as a primitive form of load
3010
balancing (although LAT knows how to do load balancing itself).
3012
A summary of the Login-LAT-Service Attribute format is shown below.
3013
The fields are transmitted from left to right.
3016
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
3017
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3018
| Type | Length | String ...
3019
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3026
Rigney, et al. Standards Track [Page 54]
3028
RFC 2865 RADIUS June 2000
3033
34 for Login-LAT-Service.
3041
The String field is one or more octets, and contains the identity
3042
of the LAT service to use. The LAT Architecture allows this
3043
string to contain $ (dollar), - (hyphen), . (period), _
3044
(underscore), numerics, upper and lower case alphabetics, and the
3045
ISO Latin-1 character set extension [11]. All LAT string
3046
comparisons are case insensitive.
3048
5.35. Login-LAT-Node
3052
This Attribute indicates the Node with which the user is to be
3053
automatically connected by LAT. It MAY be used in Access-Accept
3054
packets, but only when LAT is specified as the Login-Service. It
3055
MAY be used in an Access-Request packet as a hint to the server,
3056
but the server is not required to honor the hint.
3058
A summary of the Login-LAT-Node Attribute format is shown below. The
3059
fields are transmitted from left to right.
3062
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
3063
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3064
| Type | Length | String ...
3065
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3069
35 for Login-LAT-Node.
3082
Rigney, et al. Standards Track [Page 55]
3084
RFC 2865 RADIUS June 2000
3089
The String field is one or more octets, and contains the identity
3090
of the LAT Node to connect the user to. The LAT Architecture
3091
allows this string to contain $ (dollar), - (hyphen), . (period),
3092
_ (underscore), numerics, upper and lower case alphabetics, and
3093
the ISO Latin-1 character set extension. All LAT string
3094
comparisons are case insensitive.
3096
5.36. Login-LAT-Group
3100
This Attribute contains a string identifying the LAT group codes
3101
which this user is authorized to use. It MAY be used in Access-
3102
Accept packets, but only when LAT is specified as the Login-
3103
Service. It MAY be used in an Access-Request packet as a hint to
3104
the server, but the server is not required to honor the hint.
3106
LAT supports 256 different group codes, which LAT uses as a form
3107
of access rights. LAT encodes the group codes as a 256 bit
3110
Administrators can assign one or more of the group code bits at
3111
the LAT service provider; it will only accept LAT connections that
3112
have these group codes set in the bit map. The administrators
3113
assign a bitmap of authorized group codes to each user; LAT gets
3114
these from the operating system, and uses these in its requests to
3115
the service providers.
3117
A summary of the Login-LAT-Group Attribute format is shown below.
3118
The fields are transmitted from left to right.
3121
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
3122
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3123
| Type | Length | String ...
3124
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3128
36 for Login-LAT-Group.
3138
Rigney, et al. Standards Track [Page 56]
3140
RFC 2865 RADIUS June 2000
3145
The String field is a 32 octet bit map, most significant octet
3146
first. A robust implementation SHOULD support the field as
3147
undistinguished octets.
3149
The codification of the range of allowed usage of this field is
3150
outside the scope of this specification.
3152
5.37. Framed-AppleTalk-Link
3156
This Attribute indicates the AppleTalk network number which should
3157
be used for the serial link to the user, which is another
3158
AppleTalk router. It is only used in Access-Accept packets. It
3159
is never used when the user is not another router.
3161
A summary of the Framed-AppleTalk-Link Attribute format is shown
3162
below. The fields are transmitted from left to right.
3165
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
3166
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3167
| Type | Length | Value
3168
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3170
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3174
37 for Framed-AppleTalk-Link.
3182
The Value field is four octets. Despite the size of the field,
3183
values range from 0 to 65535. The special value of 0 indicates
3184
that this is an unnumbered serial link. A value of 1-65535 means
3185
that the serial line between the NAS and the user should be
3186
assigned that value as an AppleTalk network number.
3194
Rigney, et al. Standards Track [Page 57]
3196
RFC 2865 RADIUS June 2000
3199
5.38. Framed-AppleTalk-Network
3203
This Attribute indicates the AppleTalk Network number which the
3204
NAS should probe to allocate an AppleTalk node for the user. It
3205
is only used in Access-Accept packets. It is never used when the
3206
user is another router. Multiple instances of this Attribute
3207
indicate that the NAS may probe using any of the network numbers
3210
A summary of the Framed-AppleTalk-Network Attribute format is shown
3211
below. The fields are transmitted from left to right.
