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SNMP
SNMP
Simple Network Management Protocol (SNMP) provides a method for managing network devices. The
device supports SNMP version 1, SNMP version 2, and SNMP version 3.
SNMP v1 and v2
The SNMP agent maintains a list of variables, which are used to manage the device. The variables are
defined in the Management Information Base (MIB). The MIB presents the variables controlled by the
agent. The SNMP agent defines the MIB specification format, as well as the format used to access the
information over the network. Access rights to the SNMP agent are controlled by access strings.
SNMP v3
SNMP v3 also applies access control and a new traps mechanism to SNMPv1 and SNMPv2 PDUs. In
addition, the
User Security Model (USM) is defined for SNMPv3 and includes:
Authentication:
Provides data integrity and data origin authentication.
Privacy:
Protects against disclosure of message content. Cipher-Block-Chaining
(CBC) is used
for encryption. Either authentication is enabled on an SNMP message, or both authentication and
privacy are enabled on an SNMP message. However privacy cannot be enabled without authenti-
cation.
Timeliness:
Protects against message delay or message redundancy. The SNMP agent com-
pares an incoming message to the message time information.
Key Management:
Defines key generation, key updates, and key use.
The device supports SNMP notification filters based on Object IDs (OID). OIDs are used by the system
to manage device features. SNMP v3 supports the following features:
Security
Feature Access Control
Traps
Authentication or Privacy Keys are modified in the SNMPv3 User Security Model (USM).
