beautypg.com

3 introduction to rmon – Accton Technology ES4710BD User Manual

Page 113

background image

112

E

ES4710BD 10 Slots L2/L3/L4 Chassis Switch

Fig 5-1 ASN.1 tree instance

In this figure, the OID of object A is 1.2.1.1. NMS can find this object without ambiguity through

the object’s unique OID to get the standard variable contained in the object. MIB will define a set of

standard variables for monitored network devices according to this structure.

If the variable information inside Agent MIB needs to be browsed, MIB browsing software

needs to be run in NMS, such as the MIB browser included in ECview. MIBs in the Agent usually

consists of public MIB and private MIB. The public MIB contains public network management

information that can be accessed by all NMS; private MIB contains property information specific to

all the devices. Device manufacturer support is required for NMS to browse and manage the private

MIB.

MIB-I [RFC1156] is the first implementation of SNMP public MIB, and was replaced by

MIB-II [RFC1213]. MIB-II expanded MIB-I but kept its OID of MIB tree. MIB-II contains many

sub-trees, referred to as groups. Objects in these groups cover all the functional domains in network

management. NMS obtains corresponding network management information by visiting the MIB of

the SNMP Agent.

ES4710BD can operate as a SNMP Agent, and supports both SNMP v1 and v2c, basic MIB-II,

RMON public MIB and other related public MIBs such as BRIDGE MIB.

5.4.3 Introduction to RMON

RMON is the most important expansion to the standard SNMP basic architecture. RMON is a

set of MIB definitions used to define standard network monitoring functions and interfaces, and

enabling communication between SNMP management terminals and remote monitors. RMON

provides a highly efficient method to monitor actions inside the subnets.

RMON’s MIB consists of 10 groups, ES4710BD support the most frequently used groups: 1, 2,

3, 9