Overview of RMON

RMON is implemented based on the SNMP architecture and shares a set of Network Management Station (NMS) with SNMP to remotely manage devices.

The RMON standard (RFC2819) defines multiple RMON groups, and the device implements the four groups supported in public MIBs: statistics, history, alarms, and events, achieving the following four statistics and alarm functions for remote monitoring and management of devices in the network.

• Ethernet statistics function (etherStatsTable in RMON MIB): the basic statistics of each network being monitored. The system continuously gathers statistics for the traffic and the distribution of various types of packets like broadcast and multicast, the number of collisions, the number of CRC checksum error messages, the number of undersized (or oversized) data messages, and the number of received bytes and dropped packets.
• History statistics function (etherHistoryTable in RMON MIB): The system periodically samples, collects and stores the network statistics information. The statistics include bandwidth utilization, number of error packets and total packets, etc.
• Event definition function (eventTable and logTable in RMON MIB): The event group controls the events and prompts coming from the device, providing information about all events generated by RMON agent. When an event occurs, a log can be recorded or a trap can be sent to the network management station.
• Alarm threshold setting function (alarmTable in RMON MIB): The system monitors the specified alarm variable (alarm object corresponding to the SNMP OID). The RMON agent will record the monitored status as a log or send the trap to the network management station.