[Info-vax] terminal servers etc

[Peter 'EPLAN' LANGSTOeGER]

In article <6a9348c5-8325-4041-bcb9-a1dc90b8b520 at googlegroups.com>, Bart Zorn <bart.zorn at gmail.com> writes:
>The DEChub 90 itself has only a 10baseT connection.

Typo!! It only has a 10Base2 connection (aka Thinwire, RG-50 or cheapernet).
It is in the DEChub90 backplane, with one end terminated and the other end
on a connector on the right side of the DEChub90

You could plug in any DEChub90 series modules, but those requiring 12V (for
AUI - like in the DECbridge90) only in the most right slot (8 and maybe 7).

The 90 modules all had the thinwire interface connected to the connector
for the DEChub90 on the rear and to the real BNC connector on the side of
the module. Means you could use both, but not on the same time (that is why
the connector is on the side of the module, which is unaccessable in a hub).

Some later modules like the DECserver90M had UTP (on the front) in addition
to BNC (on the side) but limitation was still there (backplane or UTP or BNC)

btw: Don't confuse this with the DECrepeater90 modules which had BNC, or UTP
or fibre ifcs (on the front) *in addition* (to BNC on the side and backplane).

There also was a stack module for the 90 series, which used the rear connector
of the 90 modules only for the agent functions (DECagent90) by having a tiny
cable between the stack modules - forming a ring of the stack modules - but
using the side BNCs for the net of the stack (50Ohm cable with T-connectors).

>But all plugged in devices are connected to that same segment: it is a hub.
>You should put a 50 Ohm terminator on the BNC of the DEChub if you do not
>connect a coax cable.

Correct

-- 
Peter "EPLAN" LANGSTÖGER
Network and OpenVMS system specialist
E-mail  Peter at LANGSTOeGER.at
A-1030 VIENNA  AUSTRIA              I'm not a pessimist, I'm a realist