Nortel SMC 2450, Руководство по внедрению

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Secure UNIStim deployment Page 123 of 260
Secure Multimedia Controller Implementation Guide
Security policy
By default, the SMC defines a security policy for all clients. This is not visible
in the Secure UNIStim configuration wizard but you can change or enhance
the security policy the
Multimedia Security > UNIStim Security > Client
> Policy page in the Web UI.
Each policy is tied to a subnet or a set of subnets upon which the clients
reside. You can specify a single client with a 32-bit mask. You can associate
different policies to individual client groups.
Configuration options for security policies:
• Upgrade to secure session: Tries to convert an insecure session to a
secure session.
• Require client security: Allows only secure sessions and denies all
insecure sessions.
• Enable session caching: Provides a quicker handshake if the phone
restarts. Nortel recommends session caching.
• Key renewal: Specifies renewal intervals for the different keys used in
the handshake.
• Firmware check: Enables the SMC to consult the IP Client Firmware
table to confirm that the IP phones support UNIStim security for new
connections. Nortel recommends firmware checking if you have a
heterogeneous mix of IP phones, including IP phones that do not support
security.
• Automatic fingerprint update: Updates the fingerprint on clients that
were never configured for security. Automatic fingerprint updating runs
when the SMC is first inserted into a network so that you do not need to
manually configure the IP clients.
• Security in External Redirections: Maintains the current security level in
redirections to external servers,.