1068 lines
38 KiB
Plaintext
1068 lines
38 KiB
Plaintext
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Network Working Group Editor of this version:
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Request for Comments: 3417 R. Presuhn
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STD: 62 BMC Software, Inc.
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Obsoletes: 1906 Authors of previous version:
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Category: Standards Track J. Case
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SNMP Research, Inc.
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K. McCloghrie
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Cisco Systems, Inc.
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M. Rose
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Dover Beach Consulting, Inc.
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S. Waldbusser
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International Network Services
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December 2002
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Transport Mappings for
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the Simple Network Management Protocol (SNMP)
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Status of this Memo
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This document specifies an Internet standards track protocol for the
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Internet community, and requests discussion and suggestions for
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improvements. Please refer to the current edition of the "Internet
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Official Protocol Standards" (STD 1) for the standardization state
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and status of this protocol. Distribution of this memo is unlimited.
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Copyright Notice
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Copyright (C) The Internet Society (2002). All Rights Reserved.
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Abstract
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This document defines the transport of Simple Network Management
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Protocol (SNMP) messages over various protocols. This document
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obsoletes RFC 1906.
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Presuhn, et al. Standards Track [Page 1]
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RFC 3417 Transport Mappings for SNMP December 2002
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Table of Contents
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1. Introduction ................................................ 2
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2. Definitions ................................................. 3
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3. SNMP over UDP over IPv4 ..................................... 7
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3.1. Serialization ............................................. 7
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3.2. Well-known Values ......................................... 7
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4. SNMP over OSI ............................................... 7
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4.1. Serialization ............................................. 7
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4.2. Well-known Values ......................................... 8
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5. SNMP over DDP ............................................... 8
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5.1. Serialization ............................................. 8
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5.2. Well-known Values ......................................... 8
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5.3. Discussion of AppleTalk Addressing ........................ 9
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5.3.1. How to Acquire NBP names ................................ 9
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5.3.2. When to Turn NBP names into DDP addresses ............... 10
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5.3.3. How to Turn NBP names into DDP addresses ................ 10
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5.3.4. What if NBP is broken ................................... 10
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6. SNMP over IPX ............................................... 11
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6.1. Serialization ............................................. 11
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6.2. Well-known Values ......................................... 11
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7. Proxy to SNMPv1 ............................................. 12
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8. Serialization using the Basic Encoding Rules ................ 12
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8.1. Usage Example ............................................. 13
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9. Notice on Intellectual Property ............................. 14
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10. Acknowledgments ............................................ 14
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11. IANA Considerations ........................................ 15
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12. Security Considerations .................................... 16
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13. References ................................................. 16
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13.1. Normative References ..................................... 16
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13.2. Informative References ................................... 17
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14. Changes from RFC 1906 ...................................... 18
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15. Editor's Address ........................................... 18
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16. Full Copyright Statement ................................... 19
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1. Introduction
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For a detailed overview of the documents that describe the current
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Internet-Standard Management Framework, please refer to section 7 of
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RFC 3410 [RFC3410].
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Managed objects are accessed via a virtual information store, termed
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the Management Information Base or MIB. MIB objects are generally
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accessed through the Simple Network Management Protocol (SNMP).
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Objects in the MIB are defined using the mechanisms defined in the
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Structure of Management Information (SMI). This memo specifies a MIB
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Presuhn, et al. Standards Track [Page 2]
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RFC 3417 Transport Mappings for SNMP December 2002
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module that is compliant to the SMIv2, which is described in STD 58,
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RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
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[RFC2580].
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This document, Transport Mappings for the Simple Network Management
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Protocol, defines how the management protocol [RFC3416] may be
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carried over a variety of protocol suites. It is the purpose of this
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document to define how the SNMP maps onto an initial set of transport
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domains. At the time of this writing, work was in progress to define
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an IPv6 mapping, described in [RFC3419]. Other mappings may be
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defined in the future.
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Although several mappings are defined, the mapping onto UDP over IPv4
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is the preferred mapping for systems supporting IPv4. Systems
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implementing IPv4 MUST implement the mapping onto UDP over IPv4. To
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maximize interoperability, systems supporting other mappings SHOULD
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also provide for access via the UDP over IPv4 mapping.
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The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
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"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
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document are to be interpreted as described in BCP 14, RFC 2119
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[RFC2119].
