Internet Group Management Protocol MIB
RFC 2933

Network Working Group K. McCloghrie
Request for Comments: 2933 cisco Systems
Category: Standards Track D. Farinacci
 Procket Networks
 D. Thaler
 Microsoft
 October 2000
 Internet Group Management Protocol MIB
Status of this Memo
 This document specifies an Internet standards track protocol for the
 Internet community, and requests discussion and suggestions for
 improvements. Please refer to the current edition of the "Internet
 Official Protocol Standards" (STD 1) for the standardization state
 and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
 Copyright (C) The Internet Society (2000). All Rights Reserved.
Abstract
 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 objects used for managing the Internet
 Group Management Protocol (IGMP).
Table of Contents
 1 Introduction ................................................ 1
 2 The SNMP Network Management Framework ....................... 2
 3 Overview .................................................... 3
 4 Definitions ................................................. 3
 5 Security Considerations ..................................... 14
 6 Intellectual Property Notice ................................ 15
 7 Acknowledgements ............................................ 15
 8 Authors' Addresses .......................................... 16
 9 References .................................................. 17
 10 Full Copyright Statement .................................... 19
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 objects used for managing the Internet
McCloghrie, et al. Standards Track [Page 1]
RFC 2933 Internet Group Management Protocol MIB October 2000
 Group Management Protocol (IGMP), version 1 [16] or version 2 [17].
 A future version of this MIB will support IGMP version 3 (currently a
 work in progress). All of this MIB module is applicable to IPv4
 multicast routers; a subset is applicable to hosts implementing IGMP.
 Since IGMP is specific to IPv4, this MIB does not support management
 of equivalent functionality for other address families, such as IPv6.
 Such management may be supported by other MIBs.
2. The SNMP Network 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
 STD 16, 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], STD 58, RFC 2579 [6] and STD 58, 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
McCloghrie, et al. Standards Track [Page 2]
RFC 2933 Internet Group Management Protocol MIB October 2000
 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
 This MIB module contains two tables:
 (1) the IGMP Interface Table which contains one row for each
 interface on which IGMP is enabled, and
 (2) the IGMP Cache Table which contains one row for each IP
 multicast group for which there are members on a particular
 interface.
 Both tables are intended to be implemented by hosts and routers, but
 some columnar objects in each table apply only to routers.
4. Definitions
IGMP-STD-MIB DEFINITIONS ::= BEGIN
IMPORTS
 MODULE-IDENTITY, OBJECT-TYPE, mib-2, Counter32, Gauge32,
 Unsigned32, IpAddress, TimeTicks FROM SNMPv2-SMI
 RowStatus, TruthValue FROM SNMPv2-TC
 MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF
 InterfaceIndexOrZero,
 InterfaceIndex FROM IF-MIB;
igmpStdMIB MODULE-IDENTITY
 LAST-UPDATED "200009280000Z" -- September 28, 2000
 ORGANIZATION "IETF IDMR Working Group."
 CONTACT-INFO
 " Dave Thaler
 Microsoft Corporation
 One Microsoft Way
 Redmond, WA 98052-6399
 US
 Phone: +1 425 703 8835
 EMail: dthaler@microsoft.com"
 DESCRIPTION
 "The MIB module for IGMP Management."
 REVISION "200009280000Z" -- September 28, 2000
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RFC 2933 Internet Group Management Protocol MIB October 2000
 DESCRIPTION
 "Initial version, published as RFC 2933."
 ::= { mib-2 85 }
igmpMIBObjects OBJECT IDENTIFIER ::= { igmpStdMIB 1 }
--
-- The IGMP Interface Table
--
igmpInterfaceTable OBJECT-TYPE
 SYNTAX SEQUENCE OF IgmpInterfaceEntry
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "The (conceptual) table listing the interfaces on which IGMP
 is enabled."
 ::= { igmpMIBObjects 1 }
igmpInterfaceEntry OBJECT-TYPE
 SYNTAX IgmpInterfaceEntry
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "An entry (conceptual row) representing an interface on
 which IGMP is enabled."
