[HECnet] Multinet Tunnel Connections to SG1::

[Johnny Billquist]

On 2012-06-06 22:40, Rob Jarratt wrote:

No, you have not misunderstood. You are just not getting the full picture.
Yes, the Cisco box will transport the DECnet frames inside something. At
the
bottom there will be IP, but most likely the DECnet frames are actually
sitting
inside UDP...

So what is the difference from the bridge program, you ask.
Well, simple, the bridge program tries to be clever about which frames to
send where, but it cannot be clever enough at times, and also there are
times when it is forced to send traffic that we might want to limit.
The reason is that the bridge is not really a part of the DECnet traffic,
but is
just relaying packets back and forth, making the two ends of the bridge
appear as if they were on the same ethernet segment.
The Cisco box, on the other hand, is a DECnet routing node. It sits on the
ethernet, and participate fully in the DECnet traffic.


Thanks. Now I get it. I didn't know that anyone other than DEC ever made
something that could route actual DECnet and therefore did not realise that
"actual DECnet router" meant "actual DECnet router" :-) Until now I thought
this was something only available in a VMS router node.

VMS not required... MIM is an area router running RSX. :-)
But yeah, "DECnet router" really meant just that.

It would be a fun exercise to turn the bridge into an actual DECnet router.
One day, when I have a lot of time I might even think about trying that.

Feel free. The specifications are out there, so it's definitely not an impossible task. But I guess it will take some work. It would be very nice if the bridge did turn into a WAN router...

	Johnny