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2. Definitions
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SNMPv2-TM DEFINITIONS ::= BEGIN
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IMPORTS
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MODULE-IDENTITY, OBJECT-IDENTITY,
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snmpModules, snmpDomains, snmpProxys
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FROM SNMPv2-SMI
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TEXTUAL-CONVENTION
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FROM SNMPv2-TC;
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snmpv2tm MODULE-IDENTITY
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LAST-UPDATED "200210160000Z"
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ORGANIZATION "IETF SNMPv3 Working Group"
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CONTACT-INFO
|
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"WG-EMail: snmpv3@lists.tislabs.com
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Subscribe: snmpv3-request@lists.tislabs.com
|
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Co-Chair: Russ Mundy
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Network Associates Laboratories
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postal: 15204 Omega Drive, Suite 300
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Rockville, MD 20850-4601
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USA
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EMail: mundy@tislabs.com
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phone: +1 301 947-7107
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Presuhn, et al. Standards Track [Page 3]
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RFC 3417 Transport Mappings for SNMP December 2002
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Co-Chair: David Harrington
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Enterasys Networks
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postal: 35 Industrial Way
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P. O. Box 5005
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Rochester, NH 03866-5005
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USA
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EMail: dbh@enterasys.com
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phone: +1 603 337-2614
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Editor: Randy Presuhn
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BMC Software, Inc.
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postal: 2141 North First Street
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San Jose, CA 95131
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USA
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EMail: randy_presuhn@bmc.com
|
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phone: +1 408 546-1006"
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DESCRIPTION
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"The MIB module for SNMP transport mappings.
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Copyright (C) The Internet Society (2002). This
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version of this MIB module is part of RFC 3417;
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see the RFC itself for full legal notices.
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"
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REVISION "200210160000Z"
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DESCRIPTION
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"Clarifications, published as RFC 3417."
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REVISION "199601010000Z"
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DESCRIPTION
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"Clarifications, published as RFC 1906."
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REVISION "199304010000Z"
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DESCRIPTION
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"The initial version, published as RFC 1449."
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::= { snmpModules 19 }
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-- SNMP over UDP over IPv4
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snmpUDPDomain OBJECT-IDENTITY
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STATUS current
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DESCRIPTION
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"The SNMP over UDP over IPv4 transport domain.
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The corresponding transport address is of type
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SnmpUDPAddress."
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::= { snmpDomains 1 }
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Presuhn, et al. Standards Track [Page 4]
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RFC 3417 Transport Mappings for SNMP December 2002
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SnmpUDPAddress ::= TEXTUAL-CONVENTION
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DISPLAY-HINT "1d.1d.1d.1d/2d"
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STATUS current
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DESCRIPTION
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"Represents a UDP over IPv4 address:
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octets contents encoding
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1-4 IP-address network-byte order
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5-6 UDP-port network-byte order
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"
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SYNTAX OCTET STRING (SIZE (6))
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-- SNMP over OSI
|
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snmpCLNSDomain OBJECT-IDENTITY
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STATUS current
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DESCRIPTION
|
|||
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"The SNMP over CLNS transport domain.
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The corresponding transport address is of type
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SnmpOSIAddress."
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::= { snmpDomains 2 }
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snmpCONSDomain OBJECT-IDENTITY
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STATUS current
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DESCRIPTION
|
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"The SNMP over CONS transport domain.
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The corresponding transport address is of type
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SnmpOSIAddress."
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::= { snmpDomains 3 }
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SnmpOSIAddress ::= TEXTUAL-CONVENTION
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DISPLAY-HINT "*1x:/1x:"
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STATUS current
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DESCRIPTION
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"Represents an OSI transport-address:
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octets contents encoding
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1 length of NSAP 'n' as an unsigned-integer
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(either 0 or from 3 to 20)
|
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2..(n+1) NSAP concrete binary representation
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(n+2)..m TSEL string of (up to 64) octets
|
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"
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SYNTAX OCTET STRING (SIZE (1 | 4..85))
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Presuhn, et al. Standards Track [Page 5]
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RFC 3417 Transport Mappings for SNMP December 2002
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-- SNMP over DDP
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snmpDDPDomain OBJECT-IDENTITY
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STATUS current
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DESCRIPTION
|
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"The SNMP over DDP transport domain. The corresponding
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transport address is of type SnmpNBPAddress."
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::= { snmpDomains 4 }
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SnmpNBPAddress ::= TEXTUAL-CONVENTION
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STATUS current
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DESCRIPTION
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"Represents an NBP name:
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octets contents encoding
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1 length of object 'n' as an unsigned integer
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2..(n+1) object string of (up to 32) octets
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n+2 length of type 'p' as an unsigned integer
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(n+3)..(n+2+p) type string of (up to 32) octets
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n+3+p length of zone 'q' as an unsigned integer
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(n+4+p)..(n+3+p+q) zone string of (up to 32) octets
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For comparison purposes, strings are
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case-insensitive. All strings may contain any octet
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other than 255 (hex ff)."