3214
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
3215
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3216
| Type | Length | Value
3217
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3219
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3223
38 for Framed-AppleTalk-Network.
3231
The Value field is four octets. Despite the size of the field,
3232
values range from 0 to 65535. The special value 0 indicates that
3233
the NAS should assign a network for the user, using its default
3234
cable range. A value between 1 and 65535 (inclusive) indicates
3235
the AppleTalk Network the NAS should probe to find an address for
3238
5.39. Framed-AppleTalk-Zone
3242
This Attribute indicates the AppleTalk Default Zone to be used for
3243
this user. It is only used in Access-Accept packets. Multiple
3244
instances of this attribute in the same packet are not allowed.
3250
Rigney, et al. Standards Track [Page 58]
3252
RFC 2865 RADIUS June 2000
3255
A summary of the Framed-AppleTalk-Zone Attribute format is shown
3256
below. The fields are transmitted from left to right.
3259
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4
3260
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3261
| Type | Length | String ...
3262
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3266
39 for Framed-AppleTalk-Zone.
3274
The name of the Default AppleTalk Zone to be used for this user.
3275
A robust implementation SHOULD support the field as
3276
undistinguished octets.
3278
The codification of the range of allowed usage of this field is
3279
outside the scope of this specification.
3281
5.40. CHAP-Challenge
3285
This Attribute contains the CHAP Challenge sent by the NAS to a
3286
PPP Challenge-Handshake Authentication Protocol (CHAP) user. It
3287
is only used in Access-Request packets.
3289
If the CHAP challenge value is 16 octets long it MAY be placed in
3290
the Request Authenticator field instead of using this attribute.
3292
A summary of the CHAP-Challenge Attribute format is shown below. The
3293
fields are transmitted from left to right.
3296
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
3297
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3298
| Type | Length | String...
3299
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3306
Rigney, et al. Standards Track [Page 59]
3308
RFC 2865 RADIUS June 2000
3313
60 for CHAP-Challenge.
3321
The String field contains the CHAP Challenge.
3327
This Attribute indicates the type of the physical port of the NAS
3328
which is authenticating the user. It can be used instead of or in
3329
addition to the NAS-Port (5) attribute. It is only used in
3330
Access-Request packets. Either NAS-Port (5) or NAS-Port-Type or
3331
both SHOULD be present in an Access-Request packet, if the NAS
3332
differentiates among its ports.
3334
A summary of the NAS-Port-Type Attribute format is shown below. The
3335
fields are transmitted from left to right.
3338
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
3339
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3340
| Type | Length | Value
3341
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3343
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3347
61 for NAS-Port-Type.
3355
The Value field is four octets. "Virtual" refers to a connection
3356
to the NAS via some transport protocol, instead of through a
3357
physical port. For example, if a user telnetted into a NAS to
3362
Rigney, et al. Standards Track [Page 60]
3364
RFC 2865 RADIUS June 2000
3367
authenticate himself as an Outbound-User, the Access-Request might
3368
include NAS-Port-Type = Virtual as a hint to the RADIUS server
3369
that the user was not on a physical port.
3378
7 HDLC Clear Channel
3382
11 SDSL - Symmetric DSL
3383
12 ADSL-CAP - Asymmetric DSL, Carrierless Amplitude Phase
3385
13 ADSL-DMT - Asymmetric DSL, Discrete Multi-Tone
3386
14 IDSL - ISDN Digital Subscriber Line
3388
16 xDSL - Digital Subscriber Line of unknown type
3391
19 Wireless - IEEE 802.11
3393
PIAFS is a form of wireless ISDN commonly used in Japan, and
3394
stands for PHS (Personal Handyphone System) Internet Access Forum
3401
This Attribute sets the maximum number of ports to be provided to
3402
the user by the NAS. This Attribute MAY be sent by the server to
3403
the client in an Access-Accept packet. It is intended for use in
3404
conjunction with Multilink PPP [12] or similar uses. It MAY also
3405
be sent by the NAS to the server as a hint that that many ports
3406
are desired for use, but the server is not required to honor the
3409
A summary of the Port-Limit Attribute format is shown below. The
3410
fields are transmitted from left to right.
