Network Working Group B. Haberman Request for Comments: 3019 Nortel Networks Category: Standards Track R. Worzella IBM January 2001 IP Version 6 Management Information Base for The Multicast Listener Discovery Protocol 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 (2001). All Rights Reserved. Abstract This document defines a portion of the Management Information Base (MIB) for use with network management protocols in Internet Protocol Version 6 internets. Specifically, this document is the MIB module that defines managed objects for implementations of the Multicast Listener Discovery Protocol [RFC2710]. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 1. The SNMP Management Framework The SNMP Management Framework presently consists of five major components: An overall architecture, described in RFC 2571 [RFC2571]. 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, Haberman & Worzella Standards Track [Page 1] RFC 3019 MIB for MLD January 2001 RFC 1155 [RFC1155], STD 16, RFC 1212 [RFC1212] and RFC 1215 [RFC1215]. The second version, called SMIv2, is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580]. Message protocols for transferring management information. The first version of the SNMP message protocol is called SNMPv1 and described in STD 15, RFC 1157 [RFC1157]. A second version of the SNMP message protocol, which is not an Internet standards track protocol, is called SNMPv2c and described in RFC 1901 [RFC1901] and RFC 1906 [RFC1906]. The third version of the message protocol is called SNMPv3 and described in RFC 1906 [RFC1906], RFC 2572 [RFC2572] and RFC 2574 [RFC2574]. Protocol operations for accessing management information. The first set of protocol operations and associated PDU formats is described in STD 15, RFC 1157 [RFC1157]. A second set of protocol operations and associated PDU formats is described in RFC 1905 [RFC1905]. A set of fundamental applications described in RFC 2573 [RFC2573] and the view-based access control mechanism described in RFC 2575 [RFC2575]. A more detailed introduction to the current SNMP Management Framework can be found in RFC 2570 [RFC2570]. 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. 2. Overview This MIB module contains two tables: 1. The MLD Interface Table, which contains one row for each interface on which MLD is enabled. Haberman & Worzella Standards Track [Page 2] RFC 3019 MIB for MLD January 2001 2. The MLD Cache Table which contains one row for each IPv6 Multicast group for which there are members on a particular interface. Both tables are intended to be implemented by hosts and routers. Some objects in each table apply to routers only. 3. Definitions IPV6-MLD-MIB DEFINITIONS ::= BEGIN IMPORTS MODULE-IDENTITY, OBJECT-TYPE, Counter32, Gauge32, Unsigned32, TimeTicks, mib-2 FROM SNMPv2-SMI RowStatus, TruthValue FROM SNMPv2-TC InetAddressIPv6 FROM INET-ADDRESS-MIB InterfaceIndex, InterfaceIndexOrZero FROM IF-MIB MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF; mldMIB MODULE-IDENTITY LAST-UPDATED "200101250000Z" -- 25 Jan 2001 ORGANIZATION "IETF IPNGWG Working Group." CONTACT-INFO " Brian Haberman Nortel Networks 4309 Emperor Blvd. Durham, NC 27703 USA Phone: +1 919 992 4439 e-mail: haberman@nortelnetworks.com" DESCRIPTION "The MIB module for MLD Management." REVISION "200101250000Z" -- 25 Jan 2001 DESCRIPTION "Initial version, published as RFC 3019." ::= { mib-2 91 } mldMIBObjects OBJECT IDENTIFIER ::= { mldMIB 1 } -- -- The MLD Interface Table -- mldInterfaceTable OBJECT-TYPE SYNTAX SEQUENCE OF MldInterfaceEntry Haberman & Worzella Standards Track [Page 3] RFC 3019 MIB for MLD January 2001 MAX-ACCESS not-accessible STATUS current DESCRIPTION "The (conceptual) table listing the interfaces on which MLD is enabled." ::= { mldMIBObjects 1 } mldInterfaceEntry OBJECT-TYPE SYNTAX MldInterfaceEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry (conceptual row) representing an interface on which MLD is enabled." INDEX { mldInterfaceIfIndex } ::= { mldInterfaceTable 1 } MldInterfaceEntry ::= SEQUENCE { mldInterfaceIfIndex InterfaceIndex, mldInterfaceQueryInterval Unsigned32, mldInterfaceStatus RowStatus, mldInterfaceVersion Unsigned32, mldInterfaceQuerier InetAddressIPv6, mldInterfaceQueryMaxResponseDelay Unsigned32, mldInterfaceJoins Counter32, mldInterfaceGroups Gauge32, mldInterfaceRobustness Unsigned32, mldInterfaceLastListenQueryIntvl Unsigned32, mldInterfaceProxyIfIndex InterfaceIndexOrZero, mldInterfaceQuerierUpTime TimeTicks, mldInterfaceQuerierExpiryTime TimeTicks } mldInterfaceIfIndex OBJECT-TYPE SYNTAX InterfaceIndex MAX-ACCESS not-accessible STATUS current DESCRIPTION "The internetwork-layer interface value of the interface for which MLD is enabled." ::= { mldInterfaceEntry 1 } mldInterfaceQueryInterval OBJECT-TYPE SYNTAX Unsigned32 UNITS "seconds" MAX-ACCESS read-create STATUS current Haberman & Worzella Standards Track [Page 4] RFC 3019 MIB for MLD January 2001 DESCRIPTION "The frequency at which MLD Host-Query packets are transmitted on this interface." DEFVAL { 125 } ::= { mldInterfaceEntry 2 } mldInterfaceStatus OBJECT-TYPE SYNTAX RowStatus MAX-ACCESS read-create STATUS current DESCRIPTION "The activation of a row enables MLD on the interface. The destruction of a row disables MLD on the interface." ::= { mldInterfaceEntry 3 } mldInterfaceVersion OBJECT-TYPE SYNTAX Unsigned32 MAX-ACCESS read-create STATUS current DESCRIPTION "The version of MLD which is running on this interface. This object is a place holder to allow for new versions of MLD to be introduced. Version 1 of MLD is defined in RFC 2710." DEFVAL { 1 } ::= { mldInterfaceEntry 4 } mldInterfaceQuerier OBJECT-TYPE SYNTAX InetAddressIPv6 (SIZE (16)) MAX-ACCESS read-only STATUS current DESCRIPTION "The address of the MLD Querier on the IPv6 subnet to which this interface is attached." ::= { mldInterfaceEntry 5 } mldInterfaceQueryMaxResponseDelay OBJECT-TYPE SYNTAX Unsigned32 UNITS "seconds" MAX-ACCESS read-create STATUS current DESCRIPTION "The maximum query response time advertised in MLD queries on this interface." DEFVAL { 10 } ::= { mldInterfaceEntry 6 } mldInterfaceJoins OBJECT-TYPE Haberman & Worzella Standards Track [Page 5] RFC 3019 MIB for MLD January 2001 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 MLD activity over time." ::= { mldInterfaceEntry 7 } mldInterfaceGroups OBJECT-TYPE SYNTAX Gauge32 MAX-ACCESS read-only STATUS current DESCRIPTION "The current number of entries for this interface in the Cache Table." ::= { mldInterfaceEntry 8 } mldInterfaceRobustness OBJECT-TYPE SYNTAX Unsigned32 MAX-ACCESS read-create 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. MLD is robust to (Robustness Variable-1) packet losses. The discussion of the Robustness Variable is in Section 7.1 of RFC 2710." DEFVAL { 2 } ::= { mldInterfaceEntry 9 } mldInterfaceLastListenQueryIntvl OBJECT-TYPE SYNTAX Unsigned32 UNITS "seconds" MAX-ACCESS read-create STATUS current DESCRIPTION "The Last Member Query Interval is the Max Response Delay 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." DEFVAL { 1 } Haberman & Worzella Standards Track [Page 6] RFC 3019 MIB for MLD January 2001 ::= { mldInterfaceEntry 10 } mldInterfaceProxyIfIndex OBJECT-TYPE SYNTAX InterfaceIndexOrZero MAX-ACCESS read-create STATUS current DESCRIPTION "Some devices implement a form of MLD proxying whereby memberships learned on the interface represented by this row, cause MLD Multicast Listener Reports to be sent on the internetwork-layer interface identified by this object. Such a device would implement mldRouterMIBGroup only on its router interfaces (those interfaces with non-zero mldInterfaceProxyIfIndex). Typically, the value of this object is 0, indicating that no proxying is being done." DEFVAL { 0 } ::= { mldInterfaceEntry 11 } mldInterfaceQuerierUpTime OBJECT-TYPE SYNTAX TimeTicks MAX-ACCESS read-only STATUS current DESCRIPTION "The time since mldInterfaceQuerier was last changed." ::= { mldInterfaceEntry 12 } mldInterfaceQuerierExpiryTime OBJECT-TYPE SYNTAX TimeTicks MAX-ACCESS read-only STATUS current DESCRIPTION "The time