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RE: Unified PMD vs. Unified PHY




As opposed to the UniPHY being an attempt to shoehorn the LAN PHY into the
WAN PHY, I think the UniPHY is a great attempt to standardize the pieces
that are similar between the two PHYs thereby reducing the effort.

Walt


> -----Original Message-----
> From: Roy Bynum [mailto:rabynum@mindspring.com]
> Sent: Sunday, March 19, 2000 1:51 PM
> To: rtaborek@nserial.com; HSSG
> Subject: Re: Unified PMD vs. Unified PHY
> 
> 
> 
> Rich,
> 
> The original compromise was to have separate LAN and WAN 
> PHYs.  Now a group
> of people is trying to compromise on the compromise by 
> compromising the best
> features of both of the separate PHYs in a continuing attempt 
> to justify an
> 8B10B precoding to everything else by calling it another 
> name.  This is the
> same problem that was had with the "hari" proposals.  The "UniPHY" as
> proposed is nothing more than the original 10.00 Gb 8B10B LAN 
> PHY attempting
> to "shoe horn" itself into the WAN PHY and being an additional 3% less
> efficient doing it.
> 
> I know that you have an emotional attachment to 8B10B.  I 
> know that at least
> one large LAN vendor has already done an ASIC using 8B10B out 
> of the MAC.
> Not using 8B10B does not preclude the LAN vendor from having 
> his LAN PHY
> based on block encoding, 8B10B or 64B/66B; while allowing the 
> WAN vendors
> from having a non-8B10B solution.  Please do not presume that 
> one solution
> will be best for all implementations.
> 
>  Thank you,
> Roy Bynum
> 
> 
> ----- Original Message -----
> From: Rich Taborek <rtaborek@nSerial.com>
> To: HSSG <stds-802-3-hssg@ieee.org>
> Sent: Sunday, March 19, 2000 12:17 AM
> Subject: Re: Unified PMD vs. Unified PHY
> 
> 
> >
> > Roger,
> >
> > The problem we're having is that the leading proposals for 
> the LAN, WAN
> and Uni
> > PHY's are all proposing putting different things on the 
> wire. This doesn't
> help.
> > Therefore, the UniPHY may be the "compromise" solution 
> since it would
> result in
> > one definition of what's on the wire.
> >
> > Best Regards,
> > Rich
> >
> > --
> >
> > Roger Ronald wrote:
> > >
> > > If you ask a question that only considers benefits and 
> not costs, the
> answer will be
> > > skewed and (IMHO) fairly meaningless.
> > >
> > > Is one PHY better than two? Sure.
> > >
> > > Is one PHY better than two if the cost for the part is tripled.
> Absolutely not!
> > >
> > > How about if having both PHY capabilities increases the 
> power budget by
> a factor of
> > > 50% over each individually?
> > >
> > > If a part can meet the standards for operating in the 
> mode of operation
> that
> > > the vendor chooses to support, it should be acceptable. 
> It should not be
> unacceptable
> > > just because it might be "better" if it could also do 
> other things.
> > >
> > > If someone wants to make a LAN only PHY, why not let them?
> > > If someone wants to make a WAN only PHY, why not let them?
> > > If someone wants to make a UNI PHY, why not let them?
> > >
> > > Standards groups (again IMHO) should define standards, not
> implementations. I.e.
> > > define what is on the wire, not how it gets there.
> > >
> > > RR
> > > ----- Original Message -----
> > > From: Rich Taborek <rtaborek@nSerial.com>
> > > To: HSSG <stds-802-3-hssg@ieee.org>
> > > Sent: Tuesday, March 14, 2000 4:41 PM
> > > Subject: Re: Unified PMD vs. Unified PHY
> > >
> > > >
> > > > Bruce,
> > > >
> > > > Well said! This was also my interpretation of the 
> survey results. If
> there were
> > > > only one question on the survey, UniPHY vs. separate 
> LAN and WAN PHY,
> I believe
> > > > that the survey results would be the same (i.e. 
> strongly in favor of a
> UniPHY).
> > > >
> > > > Best Regards,
> > > > Rich
> > > >
> > > > --
> > > >
> > > > Bruce Tolley wrote:
> > > > >
> > > > > At 08:33 AM 3/14/00 -0600, Roy Bynum wrote:
> > > > > >  I think that the original compromise and
> > > > > >the objectives as stated are correct, there needs to 
> be seperate
> LAN and WAN
> > > > > >PHYs.
> > > > >
> > > > > Roy:
> > > > >
> > > > > I think in the first part of your statement you hit 
> the nail on the
> head.  Goal #9 (Define two families of PHYs) was a
> > > compromise that came out of several meetings that was aided by the
> bridge diagram originally proposed by Howard Frazier.
> > > > >
> > > > > Many folks have since expressed displeasure with the idea of a
> bridge but the picture gave the members of the study group a way
> > > to understand and bound the problem.
> > > > >
> > > > > The goal of two PHYs agreed upon in York was as much political
> statement as it was a technical statement. There was a strong
> > > feeling up to the meeting in York of the need to limit 
> the problem,
> define the goals, and get on with the work.
> > > > >
> > > > > It was always clearly stated that the goals were not 
> written in
> stone and we might come back to revise them.
> > > > >
> > > > > Given the basis of the findings from survey conducted 
> by Jonathan, I
> conclude that there is strong support among the members of
> > > the task force to seriously investigate the concept of the UniPHY.
> > > > >
> > > > > Bruce
> > > >
> > > > -------------------------------------------------------
> > > > Richard Taborek Sr.                 Phone: 408-845-6102
> > > > Chief Technology Officer             Cell: 408-832-3957
> > > > nSerial Corporation                   Fax: 408-845-6114
> > > > 2500-5 Augustine Dr.        mailto:rtaborek@nSerial.com
> > > > Santa Clara, CA 95054            http://www.nSerial.com
> >
> > -------------------------------------------------------
> > Richard Taborek Sr.                 Phone: 408-845-6102
> > Chief Technology Officer             Cell: 408-832-3957
> > nSerial Corporation                   Fax: 408-845-6114
> > 2500-5 Augustine Dr.        mailto:rtaborek@nSerial.com
> > Santa Clara, CA 95054            http://www.nSerial.com
> >
> >
>