IP Version 6 Management Information Base for The Multicast Listener Discovery Protocol
RFC 3019

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,
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 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.
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 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
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 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
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 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
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 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 }
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 ::= { 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
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 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
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 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 }
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 -- 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
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 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."
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 ::= { 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.
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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
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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.
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 "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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