Cisco NCS 5000 Series, Руководство пользователя

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• set-request — Operation that stores a value in a specific variable.
•
trap
—
Unsolicited message sent by an SNMP agent to an SNMP manager when some event has occurred.
Table 1 identifies other key SNMP features supported by the SNMP v1, v2c, and v3.
Table 2: SNMPv1, v2c, and v3 Feature Support
SNMP v3 SNMP v2c SNMP v1 Feature
Yes Yes No Get-Bulk Operation
Yes (No on the
Cisco IOS XR software) Yes (No on the
Cisco IOS XR software) No Inform Operation
Yes Yes No 64 Bit Counter
Yes Yes No Textual Conventions
Yes No No Authentication
Yes No No Privacy (Encryption)
Yes No No Authorization and Access
Controls (Views)
Security Models and Levels for SNMPv1, v2, v3
The security level determines if an SNMP message needs to be protected from disclosure and if the message
needs to be authenticated. The various security levels that exist within a security model are as follows:
•
noAuthNoPriv
—
Security level that does not provide authentication or encryption.
•
authNoPriv
—
Security level that provides authentication but does not provide encryption.
• authPriv — Security level that provides both authentication and encryption.
Three security models are available: SNMPv1, SNMPv2c, and SNMPv3. The security model combined with
the security level determine the security mechanism applied when the SNMP message is processed.
Table 1 identifies what the combinations of security models and levels mean.
Table 3: SNMP Security Models and Levels
What Happens Encryption Authentication Level Model
Uses a community
string match for
authentication. No Community string noAuthNoPriv v1
System Management Configuration Guide for Cisco NCS 5000 Series Routers, IOS XR Release 6.2.x
22
Implementing SNMP
SNMP Versions