Avaya P334T-ML 사용자 설명서

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Chapter 8        User Authentication
Avaya P334T-ML User’s Guide
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’WriteCommG’ group by default. This allows you to
 view the agent’s MIB tree and 
change any of the values in the MIB tree.
L If you delete the ReadCommN or WriteCommN users, the ReadCommG or 
WriteCommG groups, or the SNMPv1View you may not be able to access the 
switch using SNMPv1 or SNMPv2c.
In addition, traps are sent to designated trap receivers. Packets with trap 
information also contains a trap community string.
SNMPv2c
SNMPv2c is very similar to SNMPv1. However, SNMPv2c adds support for the 
get-bulk action and supports a different trap format.
SNMPv3
SNMPv3 enables the following features over SNMPv1 or v2c:
User authentication with a username and password.
Communication encryption between the Network Management Station (NMS) 
and the SNMP agent at the application level
Access control definition for specific MIB items available on the SNMP agent
Notification of specified network events directed toward specified users
Definition of roles using access control, each with unique access permissions 
and authentication/encryption requirements
The basic components in SNMPv3 access control are users, groups, and views. 
In addition. SNMPv3 uses an SNMP engine ID to identify SNMP identity. An 
SNMP engine ID is assigned to each IP address of each device in the network. Each 
SNMP engine ID should be unique in the network.
Users
SNMPv3 uses the User-based Security Model (USM) for security, and the 
View-based Access Control Model (VACM) for access control. USM uses the 
HMAC-MD5-96 and HMAC-SHA-96 protocols for user authentication, and the 
CBC-DES56 protocol for encryption or privacy.
A maximum of 21 users, including local users and remote users getting notifications 
can be defined on a stack. If the SNMP engine ID changes, all users other than the 
default user for the stack are invalid and must be redefined. The SNMP engine ID 
can be changed via the CLI. In addition, a change in the IP address of the stack 
automatically changes the SNMP engine ID.
SNMPv3 supports three security levels:
NoAuthNoPriv
 – This is the lowest level of SNMPv3 security. No (Message 
Authentication Code) MAC is provided with the message, and no encryption is 
performed. This method is maintains the same security level as SNMPv1, but 
provides a method for limiting the access rights of a user.