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⇱ RFC 2621 - RADIUS Accounting Server MIB



Network Working Group G. Zorn
Request for Comments: 2621 B. Aboba
Category: Informational Microsoft
 June 1999


 RADIUS Accounting Server MIB

Status of this Memo

 This memo provides information for the Internet community. This memo
 does not specify an Internet standard of any kind. Distribution of
 this memo is unlimited.

Copyright Notice

 Copyright (C) The Internet Society (1999). All Rights Reserved.

Abstract

 This memo defines a set of extensions which instrument RADIUS
 accounting server functions. These extensions represent a portion of
 the Management Information Base (MIB) for use with network management
 protocols in the Internet community. Using these extensions IP-based
 management stations can manage RADIUS accounting servers.

1. Introduction

 This memo defines a portion of the Management Information Base (MIB)
 for use with network management protocols in the Internet community.
 In particular, it describes managed objects used for managing RADIUS
 accounting servers.

 RADIUS accounting servers are today widely deployed by dialup
 Internet Service Providers, in order to provide accounting services.
 As a result, the effective management of RADIUS accounting servers is
 of considerable importance.

2. The SNMP Management Framework

 The SNMP Management Framework presently consists of five major
 components:

 o An overall architecture, described in RFC 2571 [1].

 o Mechanisms for describing and naming objects and events for the
 purpose of management. The first version of this Structure of
 Management Information (SMI) is called SMIv1 and described in



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 STD 15, RFC 1155 [2], STD 16, RFC 1212 [3] and RFC 1215 [4].
 The second version, called SMIv2, is described in STD 58, RFC
 2578 [5], RFC 2579 [6] and RFC 2580 [7].

 o Message protocols for transferring management information. The
 first version of the SNMP message protocol is called SNMPv1 and
 described in STD 15, RFC 1157 [8]. A second version of the
 SNMP message protocol, which is not an Internet standards
 track protocol, is called SNMPv2c and described in RFC 1901
 [9] and RFC 1906 [10]. The third version of the message
 protocol is called SNMPv3 and described in RFC 1906 [10], RFC
 2572 [11] and RFC 2574 [12].

 o Protocol operations for accessing management information. The
 first set of protocol operations and associated PDU formats is
 described in STD 15, RFC 1157 [8]. A second set of protocol
 operations and associated PDU formats is described in RFC 1905
 [13].

 o A set of fundamental applications described in RFC 2573 [14] and
 the view-based access control mechanism described in RFC 2575
 [15].

 Managed objects are accessed via a virtual information store, termed
 the Management Information Base or MIB. Objects in the MIB are
 defined using the mechanisms defined in the SMI.

 This memo specifies a MIB module that is compliant to the SMIv2. A
 MIB conforming to the SMIv1 can be produced through the appropriate
 translations. The resulting translated MIB must be semantically
 equivalent, except where objects or events are omitted because no
 translation is possible (use of Counter64). Some machine readable
 information in SMIv2 will be converted into textual descriptions in
 SMIv1 during the translation process. However, this loss of machine
 readable information is not considered to change the semantics of the
 MIB.

3. Overview

 The RADIUS accounting protocol, described in [16], distinguishes
 between the client function and the server function. In RADIUS
 accounting, clients send Accounting-Requests, and servers reply with
 Accounting-Responses. Typically NAS devices implement the client
 function, and thus would be expected to implement the RADIUS
 accounting client MIB, while RADIUS accounting servers implement the
 server function, and thus would be expected to implement the RADIUS
 accounting server MIB.




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 However, it is possible for a RADIUS accounting entity to perform
 both client and server functions. For example, a RADIUS proxy may act
 as a server to one or more RADIUS accounting clients, while
 simultaneously acting as an accounting client to one or more
 accounting servers. In such situations, it is expected that RADIUS
 entities combining client and server functionality will support both
 the client and server MIBs.

3.1. Selected objects

 This MIB module contains thirteen scalars as well as a single table:

 (1) the RADIUS Accounting Client Table contains one row for each
 RADIUS accounting client that the server shares a secret with.

