SIP entity
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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 ...
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In order to avoid asymmetric compression (i.e., two SIP entities
exchanging compressed requests in one direction and uncompressed
requests in the other direction) proxies ...
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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 ...