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SYNTAX OCTET STRING (SIZE (3..99))
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-- SNMP over IPX
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snmpIPXDomain OBJECT-IDENTITY
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STATUS current
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DESCRIPTION
|
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"The SNMP over IPX transport domain. The corresponding
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transport address is of type SnmpIPXAddress."
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::= { snmpDomains 5 }
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SnmpIPXAddress ::= TEXTUAL-CONVENTION
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DISPLAY-HINT "4x.1x:1x:1x:1x:1x:1x.2d"
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STATUS current
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DESCRIPTION
|
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"Represents an IPX address:
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octets contents encoding
|
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1-4 network-number network-byte order
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5-10 physical-address network-byte order
|
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11-12 socket-number network-byte order
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"
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SYNTAX OCTET STRING (SIZE (12))
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Presuhn, et al. Standards Track [Page 6]
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RFC 3417 Transport Mappings for SNMP December 2002
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-- for proxy to SNMPv1 (RFC 1157)
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rfc1157Proxy OBJECT IDENTIFIER ::= { snmpProxys 1 }
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rfc1157Domain OBJECT-IDENTITY
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STATUS deprecated
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DESCRIPTION
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"The transport domain for SNMPv1 over UDP over IPv4.
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The corresponding transport address is of type
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SnmpUDPAddress."
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::= { rfc1157Proxy 1 }
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-- ::= { rfc1157Proxy 2 } this OID is obsolete
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END
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3. SNMP over UDP over IPv4
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This is the preferred transport mapping.
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3.1. Serialization
|
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Each instance of a message is serialized (i.e., encoded according to
|
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the convention of [BER]) onto a single UDP [RFC768] over IPv4
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[RFC791] datagram, using the algorithm specified in Section 8.
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3.2. Well-known Values
|
|||
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|
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It is suggested that administrators configure their SNMP entities
|
|||
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supporting command responder applications to listen on UDP port 161.
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|||
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Further, it is suggested that SNMP entities supporting notification
|
|||
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receiver applications be configured to listen on UDP port 162.
|
|||
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|||
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When an SNMP entity uses this transport mapping, it must be capable
|
|||
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of accepting messages up to and including 484 octets in size. It is
|
|||
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recommended that implementations be capable of accepting messages of
|
|||
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up to 1472 octets in size. Implementation of larger values is
|
|||
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encouraged whenever possible.
|
|||
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|||
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4. SNMP over OSI
|
|||
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|
|||
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This is an optional transport mapping.
|
|||
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|
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4.1. Serialization
|
|||
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|
|||
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Each instance of a message is serialized onto a single TSDU [IS8072]
|
|||
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[IS8072A] for the OSI Connectionless-mode Transport Service (CLTS),
|
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using the algorithm specified in Section 8.
|
|||
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|
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|
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|
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Presuhn, et al. Standards Track [Page 7]
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RFC 3417 Transport Mappings for SNMP December 2002
|
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|
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|
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|
4.2. Well-known Values
|
|||
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|
|||
|
It is suggested that administrators configure their SNMP entities
|
|||
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supporting command responder applications to listen on transport
|
|||
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selector "snmp-l" (which consists of six ASCII characters), when
|
|||
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using a CL-mode network service to realize the CLTS. Further, it is
|
|||
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suggested that SNMP entities supporting notification receiver
|
|||
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applications be configured to listen on transport selector "snmpt-l"
|
|||
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(which consists of seven ASCII characters, six letters and a hyphen)
|
|||
|
when using a CL-mode network service to realize the CLTS. Similarly,
|
|||
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when using a CO-mode network service to realize the CLTS, the
|
|||
|
suggested transport selectors are "snmp-o" and "snmpt-o", for command
|
|||
|
responders and notification receivers, respectively.
|
|||
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|
|||
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When an SNMP entity uses this transport mapping, it must be capable
|
|||
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of accepting messages that are at least 484 octets in size.
|
|||
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Implementation of larger values is encouraged whenever possible.
|
|||
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|
|||
|
5. SNMP over DDP
|
|||
|
|
|||
|
This is an optional transport mapping.
|
|||
|
|
|||
|
5.1. Serialization
|
|||
|
|
|||
|
Each instance of a message is serialized onto a single DDP datagram
|
|||
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[APPLETALK], using the algorithm specified in Section 8.
