Rmon C; Introduction To Rmon - 3Com 4210 PWR Configuration Manual

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Introduction to RMON

Working Mechanism of
RMON

RMON C

ONFIGURATION
Remote monitoring (RMON) is a kind of management information base (MIB)
defined by Internet Engineering Task Force (IETF). It is an important enhancement
made to MIB II standards. RMON is mainly used to monitor the data traffic across a
network segment or even the entire network, and is currently a commonly used
network management standard.
An RMON system comprises of two parts: the network management station
(NMS) and the agents running on network devices. RMON agents operate on
network monitors or network probes to collect and keep track of the statistics of
the traffic across the network segments to which their ports connect, such as the
total number of the packets on a network segment in a specific period of time and
the total number of packets successfully sent to a specific host.
RMON is fully based on SNMP architecture. It is compatible with the current
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SNMP implementations.
RMON enables SNMP to monitor remote network devices more effectively and
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actively, thus providing a satisfactory means of monitoring remote subnets.
With RMON implemented, the communication traffic between NMS and SNMP
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agents can be reduced, thus facilitating the management of large-scale
internetworks.
RMON allows multiple monitors. It can collect data in the following two ways:
Using the dedicated RMON probes. When an RMON system operates in this
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way, the NMS directly obtains management information from the RMON
probes and controls the network resources. In this case, all information in the
RMON MIB can be obtained.
Embedding RMON agents into network devices (such as routers, switches and
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hubs) directly to make the latter capable of RMON probe functions. When an
RMON system operates in this way, the NMS collects network management
information by exchanging information with the SNMP agents using the basic
SNMP commands. However, this way depends on device resources heavily and
an NMS operating in this way can only obtain the information about these four
groups (instead of all the information in the RMON MIB): alarm group, event
group, history group, and statistics group.
The 3Com Switch 4210 implements RMON in the second way. With an RMON
agent embedded, the Switch 4210 can serve as a network device with the RMON
probe function. Through the RMON-capable SNMP agents running on the switch,
an NMS can obtain the information about the total traffic, error statistics and
performance statistics of the network segments to which the ports of the