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RE: [10GBASE-T] PAR and 5 critters




Hi Sreen,

One thing that occurs to me on this point is the difference between
theory and application. Specifically, how many process actions have to
take place within a baud time to close the loops on the DSP and what
process geometry would be required to make that timing closure?

I know that with 1000BASE-T, the theory was rock solid long before the
processes to implement it were reliable. 

Dan
HP ProCurve

> -----Original Message-----
> From: Sreen Raghavan [mailto:sreen-raghavan@vativ.com]
> Sent: Tuesday, July 29, 2003 11:52 AM
> To: 'Alan Flatman'; 'Kardontchik, Jaime'
> Cc: '[unknown]'; 'Sterling Vaden'
> Subject: RE: [10GBASE-T] PAR and 5 critters
> 
> 
> 
> Just to clarify, Vativ, Broadcom & Marvell presented capacity 
> calculations
> at the Portsmouth meeting and showed that worst-case CAT-7 
> (Class F) cabling
> had sufficient channel capacity to achieve 10Gbps throughput 
> at 100 meter
> distance. The reason for "may be possible" statement in the 
> conclusions was
> that the 3 PHY vendors felt that more work needed to be done 
> on practical
> implementation issues before the conclusion could be altered to a more
> definitive statement. 
> 
> In addition, we proved conclusively that there was NOT 
> sufficient channel
> capacity on existing CAT-5e (Class D), or CAT-6 (Class E) 
> cables to achieve
> 10 Gbps throughput.
> 
> Sreen Raghavan
> Vativ Technologies
> 
> -----Original Message-----
> From: owner-stds-802-3-10gbt@majordomo.ieee.org
> [mailto:owner-stds-802-3-10gbt@majordomo.ieee.org] On Behalf 
> Of Alan Flatman
> Sent: Tuesday, July 29, 2003 9:51 AM
> To: Kardontchik, Jaime
> Cc: [unknown]; Sterling Vaden
> Subject: RE: [10GBASE-T] PAR and 5 critters
> 
> 
> Message text written by "Kardontchik, Jaime"
> >Was any reason given why it would not run on Class F ? Was it for
> technical reasons or for marketing reasons ?<
> 
> The 3-PHY vendor presentation made in Portsmouth (sallaway_1_0503)
> calculated 49.36 Gbit/s capacity using unscaled Cat 7/Class F 
> cabling. This
> figure was reduced to 37.71 Gbit/s with worst case limits. Overall, I
> thought that this was a refreshingly realistic presentation and I
> interpreted the summary statement "Capacity calculations with 
> measured data
> indicate 10 Gigabit data transmission over 100m Cat 7 may be possible"
> (slide 16, bullet 3) as overly cautious engineering judgement.
> 
> So, what has changed since the May interim? Not the laws of physics!
> 
> Best regards,
> 
> Alan Flatman
> Principal Consultant
> LAN Technologies
>  
> 
> 
> 
>