 INDEX { igmpInterfaceIfIndex }
 ::= { igmpInterfaceTable 1 }
IgmpInterfaceEntry ::= SEQUENCE {
 igmpInterfaceIfIndex InterfaceIndex,
 igmpInterfaceQueryInterval Unsigned32,
 igmpInterfaceStatus RowStatus,
 igmpInterfaceVersion Unsigned32,
 igmpInterfaceQuerier IpAddress,
 igmpInterfaceQueryMaxResponseTime Unsigned32,
 igmpInterfaceQuerierUpTime TimeTicks,
 igmpInterfaceQuerierExpiryTime TimeTicks,
 igmpInterfaceVersion1QuerierTimer TimeTicks,
 igmpInterfaceWrongVersionQueries Counter32,
 igmpInterfaceJoins Counter32,
 igmpInterfaceProxyIfIndex InterfaceIndexOrZero,
 igmpInterfaceGroups Gauge32,
 igmpInterfaceRobustness Unsigned32,
 igmpInterfaceLastMembQueryIntvl Unsigned32
}
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RFC 2933 Internet Group Management Protocol MIB October 2000
igmpInterfaceIfIndex OBJECT-TYPE
 SYNTAX InterfaceIndex
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "The ifIndex value of the interface for which IGMP is
 enabled."
 ::= { igmpInterfaceEntry 1 }
igmpInterfaceQueryInterval OBJECT-TYPE
 SYNTAX Unsigned32
 UNITS "seconds"
 MAX-ACCESS read-create
 STATUS current
 DESCRIPTION
 "The frequency at which IGMP Host-Query packets are
 transmitted on this interface."
 DEFVAL { 125 }
 ::= { igmpInterfaceEntry 2 }
igmpInterfaceStatus OBJECT-TYPE
 SYNTAX RowStatus
 MAX-ACCESS read-create
 STATUS current
 DESCRIPTION
 "The activation of a row enables IGMP on the interface. The
 destruction of a row disables IGMP on the interface."
 ::= { igmpInterfaceEntry 3 }
igmpInterfaceVersion OBJECT-TYPE
 SYNTAX Unsigned32
 MAX-ACCESS read-create
 STATUS current
 DESCRIPTION
 "The version of IGMP which is running on this interface.
 This object can be used to configure a router capable of
 running either value. For IGMP to function correctly, all
 routers on a LAN must be configured to run the same version
 of IGMP on that LAN."
 DEFVAL { 2 }
 ::= { igmpInterfaceEntry 4 }
igmpInterfaceQuerier OBJECT-TYPE
 SYNTAX IpAddress
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The address of the IGMP Querier on the IP subnet to which
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RFC 2933 Internet Group Management Protocol MIB October 2000
 this interface is attached."
 ::= { igmpInterfaceEntry 5 }
igmpInterfaceQueryMaxResponseTime OBJECT-TYPE
 SYNTAX Unsigned32 (0..255)
 UNITS "tenths of seconds"
 MAX-ACCESS read-create
 STATUS current
 DESCRIPTION
 "The maximum query response time advertised in IGMPv2
 queries on this interface."
 DEFVAL { 100 }
 ::= { igmpInterfaceEntry 6 }
igmpInterfaceQuerierUpTime OBJECT-TYPE
 SYNTAX TimeTicks
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The time since igmpInterfaceQuerier was last changed."
 ::= { igmpInterfaceEntry 7 }
igmpInterfaceQuerierExpiryTime OBJECT-TYPE
 SYNTAX TimeTicks
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The amount of time remaining before the Other Querier
 Present Timer expires. If the local system is the querier,
 the value of this object is zero."
 ::= { igmpInterfaceEntry 8 }
igmpInterfaceVersion1QuerierTimer OBJECT-TYPE
 SYNTAX TimeTicks
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The time remaining until the host assumes that there are no
 IGMPv1 routers present on the interface. While this is non-
 zero, the host will reply to all queries with version 1
 membership reports."
 ::= { igmpInterfaceEntry 9 }
igmpInterfaceWrongVersionQueries OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
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RFC 2933 Internet Group Management Protocol MIB October 2000
 "The number of queries received whose IGMP version does not
 match igmpInterfaceVersion, over the lifetime of the row
 entry. IGMP requires that all routers on a LAN be
 configured to run the same version of IGMP. Thus, if any
 queries are received with the wrong version, this indicates
 a configuration error."