3418
Rigney, et al. Standards Track [Page 61]
3420
RFC 2865 RADIUS June 2000
3424
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
3425
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3426
| Type | Length | Value
3427
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3429
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3441
The field is 4 octets, containing a 32-bit unsigned integer with
3442
the maximum number of ports this user should be allowed to connect
3445
5.43. Login-LAT-Port
3449
This Attribute indicates the Port with which the user is to be
3450
connected by LAT. It MAY be used in Access-Accept packets, but
3451
only when LAT is specified as the Login-Service. It MAY be used
3452
in an Access-Request packet as a hint to the server, but the
3453
server is not required to honor the hint.
3455
A summary of the Login-LAT-Port Attribute format is shown below. The
3456
fields are transmitted from left to right.
3459
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
3460
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3461
| Type | Length | String ...
3462
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
3466
63 for Login-LAT-Port.
3474
Rigney, et al. Standards Track [Page 62]
3476
RFC 2865 RADIUS June 2000
3481
The String field is one or more octets, and contains the identity
3482
of the LAT port to use. The LAT Architecture allows this string
3483
to contain $ (dollar), - (hyphen), . (period), _ (underscore),
3484
numerics, upper and lower case alphabetics, and the ISO Latin-1
3485
character set extension. All LAT string comparisons are case
3488
5.44. Table of Attributes
3490
The following table provides a guide to which attributes may be found
3491
in which kinds of packets, and in what quantity.
3493
Request Accept Reject Challenge # Attribute
3494
0-1 0-1 0 0 1 User-Name
3495
0-1 0 0 0 2 User-Password [Note 1]
3496
0-1 0 0 0 3 CHAP-Password [Note 1]
3497
0-1 0 0 0 4 NAS-IP-Address [Note 2]
3498
0-1 0 0 0 5 NAS-Port
3499
0-1 0-1 0 0 6 Service-Type
3500
0-1 0-1 0 0 7 Framed-Protocol
3501
0-1 0-1 0 0 8 Framed-IP-Address
3502
0-1 0-1 0 0 9 Framed-IP-Netmask
3503
0 0-1 0 0 10 Framed-Routing
3504
0 0+ 0 0 11 Filter-Id
3505
0-1 0-1 0 0 12 Framed-MTU
3506
0+ 0+ 0 0 13 Framed-Compression
3507
0+ 0+ 0 0 14 Login-IP-Host
3508
0 0-1 0 0 15 Login-Service
3509
0 0-1 0 0 16 Login-TCP-Port
3510
0 0+ 0+ 0+ 18 Reply-Message
3511
0-1 0-1 0 0 19 Callback-Number
3512
0 0-1 0 0 20 Callback-Id
3513
0 0+ 0 0 22 Framed-Route
3514
0 0-1 0 0 23 Framed-IPX-Network
3515
0-1 0-1 0 0-1 24 State [Note 1]
3517
0+ 0+ 0 0+ 26 Vendor-Specific
3518
0 0-1 0 0-1 27 Session-Timeout
3519
0 0-1 0 0-1 28 Idle-Timeout
3520
0 0-1 0 0 29 Termination-Action
3521
0-1 0 0 0 30 Called-Station-Id
3522
0-1 0 0 0 31 Calling-Station-Id
3523
0-1 0 0 0 32 NAS-Identifier [Note 2]
3524
0+ 0+ 0+ 0+ 33 Proxy-State
3525
0-1 0-1 0 0 34 Login-LAT-Service
3526
0-1 0-1 0 0 35 Login-LAT-Node
3530
Rigney, et al. Standards Track [Page 63]
3532
RFC 2865 RADIUS June 2000
3535
0-1 0-1 0 0 36 Login-LAT-Group
3536
0 0-1 0 0 37 Framed-AppleTalk-Link
3537
0 0+ 0 0 38 Framed-AppleTalk-Network
3538
0 0-1 0 0 39 Framed-AppleTalk-Zone
3539
0-1 0 0 0 60 CHAP-Challenge
3540
0-1 0 0 0 61 NAS-Port-Type
3541
0-1 0-1 0 0 62 Port-Limit
3542
0-1 0-1 0 0 63 Login-LAT-Port
3543
Request Accept Reject Challenge # Attribute
3545
[Note 1] An Access-Request MUST contain either a User-Password or a
3546
CHAP-Password or State. An Access-Request MUST NOT contain both a
3547
User-Password and a CHAP-Password. If future extensions allow other
3548
kinds of authentication information to be conveyed, the attribute for
3549
that can be used in an Access-Request instead of User-Password or
3552
[Note 2] An Access-Request MUST contain either a NAS-IP-Address or a
3553
NAS-Identifier (or both).
