RFC 3486:Compressing the Session Initiation Protoc...
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TLS


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... TCP and SCTP as transports, TLS for transport security and SigComp ...
... 3. TCP, TLS, no compression ...
... 4. TCP, TLS, SigComp ...
... 7. SCTP, TLS, no compression ...
... 8. SCTP, TLS, SigComp ...
... SIP use a different port for TLS on top of TCP than for TCP alone, although at ...


... URI is a SIPS URI, the request SHOULD be compressed before it is passed to the TLS layer. ...



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