Cell Relay Archive

[jwb@capek.rdt.monash.edu.au (Jim Breen)]

myoung@calon.com writes:

>In <3kt1j8$fbd@harbinger.cc.monash.edu.au>, jwb@capek.rdt.monash.edu.au (Jim Breen) writes:
>>No-one (that I am aware of) in the ATMF or IETF is looking at the idea
>>of TCP running directly over ATM VCs, because it really violates the
>>generally accepted principles of interworking 

>What to we mean a "principle"? Is this an axiom based upon the definition
>of a VC?  Is it a physical limitation of a VC?  What is it about the
>physical nature of a VC, besides some voted upon axioms, which make
>it inappropriate to run a transport layer directly on top of it?

Nothing really to do with VCs, except that not everyone has them. The 
whole reason for have an interworking protocol, implemented on top of
heaps of physical networks (of which ATM is just one), is to enable
end-end carriage of ULPs such as TCP without it having to fuss about
the underlying physical network(s). This is what I meant by "accepted 
principles of interworking". We can do away with this, when and only when,
all the known universe is on the one communication system.

Feel free to run TCP on top of ATM, HDLC, Ethernet, etc. etc., but it will
not be able to interwork with end-systems outside your own network.
-- 
Jim Breen          [$@%8%`!&%V%j!<%s(J@$@%b%J%7%eBg3X(J]
Department of Robotics & Digital Technology. Monash University. 
Clayton VIC 3168 Australia (p) +61 3 905 3298 (f) +61 3 905 3574  
j.breen@rdt.monash.edu.au   [http://www.rdt.monash.edu.au/~jwb/]