3555
The following table defines the meaning of the above table entries.
3557
0 This attribute MUST NOT be present in packet.
3558
0+ Zero or more instances of this attribute MAY be present in packet.
3559
0-1 Zero or one instance of this attribute MAY be present in packet.
3560
1 Exactly one instance of this attribute MUST be present in packet.
3562
6. IANA Considerations
3564
This section provides guidance to the Internet Assigned Numbers
3565
Authority (IANA) regarding registration of values related to the
3566
RADIUS protocol, in accordance with BCP 26 [13].
3568
There are three name spaces in RADIUS that require registration:
3569
Packet Type Codes, Attribute Types, and Attribute Values (for certain
3572
RADIUS is not intended as a general-purpose Network Access Server
3573
(NAS) management protocol, and allocations should not be made for
3574
purposes unrelated to Authentication, Authorization or Accounting.
3576
6.1. Definition of Terms
3578
The following terms are used here with the meanings defined in
3579
BCP 26: "name space", "assigned value", "registration".
3586
Rigney, et al. Standards Track [Page 64]
3588
RFC 2865 RADIUS June 2000
3591
The following policies are used here with the meanings defined in
3592
BCP 26: "Private Use", "First Come First Served", "Expert Review",
3593
"Specification Required", "IETF Consensus", "Standards Action".
3595
6.2. Recommended Registration Policies
3597
For registration requests where a Designated Expert should be
3598
consulted, the IESG Area Director for Operations should appoint the
3601
For registration requests requiring Expert Review, the ietf-radius
3602
mailing list should be consulted.
3604
Packet Type Codes have a range from 1 to 254, of which 1-5,11-13 have
3605
been allocated. Because a new Packet Type has considerable impact on
3606
interoperability, a new Packet Type Code requires Standards Action,
3607
and should be allocated starting at 14.
3609
Attribute Types have a range from 1 to 255, and are the scarcest
3610
resource in RADIUS, thus must be allocated with care. Attributes
3611
1-53,55,60-88,90-91 have been allocated, with 17 and 21 available for
3612
re-use. Attributes 17, 21, 54, 56-59, 89, 92-191 may be allocated
3613
following Expert Review, with Specification Required. Release of
3614
blocks of Attribute Types (more than 3 at a time for a given purpose)
3615
should require IETF Consensus. It is recommended that attributes 17
3616
and 21 be used only after all others are exhausted.
3618
Note that RADIUS defines a mechanism for Vendor-Specific extensions
3619
(Attribute 26) and the use of that should be encouraged instead of
3620
allocation of global attribute types, for functions specific only to
3621
one vendor's implementation of RADIUS, where no interoperability is
3624
As stated in the "Attributes" section above:
3626
"[Attribute Type] Values 192-223 are reserved for experimental
3627
use, values 224-240 are reserved for implementation-specific use,
3628
and values 241-255 are reserved and should not be used."
3630
Therefore Attribute values 192-240 are considered Private Use, and
3631
values 241-255 require Standards Action.
3633
Certain attributes (for example, NAS-Port-Type) in RADIUS define a
3634
list of values to correspond with various meanings. There can be 4
3635
billion (2^32) values for each attribute. Adding additional values to
3636
the list can be done on a First Come, First Served basis by the IANA.
3642
Rigney, et al. Standards Track [Page 65]
3644
RFC 2865 RADIUS June 2000
3649
A few examples are presented to illustrate the flow of packets and
3650
use of typical attributes. These examples are not intended to be
3651
exhaustive, many others are possible. Hexadecimal dumps of the
3652
example packets are given in network byte order, using the shared
3655
7.1. User Telnet to Specified Host
3657
The NAS at 192.168.1.16 sends an Access-Request UDP packet to the
3658
RADIUS Server for a user named nemo logging in on port 3 with
3659
password "arctangent".
