Network Working Group Editor of this version:

Network Working Group Editor of this version:
Request for Comments: 3417 R. Presuhn
STD: 62 BMC Software, Inc.
Obsoletes: 1906 Authors of previous version:
Category: Standards Track J. Case
SNMP Research, Inc.
K. McCloghrie
Cisco Systems, Inc.
M. Rose
Dover Beach Consulting, Inc.
S. Waldbusser
International Network Services
December 2002

Transport Mappings for
the Simple Network Management Protocol (SNMP)

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 (2002). All Rights Reserved.

Abstract

This document defines the transport of Simple Network Management
Protocol (SNMP) messages over various protocols. This document
obsoletes RFC 1906.

Presuhn, et al. Standards Track [Page 1]

RFC 3417 Transport Mappings for SNMP December 2002

Table of Contents

1. Introduction ................................................ 2
2. Definitions ................................................. 3
3. SNMP over UDP over IPv4 ..................................... 7
3.1. Serialization ............................................. 7
3.2. Well-known Values ......................................... 7
4. SNMP over OSI ............................................... 7
4.1. Serialization ............................................. 7
4.2. Well-known Values ......................................... 8
5. SNMP over DDP ............................................... 8
5.1. Serialization ............................................. 8
5.2. Well-known Values ......................................... 8
5.3. Discussion of AppleTalk Addressing ........................ 9
5.3.1. How to Acquire NBP names ................................ 9
5.3.2. When to Turn NBP names into DDP addresses ............... 10
5.3.3. How to Turn NBP names into DDP addresses ................ 10
5.3.4. What if NBP is broken ................................... 10
6. SNMP over IPX ............................................... 11
6.1. Serialization ............................................. 11
6.2. Well-known Values ......................................... 11
7. Proxy to SNMPv1 ............................................. 12
8. Serialization using the Basic Encoding Rules ................ 12
8.1. Usage Example ............................................. 13
9. Notice on Intellectual Property ............................. 14
10. Acknowledgments ............................................ 14
11. IANA Considerations ........................................ 15
12. Security Considerations .................................... 16
13. References ................................................. 16
13.1. Normative References ..................................... 16
13.2. Informative References ................................... 17
14. Changes from RFC 1906 ...................................... 18
15. Editor's Address ........................................... 18
16. Full Copyright Statement ................................... 19

1. Introduction

For a detailed overview of the documents that describe the current
Internet-Standard Management Framework, please refer to section 7 of
RFC 3410 [RFC3410].

Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. MIB objects are generally
accessed through the Simple Network Management Protocol (SNMP).
Objects in the MIB are defined using the mechanisms defined in the
Structure of Management Information (SMI). This memo specifies a MIB

Presuhn, et al. Standards Track [Page 2]

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module that is compliant to the SMIv2, which is described in STD 58,
RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
[RFC2580].

This document, Transport Mappings for the Simple Network Management
Protocol, defines how the management protocol [RFC3416] may be
carried over a variety of protocol suites. It is the purpose of this
document to define how the SNMP maps onto an initial set of transport
domains. At the time of this writing, work was in progress to define
an IPv6 mapping, described in [RFC3419]. Other mappings may be
defined in the future.

Although several mappings are defined, the mapping onto UDP over IPv4
is the preferred mapping for systems supporting IPv4. Systems
implementing IPv4 MUST implement the mapping onto UDP over IPv4. To
maximize interoperability, systems supporting other mappings SHOULD
also provide for access via the UDP over IPv4 mapping.

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 BCP 14, RFC 2119
[RFC2119].

2. Definitions

SNMPv2-TM DEFINITIONS ::= BEGIN

IMPORTS
MODULE-IDENTITY, OBJECT-IDENTITY,
snmpModules, snmpDomains, snmpProxys
FROM SNMPv2-SMI
TEXTUAL-CONVENTION
FROM SNMPv2-TC;

snmpv2tm MODULE-IDENTITY
LAST-UPDATED "200210160000Z"
ORGANIZATION "IETF SNMPv3 Working Group"
CONTACT-INFO
"WG-EMail: [email protected]
Subscribe: [email protected]

Co-Chair: Russ Mundy
Network Associates Laboratories
postal: 15204 Omega Drive, Suite 300
Rockville, MD 20850-4601
USA
EMail: [email protected]
phone: +1 301 947-7107

Presuhn, et al. Standards Track [Page 3]

RFC 3417 Transport Mappings for SNMP December 2002

Co-Chair: David Harrington
Enterasys Networks
postal: 35 Industrial Way
P. O. Box 5005
Rochester, NH 03866-5005
USA
EMail: [email protected]
phone: +1 603 337-2614

Editor: Randy Presuhn
BMC Software, Inc.
postal: 2141 North First Street
San Jose, CA 95131
USA
EMail: [email protected]
phone: +1 408 546-1006"
DESCRIPTION
"The MIB module for SNMP transport mappings.