 Each entry in the RADIUS Accounting Client Table includes eleven
 columns presenting a view of the activity of the RADIUS accounting
 server.

4. Definitions

RADIUS-ACC-SERVER-MIB DEFINITIONS ::= BEGIN

IMPORTS
 MODULE-IDENTITY, OBJECT-TYPE, OBJECT-IDENTITY,
 Counter32, Integer32,
 IpAddress, TimeTicks, mib-2 FROM SNMPv2-SMI
 SnmpAdminString FROM SNMP-FRAMEWORK-MIB
 MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF;

radiusAccServMIB MODULE-IDENTITY
 LAST-UPDATED "9906110000Z" -- 11 Jun 1999
 ORGANIZATION "IETF RADIUS Working Group."
 CONTACT-INFO
 " Bernard Aboba
 Microsoft
 One Microsoft Way
 Redmond, WA 98052
 US

 Phone: +1 425 936 6605
 EMail: bernarda@microsoft.com"
 DESCRIPTION
 "The MIB module for entities implementing the server
 side of the Remote Access Dialin User Service (RADIUS)
 accounting protocol."
 REVISION "9906110000Z" -- 11 Jun 1999
 DESCRIPTION "Initial version as published in RFC 2621"



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 ::= { radiusAccounting 1 }

radiusMIB OBJECT-IDENTITY
 STATUS current
 DESCRIPTION
 "The OID assigned to RADIUS MIB work by the IANA."
 ::= { mib-2 67 }

radiusAccounting OBJECT IDENTIFIER ::= {radiusMIB 2}

radiusAccServMIBObjects OBJECT IDENTIFIER ::=
 { radiusAccServMIB 1 }

radiusAccServ OBJECT IDENTIFIER ::= { radiusAccServMIBObjects 1 }

radiusAccServIdent OBJECT-TYPE
 SYNTAX SnmpAdminString
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The implementation identification string for the
 RADIUS accounting server software in use on the
 system, for example; `FNS-2.1'"
 ::= {radiusAccServ 1}

radiusAccServUpTime OBJECT-TYPE
 SYNTAX TimeTicks
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "If the server has a persistent state (e.g., a process),
 this value will be the time elapsed (in hundredths of a
 second) since the server process was started.
 For software without persistent state, this value will
 be zero."
 ::= {radiusAccServ 2}

radiusAccServResetTime OBJECT-TYPE
 SYNTAX TimeTicks
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "If the server has a persistent state (e.g., a process)
 and supports a `reset' operation (e.g., can be told to
 re-read configuration files), this value will be the
 time elapsed (in hundredths of a second) since the
 server was `reset.' For software that does not
 have persistence or does not support a `reset' operation,



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 this value will be zero."
 ::= {radiusAccServ 3}

radiusAccServConfigReset OBJECT-TYPE
 SYNTAX INTEGER { other(1),
 reset(2),
 initializing(3),
 running(4)}
 MAX-ACCESS read-write
 STATUS current
 DESCRIPTION
 "Status/action object to reinitialize any persistent
 server state. When set to reset(2), any persistent
 server state (such as a process) is reinitialized as if
 the server had just been started. This value will
 never be returned by a read operation. When read, one
 of the following values will be returned:
 other(1) - server in some unknown state;
 initializing(3) - server (re)initializing;
 running(4) - server currently running."
 ::= {radiusAccServ 4}

-- New Stats proposed by Dale E. Reed Jr (daler@iea.com)

radiusAccServTotalRequests OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of packets received on the
 accounting port."
 ::= { radiusAccServ 5 }

radiusAccServTotalInvalidRequests OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of RADIUS Accounting-Request packets
 received from unknown addresses."
 ::= { radiusAccServ 6 }

radiusAccServTotalDupRequests OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of duplicate RADIUS Accounting-Request



