On Thu, 19 Jul 2001, Corey Gilmore wrote:
> Anyone know what the current problem is with our service? UVM is
> unreachable from off campus - is this another provider problem?
Hi Corey and other folks.
Just a couple of comments which might help in diagnosing
issues like this in the future.
1. UVM does not have "an" internet connection
UVM has at least THREE interenet connections.
Connection 1 is via Verison - 10 Mbps (ethernet speed)
(Mbps = megabits per second)
Connection 2 is vial Hyperion - also at 10 Mpbs
Connection 3 is via Internet2 - nominally at 45
Mbps, effectively at 25 Mbps. This circuit,
however, is mainly for "inter-university"
traffic. You can't reach Disney.Com via this
route, for example.
2. "Off Campus" has even more internet service connections
Earthlink (nee Together.net) has a "short cut"
to UVM for Together.Net dial up customers who
subscribed to the old together.net service.
There are occassional glitches here, and this
service is, I believe, being phased out.
Sover.Net. Check for news about this elsewhere.
All other internets. Here, is where things
really get interesting ! Most other networks
really uses "internet" technology to the
fullest. No short cuts. In fact, sometimes
the route from A to Z(oo) may have 4 or 5 different
ways to be accomplished. It's the job of the
internet "routers" (small computers grown in a
very small town in France, pronounced "Routier")
to figure out how to get from A to B using
Pascal's Triangles (1)). Sometimes the triangles
3. The network is always changing.
At any particular moment of time, some part of
the network is always not working. It's the job
of the routers to relearn the network as
needed AND to report problems to some
human who might be needed to fix some
broken part. Sometimes this takes a while.
The BEST advice is to give the network 6 minutes
to heal itself. The routers generally can
rebuild the network on their own and work around
a broken part.
The next best advice is to give the network 36
minutes to heal itself. (Actually the 36
minutes usually are needed for the humans to
figure out what the computers couldn't figure
out on their own - often this requires replacing
a circuit board or replacing a backhoe severed
4. Know thy network.
If you are interested in figuring out where
the breakage was, one thing you'll want to do is
find out out where the starting point was and
where the ending point is. And then, using tools
like "nslookup", try to figure out what parts
of the network might be in between ...
As difficult as this might seem, it's a really
good lesson in computing and information
technology. It makes the wonders of the network
all that more amazing - that you can be
anywhere in the world and read your email -
without knowning anything about phone cards,
international dialing codes, etc. Truly mind