3661
The Request Authenticator is a 16 octet random number generated by
3664
The User-Password is 16 octets of password padded at end with nulls,
3665
XORed with MD5(shared secret|Request Authenticator).
3667
01 00 00 38 0f 40 3f 94 73 97 80 57 bd 83 d5 cb
3668
98 f4 22 7a 01 06 6e 65 6d 6f 02 12 0d be 70 8d
3669
93 d4 13 ce 31 96 e4 3f 78 2a 0a ee 04 06 c0 a8
3670
01 10 05 06 00 00 00 03
3672
1 Code = Access-Request (1)
3675
16 Request Authenticator
3678
6 User-Name = "nemo"
3680
6 NAS-IP-Address = 192.168.1.16
3683
The RADIUS server authenticates nemo, and sends an Access-Accept UDP
3684
packet to the NAS telling it to telnet nemo to host 192.168.1.3.
3686
The Response Authenticator is a 16-octet MD5 checksum of the code
3687
(2), id (0), Length (38), the Request Authenticator from above, the
3688
attributes in this reply, and the shared secret.
3698
Rigney, et al. Standards Track [Page 66]
3700
RFC 2865 RADIUS June 2000
3703
02 00 00 26 86 fe 22 0e 76 24 ba 2a 10 05 f6 bf
3704
9b 55 e0 b2 06 06 00 00 00 01 0f 06 00 00 00 00
3707
1 Code = Access-Accept (2)
3708
1 ID = 0 (same as in Access-Request)
3710
16 Response Authenticator
3713
6 Service-Type (6) = Login (1)
3714
6 Login-Service (15) = Telnet (0)
3715
6 Login-IP-Host (14) = 192.168.1.3
3717
7.2. Framed User Authenticating with CHAP
3719
The NAS at 192.168.1.16 sends an Access-Request UDP packet to the
3720
RADIUS Server for a user named flopsy logging in on port 20 with PPP,
3721
authenticating using CHAP. The NAS sends along the Service-Type and
3722
Framed-Protocol attributes as a hint to the RADIUS server that this
3723
user is looking for PPP, although the NAS is not required to do so.
3725
The Request Authenticator is a 16 octet random number generated by
3726
the NAS, and is also used as the CHAP Challenge.
3728
The CHAP-Password consists of a 1 octet CHAP ID, in this case 22,
3729
followed by the 16 octet CHAP response.
3731
01 01 00 47 2a ee 86 f0 8d 0d 55 96 9c a5 97 8e
3732
0d 33 67 a2 01 08 66 6c 6f 70 73 79 03 13 16 e9
3733
75 57 c3 16 18 58 95 f2 93 ff 63 44 07 72 75 04
3734
06 c0 a8 01 10 05 06 00 00 00 14 06 06 00 00 00
3735
02 07 06 00 00 00 01
3737
1 Code = 1 (Access-Request)
3740
16 Request Authenticator
3743
8 User-Name (1) = "flopsy"
3744
19 CHAP-Password (3)
3745
6 NAS-IP-Address (4) = 192.168.1.16
3747
6 Service-Type (6) = Framed (2)
3748
6 Framed-Protocol (7) = PPP (1)
3754
Rigney, et al. Standards Track [Page 67]
3756
RFC 2865 RADIUS June 2000
3759
The RADIUS server authenticates flopsy, and sends an Access-Accept
3760
UDP packet to the NAS telling it to start PPP service and assign an
3761
address for the user out of its dynamic address pool.
3763
The Response Authenticator is a 16-octet MD5 checksum of the code
3764
(2), id (1), Length (56), the Request Authenticator from above, the
3765
attributes in this reply, and the shared secret.
