RFC 1089 UNKNOWN MANAGEMENT · NETWORK PROTOCOLS

SNMP over Ethernet

An experimental way to carry SNMP messages directly in Ethernet frames

On rfc-editor.org ↗
PUBLISHED
February 1989
AUTHORS
M. Schoffstall, C. Davin, M. Fedor, J. Case
STREAM
Legacy
OBSOLETED BY
RFC 4789 — SNMP over IEEE 802
ETHERNET TYPE VALUE
33100 (hexadecimal 814C)
NETWORK SCOPE
LAN-based elements
DOI
10.17487/RFC1089

RFC text

Contents
Original text · RFC Editor View on rfc-editor.org ↗
Network Working Group                                  M. Schoffstall
Request for Comments: 1089           Rensselaer Polytechnic Institute
                                                             C. Davin
                                  MIT Laboratory for Computer Science
                                                             M. Fedor
                                                       NYSERNet, Inc.
                                                              J. Case
                                 University of Tennessee at Knoxville
                                                        February 1989


                           SNMP over Ethernet

Status of This Memo

   This memo describes an experimental method by which the Simple
   Network Management Protocol (SNMP) as specified in [1] can be used
   over Ethernet MAC layer framing [2] instead of the Internet UDP/IP
   protocol stack.  This specification is useful for LAN based network
   elements that support no higher layer protocols beyond the MAC sub-
   layer.  Distribution of this memo is unlimited.

Overview and Rational

   SNMP has been successful in managing Internet capable network
   elements which support the protocol stack at least through UDP the
   connectionless Internet transport layer protocol.  As originally
   designed, SNMP is capable of running over any reasonable transport
   mechanism (not necessarily a transport protocol) that supports bi-
   directional flow and addressability.

   Many non-Internet capable network elements are present in local
   networks; for example, repeaters and wiring concentrators.  They
   include both addressability, and programmable intelligence.  These
   devices are widely used and increasingly important yet, for the most
   part, invisible except through proprietary mechanisms.

Specification

   Almost all Internet capable network elements use the same mechanism
   for encapsulation of the Internet protocol stack regardless of
   conformity with the physical characteristics of Ethernet or 802.3,
   this mechanism is specified in [3] and [4].  This specification
   continues that style with the assignment (by XEROX) of 33100
   (hexadecimal 814C) to the Ethernet Type field for SNMP.  The data
   portion of the Ethernet frame would then be a standard SNMP message
   as specified in [1].

References

     [1]  Case, J., Fedor, M., Schoffstall, M., and J. Davin, "A Simple
          Network Management Protocol", RFC-1067, University of
          Tennessee at Knoxville, NYSERNet, Inc., Rensselaer Polytechnic
          Institute, and Proteon, Inc., August 1988.

     [2]  DEC, "The Ethernet - A Local Area Network", Version 2.0,
          Digital Equipment Corporation, Intel Corporation, Xerox
          Corporation.

     [3]  Hornig, C., "A Standard for the Transmission of IP Datagrams
          over Ethernet Networks", RFC-894, Symbolics, April 1984.

     [4]  Postel, J., and J. Reynolds, "A Standard for the Transmission
          of IP Datagrams over IEEE 802 Networks", RFC-1042, USC
          Information Sciences Institute, February 1988.

Authors' Addresses

   Marty Schoffstall
   NYSERNET Inc.
   Rensselaer Technology Park
   165 Jordan Road
   Troy, NY 12180

   Phone: (518) 276-2654

   EMail: schoff@stonewall.nyser.net


   Chuck Davin
   MIT Laboratory for Computer Science, NE43-507
   545 Technology Square
   Cambridge, MA 02139

   Phone: (617) 253-6020

   EMail: jrd@ptt.lcs.mit.edu
   Mark Fedor
   Nysernet, Inc.
   Rensselaer Technology Park
   125 Jordan Road
   Troy, NY 12180
   (518) 283-8860

   Phone: (518) 283-8860

   EMail: fedor@patton.NYSER.NET


   Jeff Case
   University of Tennessee Computing Center
   Associate Director
   200 Stokely Management Center
   Knoxville, TN 37996-0520

   Phone: (615) 974-6721

   EMail: case@UTKUX1.UTK.EDU

ISO Plain Language

On this page
PROBLEMSome local network elements support Ethernet MAC framing but not the UDP/IP protocol stack normally used by SNMP.
MECHANISMThe RFC assigns an Ethernet Type value so an Ethernet frame can carry a standard SNMP message directly.
EXPERIMENTAL STATUSThis experimental method was later replaced by RFC 4789.

§1Managing Devices Without UDP/IP

SNMP had been used to manage network elements that support the protocol stack through UDP. The RFC notes that some local network elements, such as repeaters and wiring concentrators, have addresses and programmable intelligence but do not support higher-layer protocols beyond the Ethernet MAC sublayer.

It describes using Ethernet framing as the transport for SNMP instead of the Internet UDP/IP stack. This is an experimental method for local-area-network elements.

Some network devices can send and receive Ethernet frames but do not run UDP or IP. This method carries management messages directly in those frames.

§2SNMP in an Ethernet Frame

The Ethernet Type field value 33100, hexadecimal 814C, is assigned to SNMP. The data portion of a frame with that type contains a standard SNMP message as specified in RFC 1067.

The RFC changes the encapsulation, not the SNMP message itself. It describes this as continuing the style used for carrying protocol data over Ethernet.

The Ethernet type value tells the receiver that the frame's data contains an SNMP message. The message itself keeps its standard SNMP format.

§3Scope and Status

The method is for LAN-based network elements that support no higher-layer protocol beyond the MAC sublayer. The RFC describes it as experimental and does not define a change to SNMP itself.

The unit metadata records RFC 4789 as the document that later obsoleted RFC 1089.

This RFC proposes an experimental transport for local devices with only MAC-layer support. RFC 4789 later replaced it.

§4References