32-3
Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter32 Configuring SNMP
Understanding SNMP
Table32-1 identifies the characteristics of the different combinations of security models and levels.
You must configure the SNMP agent to use the SNMP version supported by the management station.
Because an agent can communicate with multiple managers, you can configure the software to support
communications using SNMPv1, SNMPv2C, or SNMPv3.
Table32-1 SNMP Security Models and Levels
Model Level Authentication Encryption Result
SNMPv1 noAuthNoPriv Community string No Uses a community string match for authentication.
SNMPv2C noAuthNoPriv Community string No Uses a community string match for authentication.
SNMPv3 noAuthNoPriv Username No Uses a username match for authentication.
SNMPv3 authNoPriv Message Digest 5
(MD5) or Secure
Hash Algorithm
(SHA)
No Provides authentication based on the HMAC-MD5 or
HMAC-SHA algorithms.
SNMPv3 authPriv
(requires the
cryptographic
software image)
MD5 or SHA Data Encryption
Standard (DES)
or Advanced
Encryption
Standard (AES)
Provides authentication based on the HMAC-MD5 or
HMAC-SHA algorithms. Allows specifying the
User-based Security Model (USM) with these
encryption algorithms:
DES 56-bit encryption in addition to
authentication based on the CBC-DES (DES-56)
standard.
3DES 168-bit encryption
AES 128-bit, 192-bit, or 256-bit encryption