3767
02 01 00 38 15 ef bc 7d ab 26 cf a3 dc 34 d9 c0
3768
3c 86 01 a4 06 06 00 00 00 02 07 06 00 00 00 01
3769
08 06 ff ff ff fe 0a 06 00 00 00 02 0d 06 00 00
3770
00 01 0c 06 00 00 05 dc
3772
1 Code = Access-Accept (2)
3773
1 ID = 1 (same as in Access-Request)
3775
16 Response Authenticator
3778
6 Service-Type (6) = Framed (2)
3779
6 Framed-Protocol (7) = PPP (1)
3780
6 Framed-IP-Address (8) = 255.255.255.254
3781
6 Framed-Routing (10) = None (0)
3782
6 Framed-Compression (13) = VJ TCP/IP Header Compression (1)
3783
6 Framed-MTU (12) = 1500
3785
7.3. User with Challenge-Response card
3787
The NAS at 192.168.1.16 sends an Access-Request UDP packet to the
3788
RADIUS Server for a user named mopsy logging in on port 7. The user
3789
enters the dummy password "challenge" in this example. The challenge
3790
and response generated by the smart card for this example are
3791
"32769430" and "99101462".
3793
The Request Authenticator is a 16 octet random number generated by
3796
The User-Password is 16 octets of password, in this case "challenge",
3797
padded at the end with nulls, XORed with MD5(shared secret|Request
3800
01 02 00 39 f3 a4 7a 1f 6a 6d 76 71 0b 94 7a b9
3801
30 41 a0 39 01 07 6d 6f 70 73 79 02 12 33 65 75
3802
73 77 82 89 b5 70 88 5e 15 08 48 25 c5 04 06 c0
3803
a8 01 10 05 06 00 00 00 07
3810
Rigney, et al. Standards Track [Page 68]
3812
RFC 2865 RADIUS June 2000
3815
1 Code = Access-Request (1)
3818
16 Request Authenticator
3821
7 User-Name (1) = "mopsy"
3822
18 User-Password (2)
3823
6 NAS-IP-Address (4) = 192.168.1.16
3826
The RADIUS server decides to challenge mopsy, sending back a
3827
challenge string and looking for a response. The RADIUS server
3828
therefore and sends an Access-Challenge UDP packet to the NAS.
3830
The Response Authenticator is a 16-octet MD5 checksum of the code
3831
(11), id (2), length (78), the Request Authenticator from above, the
3832
attributes in this reply, and the shared secret.
3834
The Reply-Message is "Challenge 32769430. Enter response at prompt."
3836
The State is a magic cookie to be returned along with user's
3837
response; in this example 8 octets of data (33 32 37 36 39 34 33 30
3840
0b 02 00 4e 36 f3 c8 76 4a e8 c7 11 57 40 3c 0c
3841
71 ff 9c 45 12 30 43 68 61 6c 6c 65 6e 67 65 20
3842
33 32 37 36 39 34 33 30 2e 20 20 45 6e 74 65 72
3843
20 72 65 73 70 6f 6e 73 65 20 61 74 20 70 72 6f
3844
6d 70 74 2e 18 0a 33 32 37 36 39 34 33 30
3846
1 Code = Access-Challenge (11)
3847
1 ID = 2 (same as in Access-Request)
3849
16 Response Authenticator
3852
48 Reply-Message (18)
3855
The user enters his response, and the NAS send a new Access-Request
3856
with that response, and includes the State Attribute.
3858
The Request Authenticator is a new 16 octet random number.
3860
The User-Password is 16 octets of the user's response, in this case
3861
"99101462", padded at the end with nulls, XORed with MD5(shared
3862
secret|Request Authenticator).
3866
Rigney, et al. Standards Track [Page 69]
3868
RFC 2865 RADIUS June 2000
3871
The state is the magic cookie from the Access-Challenge packet,
3874
01 03 00 43 b1 22 55 6d 42 8a 13 d0 d6 25 38 07
3875
c4 57 ec f0 01 07 6d 6f 70 73 79 02 12 69 2c 1f
3876
20 5f c0 81 b9 19 b9 51 95 f5 61 a5 81 04 06 c0
3877
a8 01 10 05 06 00 00 00 07 18 10 33 32 37 36 39
3880
1 Code = Access-Request (1)
3881
1 ID = 3 (Note that this changes.)
3883
16 Request Authenticator
3886
7 User-Name = "mopsy"
3888
6 NAS-IP-Address (4) = 192.168.1.16
3892
The Response was incorrect (for the sake of example), so the RADIUS
3893
server tells the NAS to reject the login attempt.
3895
The Response Authenticator is a 16 octet MD5 checksum of the code
3896
(3), id (3), length(20), the Request Authenticator from above, the
3897
attributes in this reply (in this case, none), and the shared secret.