|
|||
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|
|||
|
5.2. Well-known Values
|
|||
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|
|||
|
SNMP messages are sent using DDP protocol type 8. SNMP entities
|
|||
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supporting command responder applications listen on DDP socket number
|
|||
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8, while SNMP entities supporting notification receiver applications
|
|||
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listen on DDP socket number 9.
|
|||
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|
|||
|
Administrators must configure their SNMP entities supporting command
|
|||
|
responder applications to use NBP type "SNMP Agent" (which consists
|
|||
|
of ten ASCII characters) while those supporting notification receiver
|
|||
|
applications must be configured to use NBP type "SNMP Trap Handler"
|
|||
|
(which consists of seventeen ASCII characters).
|
|||
|
|
|||
|
The NBP name for SNMP entities supporting command responders and
|
|||
|
notification receivers should be stable - NBP names should not change
|
|||
|
any more often than the IP address of a typical TCP/IP node. It is
|
|||
|
suggested that the NBP name be stored in some form of stable storage.
|
|||
|
|
|||
|
When an SNMP entity uses this transport mapping, it must be capable
|
|||
|
of accepting messages that are at least 484 octets in size.
|
|||
|
Implementation of larger values is encouraged whenever possible.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 8]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
5.3. Discussion of AppleTalk Addressing
|
|||
|
|
|||
|
The AppleTalk protocol suite has certain features not manifest in the
|
|||
|
TCP/IP suite. AppleTalk's naming strategy and the dynamic nature of
|
|||
|
address assignment can cause problems for SNMP entities that wish to
|
|||
|
manage AppleTalk networks. TCP/IP nodes have an associated IP
|
|||
|
address which distinguishes each from the other. In contrast,
|
|||
|
AppleTalk nodes generally have no such characteristic. The network-
|
|||
|
level address, while often relatively stable, can change at every
|
|||
|
reboot (or more frequently).
|
|||
|
|
|||
|
Thus, when SNMP is mapped over DDP, nodes are identified by a "name",
|
|||
|
rather than by an "address". Hence, all AppleTalk nodes that
|
|||
|
implement this mapping are required to respond to NBP lookups and
|
|||
|
confirms (e.g., implement the NBP protocol stub), which guarantees
|
|||
|
that a mapping from NBP name to DDP address will be possible.
|
|||
|
|
|||
|
In determining the SNMP identity to register for an SNMP entity, it
|
|||
|
is suggested that the SNMP identity be a name which is associated
|
|||
|
with other network services offered by the machine.
|
|||
|
|
|||
|
NBP lookups, which are used to map NBP names into DDP addresses, can
|
|||
|
cause large amounts of network traffic as well as consume CPU
|
|||
|
resources. It is also the case that the ability to perform an NBP
|
|||
|
lookup is sensitive to certain network disruptions (such as zone
|
|||
|
table inconsistencies) which would not prevent direct AppleTalk
|
|||
|
communications between two SNMP entities.
|
|||
|
|
|||
|
Thus, it is recommended that NBP lookups be used infrequently,
|
|||
|
primarily to create a cache of name-to-address mappings. These
|
|||
|
cached mappings should then be used for any further SNMP traffic. It
|
|||
|
is recommended that SNMP entities supporting command generator
|
|||
|
applications should maintain this cache between reboots. This
|
|||
|
caching can help minimize network traffic, reduce CPU load on the
|
|||
|
network, and allow for (some amount of) network trouble shooting when
|
|||
|
the basic name-to-address translation mechanism is broken.
|
|||
|
|
|||
|
5.3.1. How to Acquire NBP names
|
|||
|
|
|||
|
An SNMP entity supporting command generator applications may have a
|
|||
|
pre-configured list of names of "known" SNMP entities supporting
|
|||
|
command responder applications. Similarly, an SNMP entity supporting
|
|||
|
command generator or notification receiver applications might
|
|||
|
interact with an operator. Finally, an SNMP entity supporting
|
|||
|
command generator or notification receiver applications might
|
|||
|
communicate with all SNMP entities supporting command responder or
|
|||
|
notification originator applications in a set of zones or networks.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 9]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
5.3.2. When to Turn NBP names into DDP addresses
|
|||
|
|
|||
|
When an SNMP entity uses a cache entry to address an SNMP packet, it
|
|||
|
should attempt to confirm the validity mapping, if the mapping hasn't
|
|||
|
been confirmed within the last T1 seconds. This cache entry
|
|||
|
lifetime, T1, has a minimum, default value of 60 seconds, and should
|
|||
|
be configurable.
