Limiting Sbc Call Duration; Sbc Authentication; Sip Authentication Server Functionality - AudioCodes Mediant 4000 SBC User Manual

CHAPTER 22 SBC Overview
The voice-related coder configuration (Allowed and Extension coders) is independent of
the fax-related coder configuration, with the exception of the G.711 coder. If the G.711
coder is restricted by the Allowed Audio Coders Groups table, it is not used for fax
processing even if it is listed in the Coder Groups table for faxes. However, support for
G.711 coders for voice is not dependent upon which fax coders are listed in the Coder
Groups table.

Limiting SBC Call Duration

You can configure the maximum allowed call duration (in minutes) per SBC call. If an established
call reaches this user-defined limit, the device terminates the call. The feature ensures that calls
are properly terminated, allowing available resources for new calls. The following procedure
describes how to configure the feature for all calls (globally). To configure the feature per specific
calls, use IP Profiles (IpProfile_SBCMaxCallDuration).
➢
To configure maximum call duration:
1. Open the SBC General Settings page (Setup menu > Signaling & Media tab > SBC folder >
SBC General Settings).
2. In the 'Max Call Duration' field (SBCMaxCallDuration), enter the maximum call duration per
SBC call:
3. Click Apply.

SBC Authentication

The device can authenticate SIP servers and SBC users (clients). The different authentication
methods are described in the subsequent subsections.

SIP Authentication Server Functionality

The device can function as an Authentication server for authenticating received SIP message
requests, based on HTTP authentication Digest with MD5. Alternatively, such requests can be
authenticated by an external, third-party server.
When functioning as an Authentication server, the device can authenticate the following SIP
entities:
■ SIP servers: This is applicable to Server-type IP Groups. This provides protection from rogue
SIP servers, preventing unauthorized usage of device resources and functionality. To
authenticate remote servers, the device challenges the server with a user-defined username
and password that is shared with the remote server. When the device receives an INVITE
request from the remote server, it challenges the server by replying with a SIP 401
Unauthorized response containing the WWW-Authenticate header. The remote server then re-
sends the INVITE containing an Authorization header with authentication information based on
this username-password combination to confirm its identity. The device uses the username
and password to authenticate the message prior to processing it.
■ SIP clients: These are clients belonging to a User-type IP Group. This support prevents
unauthorized usage of the device's resources by rogue SIP clients. When the device receives
an INVITE or REGISTER request from a client (e.g., SIP phone) for SIP message
authorization, the device processes the authorization as follows:
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Mediant 4000 SBC | User's Manual