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RE: PMD discussion


Are you suggesting we change our objectives?


> ----------
> From: 	Booth, Bradley[SMTP:bradley.booth@xxxxxxxxx]
> Sent: 	Thursday, June 01, 2000 5:19 PM
> To: 	'802.3ae'
> Subject: 	RE: PMD discussion
> Paul,
> You touched on a key point.  To quote you, "The norm is likely a choice
> between a small subset that is targeted for their needs."  I see this as
> applying directly to what we need to work on.  If there is something
> available from another standards body (i.e. VSR VCSELs), then I would prefer
> to leave that effort in that standards body especially if it doesn't broadly
> satisfy our criteria.  I think there is a small subset that the IEEE needs
> to standardize that we (I'm talking 100% majority) believe we should focus
> our effort on to meet our objectives while providing a small subset to
> satisfy our customer's needs.
> Cheers,
> Brad
> 		-----Original Message-----
> 		From:	Kolesar, Paul F (Paul) [mailto:pkolesar@xxxxxxxxxx]
> 		Sent:	Thursday, June 01, 2000 4:06 PM
> 		To:	'802.3ae'; 'Booth, Bradley'
> 		Subject:	RE: PMD discussion
> 		Brad,
> 		802.3z not only supported the installed base of 62.5 um
> fiber (which has two
> 		bandwidth grades), but also included 50 um fiber in two
> grades. These are a
> 		400 MHz-km grade (representing the worst installed base
> grade of 50 um) and
> 		a newer 500 MHz-km grade that allowed the SX solution to
> meet the 550 m
> 		distance objective. I don't think customers have had a
> difficult time
> 		getting GbE technologies to work in this situation. But we
> are sensitive to
> 		this issue. So recognizing the need to distinguish new MMF
> from old, Lucent
> 		has made the new fiber easily identifiable. New MMF cable
> and patch panels
> 		are distinctly color coded to distinguish them from other
> fiber types. 
> 		I cannot predict the percentage of new versus old fiber,
> since I don't have
> 		a crystal ball. But I believe it will be a significant
> amount with
> 		conversion accelerating as other fiber suppliers come on
> line. Lucent
> 		already shipped hundreds of kilometers of new MMF and we are
> still ramping
> 		up production. Also, I believe that deployment will tend to
> occur most
> 		rapidly in those customer sites that intend to use 10GbE
> equipment in the
> 		near term. So the absolute percentage conversion is not the
> key indicator to
> 		monitor, but rather the conversion occurring in 10GbE
> customers sites.
> 		When I look at the 10 port types, I see them serving several
> types of
> 		customers. I believe that it will be a rare customer that
> must make a choice
> 		between all 10 types. The norm is likely a choice between a
> small subset
> 		that is targeted for their needs. While most of the choices
> will not apply
> 		for any one customer, all of the choices have their purpose
> in serving the
> 		entire customer base. Let's not loose site of the fact that
> 802.3 is
> 		entering new market spaces. These new spaces are embodied in
> the 10 and 40
> 		km distance objectives that far exceed the scope of building
> cabling (the
> 		scope of Ethernet up to now), and PHY objectives which
> address both LAN and
> 		WAN. Larger and more diverse market spaces will naturally
> need a greater
> 		variety of solutions. 
> 		Regards,
> 		Paul Kolesar