|
|||
|
|
|||
|
An SNMP entity supporting a command generator application may decide
|
|||
|
to prime its cache of names prior to actually communicating with
|
|||
|
another SNMP entity. In general, it is expected that such an entity
|
|||
|
may want to keep certain mappings "more current" than other mappings,
|
|||
|
e.g., those nodes which represent the network infrastructure (e.g.,
|
|||
|
routers) may be deemed "more important".
|
|||
|
|
|||
|
Note that an SNMP entity supporting command generator applications
|
|||
|
should not prime its entire cache upon initialization - rather, it
|
|||
|
should attempt resolutions over an extended period of time (perhaps
|
|||
|
in some pre-determined or configured priority order). Each of these
|
|||
|
resolutions might, in fact, be a wildcard lookup in a given zone.
|
|||
|
|
|||
|
An SNMP entity supporting command responder applications must never
|
|||
|
prime its cache. When generating a response, such an entity does not
|
|||
|
need to confirm a cache entry. An SNMP entity supporting
|
|||
|
notification originator applications should do NBP lookups (or
|
|||
|
confirms) only when it needs to send an SNMP trap or inform.
|
|||
|
|
|||
|
5.3.3. How to Turn NBP names into DDP addresses
|
|||
|
|
|||
|
If the only piece of information available is the NBP name, then an
|
|||
|
NBP lookup should be performed to turn that name into a DDP address.
|
|||
|
However, if there is a piece of stale information, it can be used as
|
|||
|
a hint to perform an NBP confirm (which sends a unicast to the
|
|||
|
network address which is presumed to be the target of the name
|
|||
|
lookup) to see if the stale information is, in fact, still valid.
|
|||
|
|
|||
|
An NBP name to DDP address mapping can also be confirmed implicitly
|
|||
|
using only SNMP transactions. For example, an SNMP entity supporting
|
|||
|
command generator applications issuing a retrieval operation could
|
|||
|
also retrieve the relevant objects from the NBP group [RFC1742] for
|
|||
|
the SNMP entity supporting the command responder application. This
|
|||
|
information can then be correlated with the source DDP address of the
|
|||
|
response.
|
|||
|
|
|||
|
5.3.4. What if NBP is broken
|
|||
|
|
|||
|
Under some circumstances, there may be connectivity between two SNMP
|
|||
|
entities, but the NBP mapping machinery may be broken, e.g.,
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 10]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
o the NBP FwdReq (forward NBP lookup onto local attached network)
|
|||
|
mechanism might be broken at a router on the other entity's
|
|||
|
network; or,
|
|||
|
|
|||
|
o the NBP BrRq (NBP broadcast request) mechanism might be broken at
|
|||
|
a router on the entity's own network; or,
|
|||
|
|
|||
|
o NBP might be broken on the other entity's node.
|
|||
|
|
|||
|
An SNMP entity supporting command generator applications which is
|
|||
|
dedicated to AppleTalk management might choose to alleviate some of
|
|||
|
these failures by directly implementing the router portion of NBP.
|
|||
|
For example, such an entity might already know all the zones on the
|
|||
|
AppleTalk internet and the networks on which each zone appears.
|
|||
|
Given an NBP lookup which fails, the entity could send an NBP FwdReq
|
|||
|
to the network in which the SNMP entity supporting the command
|
|||
|
responder or notification originator application was last located.
|
|||
|
If that failed, the station could then send an NBP LkUp (NBP lookup
|
|||
|
packet) as a directed (DDP) multicast to each network number on that
|
|||
|
network. Of the above (single) failures, this combined approach will
|
|||
|
solve the case where either the local router's BrRq-to-FwdReq
|
|||
|
mechanism is broken or the remote router's FwdReq-to-LkUp mechanism
|
|||
|
is broken.
|
|||
|
|
|||
|
6. SNMP over IPX
|
|||
|
|
|||
|
This is an optional transport mapping.
|
|||
|
|
|||
|
6.1. Serialization
|
|||
|
|
|||
|
Each instance of a message is serialized onto a single IPX datagram
|
|||
|
[NOVELL], using the algorithm specified in Section 8.
|
|||
|
|
|||
|
6.2. Well-known Values
|
|||
|
|
|||
|
SNMP messages are sent using IPX packet type 4 (i.e., Packet Exchange
|
|||
|
Protocol).
|
|||
|
|
|||
|
It is suggested that administrators configure their SNMP entities
|
|||
|
supporting command responder applications to listen on IPX socket
|
|||
|
36879 (900f hexadecimal). Further, it is suggested that those
|
|||
|
supporting notification receiver applications be configured to listen
|
|||
|
on IPX socket 36880 (9010 hexadecimal).
