Lecture 23: Network Management #3

The SNMP Protocol

SNMP version 1 only defines four operations:

get: retrieve specific management information from a managed node^[2]
get-next: retrieve via MIB traversal, management information. See later.
set: used to manipulate management information.
trap: used to report extraordinary events.

It also defines the reply operation:

get-response: contains the information requested from the managed node.

An SNMP message contains, along with data describing the SNMP commands or responses, a community name identifying that the sender is a member of an identified community, or group of managed nodes. This allows a trivial level of authentication, since the community name almost always defaults to "public".

^[2] The SNMP get request, despite having a superficially similar name to the HTTP GET request, is utterly and completely unrelated to it. SNMP requests and responses are ASN.1 objects, encoded using BER, see below. They have no similarity to the HTTP "plain text" protocol.

Lecture 23: Network Management #3

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