RFC 1298 (rfc1298) - Page 2 of 5
SNMP over IPX
Alternative Format: Original Text Document
RFC 1298 SNMP over IPX February 1992
available. SNMP implementors should be aware that the choice of
underlying transport may have a significant impact on the
interoperability and ubiquity of the management capability in the
Internet. Considerations relevant to choosing a transport for use
with SNMP are described in [5].
2. Specification
SNMP packets will always set the Packet Type field in the IPX header
to 4 (i.e., Packet Exchange Packet).
2.1 Socket Assignments
SNMP protocol entities will receive GetRequest-PDU, GetNextRequest-
PDU, and SetRequest-PDU messages on socket 36879 (Destination Socket
field set to hexadecimal 900F), and Trap-PDU messages on socket 36880
(Destination Socket field set to hexadecimal 9010).
GetResponse-PDU messages will be addressed to the IPX address and
socket from which the corresponding GetRequest-PDU, GetNextRequest-
PDU, or SetRequest-PDU originated.
2.2 Maximum Packet Length
Although SNMP does not require conformant implementations to accept
messages whose length exceed 484 bytes, it is recommended that
implementations support a maximum SNMP message size of 546 bytes (the
maximum size allowed under IPX). Furthermore, this limit is the
maximum packet length guaranteed to traverse IPX routers which do not
provide fragmentation. Implementors may choose to use longer packet
lengths if the maximum is known, which depends on the intermediate
routers and/or intermediate datalink layer protocols.
2.3 The agent-addr Field for the Trap-PDU
The agent-addr field in a Trap-PDU emitted by an SNMP agent should
contain the IpAddress 0.0.0.0. An SNMP manager may ascertain the
source of the trap by querying the transport layer.
2.4 IPX Transport Address Representation
There are occasions when it is necessary to represent a transport
service address in a MIB. For instance, the SNMP party MIB [6] uses
an OBJECT IDENTIFIER to define the transport domain (IP, IPX, etc.)
and an OCTET STRING to represent an address within that domain. The
following definitions are provided for use in such a scheme.
Wormley & Bostock