|
|||
|
|
|||
|
When an SNMP entity uses this transport mapping, it must be capable
|
|||
|
of accepting messages that are at least 546 octets in size.
|
|||
|
Implementation of larger values is encouraged whenever possible.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 11]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
7. Proxy to SNMPv1
|
|||
|
|
|||
|
Historically, in order to support proxy to SNMPv1, as defined in
|
|||
|
[RFC2576], it was deemed useful to define a transport domain,
|
|||
|
rfc1157Domain, which indicates the transport mapping for SNMP
|
|||
|
messages as defined in [RFC1157].
|
|||
|
|
|||
|
8. Serialization using the Basic Encoding Rules
|
|||
|
|
|||
|
When the Basic Encoding Rules [BER] are used for serialization:
|
|||
|
|
|||
|
(1) When encoding the length field, only the definite form is used;
|
|||
|
use of the indefinite form encoding is prohibited. Note that
|
|||
|
when using the definite-long form, it is permissible to use
|
|||
|
more than the minimum number of length octets necessary to
|
|||
|
encode the length field.
|
|||
|
|
|||
|
(2) When encoding the value field, the primitive form shall be used
|
|||
|
for all simple types, i.e., INTEGER, OCTET STRING, and OBJECT
|
|||
|
IDENTIFIER (either IMPLICIT or explicit). The constructed form
|
|||
|
of encoding shall be used only for structured types, i.e., a
|
|||
|
SEQUENCE or an IMPLICIT SEQUENCE.
|
|||
|
|
|||
|
(3) When encoding an object whose syntax is described using the
|
|||
|
BITS construct, the value is encoded as an OCTET STRING, in
|
|||
|
which all the named bits in (the definition of) the bitstring,
|
|||
|
commencing with the first bit and proceeding to the last bit,
|
|||
|
are placed in bits 8 (high order bit) to 1 (low order bit) of
|
|||
|
the first octet, followed by bits 8 to 1 of each subsequent
|
|||
|
octet in turn, followed by as many bits as are needed of the
|
|||
|
final subsequent octet, commencing with bit 8. Remaining bits,
|
|||
|
if any, of the final octet are set to zero on generation and
|
|||
|
ignored on receipt.
|
|||
|
|
|||
|
These restrictions apply to all aspects of ASN.1 encoding, including
|
|||
|
the message wrappers, protocol data units, and the data objects they
|
|||
|
contain.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 12]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
8.1. Usage Example
|
|||
|
|
|||
|
As an example of applying the Basic Encoding Rules, suppose one
|
|||
|
wanted to encode an instance of the GetBulkRequest-PDU [RFC3416]:
|
|||
|
|
|||
|
[5] IMPLICIT SEQUENCE {
|
|||
|
request-id 1414684022,
|
|||
|
non-repeaters 1,
|
|||
|
max-repetitions 2,
|
|||
|
variable-bindings {
|
|||
|
{ name sysUpTime,
|
|||
|
value { unSpecified NULL } },
|
|||
|
{ name ipNetToMediaPhysAddress,
|
|||
|
value { unSpecified NULL } },
|
|||
|
{ name ipNetToMediaType,
|
|||
|
value { unSpecified NULL } }
|
|||
|
}
|
|||
|
}
|
|||
|
|
|||
|
Applying the BER, this may be encoded (in hexadecimal) as:
|
|||
|
|
|||
|
[5] IMPLICIT SEQUENCE a5 82 00 39
|
|||
|
INTEGER 02 04 54 52 5d 76
|
|||
|
INTEGER 02 01 01
|
|||
|
INTEGER 02 01 02
|
|||
|
SEQUENCE (OF) 30 2b
|
|||
|
SEQUENCE 30 0b
|
|||
|
OBJECT IDENTIFIER 06 07 2b 06 01 02 01 01 03
|
|||
|
NULL 05 00
|
|||
|
SEQUENCE 30 0d
|
|||
|
OBJECT IDENTIFIER 06 09 2b 06 01 02 01 04 16 01 02
|
|||
|
NULL 05 00
|
|||
|
SEQUENCE 30 0d
|
|||
|
OBJECT IDENTIFIER 06 09 2b 06 01 02 01 04 16 01 04
|
|||
|
NULL 05 00
|
|||
|
|
|||
|
Note that the initial SEQUENCE in this example was not encoded using
|
|||
|
the minimum number of length octets. (The first octet of the length,
|
|||
|
82, indicates that the length of the content is encoded in the next
|
|||
|
two octets.)
