this was a choice made long ago to increase by a small amount the efficiency of
the representation of the two layers. Keep in mind that IP was split off of TCP
in version 3 of the protocol. They were originally combined.
vint cerf
At 09:00 AM 9/6/2002 +0800, Jason Gao wrote:
Well, I should have cited another instance. What the TCP checksum protects
includes the pseudu-header which contains the source and the destination IP
address. Transport address in TCP (and SCTP) contains IP address. Clearly the
IP address is not stored in the transport layer header. IMHO it is not an
instance of clear layering.
Vint Cerf
SVP Architecture & Technology
WorldCom
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