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 packets received."
 ::= { radiusAccServ 7 }

radiusAccServTotalResponses OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of RADIUS Accounting-Response packets sent."
 ::= { radiusAccServ 8 }

radiusAccServTotalMalformedRequests OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of malformed RADIUS Accounting-Request
 packets received. Bad authenticators or unknown
 types are not included as malformed Access-Requests."
 ::= { radiusAccServ 9 }

radiusAccServTotalBadAuthenticators OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of RADIUS Accounting-Request packets
 which contained invalid Signature attributes."
 ::= { radiusAccServ 10 }

radiusAccServTotalPacketsDropped OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of incoming packets silently discarded
 for a reason other than malformed, bad authenticators,
 or unknown types."
 ::= { radiusAccServ 11 }

radiusAccServTotalNoRecords OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of RADIUS Accounting-Request packets
 which were received and responded to but not
 recorded."



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 ::= { radiusAccServ 12 }

radiusAccServTotalUnknownTypes OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of RADIUS packets of unknowntype which
 were received."
 ::= { radiusAccServ 13 }

-- End of new

radiusAccClientTable OBJECT-TYPE
 SYNTAX SEQUENCE OF RadiusAccClientEntry
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "The (conceptual) table listing the RADIUS accounting
 clients with which the server shares a secret."
 ::= { radiusAccServ 14 }

radiusAccClientEntry OBJECT-TYPE
 SYNTAX RadiusAccClientEntry
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "An entry (conceptual row) representing a RADIUS
 accounting client with which the server shares a secret."
 INDEX { radiusAccClientIndex }
 ::= { radiusAccClientTable 1 }

RadiusAccClientEntry ::= SEQUENCE {
 radiusAccClientIndex Integer32,
 radiusAccClientAddress IpAddress,
 radiusAccClientID SnmpAdminString,
 radiusAccServPacketsDropped Counter32,
 radiusAccServRequests Counter32,
 radiusAccServDupRequests Counter32,
 radiusAccServResponses Counter32,
 radiusAccServBadAuthenticators Counter32,
 radiusAccServMalformedRequests Counter32,
 radiusAccServNoRecords Counter32,
 radiusAccServUnknownTypes Counter32
}

radiusAccClientIndex OBJECT-TYPE
 SYNTAX Integer32 (1..2147483647)



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 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "A number uniquely identifying each RADIUS accounting
 client with which this server communicates."
 ::= { radiusAccClientEntry 1 }

radiusAccClientAddress OBJECT-TYPE
 SYNTAX IpAddress
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The NAS-IP-Address of the RADIUS accounting client
 referred to in this table entry."
 ::= { radiusAccClientEntry 2 }

radiusAccClientID OBJECT-TYPE
 SYNTAX SnmpAdminString
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The NAS-Identifier of the RADIUS accounting client
 referred to in this table entry. This is not necessarily
 the same as sysName in MIB II."
 ::= { radiusAccClientEntry 3 }

-- Server Counters
--
-- Requests - DupRequests - BadAuthenticators - MalformedRequests -
-- UnknownTypes - PacketsDropped - Responses = Pending
--
-- Requests - DupRequests - BadAuthenticators - MalformedRequests -
-- UnknownTypes - PacketsDropped - NoRecords = entries logged

radiusAccServPacketsDropped OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of incoming packets received
 from this client and silently discarded
 for a reason other than malformed, bad
 authenticators, or unknown types."
 ::= { radiusAccClientEntry 4 }

radiusAccServRequests OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only



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 STATUS current
 DESCRIPTION
 "The number of packets received from this
 client on the accounting port."
 ::= { radiusAccClientEntry 5 }

radiusAccServDupRequests OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of duplicate RADIUS Accounting-Request
 packets received from this client."
 ::= { radiusAccClientEntry 6 }

radiusAccServResponses OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of RADIUS Accounting-Response packets
 sent to this client."
 ::= { radiusAccClientEntry 7 }

radiusAccServBadAuthenticators OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of RADIUS Accounting-Request packets
 which contained invalid authenticators received
 from this client."
 ::= { radiusAccClientEntry 8 }

radiusAccServMalformedRequests OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of malformed RADIUS Accounting-Request
 packets which were received from this client.
 Bad authenticators and unknown types
 are not included as malformed Accounting-Requests."
 ::= { radiusAccClientEntry 9 }

radiusAccServNoRecords OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only