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 13]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
9. Notice on Intellectual Property
|
|||
|
|
|||
|
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 implementors 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.
|
|||
|
|
|||
|
10. Acknowledgments
|
|||
|
|
|||
|
This document is the product of the SNMPv3 Working Group. Some
|
|||
|
special thanks are in order to the following Working Group members:
|
|||
|
|
|||
|
Randy Bush
|
|||
|
Jeffrey D. Case
|
|||
|
Mike Daniele
|
|||
|
Rob Frye
|
|||
|
Lauren Heintz
|
|||
|
Keith McCloghrie
|
|||
|
Russ Mundy
|
|||
|
David T. Perkins
|
|||
|
Randy Presuhn
|
|||
|
Aleksey Romanov
|
|||
|
Juergen Schoenwaelder
|
|||
|
Bert Wijnen
|
|||
|
|
|||
|
This version of the document, edited by Randy Presuhn, was initially
|
|||
|
based on the work of a design team whose members were:
|
|||
|
|
|||
|
Jeffrey D. Case
|
|||
|
Keith McCloghrie
|
|||
|
David T. Perkins
|
|||
|
Randy Presuhn
|
|||
|
Juergen Schoenwaelder
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 14]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
The previous versions of this document, edited by Keith McCloghrie,
|
|||
|
was the result of significant work by four major contributors:
|
|||
|
|
|||
|
Jeffrey D. Case
|
|||
|
Keith McCloghrie
|
|||
|
Marshall T. Rose
|
|||
|
Steven Waldbusser
|
|||
|
|
|||
|
Additionally, the contributions of the SNMPv2 Working Group to the
|
|||
|
previous versions are also acknowledged. In particular, a special
|
|||
|
thanks is extended for the contributions of:
|
|||
|
|
|||
|
Alexander I. Alten
|
|||
|
Dave Arneson
|
|||
|
Uri Blumenthal
|
|||
|
Doug Book
|
|||
|
Kim Curran
|
|||
|
Jim Galvin
|
|||
|
Maria Greene
|
|||
|
Iain Hanson
|
|||
|
Dave Harrington
|
|||
|
Nguyen Hien
|
|||
|
Jeff Johnson
|
|||
|
Michael Kornegay
|
|||
|
Deirdre Kostick
|
|||
|
David Levi
|
|||
|
Daniel Mahoney
|
|||
|
Bob Natale
|
|||
|
Brian O'Keefe
|
|||
|
Andrew Pearson
|
|||
|
Dave Perkins
|
|||
|
Randy Presuhn
|
|||
|
Aleksey Romanov
|
|||
|
Shawn Routhier
|
|||
|
Jon Saperia
|
|||
|
Juergen Schoenwaelder
|
|||
|
Bob Stewart
|
|||
|
Kaj Tesink
|
|||
|
Glenn Waters
|
|||
|
Bert Wijnen
|
|||
|
|
|||
|
11. IANA Considerations
|
|||
|
|
|||
|
The SNMPv2-TM MIB module requires the allocation of a single object
|
|||
|
identifier for its MODULE-IDENTITY. IANA has allocated this object
|
|||
|
identifier in the snmpModules subtree, defined in the SNMPv2-SMI MIB
|
|||
|
module.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 15]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
12. Security Considerations
|
|||
|
|
|||
|
SNMPv1 by itself is not a secure 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
|
|||
|
GET/SET (read/change) the objects accessible through a command
|
|||
|
responder application.
|
|||
|
|
|||
|
It is recommended that the implementors consider the security
|
|||
|
features as provided by the SNMPv3 framework. Specifically, the use
|
|||
|
of the User-based Security Model STD 62, RFC 3414 [RFC3414] and the
|
|||
|
View-based Access Control Model STD 62, RFC 3415 [RFC3415] is
|
|||
|
recommended.
|
|||
|
|
|||
|
It is then a customer/user responsibility to ensure that the SNMP
|
|||
|
entity giving access to a MIB is properly configured to give access
|
|||
|
to the objects only to those principals (users) that have legitimate
|
|||
|
rights to indeed GET or SET (change) them.
|
|||
|
|
|||
|
13. References
|
|||
|
|
|||
|
13.1. Normative References
|
|||
|
|
|||
|
[BER] Information processing systems - Open Systems
|
|||
|
Interconnection - Specification of Basic Encoding Rules
|
|||
|
for Abstract Syntax Notation One (ASN.1), International
|
|||
|
Organization for Standardization. International Standard
|
|||
|
8825, December 1987.
