Re: TI-H: Radio switch

To: <ti-hardware@lists.ticalc.org>
Subject: Re: TI-H: Radio switch
From: "David Knaack" <dknaack@geocities.com>
Date: Sat, 9 Jan 1999 12:11:03 -0600
Delivered-To: ti-hardware-outgoing@towerguard.unix.edu.sollentuna.se
Reply-To: ti-hardware@lists.ticalc.org


From: Jeff Dezur <jeffd@wwnet.net>
>Also, did I hear this right? The cable modems are sort of like the old
token
>ring networks, where if one person on the network is essentially hogging
>bandwidth, it slows down everyone else?

You'll see that on most networks.  Take thinnet for example, only one
computer can be transmitting at a time, if one or two are running at
their peak speed they can slow down access for everyone (of course
at 10Mbit or more it takes more than a couple users on typical PCs
to make much of a dent in the bandwidth).

Things are a bit better on 10BaseT, where each computer has a connection
directly to a hub.  Some hubs (switchs actually) will send the packets only
to the computer that is supposed to be receiving them, that means that
those packets aren't slowing down other connections (as long as you're
within the total throughput for the switch).

>I know that the ADSL lines that
>the phone company I'm with is putting in, it eliminates this "bandwidth
>sharing" problem (if you want to call it a problem).

Cable modems are kind of like thinnet (apparently), everbody shares
the available bandwidth on the hardware.  ADSL is more like 10BaseT
on a good switch, you get the full bandwidth to the switch, but the switch
can only handle a fraction of the sum of the bandwidth of the incomming
lines, if everybody wants to max out their connections you will still see
some slowdowns.

All networks share the available bandwidth, its just a matter of where
exactly the limitation is.  The combination of hardware, location of the
speed bottlenecks and usage charactaristics will determine which type
of connection is faster in a given location.

> I also noticed that our
>ADSL lines are supporting 10mbits both ways (up & down). Kinda cool,

The cable modem service here has a mode like that, about the same
speed I think.

Phone service in this area is still testing ADSL, at least they've finally
got SOME kind of high bandwidth service!

One of the problems I've seen with cable modems is that some
providers don't have any kind of service monitering.  If your connection
goes down they don't know about it.  The determine which areas need
service by the number of tech support calls they get from each area!

DK

Follow-Ups:

Re: TI-H: Radio switch

From: Grant Stockly <gussie@alaska.net>