C H A P T E R55
• Describe the background of Remote Monitoring.
• Describe the nine RMON groups of monitoring.
Remote Monitoring (RMON) is a standard monitoring specification that enables various network
monitors and console systems to exchange network-monitoring data. RMON provides network
administrators with more freedom in selecting network-monitoring probes and consoles with features
that meet their particular networking needs. This chapter provides a brief overview of the RMON
specification, focusing on RMON groups.
The RMON specification defines a set of statistics and functions that can be exchanged between
RMON-compliant console managers and network probes. As such, RMON provides network
administrators with comprehensive network-fault diagnosis, planning, and performance-tuning
RMON was defined by the user community with the help of the Internet Engineering Task Force (IETF).
It became a proposed standard in 1992 as RFC 1271 (for Ethernet). RMON then became a draft standard
in 1995 as RFC 1757, effectively obsoleting RFC 1271.
Figure 55-1 illustrates an RMON probe capable of monitoring an Ethernet segment and transmitting
statistical information back to an RMON-compliant console.
rnetworking Technologies Handbook
Figure 55-1 An RMON Probe Can Send Statistical Information to an RMON Console
RMON delivers information in nine RMON groups of monitoring elements, each providing specific sets
of data to meet common network-monitoring requirements. Each group is optional so that vendors do
not need to support all the groups within the Management Information Base (MIB). Some RMON groups
require support of other RMON groups to function properly. Table 55-1 summarizes the nine monitoring
groups specified in the RFC 1757 Ethernet RMON MIB.
Table 55-1 RMON Monitoring Groups