[Simh] [HECnet] TOPS-20 V4.1 DECnet

[Phil Budne]

> From: <simh at swabhawat.com>
> Date: Fri, 2 May 2014 20:02:12 +0200
....
> Tim Litt mentioned a while ago that Tops20 4.1 was rather more of a phase-II
> then a III; I call it phase-II+ as it appears to have some routing
> functionality.

I started at DEC around October of 1981, and at that time Phase II was
the rule, and everything supported "poor man's routing"; You specified
HOP1::HOP2::HOP3..... and the intermediate hops were made by
connecting to a "pass thruough" listener on an adjacent node.  TOPS-20
5.1 with Phase III made it onto the layered products machine (KL2137)
not long after I arrived.

My recall is that the KL was never a router until Phase IV. A DN20 was
loaded with software ISTR everyone loved to hate (MCB?) that did Phase
III routing, so the KL may have been just a Phase II-ish endnode that
knew about Phase III addressing, and I wouldn't expect much more of
the KS, so multiple DECnet circuits on a KS may just not make much
sense.

But I was just a lowly FORTRAN team member....

Phil