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Re: [RE] What's wrong using FireWire as the home backbone?



<DC> I am attaching few backup slides left out of the CFI, for reference
to the "comparing various technologies" discussion. From the people
involved in the reflector, so far we have Ethernet and 1394 technologies
as candidates for home networking. There are others, like (wired) Power
Line, USB, (wireless) Bluetooth, HomeRF, 802.11, etc...

As far as the discussion about Ethernet vs 1394, I think that Ethernet
is more of a NETWORKING technology than 1394, although 1394 supports
synchronization. So the question becomes: is it easier to turn 1394 into
Ethernet (net tech), or vice-versa? From a pure technological
standpoint, which is the easiest task? Also, from a practical
perspective, what is the technology of choice for AV CE devices -
Ethernet interfaces or 1394?

</DC>

Dirceu Cavendish
NEC Labs America
10080 North Wolfe Road Suite SW3-350
Cupertino, CA 95014
Tel: 408-863-6041 Fax: 408-863-6099


-----Original Message-----
From: owner-stds-802-3-re@IEEE.ORG [mailto:owner-stds-802-3-re@IEEE.ORG]
On Behalf Of David V James
Sent: Thursday, September 02, 2004 12:39 PM
To: STDS-802-3-RE@listserv.ieee.org
Subject: Re: [RE] What's wrong using FireWire as the home backbone?

Kevin,

>> 1/ FireWire does not like to go further than 4.5m
Good point, for the basline PHYs. It does, however,
get a bit fuzzy on some of physical layers, possibly
allowing more.


>> 2/ FireWire does not scale well -
>> fixed amount of bandwidth is shared amongst all devices on the
network.

This is a misperception shared by all too many.

Firewire devices can extend themselves, without a bridge,
for up to 63 devices. This is similar to Ethernet hubs.

Firewire groups can go through bridges, for up to 1022 bridges.
This is similar to Ethernet bridges.


>> 3/ FireWire is not Ethernet
I agree, and this is the main point.

DVJ

David V. James
3180 South Ct
Palo Alto, CA 94306
Home: +1.650.494.0926
      +1.650.856.9801
Cell: +1.650.954.6906
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Base: dvj@alum.mit.edu

>> -----Original Message-----
>> From: owner-stds-802-3-re@IEEE.ORG
>> [mailto:owner-stds-802-3-re@IEEE.ORG]On Behalf Of Gross, Kevin
>> Sent: Thursday, September 02, 2004 11:50 AM
>> To: STDS-802-3-RE@listserv.ieee.org
>> Subject: Re: [RE] What's wrong using FireWire as the home backbone?
>>
>>
>> -----Original Message-----
>> From: owner-stds-802-3-re@IEEE.ORG
>> [mailto:owner-stds-802-3-re@IEEE.ORG] On
>> Behalf Of Hugh Barrass
>> Sent: Thursday, September 02, 2004 12:28 PM
>> To: STDS-802-3-RE@listserv.ieee.org
>> Subject: Re: [RE] What's wrong using FireWire as the home backbone?
>>
>> >What is missing from FireWire that prevents it from solving the
problems
>> of wired home networking?
>>
>> 1/ FireWire does not like to go further than 4.5m
>> 2/ FireWire does not scale well - fixed amount of bandwidth is shared
>> amongst all devices on the network.
>> 3/ FireWire is not Ethernet
>>
>> Items 1 and 2 have been addressed by enhancements to the IEEE-1394
>> specification (FireWore over CAT5 and bridging). I'm not seeing
>> quick market
>> uptake on these advances. Probably because of item 3. Ethernet
>> is popular.
>> Independent of technical capabilities, the more popular an
>> interconnect is
>> the more powerful it is. This is a basic property of networks Datacom
and
>> otherwise.
>>