Re: Going the distance
- To: Bruce_Tolley@xxxxxxxx, HSSG <stds-802-3-hssg@xxxxxxxx>
- Subject: Re: Going the distance
- From: Rich Taborek <rtaborek@xxxxxxxxxxxxxxxx>
- Date: Wed, 30 Jun 1999 10:33:54 -0700
- Organization: Transcendata, Inc.
- References: <882567A0.005915D1.00@xxxxxxxxxxxxxxxxxxxxxxx>
- Reply-To: rtaborek@xxxxxxxxxxxxxxxx
- Sender: owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
Technical feasibility should not be a concern. We WILL be able to stretch this goal.
This assertion is based on the use of single-mode fiber and long wavelength (1300 or
1550 nm) lasers. These PMD components used together possess attenuation and
dispersion characteristics which can easily exceed this goal. The existence proof is
OC-192 links. The caveat is that I don't expect components that can support
distances of 100 or even 20 km at 10 Gbps to be priced the same as those capable of
going 2-3 km. Expect higher laser costs when going farther. Economic feasibility
must be considered when attempting to significantly exceed distance goals. On the
other hand, 5, 10 and even 15 km may be achievable at a favorable relative cost.
> The point has been made before that today customers are already going 5 to 10 Km
> with 1000BASE-LX. There should be no debate that it is a market requirement to
> go 5 to 10 km with 10 GbE.
> While I am willing to consider accepting a conservative 2 to 3 km goal as the
> official goal of the project, we need to acknowledge that this is a
> conservative goal and, as we get on with the work of the project , we should
> investigate whether we can stretch this goal..
> Bruce Tolley
> 3Com Corporation
> Rich Taborek <rtaborek@xxxxxxxxxxxxxxxx> on 06/29/99 05:01:32 PM
> Please respond to rtaborek@xxxxxxxxxxxxxxxx
> Sent by: Rich Taborek <rtaborek@xxxxxxxxxxxxxxxx>
> To: Howard Frazier <hfrazier@xxxxxxxxx>, HSSG <stds-802-3-hssg@xxxxxxxx>
> cc: (Bruce Tolley/HQ/3Com)
> Subject: Re: Going the distance
> I will gladly accept your suggestion of removing the portion of the
> motion in parenthesis as a friendly amendment post-haste given your
> support of this motion as a seconder.
> - Rich
> Howard Frazier wrote:
> > The more I think about it, the more I like the idea of adopting the
> > 802.3z link distance objectives for 10 Gig. We should remember that
> > we are still in the study group phase, trying to scope out a project.
> > We can always adjust the objectives later.
> > Let me therefore state my support for Rich's proposed motion:
> > > "Support the premises cabling plant distances as specified in
> > > ISO/IEC 11801"
> > >
> > > The distances supported in ISO/IEC 11801 are:
> > >
> > > 100 m for horizontal cabling (applicable to copper, MMF, SMF)
> > >
> > > 550 m for vertical cabling: (applicable to SMF and possibly MMF)
> > >
> > > 2-3 km for campus cabling: (applicable to SMF)
> > Rich, I would encourage you to drop the parenthesis.
> > If we adopt this objective, we can make progress on the rest of the
> > work we need to do as a study group. As was demonstrated in 802.3z,
> > we will need to review the objectives periodically, and revise them
> > if there is consensus to do so.
> > Howard Frazier
> > Cisco Sytems, Inc.
Richard Taborek Sr. Tel: 650 210 8800 x101 or 408 370 9233
Principal Architect Fax: 650 940 1898 or 408 374 3645
Transcendata, Inc. Email: rtaborek@xxxxxxxxxxxxxxxx
1029 Corporation Way http://www.transcendata.com
Palo Alto, CA 94303-4305 Alt email: rtaborek@xxxxxxxxxxxxx