|
The term ISO uses is
"Balance Cabling" (Clause 6 of 11801, 2002) and TIA uses "Horizontal
Cabling", which is used in the Data Center document to identify the cabling. I
have been reminded often by others that we should use ISO
designations.
Terry
I agree that "on
horizontal structured cabling" probably needs a tweak. It could
possibly be interpreted as requiring 100 m operation for all supported
media. As Terry points out, it doesn't really reflect the data center as a
focus of broad market potential.
Regards,
Pat
Pat – thanks for
the clarifications – I’d missed the fact that speed wasn’t mentioned (must
be still suffering from Italian jet-lag). Scopes should be broad but
clear. The CX4 scope is probably a good model. “based on” is
different than saying it must implement it. (under this scope a
10GBASE-CX4 could incorporate other line codes, etc.) Similarly
“working over the wiring types used in structured cabling” is a bit
different than the text as written, which enters into a more specific
description of “structured cabling” (we had a little discussion in
Italy where some had a
very narrow understanding of what that means).
I’ll have to think
a little about an alternative, but I think we’re on the same principle:
speed & wiring types define 10GBASE-T, but the detailed description is
for the objectives.
-----Original
Message-----
From:
pat_thaler@agilent.com
[mailto:pat_thaler@agilent.com]
Sent: Wednesday, September
24, 2003 3:28 PM
To:
George
Zimmerman; dan.dove@hp.com;
btolley@cisco.com; bradley.booth@intel.com; stds-802-3-10gbt@ieee.org
Subject: RE: [10GBASE-T] Proposed
modification to PAR scope
I think Dan's suggestion went
too far - very specific media descriptions (like references to 11801) have
always been for the objectives rather then the PAR. On the other hand, the
existing scope is much more broad than previous
projects:
The scope of this project
is to specify additions to and appropriate modifications of IEEE Std 802.3
(including all approved amendments and corrigenda) to add a copper Physical
Layer (PHY) specification.
Howard's suggested
scope:
Specify a Physical Layer (PHY)
for operation at 10 Gb/s
on horizontal
structured copper cabling, using the existing
Media Access
Controller, and with extensions to the appropriate
physical layer
management parameters, of IEEE Std 802.3
The scope of this project is to specify additions
to and appropriate modifications of IEEE Std 802.3 as amended by IEEE
Std 802.3ae-2002 (and any other approved
amendment or corrigendum) to add a copper Physical Medium Dependent (PMD)
option for 10 Gb/s operation, building upon the
existing 10GBASE-X Physical Coding Sublayer (PCS) and 10 Gigabit Attachment
Unit Interface (XAUI)
specifications.
The CX4 scope text is much more
similar to Howard's suggested scope. Both have a statement about
the speed. I can't recall any scope statement we have done for a PHY project
that omitted mention of speed. The CX4 scope doesn't say anything about
the type of copper, but it specifies that the PHY will be based on the
X PCS and the XAUI specs which limits it pretty clearly. For 10GBASE-T, the
intent to work over the wiring types used in structured cabling and the 10
Gbit/s speed are the defining factors.
Look at it this way. IEEE Std
802.3 already has many copper Physical Layer specifications. Therefore the
job listed in the current scope statement has already been done. If the PAR
is approved with the current scope, the scope will be published by the IEEE.
How would a reader seeing that scope know what the project was about and
whether they were interested? Howard's scope is a more clear statement of
what we want to do.
If something in Howard's scope
is too confining, then please propose an alternative that is reasonably
descriptive of the particular nature of this project - not something that
could describe 5 or more other projects we have already
done.
|