Network Critical SmartNA-X User Manual page 64

U SNMP | A SNMP
SING BOUT AND
processing SNMP retrieval or modification request messages from a manger, and also when a notification message
must be sent to the manager. VACM elaborates on the community string concept by allowing a much stricter and
more dynamic access control model that is easy to administer.
Model
v1
v2c
v3
v3
v3
Table 9-1 SNMP Security Models and Levels
Agent functions
The SNMP agent responds to SNMP manager requests as follows:
• Get a MIB variable—The SNMP agent begins this function in response to a request from the NMS. The agent
retrieves the value of the requested MIB variable and responds to the NMS with that value.
• Set a MIB variable—The SNMP agent begins this function in response to a message from the NMS. The
SNMP agent changes the value of the MIB variable to the value requested by the NMS.
The SNMP agent also sends unsolicited notification messages to notify an NMS that a significant event has
occurred on the agent. Examples of notification conditions include, but are not limited to, when a port or module
goes up or down, when spanning-tree topology changes occur, and when authentication failures occur.
S NA-X
MART
Level
noAuth
noAuth
noAuth
auth
priv
S NA™ 10G N
MART
Authentication Encryption
Community secret No
Community secret No
Username No
MD5 or SHA No
MD5 or SHA DES, AES
DRAFT
A (S NA-X)
ETWORK CCESS MART
What happens
Uses a community secret
match for authentication.
Uses a community secret
match for authentication.
Uses a community secret
match for authentication.
Provides authentication
based on the MD5 or
SHA algorithms.
Provides authentication
based on the MD5 or
SHA algorithms.
Provides DES and AES
encryption in addition to
authentication.
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