[Tsvwg] Re: [e2e] e2e principle..where??....

[John Day]

At 18:41 -0400 6/4/01, Manish Karir wrote:
>so with this description a satellite system that uses 2 proxies
>on each end of a satellite link and does its own protocol between
>the proxies is also compatible with the e2e argument.
>server---proxy1---proxy2---client
>so long as the bits comming out on the proxy1---server and
>proxy2--client are the same...?
>the only gurantee is that as you say.."the bits get delivered
>as sent......and the bits are unmodified..."
>so inbetween the 2 proxies compression etc...are all completely valid?
>
>If as you say, the e2e argument does not say what happens inside the
>network, then I guess the above would hold true....

This violates the e2e argument as we have discussed.  Since it is a 
hop by hop solution, reliablility cannot be guaranteed; so neither 
can the semantics.  This is precisely the argument that started this, 
i.e. the PTT argument that X.25 did not need a transport protocol on 
top of it.  My point was that client - - - - proxy, did not violate 
it as long as the proxy was up to date.

Any time there is relaying; reliability can only be guaranteed if 
there is end2end error control on top of it.  Not everything has to 
satisfy e2e, SMTP doesn't for example.  (and once in a while things 
get lost).

Take care,
John