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 STATUS current
 DESCRIPTION
 "The number of RADIUS Accounting-Request packets
 which were received and responded to but not
 recorded."
 ::= { radiusAccClientEntry 10 }

radiusAccServUnknownTypes OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of RADIUS packets of unknown type which
 were received from this client."
 ::= { radiusAccClientEntry 11 }


-- conformance information

radiusAccServMIBConformance
 OBJECT IDENTIFIER ::= { radiusAccServMIB 2 }
radiusAccServMIBCompliances
 OBJECT IDENTIFIER ::= { radiusAccServMIBConformance 1 }
radiusAccServMIBGroups
 OBJECT IDENTIFIER ::= { radiusAccServMIBConformance 2 }

-- compliance statements

radiusAccServMIBCompliance MODULE-COMPLIANCE
 STATUS current
 DESCRIPTION
 "The compliance statement for accounting servers
 implementing the RADIUS Accounting Server MIB."
 MODULE -- this module
 MANDATORY-GROUPS { radiusAccServMIBGroup }

 OBJECT radiusAccServConfigReset
 WRITE-SYNTAX INTEGER { reset(2) }
 DESCRIPTION "The only SETable value is 'reset' (2)."

 ::= { radiusAccServMIBCompliances 1 }


-- units of conformance

radiusAccServMIBGroup OBJECT-GROUP
 OBJECTS {radiusAccServIdent,
 radiusAccServUpTime,



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 radiusAccServResetTime,
 radiusAccServConfigReset,
 radiusAccServTotalRequests,
 radiusAccServTotalInvalidRequests,
 radiusAccServTotalDupRequests,
 radiusAccServTotalResponses,
 radiusAccServTotalMalformedRequests,
 radiusAccServTotalBadAuthenticators,
 radiusAccServTotalPacketsDropped,
 radiusAccServTotalNoRecords,
 radiusAccServTotalUnknownTypes,
 radiusAccClientAddress,
 radiusAccClientID,
 radiusAccServPacketsDropped,
 radiusAccServRequests,
 radiusAccServDupRequests,
 radiusAccServResponses,
 radiusAccServBadAuthenticators,
 radiusAccServMalformedRequests,
 radiusAccServNoRecords,
 radiusAccServUnknownTypes
 }
 STATUS current
 DESCRIPTION
 "The collection of objects providing management of
 a RADIUS Accounting Server."
 ::= { radiusAccServMIBGroups 1 }

END

5. References

 [] Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture
 for Describing SNMP Management Frameworks", RFC 2571, April
 1999.

 [] Rose, M., and K. McCloghrie, "Structure and Identification of
 Management Information for TCP/IP-based Internets", STD 16, RFC
 1155, May 1990.

 [] Rose, M., and K. McCloghrie, "Concise MIB Definitions", STD 16,
 RFC 1212, March 1991.

 [] Rose, M., "A Convention for Defining Traps for use with the
 SNMP", RFC 1215, Performance Systems International, March 1991.






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 [] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose,
 M. and S. Waldbusser, "Structure of Management Information
 Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.

 [] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose,
 M. and S. Waldbusser, "Textual Conventions for SMIv2", STD 58,
 RFC 2579, April 1999.

 [] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose,
 M. and S. Waldbusser, "Conformance Statements for SMIv2", STD
 58, RFC 2580, April 1999.

 [] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
 Network Management Protocol", STD 15, RFC 1157, May 1990.

 [] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
 "Introduction to Community-based SNMPv2", RFC 1901, January
 1996.

 [] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
 "Transport Mappings for Version 2 of the Simple Network
 Management Protocol (SNMPv2)", RFC 1906, January 1996.

