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Configuring the Cisco VGD 1T3 Voice Gateway as an H.323 or SIP Gateway
Configuring SIP Gateways
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Cisco VGD 1T3 Voice Gateway Software Configuration Guide
Verifying the H.323 Voice Gateway Interface
To verify the H.323 voice gateway interface, enter the show gateway command to verify gateway
configuration by displaying the current registration information and gateway status.
For more information about the procedures for configuration of an H.323 gateway router, refer to the
Cisco IOS H.323 Configuration Guide
.
Configuring SIP Gateways
This section provides basic configuration information for SIP gateways:
•
Prerequisites for Basic SIP Configuration, page 130
•
Information About Basic SIP Configuration, page 130
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Performing a Basic SIP Configuration, page 132
•
Configuration Examples for Basic SIP Configuration, page 145
•
Additional Information, page 153
Prerequisites for Basic SIP Configuration
•
Ensure that your SIP gateway supports 300 or 302 Redirect messages.
Information About Basic SIP Configuration
To perform basic SIP configuration tasks, you should understand the following concepts:
•
SIP Register Support—With H.323, Cisco IOS gateways can register E.164 numbers of a POTS dial
peer with a gatekeeper, which informs the gatekeeper of a user’s contact information. SIP gateways
allow the same functionality, but with the registration taking place with a SIP proxy or registrar. SIP
gateways allow registration of E.164 numbers to a SIP proxy or registrar on behalf of analog
telephone voice ports (FXS), IP phone virtual voice ports (EFXS), and local SCCP phones.
•
SIP Redirect Processing Enhancement—SIP Redirect Processing allows flexibility in the handling
of incoming redirect or 3xx class of responses. Redirect responses can be enabled or disabled
through the command-line interface, providing a benefit to service providers who deploy Cisco SIP
gateways. Redirect processing is active by default, which means that SIP gateways handle incoming
3xx messages in compliance with RFC 2543. RFC 2543 states that redirect response messages are
used by SIP user agents to initiate a new Invite when a user agent learns that a user has moved from
a previously known location.
•
SIP 300 Multiple Choice Messages—If multiple routes to a destination exist for a redirected number
(multiple dial peers are matched), the SIP gateway sends a 300 Multiple Choice message, and the
multiple routes in the Contact header are listed. The redirect contact order command gives you the
flexibility to choose the order in which routes appear in the Contact header.