|
|||
|
|
|||
|
[IS8072] Information processing systems - Open Systems
|
|||
|
Interconnection - Transport Service Definition,
|
|||
|
International Organization for Standardization.
|
|||
|
International Standard 8072, June 1986.
|
|||
|
|
|||
|
[IS8072A] Information processing systems - Open Systems
|
|||
|
Interconnection - Transport Service Definition - Addendum
|
|||
|
1: Connectionless-mode Transmission, International
|
|||
|
Organization for Standardization. International Standard
|
|||
|
8072/AD 1, December 1986.
|
|||
|
|
|||
|
[RFC768] Postel, J., "User Datagram Protocol", STD 6, RFC 768,
|
|||
|
August 1980.
|
|||
|
|
|||
|
[RFC791] Postel, J., "Internet Protocol", STD 5, RFC 791,
|
|||
|
September 1981.
|
|||
|
|
|||
|
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
|
|||
|
Requirement Levels", BCP 14, RFC 2119, March 1997.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 16]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
[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.
|
|||
|
|
|||
|
[RFC3414] Blumenthal, U. and B. Wijnen, "The User-Based Security
|
|||
|
Model (USM) for Version 3 of the Simple Network
|
|||
|
Management Protocol (SNMPv3)", STD 62, RFC 3414, December
|
|||
|
2002.
|
|||
|
|
|||
|
[RFC3415] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based
|
|||
|
Access Control Model (VACM) for the Simple Network
|
|||
|
Management Protocol (SNMP)", STD 62, RFC 3415, December
|
|||
|
2002.
|
|||
|
|
|||
|
[RFC3416] Presuhn, R., Case, J., McCloghrie, K., Rose, M. and S.
|
|||
|
Waldbusser, "Version 2 of the Protocol Operations for the
|
|||
|
Simple Network Management Protocol (SNMP)", STD 62, RFC
|
|||
|
3416, December 2002.
|
|||
|
|
|||
|
13.2. Informative References
|
|||
|
|
|||
|
[APPLETALK] Sidhu, G., Andrews, R. and A. Oppenheimer, Inside
|
|||
|
AppleTalk (second edition). Addison-Wesley, 1990.
|
|||
|
|
|||
|
[NOVELL] Network System Technical Interface Overview. Novell,
|
|||
|
Inc., June 1989.
|
|||
|
|
|||
|
[RFC1157] Case, J., Fedor, M., Schoffstall, M. and J. Davin,
|
|||
|
"Simple Network Management Protocol", STD 15, RFC 1157,
|
|||
|
May 1990.
|
|||
|
|
|||
|
[RFC1742] Waldbusser, S. and K. Frisa, "AppleTalk Management
|
|||
|
Information Base II", RFC 1742, January 1995.
|
|||
|
|
|||
|
[RFC2576] Frye, R., Levi, D., Routhier, S. and B. Wijnen,
|
|||
|
"Coexistence between Version 1, Version 2, and Version 3
|
|||
|
of the Internet-Standard Network Management Framework",
|
|||
|
RFC 2576, March 2000.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 17]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
[RFC3410] Case, J., Mundy, R., Partain, D. and B. Stewart,
|
|||
|
"Introduction and Applicability Statements for Internet-
|
|||
|
Standard Management Framework", RFC 3410, December 2002.
|
|||
|
|
|||
|
[RFC3419] Daniele, M. and J. Schoenwaelder, "Textual Conventions
|
|||
|
for Transport Addresses", RFC 3419, November 2002.
|
|||
|
|
|||
|
14. Changes from RFC 1906
|
|||
|
|
|||
|
This document differs from RFC 1906 only in editorial improvements.
|
|||
|
The protocol is unchanged.
|
|||
|
|
|||
|
15. Editor's Address
|
|||
|
|
|||
|
Randy Presuhn
|
|||
|
BMC Software, Inc.
|
|||
|
2141 North First Street
|
|||
|
San Jose, CA 95131
|
|||
|
USA
|
|||
|
|
|||
|
Phone: +1 408 546-1006
|
|||
|
EMail: randy_presuhn@bmc.com
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
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|
|||
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|
|||
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|
|||
|
|
|||
|
|
|||
|
|
|||
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|
|||
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|
|||
|
|
|||
|
|
|||
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|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 18]
|
|||
|
|
|||
|
RFC 3417 Transport Mappings for SNMP December 2002
|
|||
|
|
|||
|
|
|||
|
16. Full Copyright Statement
|
|||
|
|
|||
|
Copyright (C) The Internet Society (2002). 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.
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
|
|||
|
Presuhn, et al. Standards Track [Page 19]
|
|||
|
|