From: "Prakash Mariasusai, TLS-Chennai" <[EMAIL PROTECTED]>

   An UAS, on receiving an INVITE, sends a TCP packet containing two SIP
   responses in ONE Packet. Here the first SIP Response has a PARSE error,
   while the SECOND SIP Response contains a valid SIP Response.

   Note that in the first Response, the content-length is CORRECTLY formed,
   whereas other header - Cseq is malformed (it is "Cseq: 1234 1234" ,
   instead of "Cseq: 1234 INVITE")

First, the placement of bytes into packets in TCP is a matter that is
invisible to the application layer.  TCP is logically just a stream of
bytes.  (SCTP is different -- it is a stream, but the protocol can
insert record boundaries, and when SCTP is used by SIP, those
boundaries define the SIP messages.)

If SIP can parse an incoming message to the point that it can
determine the end of the message (and thus the beginning of the next
one), it should process the message as well as it can and continue
parsing with the next message.  If it has good reason, looking at an
alleged message, to think that it has lost track of the message
boundaries, it should reset the TCP connection (which forces the
sender to open a new TCP connection, with the framing re-established).

Dale
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