 ::= { igmpInterfaceEntry 10 }
igmpInterfaceJoins OBJECT-TYPE
 SYNTAX Counter32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The number of times a group membership has been added on
 this interface; that is, the number of times an entry for
 this interface has been added to the Cache Table. This
 object gives an indication of the amount of IGMP activity
 over the lifetime of the row entry."
 ::= { igmpInterfaceEntry 11 }
igmpInterfaceProxyIfIndex OBJECT-TYPE
 SYNTAX InterfaceIndexOrZero
 MAX-ACCESS read-create
 STATUS current
 DESCRIPTION
 "Some devices implement a form of IGMP proxying whereby
 memberships learned on the interface represented by this
 row, cause IGMP Host Membership Reports to be sent on the
 interface whose ifIndex value is given by this object. Such
 a device would implement the igmpV2RouterMIBGroup only on
 its router interfaces (those interfaces with non-zero
 igmpInterfaceProxyIfIndex). Typically, the value of this
 object is 0, indicating that no proxying is being done."
 DEFVAL { 0 }
 ::= { igmpInterfaceEntry 12 }
igmpInterfaceGroups OBJECT-TYPE
 SYNTAX Gauge32
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The current number of entries for this interface in the
 Cache Table."
 ::= { igmpInterfaceEntry 13 }
igmpInterfaceRobustness OBJECT-TYPE
 SYNTAX Unsigned32 (1..255)
 MAX-ACCESS read-create
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RFC 2933 Internet Group Management Protocol MIB October 2000
 STATUS current
 DESCRIPTION
 "The Robustness Variable allows tuning for the expected
 packet loss on a subnet. If a subnet is expected to be
 lossy, the Robustness Variable may be increased. IGMP is
 robust to (Robustness Variable-1) packet losses."
 DEFVAL { 2 }
 ::= { igmpInterfaceEntry 14 }
igmpInterfaceLastMembQueryIntvl OBJECT-TYPE
 SYNTAX Unsigned32 (0..255)
 UNITS "tenths of seconds"
 MAX-ACCESS read-create
 STATUS current
 DESCRIPTION
 "The Last Member Query Interval is the Max Response Time
 inserted into Group-Specific Queries sent in response to
 Leave Group messages, and is also the amount of time between
 Group-Specific Query messages. This value may be tuned to
 modify the leave latency of the network. A reduced value
 results in reduced time to detect the loss of the last
 member of a group. The value of this object is irrelevant
 if igmpInterfaceVersion is 1."
 DEFVAL { 10 }
 ::= { igmpInterfaceEntry 15 }
--
-- The IGMP Cache Table
--
igmpCacheTable OBJECT-TYPE
 SYNTAX SEQUENCE OF IgmpCacheEntry
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "The (conceptual) table listing the IP multicast groups for
 which there are members on a particular interface."
 ::= { igmpMIBObjects 2 }
igmpCacheEntry OBJECT-TYPE
 SYNTAX IgmpCacheEntry
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "An entry (conceptual row) in the igmpCacheTable."
 INDEX { igmpCacheAddress, igmpCacheIfIndex }
 ::= { igmpCacheTable 1 }
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RFC 2933 Internet Group Management Protocol MIB October 2000
IgmpCacheEntry ::= SEQUENCE {
 igmpCacheAddress IpAddress,
 igmpCacheIfIndex InterfaceIndex,
 igmpCacheSelf TruthValue,
 igmpCacheLastReporter IpAddress,
 igmpCacheUpTime TimeTicks,
 igmpCacheExpiryTime TimeTicks,
 igmpCacheStatus RowStatus,
 igmpCacheVersion1HostTimer TimeTicks
}
igmpCacheAddress OBJECT-TYPE
 SYNTAX IpAddress
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "The IP multicast group address for which this entry
 contains information."
 ::= { igmpCacheEntry 1 }
igmpCacheIfIndex OBJECT-TYPE
 SYNTAX InterfaceIndex
 MAX-ACCESS not-accessible
 STATUS current
 DESCRIPTION
 "The interface for which this entry contains information for
 an IP multicast group address."
 ::= { igmpCacheEntry 2 }
igmpCacheSelf OBJECT-TYPE
 SYNTAX TruthValue
 MAX-ACCESS read-create
 STATUS current
 DESCRIPTION
 "An indication of whether the local system is a member of
 this group address on this interface."
