1.6. A Brief Introduction to Remote Monitoring (RMON)
Remote Monitoring Version 1
(RMONv1, or RMON)
is defined in RFC 2819; an enhanced version of the standard, called
RMON Version 2 (RMONv2), is defined in RFC 2021. RMONv1 provides the
NMS with packet-level statistics about an entire LAN or WAN. RMONv2
builds on RMONv1 by providing network- and application-level
statistics. These statistics can be gathered in several ways. One way
is to place an RMON probe on every network segment you want to
monitor. Some Cisco routers have limited RMON capabilities built in,
so you can use their functionality to perform minor RMON duties.
Likewise, some 3Com switches implement the full RMON specification
and can be used as full-blown RMON probes.
The RMON MIB was designed to allow an
actual RMON probe to run in an offline mode that allows the probe to
gather statistics about the network it's watching without
requiring an NMS to query it constantly. At some later time, the NMS
can query the probe for the statistics it has been gathering. Another
feature that most probes implement is the ability to set thresholds
for various error conditions and, when a threshold is crossed, alert
the NMS with an SNMP trap. You can find a little more technical
detail about RMON in the next chapter.
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| 1.5. Host Management |  | 1.7. Getting More Information |
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