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This is the default behavior of FreeSWITCH, although most of the example configs turn on late negotiation in their profiles.
General principle
- When leg A calls FreeSWITCH, the offered codecs will be compared against the content of inbound-codec-prefs in the relevant SIP profile. As soon as a codec offered by A matches a codec allowed by FS, it is selected as the codec for leg A. If none of the offered codecs matches the allowed codecs, the call fails.
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