 DEFVAL { true }
 ::= { igmpCacheEntry 3 }
igmpCacheLastReporter OBJECT-TYPE
 SYNTAX IpAddress
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The IP address of the source of the last membership report
 received for this IP Multicast group address on this
 interface. If no membership report has been received, this
 object has the value 0.0.0.0."
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RFC 2933 Internet Group Management Protocol MIB October 2000
 ::= { igmpCacheEntry 4 }
igmpCacheUpTime OBJECT-TYPE
 SYNTAX TimeTicks
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The time elapsed since this entry was created."
 ::= { igmpCacheEntry 5 }
igmpCacheExpiryTime OBJECT-TYPE
 SYNTAX TimeTicks
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The minimum amount of time remaining before this entry will
 be aged out. A value of 0 indicates that the entry is only
 present because igmpCacheSelf is true and that if the router
 left the group, this entry would be aged out immediately.
 Note that some implementations may process membership
 reports from the local system in the same way as reports
 from other hosts, so a value of 0 is not required."
 ::= { igmpCacheEntry 6 }
igmpCacheStatus OBJECT-TYPE
 SYNTAX RowStatus
 MAX-ACCESS read-create
 STATUS current
 DESCRIPTION
 "The status of this entry."
 ::= { igmpCacheEntry 7 }
igmpCacheVersion1HostTimer OBJECT-TYPE
 SYNTAX TimeTicks
 MAX-ACCESS read-only
 STATUS current
 DESCRIPTION
 "The time remaining until the local router will assume that
 there are no longer any IGMP version 1 members on the IP
 subnet attached to this interface. Upon hearing any IGMPv1
 Membership Report, this value is reset to the group
 membership timer. While this time remaining is non-zero,
 the local router ignores any IGMPv2 Leave messages for this
 group that it receives on this interface."
 ::= { igmpCacheEntry 8 }
-- conformance information
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RFC 2933 Internet Group Management Protocol MIB October 2000
igmpMIBConformance
 OBJECT IDENTIFIER ::= { igmpStdMIB 2 }
igmpMIBCompliances
 OBJECT IDENTIFIER ::= { igmpMIBConformance 1 }
igmpMIBGroups OBJECT IDENTIFIER ::= { igmpMIBConformance 2 }
-- compliance statements
igmpV1HostMIBCompliance MODULE-COMPLIANCE
 STATUS current
 DESCRIPTION
 "The compliance statement for hosts running IGMPv1 and
 implementing the IGMP MIB."
 MODULE -- this module
 MANDATORY-GROUPS { igmpBaseMIBGroup }
 OBJECT igmpInterfaceStatus
 MIN-ACCESS read-only
 DESCRIPTION
 "Write access is not required."
 OBJECT igmpCacheStatus
 MIN-ACCESS read-only
 DESCRIPTION
 "Write access is not required."
 ::= { igmpMIBCompliances 1 }
igmpV1RouterMIBCompliance MODULE-COMPLIANCE
 STATUS current
 DESCRIPTION
 "The compliance statement for routers running IGMPv1 and
 implementing the IGMP MIB."
 MODULE -- this module
 MANDATORY-GROUPS { igmpBaseMIBGroup,
 igmpRouterMIBGroup
 }
 OBJECT igmpInterfaceStatus
 MIN-ACCESS read-only
 DESCRIPTION
 "Write access is not required."
 OBJECT igmpCacheStatus
 MIN-ACCESS read-only
 DESCRIPTION
 "Write access is not required."
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RFC 2933 Internet Group Management Protocol MIB October 2000
 ::= { igmpMIBCompliances 2 }
igmpV2HostMIBCompliance MODULE-COMPLIANCE
 STATUS current
 DESCRIPTION
 "The compliance statement for hosts running IGMPv2 and
 implementing the IGMP MIB."
 MODULE -- this module
 MANDATORY-GROUPS { igmpBaseMIBGroup,
 igmpV2HostMIBGroup
 }
 OBJECT igmpInterfaceStatus
 MIN-ACCESS read-only
 DESCRIPTION
 "Write access is not required."
 OBJECT igmpCacheStatus
 MIN-ACCESS read-only
 DESCRIPTION
 "Write access is not required."
 ::= { igmpMIBCompliances 3 }
igmpV2RouterMIBCompliance MODULE-COMPLIANCE
 STATUS current
 DESCRIPTION
 "The compliance statement for routers running IGMPv2 and
 implementing the IGMP MIB."
