User Manual

Enterasys X-Pedition User Reference Manual 453
Chapter 26
RMON
Configuration Guide
RMON Overview
You can employ Remote Network Monitoring (RMON) to help monitor traffic at remote points on
the network. With RMON, data collection and processing is done with a remote probe, namely the
XP. The XP also includes RMON agent software that communicates with a network management
station via SNMP. Because information transmits from the XP to the management station only
when required, SNMP traffic on the network and the management station’s processing load are
reduced.
The XP provides support for both RMON 1 and RMON 2 MIBs, as specified in RFCs 1757 and
2021, respectively. While non-RMON SNMP products allow the monitoring and control of specific
network devices, RMON 1 returns statistics on network segments at the MAC layer. RMON 2
collects statistics on network and application layer traffic to show host-to-host connections and the
applications and protocols being used. For example, the RMON 2 network layer matrix MIB group
can show protocol-specific traffic between pairs of systems which can help to diagnose protocol
problems. Note that RMON 2 is not a superset of RMON 1; on the XP, you can configure both
RMON 1 and RMON 2 statistics collection.
Note: RMON1 (RFC1757) statistic accounts for bridged traffic in host and matrix statistics, but
not routed traffic. RMON2 (RFC2021) accounts for routed traffic in host, matrix, and
protocol distribution statistics, but not bridged traffic. This is a hardware limitation.