3899
03 03 00 14 a4 2f 4f ca 45 91 6c 4e 09 c8 34 0f
3902
1 Code = Access-Reject (3)
3903
1 ID = 3 (same as in Access-Request)
3905
16 Response Authenticator
3908
(none, although a Reply-Message could be sent)
3922
Rigney, et al. Standards Track [Page 70]
3924
RFC 2865 RADIUS June 2000
3927
8. Security Considerations
3929
Security issues are the primary topic of this document.
3931
In practice, within or associated with each RADIUS server, there is a
3932
database which associates "user" names with authentication
3933
information ("secrets"). It is not anticipated that a particular
3934
named user would be authenticated by multiple methods. This would
3935
make the user vulnerable to attacks which negotiate the least secure
3936
method from among a set. Instead, for each named user there should
3937
be an indication of exactly one method used to authenticate that user
3938
name. If a user needs to make use of different authentication
3939
methods under different circumstances, then distinct user names
3940
SHOULD be employed, each of which identifies exactly one
3941
authentication method.
3943
Passwords and other secrets should be stored at the respective ends
3944
such that access to them is as limited as possible. Ideally, the
3945
secrets should only be accessible to the process requiring access in
3946
order to perform the authentication.
3948
The secrets should be distributed with a mechanism that limits the
3949
number of entities that handle (and thus gain knowledge of) the
3950
secret. Ideally, no unauthorized person should ever gain knowledge
3951
of the secrets. It is possible to achieve this with SNMP Security
3952
Protocols [14], but such a mechanism is outside the scope of this
3955
Other distribution methods are currently undergoing research and
3956
experimentation. The SNMP Security document [14] also has an
3957
excellent overview of threats to network protocols.
3959
The User-Password hiding mechanism described in Section 5.2 has not
3960
been subjected to significant amounts of cryptanalysis in the
3961
published literature. Some in the IETF community are concerned that
3962
this method might not provide sufficient confidentiality protection
3963
[15] to passwords transmitted using RADIUS. Users should evaluate
3964
their threat environment and consider whether additional security
3965
mechanisms should be employed.
3969
The following changes have been made from RFC 2138:
3971
Strings should use UTF-8 instead of US-ASCII and should be handled as
3974
Integers and dates are now defined as 32 bit unsigned values.
3978
Rigney, et al. Standards Track [Page 71]
3980
RFC 2865 RADIUS June 2000
3983
Updated list of attributes that can be included in Access-Challenge
3984
to be consistent with the table of attributes.
3986
User-Name mentions Network Access Identifiers.
3988
User-Name may now be sent in Access-Accept for use with accounting
3991
Values added for Service-Type, Login-Service, Framed-Protocol,
3992
Framed-Compression, and NAS-Port-Type.
3994
NAS-Port can now use all 32 bits.
3996
Examples now include hexadecimal displays of the packets.
3998
Source UDP port must be used in conjunction with the Request
3999
Identifier when identifying duplicates.
4001
Multiple subattributes may be allowed in a Vendor-Specific attribute.
4003
An Access-Request is now required to contain either a NAS-IP-Address
4004
or NAS-Identifier (or may contain both).
4006
Added notes under "Operations" with more information on proxy,
4007
retransmissions, and keep-alives.
4009
If multiple Attributes with the same Type are present, the order of
4010
Attributes with the same Type MUST be preserved by any proxies.
4012
Clarified Proxy-State.
4014
Clarified that Attributes must not depend on position within the
4015
packet, as long as Attributes of the same type are kept in order.
4017
Added IANA Considerations section.
4019
Updated section on "Proxy" under "Operations".
4021
Framed-MTU can now be sent in Access-Request as a hint.
4023
Updated Security Considerations.
4025
Text strings identified as a subset of string, to clarify use of
4034
Rigney, et al. Standards Track [Page 72]
4036
RFC 2865 RADIUS June 2000
4041
[1] Rigney, C., Rubens, A., Simpson, W. and S. Willens, "Remote
4042
Authentication Dial In User Service (RADIUS)", RFC 2138, April
4045
[2] Bradner, S., "Key words for use in RFCs to Indicate Requirement
4046
Levels", BCP 14, RFC 2119, March, 1997.