 MODULE -- this module
 MANDATORY-GROUPS { igmpBaseMIBGroup,
 igmpRouterMIBGroup,
 igmpV2RouterMIBGroup
 }
 OBJECT igmpInterfaceStatus
 MIN-ACCESS read-only
 DESCRIPTION
 "Write access is not required."
 OBJECT igmpCacheStatus
 MIN-ACCESS read-only
 DESCRIPTION
 "Write access is not required."
 ::= { igmpMIBCompliances 4 }
-- units of conformance
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RFC 2933 Internet Group Management Protocol MIB October 2000
igmpBaseMIBGroup OBJECT-GROUP
 OBJECTS { igmpCacheSelf,
 igmpCacheStatus, igmpInterfaceStatus
 }
 STATUS current
 DESCRIPTION
 "The basic collection of objects providing management of
 IGMP version 1 or 2."
 ::= { igmpMIBGroups 1 }
igmpRouterMIBGroup OBJECT-GROUP
 OBJECTS { igmpCacheUpTime, igmpCacheExpiryTime,
 igmpInterfaceJoins, igmpInterfaceGroups,
 igmpCacheLastReporter, igmpInterfaceQuerierUpTime,
 igmpInterfaceQuerierExpiryTime,
 igmpInterfaceQueryInterval
 }
 STATUS current
 DESCRIPTION
 "A collection of additional objects for management of IGMP
 version 1 or 2 in routers."
 ::= { igmpMIBGroups 2 }
igmpV2HostMIBGroup OBJECT-GROUP
 OBJECTS { igmpInterfaceVersion1QuerierTimer }
 STATUS current
 DESCRIPTION
 "A collection of additional objects for management of IGMP
 version 2 in hosts."
 ::= { igmpMIBGroups 3 }
igmpHostOptMIBGroup OBJECT-GROUP
 OBJECTS { igmpCacheLastReporter, igmpInterfaceQuerier }
 STATUS current
 DESCRIPTION
 "A collection of optional objects for IGMP hosts.
 Supporting this group can be especially useful in an
 environment with a router which does not support the IGMP
 MIB."
 ::= { igmpMIBGroups 4 }
igmpV2RouterMIBGroup OBJECT-GROUP
 OBJECTS { igmpInterfaceVersion, igmpInterfaceQuerier,
 igmpInterfaceQueryMaxResponseTime,
 igmpInterfaceRobustness,
 igmpInterfaceWrongVersionQueries,
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RFC 2933 Internet Group Management Protocol MIB October 2000
 igmpInterfaceLastMembQueryIntvl,
 igmpCacheVersion1HostTimer
 }
 STATUS current
 DESCRIPTION
 "A collection of additional objects for management of IGMP
 version 2 in routers."
 ::= { igmpMIBGroups 5 }
igmpV2ProxyMIBGroup OBJECT-GROUP
 OBJECTS { igmpInterfaceProxyIfIndex }
 STATUS current
 DESCRIPTION
 "A collection of additional objects for management of IGMP
 proxy devices."
 ::= { igmpMIBGroups 6 }
END
5. Security Considerations
 This MIB contains readable objects whose values provide information
 related to multicast sessions. Some of these objects could contain
 sensitive information. In particular, the igmpCacheSelf and
 igmpCacheLastReporter can be used to identify machines which are
 listening to a given group address. There are also a number of
 objects that have a MAX-ACCESS clause of read-write and/or read-
 create, which allow an administrator to configure IGMP in the router.
 While unauthorized access to the readable objects is relatively
 innocuous, unauthorized access to the write-able objects could cause
 a denial of service. Hence, the support for SET operations in a
 non-secure environment without proper protection can have a negative
 effect on network operations.
 SNMPv1 by itself is such an insecure environment. Even if the
 network itself is secure (for example by using IPSec), even then,
 there is no control as to who on the secure network is allowed to
 access and SET (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.
McCloghrie, et al. Standards Track [Page 14]
RFC 2933 Internet Group Management Protocol MIB October 2000
 It is then a customer/user responsibility to ensure that the SNMP
 entity giving access to this MIB, is properly configured to give
 access to those objects only to those principals (users) that have
 legitimate rights to access them.
