request for info
- To: mail-tcp-group
- Subject: request for info
- From: brian@ucsd.Edu (Brian Kantor)
- Date: 23 Feb 91 01:29:01 GMT
Since we are, for the forseeable future at least, stuck with AX.25, I
believe the proper way to handle ham networking is to have a router
that works at the AX.25 level, routing ALL the embedded protocols
(net/wrong, IP, etc).
There are essentially three key items to making a network such as this
work satisfactorily and dependably:
1. RF hardware
2. Networking hardware
3. Networking software
At this moment, most people can handle #1 once they get the sites,
and #2 has been or is being solved as we speak. #3 is what we don't
#1 just takes good quality radios. I tend to use Motorola and GE stuff
because it's built like a battleship and is real cheap on the used
My first cut at #2 is being done by hacking heavily on a PC with DRSI
and PI cards; later it will go on some standalone dedicated hardware
such as the Grace card, PS-186, or the Kantronics Data Engine.
My solution to #3 is probably going to grow out of NOS, since I don't
have source for anything else. NOS is immense compared to what I need,
but I can probably rip most of the baggage out and make it a lean
packet switch. Right now, NOS is clearly an end-user widget, not a
networking switch. A switch is what I need.
Given that I manage to get the time and people to help, the plan is for
each community to have one or more highspeed links that connects sites
around the area to other areas - a trunk, if you will. For most areas
of the country, that is probably 9600 or 19200 bps, although in the San
Diego to Los Angeles corridor we're planning on 56kb as soon as we can
get the necessary sites lined up.
In addition to the trunk channel, there will be 1200 bps and 9600 bps
user access. Currently I'm doing that with 1200 bps simplex (i.e.,
traditional packet style) and a 9600 bps realtime repeater, both on two
meters, where I think user access channels should be.
The switch will have to intelligently route all popular AX.25-imbedded
protocols, which is no easy task. Ah well, in my copious free time.
In the meantime, we're using G8BPQ software since it's much more
convenient (and cheaper!) than buying net/rom chips. It not only acts
as a net/rom router, but also serves as a front end to NOS, so we get
IP routing in the package.
That's all on the ground right now, under development. The existing
network is net/rom with 1200 bps user access on 2m and 4800 bps
intercity trunks on 6m. Works real well, but only for vanilla AX.25 and
I'm surprised more people don't use 6m for packet; it's practically an
empty band, and FM (FSK) radios usually don't bother TVs. Not only
that, but your ham site neighbors don't mind it, since they're usually
not using 6m either. Sure has nice long-haul characteristics.