remaining before the Other Querier Present Timer expires. If the local system is the querier, the value of this object is zero." ::= { mldInterfaceEntry 13 } -- -- The MLD Cache Table -- mldCacheTable OBJECT-TYPE SYNTAX SEQUENCE OF MldCacheEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "The (conceptual) table listing the IPv6 multicast Haberman & Worzella Standards Track [Page 7] RFC 3019 MIB for MLD January 2001 groups for which there are members on a particular interface." ::= { mldMIBObjects 2 } mldCacheEntry OBJECT-TYPE SYNTAX MldCacheEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry (conceptual row) in the mldCacheTable." INDEX { mldCacheAddress, mldCacheIfIndex } ::= { mldCacheTable 1 } MldCacheEntry ::= SEQUENCE { mldCacheAddress InetAddressIPv6, mldCacheIfIndex InterfaceIndex, mldCacheSelf TruthValue, mldCacheLastReporter InetAddressIPv6, mldCacheUpTime TimeTicks, mldCacheExpiryTime TimeTicks, mldCacheStatus RowStatus } mldCacheAddress OBJECT-TYPE SYNTAX InetAddressIPv6 (SIZE (16)) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The IPv6 multicast group address for which this entry contains information." ::= { mldCacheEntry 1 } mldCacheIfIndex OBJECT-TYPE SYNTAX InterfaceIndex MAX-ACCESS not-accessible STATUS current DESCRIPTION "The internetwork-layer interface for which this entry contains information for an IPv6 multicast group address." ::= { mldCacheEntry 2 } mldCacheSelf OBJECT-TYPE SYNTAX TruthValue MAX-ACCESS read-create STATUS current DESCRIPTION "An indication of whether the local system is a member of Haberman & Worzella Standards Track [Page 8] RFC 3019 MIB for MLD January 2001 this group address on this interface." DEFVAL { true } ::= { mldCacheEntry 3 } mldCacheLastReporter OBJECT-TYPE SYNTAX InetAddressIPv6 (SIZE (16)) MAX-ACCESS read-only STATUS current DESCRIPTION "The IPv6 address of the source of the last membership report received for this IPv6 Multicast group address on this interface. If no membership report has been received, this object has the value 0::0." ::= { mldCacheEntry 4 } mldCacheUpTime OBJECT-TYPE SYNTAX TimeTicks MAX-ACCESS read-only STATUS current DESCRIPTION "The time elapsed since this entry was created." ::= { mldCacheEntry 5 } mldCacheExpiryTime 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 mldCacheSelf 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." ::= { mldCacheEntry 6 } mldCacheStatus OBJECT-TYPE SYNTAX RowStatus MAX-ACCESS read-create STATUS current DESCRIPTION "The status of this row, by which new entries may be created, or existing entries deleted from this table." ::= { mldCacheEntry 7 } Haberman & Worzella Standards Track [Page 9] RFC 3019 MIB for MLD January 2001 -- conformance information mldMIBConformance OBJECT IDENTIFIER ::= { mldMIB 2 } mldMIBCompliances OBJECT IDENTIFIER ::= { mldMIBConformance 1 } mldMIBGroups OBJECT IDENTIFIER ::= { mldMIBConformance 2 } -- compliance statements mldHostMIBCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for hosts running MLD and implementing the MLD MIB." MODULE -- this module MANDATORY-GROUPS { mldBaseMIBGroup, mldHostMIBGroup } OBJECT mldInterfaceStatus MIN-ACCESS read-only DESCRIPTION "Write access is not required." ::= { mldMIBCompliances 1 } mldRouterMIBCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for routers running MLD and implementing the MLD MIB." MODULE -- this module MANDATORY-GROUPS { mldBaseMIBGroup, mldRouterMIBGroup } OBJECT mldInterfaceStatus MIN-ACCESS read-only DESCRIPTION "Write access is not required." ::= { mldMIBCompliances 2 } -- units of conformance Haberman & Worzella Standards Track [Page 10] RFC 3019 MIB for MLD January 2001 mldBaseMIBGroup OBJECT-GROUP OBJECTS { mldCacheSelf, mldCacheStatus, mldInterfaceStatus } STATUS current DESCRIPTION "The basic collection of objects providing management of MLD. The mldBaseMIBGroup is designed to allow for the manager creation and deletion of MLD cache entries." ::= { mldMIBGroups 1 } mldRouterMIBGroup OBJECT-GROUP OBJECTS { mldCacheUpTime, mldCacheExpiryTime, mldInterfaceQueryInterval, mldInterfaceJoins, mldInterfaceGroups, mldCacheLastReporter, mldInterfaceQuerierUpTime, mldInterfaceQuerierExpiryTime, mldInterfaceQuerier, mldInterfaceVersion, mldInterfaceQueryMaxResponseDelay, mldInterfaceRobustness, mldInterfaceLastListenQueryIntvl } STATUS current DESCRIPTION "A collection of additional objects for management of MLD in routers." ::= { mldMIBGroups 2 } mldHostMIBGroup OBJECT-GROUP OBJECTS { mldInterfaceQuerier } STATUS current DESCRIPTION "A collection of additional objects for management of MLD in hosts." ::= { mldMIBGroups 3 } mldProxyMIBGroup OBJECT-GROUP OBJECTS { mldInterfaceProxyIfIndex } STATUS current DESCRIPTION "A collection of additional objects for management of MLD proxy devices." Haberman & Worzella Standards Track [Page 11] RFC 3019 MIB for MLD January 2001 ::= { mldMIBGroups 4 } END 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 mldCacheSelf and mldCacheLastReporter could 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 MLD 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 of 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 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 [RFC2574] and the View- based Access Control Model RFC 2575 [RFC2575] is recommended. 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. Acknowledgements This MIB module is based on the IGMP MIB authored by Keith McCloghrie, Dino Farinacci, and Dave Thaler. It was updated based on feedback from the IPNGWG working group, Bert Wijnen, Peder Norgaard, and extensive comments from Juergen Schoenwaelder. Haberman & Worzella Standards Track [Page 12] RFC 3019 MIB for MLD January 2001 References [RFC2710] Deering, S., Fenner, W. and B. Haberman, "Multicast Listener Discovery (MLD) for IPv6", RFC 2710, October 1999. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2571] Harrington, D., Presuhn, R. and B. Wijnen, "An Architecture for Describing SNMP Management Frameworks", RFC 2571, April 1999. [RFC1155] Rose, M. and K. McCloghrie, "Structure and Identification of Management Information for TCP/IP-based Internets", STD 16, RFC 1155, May 1990. [RFC1212] Rose, M. and K. McCloghrie, "Concise MIB Definitions", STD 16, RFC 1212, March 1991. [RFC1215] Rose, M., "A Convention for Defining Traps for use with the SNMP", RFC 1215, March 1991. [RFC2578] 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. [RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999. [RFC1157] Case, J., Fedor, M., Schoffstall, M. and J. Davin, "Simple Network Management Protocol", STD 15, RFC 1157, May 1990. [RFC1901] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser, "Introduction to Community-based SNMPv2", RFC 1901, January 1996. [RFC1906] 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. Haberman & Worzella Standards Track [Page 13] RFC 3019 MIB for MLD January 2001 [RFC2572] Case, J., Harrington D., Presuhn R. and B. Wijnen, "Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)", RFC 2572, April 1999. [RFC2574] Blumenthal, U. and B. Wijnen, "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", RFC 2574, April 1999. [RFC1905] 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. [RFC2573] Levi, D., Meyer, P. and B. Stewart, "SNMPv3 Applications", RFC 2573, April 1999. [RFC2575] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", RFC 2575, April 1999. [RFC2570] Case, J., Mundy, R., Partain, D. and B. Stewart, "Introduction to Version 3 of the Internet-standard Network Management Framework", RFC 2570, April 1999. Authors' Addresses Brian Haberman Nortel Networks 4309 Emperor Blvd. Suite 200 Durham, NC 27703 USA Phone: +1-919-992-4439 EMail: haberman@nortelnetworks.com Randy Worzella IBM Corporation 800 Park Office Drive Research Triangle Park, NC 27709 USA Phone: +1-919-254-2202 EMail: worzella@us.ibm.com Haberman & Worzella Standards Track [Page 14] RFC 3019 MIB for MLD January 2001 Full Copyright Statement Copyright (C) The Internet Society (2001). 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. Haberman & Worzella Standards Track [Page 15]