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Re: Cable Modems (fwd)
David Lesher wrote:
>From what I have read, I think the Motorola Cablecomm
equipment has the best chance of success. TCI has commited to buy
200,000
of them I think.
http://www.mot.com/MIMS/Multimedia/
>
> {fwd}
> From: Lars Poulsen <lars@silcom.com>
>
> This is an attempt to start a fresh discussion about cable modem technology.
> I am submitting this both to the TELECOM DIGEST (telecom@massis.lcs.mit.edu)
> and COM-PRIV@lists.psi.com, as well as to a couple of people I have discussed
> related issues with in the past.
>
> Many of us believe that the best bet to give the local telephone companies
> competition is the CATV operators. When it looked like such a competitive
> battle was coming up, the "Baby Bells" (the local telephone companies in the
> USA) started buying into cable TV companies in the UK (United Kingdom of
> England, Scotland Wales and Northern Ireland) in order to understand the game
> from the other side. They seemed to be quite successful.
>
> Now, in the US, we are seeing the telephone companies pushing to be alllowed to
> become ISPs (Internet Service Providers) through unregulated subsidiaries.
> And the Cable companies are trying to start pilot projects with Internet
> access.
>
> I asked an Australian, who said OPTUS (the "dominant" telco in Australia, which
> is also the "dominant" CATV operator) is rolling out cable modems for INternet
> access:
>
> > >Which system have they settled on in your part of the world ?
> > >What is the upstream bitrate ?
>
> >** from John Wiltshire <jw@qits.net.au> 08/27/96 4:24pm +1000
> > Check out www.optus.net. They have most of the information I
> > am using there.
>
> That turned out to be a singularly uninformative piece of propaganda. Here are
> some quotes:
> "It isn't here yet - but it is coming."
> "Cable modems tend to be implemented using one of the following technologies".
>
> The company I work for has decided that it is strategically important for us to
> build a cable modem. We are hiring staff to work on it. But after we have
> started to talk to cable system operators and cable equipment builders (hybrid
> fiber-to-coax gateways) I have concluded the following about cable modems:
>
> 1. There are a few technically successful demonstrations. Some of these are
> quite successful, running a virtual ethernet over two separate cable
> channels (one out, one upstream).
> 2. The ones that are technically impressive (as described above) tend to use
> ether-to-coax boxes that cost USD 3000-USD 5000 apiece. Service at this
> price is not commercially viable.
> 3. Systems that have achieved significantly useful uplink bandwidth, have
> generally had to rebuild much of the low-level infrastructure to make it
> work. It would have been cheaper to run a new pair of telephone wires to
> the homes. (But then the telephone company would be more likely to win the
> game than the cable company. In OZ, they are the same, in the US, the game
> is perceived to be a horserace between the telco and the cable company.)
> 4. When the cable companies in the UK (which were owned by the US local
> telephone companies) rolled out telephone service to compete with British
> Telecom (in what was seen a a preview of the coming US battle between the
> telcos and the cablecos) they actually ran a telephone pair to each
> household. They designed a TV coax cable with a telephone pair attached
> on the outside, and this was used in all new TV cable installation. Thus,
> they had the telephone pair pre-positioned when they rolled out telephone
> service. It is obvious, that the apparent success of this "telephone service
> by cable companies" demonstration does not demonstrate anything of relevance
> to the US market.
> 5. There are about 15 incompatible modulation schemes, most of which can
> provide 10-30 Mbps "downstream", but most of which provide only a shared
> upstream capacity of around 2Mbps. Some systems derive NO upstream bandwidth
> from the cable, but use a telephone call (V.34) for the upstream path.
>
> Clearly, there is a significant mismatch between the hype and the reality.
>
> In such an environment, it is generally useful to have a discussion to check
> the facts. Gentle readers, have are been misled, or are the facts really that
> different from the hype and the market expectations ?
>
> / Lars Poulsen - lars@silcom.com - http://www.silcom.com/~lars/
>
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