4048
[3] Rivest, R. and S. Dusse, "The MD5 Message-Digest Algorithm",
4049
RFC 1321, April 1992.
4051
[4] Postel, J., "User Datagram Protocol", STD 6, RFC 768, August
4054
[5] Rigney, C., "RADIUS Accounting", RFC 2866, June 2000.
4056
[6] Reynolds, J. and J. Postel, "Assigned Numbers", STD 2, RFC
4059
[7] Yergeau, F., "UTF-8, a transformation format of ISO 10646", RFC
4062
[8] Aboba, B. and M. Beadles, "The Network Access Identifier", RFC
4065
[9] Kaufman, C., Perlman, R., and Speciner, M., "Network Security:
4066
Private Communications in a Public World", Prentice Hall, March
4067
1995, ISBN 0-13-061466-1.
4069
[10] Jacobson, V., "Compressing TCP/IP headers for low-speed serial
4070
links", RFC 1144, February 1990.
4072
[11] ISO 8859. International Standard -- Information Processing --
4073
8-bit Single-Byte Coded Graphic Character Sets -- Part 1: Latin
4074
Alphabet No. 1, ISO 8859-1:1987.
4076
[12] Sklower, K., Lloyd, B., McGregor, G., Carr, D. and T.
4077
Coradetti, "The PPP Multilink Protocol (MP)", RFC 1990, August
4080
[13] Alvestrand, H. and T. Narten, "Guidelines for Writing an IANA
4081
Considerations Section in RFCs", BCP 26, RFC 2434, October
4084
[14] Galvin, J., McCloghrie, K. and J. Davin, "SNMP Security
4085
Protocols", RFC 1352, July 1992.
4090
Rigney, et al. Standards Track [Page 73]
4092
RFC 2865 RADIUS June 2000
4095
[15] Dobbertin, H., "The Status of MD5 After a Recent Attack",
4096
CryptoBytes Vol.2 No.2, Summer 1996.
4098
11. Acknowledgements
4100
RADIUS was originally developed by Steve Willens of Livingston
4101
Enterprises for their PortMaster series of Network Access Servers.
4105
The working group can be contacted via the current chair:
4108
Livingston Enterprises
4110
Pleasanton, California 94588
4112
Phone: +1 925 737 2100
4113
EMail: cdr@telemancy.com
4146
Rigney, et al. Standards Track [Page 74]
4148
RFC 2865 RADIUS June 2000
4151
13. Authors' Addresses
4153
Questions about this memo can also be directed to:
4156
Livingston Enterprises
4158
Pleasanton, California 94588
4160
Phone: +1 925 737 2100
4161
EMail: cdr@telemancy.com
4167
Ann Arbor, Michigan 48105-2785
4169
EMail: acr@merit.edu
4172
William Allen Simpson
4174
Computer Systems Consulting Services
4176
Madison Heights, Michigan 48071
4178
EMail: wsimpson@greendragon.com
4182
Livingston Enterprises
4184
Pleasanton, California 94588
4186
EMail: steve@livingston.com
4202
Rigney, et al. Standards Track [Page 75]
4204
RFC 2865 RADIUS June 2000
4207
14. Full Copyright Statement
4209
Copyright (C) The Internet Society (2000). All Rights Reserved.
4211
This document and translations of it may be copied and furnished to
4212
others, and derivative works that comment on or otherwise explain it
4213
or assist in its implementation may be prepared, copied, published
4214
and distributed, in whole or in part, without restriction of any
4215
kind, provided that the above copyright notice and this paragraph are
4216
included on all such copies and derivative works. However, this
4217
document itself may not be modified in any way, such as by removing
4218
the copyright notice or references to the Internet Society or other
4219
Internet organizations, except as needed for the purpose of
4220
developing Internet standards in which case the procedures for
4221
copyrights defined in the Internet Standards process must be
4222
followed, or as required to translate it into languages other than
4225
The limited permissions granted above are perpetual and will not be
4226
revoked by the Internet Society or its successors or assigns.
4228
This document and the information contained herein is provided on an
4229
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
4230
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
4231
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
4232
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
4233
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
4237
Funding for the RFC Editor function is currently provided by the
4258
Rigney, et al. Standards Track [Page 76]