[ih] TCP 2.5

[Bob Braden]

The way I recall it, we had a meeting (maybe at ISI?) at which it was
decided to split TCP from IP.  We implementors went home with the
task of implementing that split in our code base, an interesting
exercise as I recall... no other changes in the header format but
the split.  We called that 2.5.  Meanwhile the protocol gurus were going to
write up a new version, with some mods to the header formats, which
became version 3.

I would sure like someone else from that time to verify my memory
on this.

Bob Braden