SIP and ISDN use different response messages to communicate why a call failed or could not be connected (Q.850 for ISDN and SIP Responses for SIP). By default, the Sonus SBC 1000/2000 system the
uses
RFC 4497 to map these to each other. Override Tables allow you to override one or more of these mappings to a different message, which is useful for interoperating with nonstandard equipment. To use a table created here, select it from the SIP to Q.850 Override Tables field in a
SIP Signaling Groups entry.
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