Enterasys Networks D-Series - Manual (Page 182)

SNMP Configuration Summary
7-2 SNMP Configuration
• SNMP network management applications, such as the Enterasys NetSight application, which
communicate with agents to get statistics and alerts from the managed devices.
SNMPv3
SNMPv3 is an interoperable standards‐based protocol that provides secure access to devices by
authenticating and encrypting frames over the network. The advanced security features provided
in SNMPv3 are as follows:
– Message integrity — Collects data securely without being tampered with or corrupted.
– Authentication — Determines the message is from a valid source.
– Encryption — Scrambles the contents of a frame to prevent it from being seen by an
unauthorized source.
Unlike SNMPv1 and SNMPv2c, in SNMPv3, the concept of SNMP agents and SNMP managers no
longer apply. These concepts have been combined into an SNMP entity. An SNMP entity consists
of an SNMP engine and SNMP applications. An SNMP engine consists of the following four
components:
• Dispatcher — This component sends and receives messages.
• Message processing subsystem — This component accepts outgoing PDUs from the
dispatcher and prepares them for transmission by wrapping them in a message header and
returning them to the dispatcher. The message processing subsystem also accepts incoming
messages from the dispatcher, processes each message header, and returns the enclosed PDU
to the dispatcher.
• Security subsystem — This component authenticates and encrypts messages.
• Access control subsystem — This component determines which users and which operations
are allowed access to managed objects.
About SNMP Security Models and Levels
An SNMP security model is an authentication strategy that is set up for a user and the group in
which the user resides. A security level is the permitted level of security within a security model.
The three levels of SNMP security are: No authentication required (NoAuthNoPriv);
authentication required (AuthNoPriv); and privacy (authPriv). A combination of a security model
and a security level determines which security mechanism is employed when handling an SNMP
frame.
Table 7‐12 identifies the levels of SNMP security available on D‐Series devices and
authentication required within each model.
Table 7-12 SNMP Security Levels
Model Security Level Authentication Encryption How It Works
v1 NoAuthNoPriv Community string None Uses a community string match for
authentication.
v2c NoAuthNoPriv Community string None Uses a community string match for
authentication.