Dell PowerConnect 5524P User Manual page 308

Privacy — Protects against disclosure of message content. Cipher Block-
•
Chaining (CBC) is used for encryption. Either authentication alone can
be enabled on an SNMP message, or both authentication and privacy can
be enabled on an SNMP message. However privacy cannot be enabled
without authentication.
• Timeliness — Protects against message delay or message redundancy. The
SNMP agent compares incoming message to the message time
information.
• Key Management — Defines key generation, updates, and use.
The switch supports SNMP notification filters, based on Object IDs (OIDs),
which are used by the system to manage switch features.
Authentication or Privacy Keys are modified in the User Security Model
(USM).
SNMPv3 can only be enabled if the Local Engine ID is enabled.
SNMP Access Rights
Access rights in SNMP are managed in the following ways:
• SNMPv1 and SNMPv2 — Communities
The community name is a password sent by the SNMP management
station to the device for authentication purposes.
A community string is transmitted along with the SNMPv1,v2 frames, but
neither the frames nor the community string are encrypted. Since
SNMPv1 and SNMPv2 are not encrypted, they are not secure.
Communities can be associated with views or groups, and they are defined
in the Community pages.
• SNMPv3 — Users and Groups
SNMP v3 works with users instead of communities. The users belong to
groups that have access rights assigned to them. Users are defined in the
User Security Model pages
SNMPv3 provides two security mechanisms:
– Authentication — The switch checks that the SNMP user is an
authorized system administrator. This is done for each and every
frame.
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Dell PowerConnect 55xx Systems User Guide