Cisco WS-C2980G-A Software Guide - Page 371

Chapter 24 Configuring SNMP Understanding How SNMP Works Table 24-1 SNMP Terminology (continued) Term SNMP Version 2c (SNMPv2c) SNMP engine SNMP group SNMP user SNMP view trap write view Definition This second version of SNMP supports centralized and distributed network management strategies and includes improvements in the Structure of Management Information (SMI), protocol operations, management architecture, and security. A copy of SNMP that can reside on the local or remote device. A collection of SNMP users that belong to a common SNMP list that defines an access policy, in which object identification numbers (OIDs) are both read-accessible and write-accessible. Users belonging to a particular SNMP group inherit all of these attributes that are defined by the group. A person for which an SNMP management operation is performed. The user is the person on a remote SNMP engine who receives the inform messages. A mapping between SNMP objects and the access rights available for those objects. An object can have different access rights in each view. Access rights indicate whether the object is accessible by either a community string or a user. A message sent by an SNMP agent to a console or terminal indicates that a significant event occurred. A view name (not to exceed 64 characters) for each group; the view name defines the list of object identifiers (OIDs) that are able to be created or modified by users of the group. Understanding How SNMP Works SNMP is an application-layer protocol that facilitates the exchange of management information between network devices. SNMP enables network administrators to manage network performance, find and solve network problems, and plan for network growth. There are three versions of SNMP: • Version 1 (SNMPv1)-This is the initial implementation of SNMP. Refer to RFC 1157 for a full description of functionality. See the "Understanding How SNMPv1 and SNMPv2c Work" section on page 24-5 for more information on SNMPv1. • Version 2 (SNMPv2c)-The second release of SNMP, described in RFC 1902, has additions and enhancements to data types, counter size, and protocol operations. See the "Understanding How SNMPv1 and SNMPv2c Work" section on page 24-5 for more information on SNMPv2. • Version 3 (SNMPv3)-This is the most recent version of SNMP and is fully described in RFC 2571, RFC 2572, RFC 2573, RFC 2574, and RFC 2575. The SNMP functionality on the Catalyst enterprise LAN switches for SNMPv1 and SNMPv2c remain intact; however, SNMPv3 has significant enhancements to administration and security. See the "Understanding SNMPv3" section on page 24-11 for more information on SNMPv3. 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 24-3