Transition Networks
S4224 Web User Guide
33558 Rev. C
Page 66 of 669
SNMP Configuration
Configure SNMP on this page from the
Configuration
>
Security
>
Switch
>
SNMP
>
System
menu
path.
Here you can configure S4224 SNMP System, Communities, Users, Groups, Views, Access and trap
parameters. Simple Network Management Protocol (SNMP) is part of the TCP/IP protocol for network
management. SNMP allows diverse network objects to participate in a network management architecture.
It enables network management systems to learn network problems by receiving traps or change notices
from network devices running SNMP.
The SNMP agent embedded in the S4224 is capable of version 1, 2c, or v3 support to access all
management information from the device. The community strings for v1 and v2c and the USM/VACM for
SNMPv3 are supported. The SNMP agent can support IPv4 and IPv6 trap destinations. It also supports
the INFORM PDU for notification along with traps.
Traps are generated when a condition has been met on the SNMP agent. These conditions are defined in
the Management Information Base (MIB). The administrator then defines thresholds, or limits to the
conditions, that are to generate a trap. Conditions range from preset thresholds to a restart.
All of the values that SNMP reports are dynamic. The information needed to get the specified values that
SNMP reports is stored in the MIB. This information includes Object IDs (OIDs), Protocol Data Units
(PDUs), etc. The MIBs must be located at both the agent and the manager to work effectively.
SNMP v1, v2c, v3 Descriptions
Each SNMP version is described below.
SNMPv1
SNMP version 1 (SNMPv1) is the initial implementation of the SNMP protocol. SNMPv1 operates over
protocols such as User Datagram Protocol (UDP), Internet Protocol (IP), OSI Connectionless Network
Service (CLNS), AppleTalk Datagram-Delivery Protocol (DDP), and Novell Internet Packet Exchange
(IPX). SNMPv1 is widely used and is the de facto network-management protocol in the Internet
community. The first RFCs for SNMP, now known as SNMPv1, appeared in 1988: RFC 1065, RFC 1066,
and RFC 1067. These protocols were obsoleted by SNMPv1: RFC 1155, RFC 1156 and RFC 1157. After
a short time, RFC 1156 (MIB-1) was replaced by the more often used
RFC 1213 - Version 2 of
management information base (MIB-2) for network management of TCP/IP-based internets
. SNMPv1 was
criticized for its poor security. Authentication of clients is performed only by a "community string", in effect
a type of password, which is transmitted in cleartext.
SNMPv2 and v2c
SNMPv2 (RFC 1441–RFC 1452) revises SNMPv1 and includes improvements in the areas of
performance, security, confidentiality, and manager-to-manager communications. It introduced
GetBulkRequest, an alternative to iterative GetNextRequests for retrieving large amounts of management
data in a single request. However, the new party-based security system in SNMPv2, viewed by many as
overly complex, was not widely accepted.
Community-Based Simple Network Management Protocol version 2, or SNMPv2c, is defined in RFC
1901–RFC 1908. In its initial stages, this was also informally known as SNMPv1.5. SNMPv2c comprises
SNMPv2 without the controversial new SNMP v2 security model, using instead the simple community-
based security scheme of SNMPv1. While officially only a "Draft Standard", this is widely considered the
de facto SNMPv2 standard.
User-Based Simple Network Management Protocol version 2, or SNMPv2u, is defined in RFC 1909–RFC
1910. This is a compromise that attempts to offer greater security than SNMPv1, but without incurring the
high complexity of SNMPv2. A variant of this was commercialized as SNMP v2*, and the mechanism was
eventually adopted as one of two security frameworks in SNMP v3.
