Archived from groups: alt.internet.wireless (
More info?)
On Wed, 04 Aug 2004 21:39:45 GMT,
info_at_cabling-design_dot_com@foo.com (Dmitri(Cabling-Design.com))
wrote:
>I guess, that would mean that Jeff crimped RJ45 plugs on the wire and run
>10BASE-T between the APs.
Correct.
The owner did not want to pay me to do a proper wiring job. To run
the CAT5, he will probably bribe his 15 year old son, who in turn will
borrow all the wire, tools, connectors, etc from me to do the job.
In about a week, I expect to be invited to dinner where I'll be asked
to fix the crimping job. Incidentally, he had several perfectly good
RG-6/u coax runs available, which I wanted to use with media
converters (or old hubs) for 10base2, but the owner didn't want to pay
me for the hardware.
Beware of doing business with cheap friends.
>I would also guess that, even with high bit
>error rates the wired link was probably still faster than the "b"
>wireless.
Not really. There's a big problem with NWAY negotiation when using
cheap routers, access points, and switches. Few offer any control
over the negotiated speed and protocol (half vs full duplex). The
result is that the two access points could easily settle on
100baseTX-FDX and end up just sending errors back and forth over the
poor quality cabling. While 10baseT-HDX would work just fine, there's
no configurable way to force 10baseT on most cheap access points.
What I have to do is insert an old 10baseT hub (not switch) in the
line so that each router/AP see's only the hub. Then NWAY switches to
10baseT-HDX. In this specific case, the ancient Eumitcom access point
did only 10baseT-HDX on the LAN port, so there was no problem. This
is one case where faster (ethernet) is not better.
As for performance, 10baseT-HDX will deliver about 6Mbits/sec which is
approximately the same as what an 11Mbit/sec 802.11b connection will
deliver under ideal conditions. It's a good match for an 802.11b
access point. However, if he had used an 802.11b repeater, the
thruput would have been cut in half because the RF link is half duplex
and everything needs to be sent twice. I also doubt that I could
maintain an 11Mbits/sec wireless association through multiple walls in
a building. Of course 100baseT would be better, but not with junk
telco station wire.
>The best (though time consuming) way to borrow that cable would be to use
>it as a pull string for a brand new CAT5E (CAT6) cable, which would
>provide enough throughput to link two "g" APs.
Yep. 802.11g delivers about 33Mbits/sec thruput. No way is 10baseT
going to handle that.
--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558