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Re: PMD Objectives


Thanks for the feedback.

I'm currently involved with a number of large Internet Data Center
projects. Unlike traditional computer room and data center
constructions, where the computing environment is typically
dedicated to the use of a single corporate entity,  the Internet
Data Center and central office services multiple customers with
multiple network infrastructure access requirements i.e.,
bandwidth, data storage, security, etc...

The design drivers for the engineering or reengineering of these
installations are:

1. Time- Internet time is short. Market penetration is at the speed of
+++Products that reduce the time to build are used.
+++Products that reduce downtime for fault isolation are used
(cable management, labeling).

2. Security-is everywhere.
+++Products that help provide circuit isolation and monitoring
(cable management, labeling).

3. Space- is at a premium. In-building network expansions is constrained by
physical space.
+++Products that are compact are used.

4. Bandwidth is everything.

The 300 meters covers the building "riser" and a high percentage of campus



----- Original Message -----
From: Roy Bynum <rabynum@xxxxxxxxxxxxxx>
To: Chris Diminico <cd@xxxxxxxxxxxxxx>; <stds-802-3-hssg@xxxxxxxx>
Sent: Thursday, August 10, 2000 9:57 AM
Subject: Re: PMD Objectives

> Chris,
> You had sent this table to me asking for my input before you sent it to
> reflector in general.  I have not had time to do that before you sent it
> out.  I have some very specific issues with your table.  In the first
> place, as I have stated to you before, I do not believe that there will be
> a lot of patch panels in use except for extended distance and "riser"
> applications.  In situations where patch panels are used, the effective
> distance is greater because of the attenuation of the connectors in the
> patch panels.
> What are you referring to as far as "Backbone + Equipment Cable"?  Other
> than a few building "riser" and campus applications, I see little use for
> the 300m distance objective.  WAN PHY (WIS) interconnections will either
> at the < 50m distance or at the 10km distance, depending on whether it
> be used with DWDM and/or Optical Switching.
> I would expand the distance of all of your 30m applications to 50m.  The
> distinction should be between overbuilding existing data rooms with 10GbE
> which is very near term and the building of data rooms exclusively with
> 10GbE which is more long term.
> Thank you,
> Roy Bynum
> At 02:15 PM 8/9/00 -0400, Chris Diminico wrote:
> >As I pointed out in e-mail to Jonathan, for completeness, we need to
> >state all of the relevant application spaces and associated distances in
> >order to address the applicability of the current set of distance
> >and
> >further the PMD discussion.
> >
> >The table attached is my attempt at characterizing the cabling distances
> >versus
> >10 Gb/s application space. The customer  premise cabling lengths are
> >complete
> >(by survey and reference). I am collecting information on the cabling
> >lengths associated with
> >the central office and the data center. The lengths provided for the data
> >center and central office are reasonable target values which may be
> >based on further study. Any help would be
> >appreciated.
> >
> >
> >Regards,
> >
> >  Chris Di Minico
> >Cable Design Technologies (CDT) Corporation
> >Director of Network Systems Technology
> >Phone: 800-422-9961 ext:333
> >e-mail: cd@xxxxxxxxxxxxxx
> >