Cabletron Systems ELS10-26 Network Router User Manual


 
Introduction
1-5
1.4 SNMP PRIMITIVES
The major software interface between the NMS and ELS10-26
consists of one simple mechanism – the exchange of SNMP (Simple
Network Management Protocol, RFC 1157) datagrams over any
available physical media. The following restrictions apply:
All datagrams must obey SNMP format.
All datagrams must be sent via UDP and IP. Thus, all datagrams
will have UDP and IP headers.
Datagrams may be sent over any of the following physical
media:
- Ethernet/802.3 LAN - the datagram must have an Ethernet
MAC header, with an Ethernet frame type of IP; or, the
datagram must be in 802.3 format with IP-encapsulation as
defined by RFC 1042.
- UART (out-of-band management port) - the datagram must
have a PPP header, which indicates that the datagram
contains an IP packet. (The ELS10-26 automatically detects
the presence of a PPP connection versus being connected to
a non-intelligent terminal.)
The NMS must rely on IP, rather than MAC addressing for all
datagrams sent to an ELS10-26. Therefore:
All datagrams from the ELS10-26 are addressed to either an
NMS or the broadcast IP address.
Within the context of this document, the terms “datagram,”
“packet,” and “PDU” are synonymous.