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Re: York plans





Jonathan,

I have interspersed a couple of comments on your plans to give you some feedback
and get some discussion going.

To keep it simple, I'll delete sections with which I agree (I agree with most of
it).

Jonathan Thatcher wrote:

> Thank you Howard.
>
> We will need to have a motion to change our objectives to include this
> "resolution" to the "speed" objective. It needs to be clear if both PHYs are
> intended to support our matrix of distances, or if the WAN PHY will support
> a different set (or subset) of distances.

As I suggested (quite vehemently) in the July meeting, I believe that we already
have too many distance objectives. Coming up with a different set for the WAN
PHY, unless any of the individual objectives are SIGNIFICANTLY different is a
waste of valuable committee time. For example, the only additional distance
objective suggested over this reflector for the WAN PHY is 15 km (by Paul
Bottorff). This would yield 4 SMF distances of 2 km, 10 km, 15 km, and 40 km. Do
we really need 4 different price points to shoot at? I think not.

> Additionally, there are a couple of other things the chair would like to get
> started on:
> 2. Define a PMD template that can be used by each PHY candidate to document
> specific recommendations (based on clause 38?)

We definitely have a blurring of layers and sublayers in the PHY at 10 GbE. In
fact, we can have as many as three succeeding sub-PHYs, each including their own
PCS, PMA and PMD definitions comprising a 10 GbE PHY. Take for example a 10 GMII
interface, transceiver interface and media interface such as that proposed by
Howard Frazier et. al. in Montreal. I suggest that we separate the PHY into a
MACI (old MII), MII (transceiver module interface) and MI (media interface).
This should result in the PHY candidates differing only in their MI clauses.

> 3. Document dependencies between layers (clauses). For example: coding and
> PMDs.

Each interface may be coded or not. Coding is an integral part of each specific
interface.

--

Best Regards,
Rich

-------------------------------------------------------------
Richard Taborek Sr.    Tel: 650 210 8800 x101 or 408 370 9233
Principal Architect         Fax: 650 940 1898 or 408 374 3645
Transcendata, Inc.           Email: rtaborek@transcendata.com
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