[ih] NCP to TCP/IP Transition

[Craig Partridge]

I showed up just afterwards but people already referred to a flag day.
If I remember right, the flag day was the day that NCP was turned off
and people discovered exactly how well their TCP was working (not
well).

Interestingly, some of the issues I heard about were applications.
E.g. a number of sites discovered they were having trouble getting
mail working right and found it convenient to send all their mail
to a site that seemed to have its act together, and have that site
forward.  CSNET remembered the huge mail burden its servers suffered
for some years (I wouldn't be surprised if SRI-NIC had a similar experience).

But others on this list actually lived it -- this note is simply to tickle
their memories.

Thanks!

Craig

> Hi,
> 
> is my understanding correct in that it actually took more than a year to
> do the transition from NCP to TCP/IP, starting roughly in early 1982 and
> being done with by mid-1983? This is what RFC 801 (the plan), and rfc842
> through rfc848 plus rfc876 (the progress reports) seem to indicate.
> 
> I am asking because the transition is nowadays always being referred to
> as a flag day transition (which in may understanding is defined as the
> very absence of any transition period, e.g. something like changing from
> driving on the left to driving on the right side of the road), but
> apparently this was neither the case, nor was it intended to be. There
> was simply a deadline, which, of course, was not met.
> 
> Also, I am wondering, have the application layer gateways (relays) that
> RFC 801 refers to been deployed, and if yes, to which extend, and how
> successful?
> 
> And a final question, while I'm at it: How decisive was the pressure
> from DCA in this? My impression has been that without the top-down
> pressure the whole thing may well never have happened, despite all the
> money being poured into TCP/IP implementations.
> 
> Pointers to relevant literature sources are appreciated, too. Thanks
> again for your help.
> 
> Matthias
> 
> -- 
> Matthias Bärwolff
> mbaer at csail.mit.edu
********************
Craig Partridge
Chief Scientist, BBN Technologies
E-mail: craig at aland.bbn.com or craig at bbn.com
Phone: +1 517 324 3425