RFC 3486:Compressing the Session Initiation Protoc...
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... Therefore, the presence of comp=sigcomp indicates that the SIP entity identified by the URI or by the Via header field ...


... A SIP entity receiving a compressed message has to decompress it and to parse it. This requires slightly more processing power ...
... sigcomp in a SIP message could make a SIP entity send compressed messages to another SIP entity that did not support SigComp. Appropriate integrity mechanisms ...
... SIP message could make a SIP entity send compressed messages to another SIP entity that did not support SigComp. Appropriate integrity mechanisms should be used to avoid this attack ...



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