6. Intellectual Property Notice
 The IETF takes no position regarding the validity or scope of any
 intellectual property or other rights that might be claimed to
 pertain to the implementation or use of the technology described in
 this document or the extent to which any license under such rights
 might or might not be available; neither does it represent that it
 has made any effort to identify any such rights. Information on the
 IETF's procedures with respect to rights in standards-track and
 standards-related documentation can be found in BCP-11. Copies of
 claims of rights made available for publication and any assurances of
 licenses to be made available, or the result of an attempt made to
 obtain a general license or permission for the use of such
 proprietary rights by implementers or users of this specification can
 be obtained from the IETF Secretariat.
 The IETF invites any interested party to bring to its attention any
 copyrights, patents or patent applications, or other proprietary
 rights which may cover technology that may be required to practice
 this standard. Please address the information to the IETF Executive
 Director.
7. Acknowledgements
 This MIB module was updated based on feedback from the IETF's Inter-
 Domain Multicast Routing (IDMR) Working Group.
McCloghrie, et al. Standards Track [Page 15]
RFC 2933 Internet Group Management Protocol MIB October 2000
8. Authors' Addresses
 Keith McCloghrie
 cisco Systems, Inc.
 170 West Tasman Drive
 San Jose, CA 95134-1706
 Phone: +1 408 526 5260
 EMail: kzm@cisco.com
 Dino Farinacci
 Procket Networks
 3850 North First Street
 San Jose, CA 95134
 Phone: +1 408-954-7909
 Email: dino@procket.com
 Dave Thaler
 Microsoft Corporation
 One Microsoft Way
 Redmond, WA 48105-6399
 Phone: +1 425 703 8835
 EMail: dthaler@microsoft.com
McCloghrie, et al. Standards Track [Page 16]
RFC 2933 Internet Group Management Protocol MIB October 2000
9. References
 [1] Wijnen, B., Harrington, D. and R. Presuhn, "An Architecture for
 Describing SNMP Management Frameworks", RFC 2571, April 1999.
 [2] Rose, M. and K. McCloghrie, "Structure and Identification of
 Management Information for TCP/IP-based Internets", STD 16, RFC
 1155, May 1990.
 [3] Rose, M. and K. McCloghrie, "Concise MIB Definitions", STD 16,
 RFC 1212, March 1991.
 [4] Rose, M., "A Convention for Defining Traps for use with the
 SNMP", RFC 1215, March 1991.
 [5] 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.
 [6] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose,
 M. and S. Waldbusser, "Textual Conventions for SMIv2", STD 58,
 RFC 2579, April 1999.
 [7] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose,
 M. and S. Waldbusser, "Conformance Statements for SMIv2", STD
 58, RFC 2580, April 1999.
 [8] Case, J., Fedor, M., Schoffstall, M. and J. Davin, "Simple
 Network Management Protocol", STD 15, RFC 1157, May 1990.
 [9] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
 "Introduction to Community-based SNMPv2", RFC 1901, January
 1996.
 [10] 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.
 [11] Case, J., Harrington D., Presuhn R. and B. Wijnen, "Message
 Processing and Dispatching for the Simple Network Management
 Protocol (SNMP)", RFC 2572, April 1999.
 [12] Blumenthal, U. and B. Wijnen, "User-based Security Model (USM)
 for version 3 of the Simple Network Management Protocol
 (SNMPv3)", RFC 2574, April 1999.
McCloghrie, et al. Standards Track [Page 17]
RFC 2933 Internet Group Management Protocol MIB October 2000
 [13] 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.
 [14] Levi, D., Meyer, P. and B. Stewart, "SNMPv3 Applications", RFC
 2573, April 1999.
 [15] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based Access
 Control Model (VACM) for the Simple Network Management Protocol
 (SNMP)", RFC 2575, April 1999.
 [16] Deering, S., "Host Extensions for IP Multicasting", STD 5, RFC
 1112, August 1989.
 [17] Fenner, W., "Internet Group Management Protocol, Version 2", RFC
 2236, November 1997.
McCloghrie, et al. Standards Track [Page 18]
RFC 2933 Internet Group Management Protocol MIB October 2000
10. Full Copyright Statement
 Copyright (C) The Internet Society (2000). 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 implementation 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.
McCloghrie, et al. Standards Track [Page 19]