Re: [10GBT] Channel models and frequency range and other details of measureme...
Thanks for the information.
cell: (650) 704-7686
office: (408) 653-2235
From: stds-802-3-10gbt@IEEE.ORG on behalf of Chris DiMinico
Sent: Wed 6/23/2004 6:08 PM
Subject: Re: [10GBT] Channel models and frequency range and other details of measureme...
TR42 met the 2nd week in June. At the TR42 plenary two IEEE liaison letters
were drafted providing
the status of the two TR42 10GBASE-T related projects (project outline
below). My understanding is that
the letters will be sent to 802.3 this week with copies to Brad. The first
draft of TSB-155 (outlined below) will
be attached to the liaison which includes changes to the Class E extrapolated
limits for NEXT, PSNEXT and RL.
1. Project PN-3-0134: Development of a Telecommunications Systems Bulletin
(TSB-155). The TSB guidelines will
provide additional information on the extended frequency transmission
performance of category 6 cabling
from 250 MHz up to 625 MHz. It also addresses alien crosstalk and provides
additional guidelines for
field test equipment and field test methods and alien crosstalk mitigation.
2. SP-3-4426-AD10: Augmented Category 6 cabling >> The project is to develop
cabling and component
specifications and test procedures to support the operation of IEEE 802.3
10GBASE-T over 100 meters
of structured balanced twisted-pair copper cabling.
B: Frequency range:
The motion to limit the upper frequency range to 500MHz for cabling
parameters in the link segment specifications
was supported by the majority at the Interim Meeting May 25-27, 2004 Long
Task Force Yes 32 No 25 A 6
802.3 Voters Yes 18 No 7 A 3
In the group voting no I recorded at least 6 that asked for measurement data
to 625 MHz and would be willing
to relax the link segment specifications as long as they were provided the
measurement data .
One option is to agree to continue to providing measurement data to 625
MHz and relax the link segment specification to 500 MHz.
The reduction in the upper frequency range to 500 MHz has immediate positive
impact on reducing the complexity
and difficulty of the phy implementation including the cabling
specifications, the cabling measurement specifications,
and the cabling field testing specifications.
ps..if your not looking for controversy don't ask controverial questions.
In a message dated 6/23/2004 4:39:40 PM Eastern Standard Time,
At the last meeting in Long Beach, there was mention of a TIA meeting and an
ISO meeting. I don't recall the exact dates but I believe the TIA meeting
should be over by now and possibly the ISO meeting too.
1) Can any of the folks who were at either of those meetings summarize any
items that may be relevant to the 10GBASE-T task force? What I am asking for
will not replace any official liaison letter we get so please don't flame all
over this request. If official liaison letters have been received, can we get
copies of those before our July meeting?
2) Were there any recommendations made by either of these bodies requesting
us to change our NEXT models or return loss models? If the appropriate
officials of either of these organizations are on this task force, can they provide
the official response?
3) Also, looking through the proposals on the table right now, the proposed
symbol rates now range from 810Msym/sec to 1000Msym/sec.
Given this, can we provide any guidance to the cabling industry on what
frequency range we would like to see measured data?
4) For those of you planning to run time domain simulations, is there a
preference on the frequency resolution of the measurements?
The transformer data has been provided in non-uniform frequency intervals -
starting at roughly 14Khz spacing near DC and ~25Mhz near 600Mhz.
Some of the cabling data has been provided at 625Khz frequency spacing. Other
cabling data has been provided at 750Khz frequency spacing. Any
recommendations on a common frequency resolution? If so, what spacing?
cell (650) 704-7686
office (408) 653-2235
fax (408) 844-8187
2953 Bunker Hill Lane, Suite 204
Santa Clara, CA 95054