 [] Case, J., Harrington D., Presuhn R., and B. Wijnen, "Message
 Processing and Dispatching for the Simple Network Management
 Protocol (SNMP)", RFC 2572, April 1999.

 [] Blumenthal, U., and B. Wijnen, "User-based Security Model for
 Version 3 of the Simple Network Management Protocol (SNMPv3)",
 RFC 2574, April 1999.

 [] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol
 Operations for Version 2 of the Simple Network Management
 Protocol (SNMPv2)", RFC 1905, January 1996.

 [] Levi, D., Meyer, P., and B. Stewart, "SNMP Applications", RFC
 2573, April 1999.

 [] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based Access
 Control Model for the Simple Network Management Protocol
 (SNMP)", RFC 2575, April 1999.

 [] Rigney, C., "RADIUS Accounting", RFC 2139, April 1997.








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6. Security Considerations

 There are management objects (radiusAccServConfigReset) defined in
 this MIB that have a MAX-ACCESS clause of read-write and/or read-
 create. Such objects may be considered sensitive or vulnerable in
 some network environments. The support for SET operations in a non-
 secure environment without proper protection can have a negative
 effect on network operations.

 There are a number of managed objects in this MIB that may contain
 sensitive information. These are:

 radiusAccClientAddress
 This can be used to determine the address of the RADIUS
 accounting client with which the server is communicating.
 This information could be useful in impersonating the
 client.

 radiusAccClientID This can be used to determine the client ID for the
 accounting client with which the server is communicating.
 This information could be useful in impersonating the
 client.

 It is thus important to control even GET access to these objects and
 possibly to even encrypt the values of these object when sending them
 over the network via SNMP. Not all versions of SNMP provide features
 for such a secure environment.

 SNMPv1 by itself is not a secure environment. Even if the network
 itself is secure (for example by using IPSec), there is no control as
 to who on the secure network is allowed to access and GET/SET
 (read/change/create/delete) the objects in this MIB.

 It is recommended that the implementers consider the security
 features as provided by the SNMPv3 framework. Specifically, the use
 of the User-based Security Model RFC 2574 [12] and the View-based
 Access Control Model RFC 2575 [15] is recommended. Using these
 security features, customer/users can give access to the objects only
 to those principals (users) that have legitimate rights to GET or SET
 (change/create/delete) them.

7. Acknowledgments

 The authors acknowledge the contributions of the RADIUS Working Group
 in the development of this MIB. Thanks to Narendra Gidwani of
 Microsoft, Allan C. Rubens of MERIT, Carl Rigney of Livingston and
 Peter Heitman of American Internet Corporation for useful discussions
 of this problem space.



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8. Authors' Addresses

 Bernard Aboba
 Microsoft Corporation
 One Microsoft Way
 Redmond, WA 98052

 Phone: 425-936-6605
 EMail: bernarda@microsoft.com


 Glen Zorn
 Microsoft Corporation
 One Microsoft Way
 Redmond, WA 98052

 Phone: 425-703-1559
 EMail: glennz@microsoft.com

































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9. Full Copyright Statement

 Copyright (C) The Internet Society (1999). All Rights Reserved.

 This document and translations of it may be copied and furnished to
 others, and derivative works that comment on or otherwise explain it
 or assist in its implmentation may be prepared, copied, published and
 distributed, in whole or in part, without restriction of any kind,
 provided that the above copyright notice and this paragraph are
 included on all such copies and derivative works. However, this
 document itself may not be modified in any way, such as by removing
 the copyright notice or references to the Internet Society or other
 Internet organizations, except as needed for the purpose of
 developing Internet standards in which case the procedures for
 copyrights defined in the Internet Standards process must be
 followed, or as required to translate it into languages other than
 English.

 The limited permissions granted above are perpetual and will not be
 revoked by the Internet Society or its successors or assigns.

 This document and the information contained herein is provided on an
 "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
 TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
 BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
 HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

 Funding for the RFC Editor function is currently provided by the
 Internet Society.



















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