On May 4, 2020, at 10:13 PM, Thomas DeBellis
<tommytimesharing at gmail.com> wrote:
Let me clarify this a bit. Leaving LAT aside, Tops-10 and Tops-20 implement two remote
terminal protocols for DECnet. The Digital common one is CTERM, which runs on all (or
most) platforms. Unfortunately, there are some minor problems with the current Tops-20
CTERM implementation that are annoying. For example, you can't use space as an
un-pause character, which I've been doing since about 1978. Fixing it (if possible)
means I've got to wade into the monitor and that could mean months before I come back
up for air.
I remembered a previous remote terminal protocol (NRT) that I think was available in
either late Phase II or Phase III, but only between 20's (and eventually 10's).
It is in no way as rich as CTERM (the difference perhaps being reminiscent of that between
FTP and DAP), but it is far less complex. It appears to have been modeled in some ways
along the lines of the Tops-20 ARPA NCP NVT (without the IAC negotiations). The interface
is close enough so that the Tops-20 TELNET program can use it.
However, the Tops-20 NRT CLIENT (SETHOST) appears to have been effectively abandoned in
favor of the CTERM client and this is understandable, given that CTERM was the common
platform and corporate direction. That it is unfortunate as NRT is more efficient. Most
importantly, NRT doesn't have the above annoyances. But SETHOST needed further
productization. Like FAL/DAP, bugs hurtled out of it as I started using it. MRC had
modified it to assume a 2020 (I.E., Tops-20 4.2) which denied other efficiencies. Right
now, I've got about eight fixes and enhancements in. It's quite tolerable.
CTERM isn't implemented by DECnet/E (RSTS). But it does implement the older protocol,
and for that matter it implements the pre-CTERM protocols used by RSX and by VMS. These
are in the "unsupported" version of the set-host utility (net.tsk) which is part
of the kit. The supported version only implements the RSTS remote terminal protocol. But
the other one works well, as it has to -- it was the one used throughout DEC's
internal network.
paul