Thanks for the comment!
I didn't mean to blaim that TCP and IP is not 'clear' ( I should have used the
word 'stern', or some other word not so commendatory as 'clear') layered. What
I really wanted to say is that I prefer the choice, because I think it is a
positive example of fuzzy-layering.
Thanks for the comment again!
----- Original Message -----
From: "vinton g. cerf" <vinton(_dot_)g(_dot_)cerf(_at_)wcom(_dot_)com>
To: "Jason Gao" <jag(_at_)kinet(_dot_)com(_dot_)cn>; "Fred Baker"
<fred(_at_)cisco(_dot_)com>
Cc: <ietf(_at_)IETF(_dot_)ORG>
Sent: Friday, September 06, 2002 12:30 PM
Subject: Re: Fuzzy-layering and its suggestion
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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