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Re: [802.3ae] a bit concerned...


As a representative of both a PHY component and
PMD/transceiver/transponder vendor for both P802.3ae LAN and WAN PHYs
I'd like to offer the following in rebuttal to your assertions:

1) The P802.3ae WAN PHY and its associated PMD, is, for all practical
purposes, identical to that of SONET OC-192c and SDH VC-4-64c. Since the
latter devices have been in the market for quite some time, and designed
for longer reach applications than those specified in P802.3ae
objectives, I believe that technical feasibility is proven. Economic
feasibility... well that's another issue. However, it is unrelated to
the issue at hand;

2) P802.3ae PMD objectives stop at supporting link distances of: "At
least 40 km over SMF". These are "slam dunk" distances for most SONET
equipment. In fact, changing "At least 40 km" to "80 km" is still a slam
dunk for SONET. This says to me that existing SONET PHY and PMD specs,
including optical and jitter specs, should be adequate, and are probably
too demanding for all P802.3ae applications. It seems to me that
P802.3ae PHY and PMD specifications, being more demanding than those of
SONET are inconsistent with intended P802.3ae applications. This is true
for both LAN and WAN PHY types. I am submitting a TR comment against
D3.1 to resolve this issue.

3) I have no clue at to what you're alluding too when you say: "The
issue that I have seen is stability at the higher signaling rate of the
LAN PHY". I believe that you are a staunch supporter of Optical
Transport Network (e.g. OTN, G.709, ASON, etc.) including the associated
PHY and PMD signaling rates in the range of 10.7 to 12.5 GBaud. Please
correct me if I am misinformed and you do not support these OTN
activities. The 10.3125 GBaud signaling rate of the P802.3ae LAN PHY is
again a slam dunk relative to OTN signaling, especially in consideration
of the much shorter reach and point-to-point only topology applications
for the LAN PHY. Bottom line is that the 10 Gigabit Ethernet LAN PHY is
the latest, an likely strongest, contender for 10G MAN/metro

Best Regards,

Roy Bynum wrote:
> Brad,
> As a customer that gets information individually from the vendors,
> including transceiver vendors, I have concerns over the discrepancy with
> OEM vendors that are pushing to develop the LAN PHY early instead of the
> WAN PHY and the ability of the transceiver vendors ability to deliver the
> WAN PHY PMD earlier than the LAN PHY PMD.  The issue that I have seen is
> stability at the higher signaling rate of the LAN PHY.  I am saying this in
> general context, not commenting on any one or group of  system, component,
> or PMD vendors.
> This could make for some discrepancies in the ability to do feasibility
> and/or inter-operability testing, perhaps even in September.
> Thank you,
> Roy Bynum
> At 03:37 PM 7/2/01 -0700, Booth, Bradley wrote:
> >Just so everyone in the Task Force is aware, we have had very low volume of
> >comments submitted so far.  I do have some concern as we contemplate moving
> >forward to Sponsor ballot.  My primary concern is that of demonstrated 10GbE
> >interoperability.  Without some level of interoperability work, we may not
> >have a draft that has been reviewed and debugged as extensively as it needs
> >to be.  The lack of comments along with the lack of demonstrated product is
> >of grave concern to me.
> >
> >Thank you,
> >Brad
Richard Taborek Sr.                     Intel Corporation
XAUI Sherpa                    Intel Communications Group
3101 Jay Street, Suite 110         Optical Products Group
Santa Clara, CA 95054           Santa Clara Design Center
408-496-3423                                     JAY1-101
Cell: 408-832-3957          mailto:rich.taborek@xxxxxxxxx
Fax: 408-486-9783