Copyright (C) The Internet Society (2002). This
version of this MIB module is part of RFC 3417;
see the RFC itself for full legal notices.
"
REVISION "200210160000Z"
DESCRIPTION
"Clarifications, published as RFC 3417."
REVISION "199601010000Z"
DESCRIPTION
"Clarifications, published as RFC 1906."
REVISION "199304010000Z"
DESCRIPTION
"The initial version, published as RFC 1449."
::= { snmpModules 19 }

-- SNMP over UDP over IPv4

snmpUDPDomain OBJECT-IDENTITY
STATUS current
DESCRIPTION
"The SNMP over UDP over IPv4 transport domain.
The corresponding transport address is of type
SnmpUDPAddress."
::= { snmpDomains 1 }

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RFC 3417 Transport Mappings for SNMP December 2002

SnmpUDPAddress ::= TEXTUAL-CONVENTION
DISPLAY-HINT "1d.1d.1d.1d/2d"
STATUS current
DESCRIPTION
"Represents a UDP over IPv4 address:

octets contents encoding
1-4 IP-address network-byte order
5-6 UDP-port network-byte order
"
SYNTAX OCTET STRING (SIZE (6))

-- SNMP over OSI

snmpCLNSDomain OBJECT-IDENTITY
STATUS current
DESCRIPTION
"The SNMP over CLNS transport domain.
The corresponding transport address is of type
SnmpOSIAddress."
::= { snmpDomains 2 }

snmpCONSDomain OBJECT-IDENTITY
STATUS current
DESCRIPTION
"The SNMP over CONS transport domain.
The corresponding transport address is of type
SnmpOSIAddress."
::= { snmpDomains 3 }

SnmpOSIAddress ::= TEXTUAL-CONVENTION
DISPLAY-HINT "*1x:/1x:"
STATUS current
DESCRIPTION
"Represents an OSI transport-address:

octets contents encoding
1 length of NSAP 'n' as an unsigned-integer
(either 0 or from 3 to 20)
2..(n+1) NSAP concrete binary representation
(n+2)..m TSEL string of (up to 64) octets
"
SYNTAX OCTET STRING (SIZE (1 | 4..85))

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RFC 3417 Transport Mappings for SNMP December 2002

-- SNMP over DDP

snmpDDPDomain OBJECT-IDENTITY
STATUS current
DESCRIPTION
"The SNMP over DDP transport domain. The corresponding
transport address is of type SnmpNBPAddress."
::= { snmpDomains 4 }

SnmpNBPAddress ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"Represents an NBP name:

octets contents encoding
1 length of object 'n' as an unsigned integer
2..(n+1) object string of (up to 32) octets
n+2 length of type 'p' as an unsigned integer
(n+3)..(n+2+p) type string of (up to 32) octets
n+3+p length of zone 'q' as an unsigned integer
(n+4+p)..(n+3+p+q) zone string of (up to 32) octets

For comparison purposes, strings are
case-insensitive. All strings may contain any octet
other than 255 (hex ff)."
SYNTAX OCTET STRING (SIZE (3..99))

-- SNMP over IPX

snmpIPXDomain OBJECT-IDENTITY
STATUS current
DESCRIPTION
"The SNMP over IPX transport domain. The corresponding
transport address is of type SnmpIPXAddress."
::= { snmpDomains 5 }

SnmpIPXAddress ::= TEXTUAL-CONVENTION
DISPLAY-HINT "4x.1x:1x:1x:1x:1x:1x.2d"
STATUS current
DESCRIPTION
"Represents an IPX address:

octets contents encoding
1-4 network-number network-byte order
5-10 physical-address network-byte order
11-12 socket-number network-byte order
"
SYNTAX OCTET STRING (SIZE (12))

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RFC 3417 Transport Mappings for SNMP December 2002

-- for proxy to SNMPv1 (RFC 1157)

rfc1157Proxy OBJECT IDENTIFIER ::= { snmpProxys 1 }

rfc1157Domain OBJECT-IDENTITY
STATUS deprecated
DESCRIPTION
"The transport domain for SNMPv1 over UDP over IPv4.
The corresponding transport address is of type
SnmpUDPAddress."
::= { rfc1157Proxy 1 }

-- ::= { rfc1157Proxy 2 } this OID is obsolete

END

3. SNMP over UDP over IPv4

This is the preferred transport mapping.

3.1. Serialization

Each instance of a message is serialized (i.e., encoded according to
the convention of [BER]) onto a single UDP [RFC768] over IPv4
[RFC791] datagram, using the algorithm specified in Section 8.

3.2. Well-known Values

It is suggested that administrators configure their SNMP entities
supporting command responder applications to listen on UDP port 161.
Further, it is suggested that SNMP entities supporting notification
receiver applications be configured to listen on UDP port 162.

When an SNMP entity uses this transport mapping, it must be capable
of accepting messages up to and including 484 octets in size. It is
recommended that implementations be capable of accepting messages of
up to 1472 octets in size. Implementation of larger values is
encouraged whenever possible.

4. SNMP over OSI

This is an optional transport mapping.

4.1. Serialization

Each instance of a message is serialized onto a single TSDU [IS8072]
[IS8072A] for the OSI Connectionless-mode Transport Service (CLTS),
using the algorithm specified in Section 8.

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RFC 3417 Transport Mappings for SNMP December 2002

4.2. Well-known Values

It is suggested that administrators configure their SNMP entities
supporting command responder applications to listen on transport
selector "snmp-l" (which consists of six ASCII characters), when
using a CL-mode network service to realize the CLTS. Further, it is
suggested that SNMP entities supporting notification receiver
applications be configured to listen on transport selector "snmpt-l"
(which consists of seven ASCII characters, six letters and a hyphen)
when using a CL-mode network service to realize the CLTS. Similarly,
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.

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.

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
[APPLETALK], using the algorithm specified in Section 8.

5.2. Well-known Values

SNMP messages are sent using DDP protocol type 8. SNMP entities
supporting command responder applications listen on DDP socket number
8, while SNMP entities supporting notification receiver applications
listen on DDP socket number 9.

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.

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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.,

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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.

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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.)

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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.

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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: [email protected]

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.

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