Allied Telesis AT-8550 - Manual (Page 232)

RMON
13-12
RMON Features
of the Switch
The IETF defines nine groups of Ethernet RMON statistics. The switch
supports the following four of these groups:
❑ Statistics
❑ History
❑ Alarms
❑ Events
This section describes these groups, and discusses how they can be
used.
Statistics. The RMON Ethernet Statistics group provides traffic and
error statistics showing packets, bytes, broadcasts, multicasts, and
errors on a LAN segment or VLAN.
Information from the Statistics group is used to detect changes in
traffic and error patterns in critical areas of the network.
History. The History group provides historical views of network
performance by taking periodic samples of the counters supplied by
the Statistics group. The group features user-defined sample
intervals and bucket counters for complete customization of trend
analysis.
The group is useful for analysis of traffic patterns and trends on a LAN
segment or VLAN, and to establish baseline information indicating
normal operating parameters.
Alarms. The Alarms group provides a versatile, general mechanism
for setting threshold and sampling intervals to generate events on
any RMON variable. Both rising and falling thresholds are supported,
and thresholds can be on the absolute value of a variable or its delta
value. In addition, alarm thresholds may be autocalibrated or set
manually.
Alarms inform you of a network performance problem and can
trigger automated action responses through the Events group.
Events. The Events group creates entries in an event log and/or
sends SNMP traps to the management workstation. An event is
triggered by an RMON alarm. The action taken can be configured to
ignore it, to log the event, to send an SNMP trap to the receivers
listed in the trap receiver table, or to both log and send a trap. The
RMON traps are defined in RFC 1757 for rising and falling thresholds.