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Re: Hari as 10 Gig Fibre Channel




Daniel,

I guess I am frustrated by the Hari association introducing a PHY predatory
device interconnect, driving out of the FC group that came to power within 802.3
under GbE.  Please see my comments highlighted.

Thank you,
Roy Bynum

"DOVE,DANIEL J (HP-Roseville,ex1)" wrote:

> Hi Roy,
>
> I kinda like the HARI interface but have not dedicated one single gate
> to it yet. Which camp does that put me in? The ones who "are upset because
> I have challenged  their perceived control of the development of 10GbE."
> or some other group not included in your characterizations?
>
> If you go back to the early days of Ethernet, you will find an AUI which
> looks sorta like a very low speed, single channel HARI interface. It was
> coded with Manchester, it had jitter requirements, it represented limits
> to anyone who might have wanted to propose a 10Mbps, NRZ scrambled PHY for
> Ethernet. In fact, some people even used that interface as a backplane
> interface in some instances as well.

The AUI for 10Base5 was for a single specific PHY.   Hari is being presented as
capable of supporting multiple PHYs, even those that are not block encoded.

>
>
> You said "I challenged their perceived view of Ethernet as a confined
> protocol, when they did not understand how Data Link protocols are used
> and what makes them functionally different." which at the minimum is a
> grandiose statement, but beyond that, is contradicted by your own complaints
> about them wanting to exceed your own narrow definition of what a MAC/PHY
> interface should be.
>

I am not sure by what you mean of something being my own narrow definition of
what a MAC/PHY interface should be.  I do know that the MAC/PHY interface
relationship that has been in place since the original 10Base5 standard.  The
HSSG asserted that they would not change the MAC functionality.  Did that
include the MAC/PHY relationship?  What about the PCS/PMA/PMD relationship that
has been defined for some time.  The way that Hari is being inserted between the
PMA and the PMD it means that the clauses that define the PCS/PMA/PMD
functionality will have to be rewritten, almost completely.

>
> As I said earlier, you don't HAVE to use HARI. If a passing majority of
> the members in this group find HARI to be useful in the standard, it will
> likely be there as an optional interface. There is no reason that you
> could not build a WAN PHY that used the proposed parallel interface for
> your own products. In fact, you could build a product with NEITHER
> interface if both are optional (likely) and you meet the MAC and PMD specs.
>
> I would personally like to see more technical debate and a little less of
> the poorly constructed conspiracy theories. I think the group can greatly
> benefit from your technical expertise on a wide range of matters before
> us.
>

What concerns me is that the technical debate is over an implementation practice
that goes way beyond 802.3.  I know that it will have far reaching implications
beyond the simple device interconnect that it is being advertised as.  I think
that the people that are introducing Hari are smart enough to know this.  THAT
is what is bothering me!

>
> Best Regards,
>
> Dan Dove
> ___________     _________________________________________________________
> _________    _/    ___________  Daniel Dove         Principal Engineer __
> _______     _/        ________  dan_dove@xxxxxx     LAN PHY Technology __
> _____      _/           ______  Hewlett-Packard Company                __
> ____      _/_/_/ _/_/_/  _____  Workgroup Networks Division            __
> ____     _/  _/ _/  _/   _____  8000 Foothills Blvd. MS 5555           __
> _____   _/  _/ _/_/_/   ______  Roseville, CA 95747-5555               __
> ______        _/      ________  Phone: 916 785 4187                    __
> _______      _/      _________  Fax  : 916 785 1815                    __
> __________  _/ __________________________________________________________
>
> > -----Original Message-----
> > From: Roy Bynum [mailto:rabynum@xxxxxxxxxxx]
> > Sent: Sunday, November 28, 1999 8:32 PM
> > To: rtaborek@xxxxxxxxxx; rtaborek@xxxxxxxxxxxxx
> > Cc: HSSG
> > Subject: Re: Hari as 10 Gig Fibre Channel
> >
> >
> >
> > Rich,
> >
> > Perhaps the NCITS TC T11 is the correct forum to standardize
> > on Hari.  Please remove it as a
> > specific functional standard within P802.3ae.  Please make it
> > possible for the people
> > working on the PHYs to apply the functional implementations
> > that are needed for the specific
> > PHYs.  According to the 802.3 model the PHY specific coding
> > occurs within the PCS, not the
> > PMD.  Applying Hari between the PMA and PMD violates that model!
> >
> > Hari is only a requirement for those people that decided on
> > the PHY of choice before the
> > HSSG got a chance to vote on it/them, and jumped the gun on
> > their ASICs.  As far as I am
> > concerned those people can implement anything they want, as
> > long as they do not make it part
> > of the P802.3ae standard.
> >
> > Right now several people are upset because I have challenged
> > their perceived control of the
> > development of 10GbE.  I have brought disorder where they
> > thought that they had imposed
> > order, their order. They are correct.  I challenged their
> > perceived view of Ethernet as a
> > confined protocol, when they did not understand how Data Link
> > protocols are used and what
> > makes them functionally different.  They did not understand
> > that the developers of GbE
> > brought the disorder first by crossing the boundary between
> > confined LAN application and
> > unconfined WAN application.
> >
> > The application of Fiber Channel technology and functionality
> > helped cause that disorder.
> > Most FC applications have response timing limitations (100x
> > ms) at the application level,
> > which makes most FC implementations Local.  Putting Fiber
> > Channel under applications that do
> > not have those same response timing limitations removes the
> > Local only limitation.  FC is
> > designed for campus facilities, using privately owned fiber.
> > The GbE people incorrectly
> > thought that they too were making GbE into a Local only
> > protocol.  They did not understand
> > that the full duplex nature of the original Ethernet, applied
> > through 100mb 802.3 was what
> > made it truly Local only.  Even the electrical full duplex
> > 100BT can be used across a long
> > haul fiber system by putting it into an optical transducer.
> > Full duplex 100FX has been used
> > across long distances with wavelength/power transducers.  GbE
> > is taking off as a leased
> > fiber WAN protocol, without service operations support.
> >
> > I am not the cause of the disorder here.  The people that did
> > not fully understand the
> > implications and applications of what they were doing are the
> > cause of the disorder.  Please
> > do not codify that disorder within P802.3ae.
> >
> > Thank you,
> > Roy Bynum
> >
> >
> >
> > Rich Taborek wrote:
> >
> > > Earlier this week, NCITS Technical Committee T11, chartered
> > with development of the
> > > Fibre Channel suite of standards, approved a project
> > proposal to extend FC protocol to
> > > an operating speed of approximately 10 Gbps, following the
> > lead of the IEEE 802.3
> > > committee. The project proposal, entitled FC-PI-2 to
> > identify the documentation effort
> > > associated with the 10 Gig FC project, was approved by T11
> > Letter Ballot on Monday,
> > > November 22, 1999 by a vote of Yes63-No02-NotVoting10 (4
> > yes ballots included comments).
> > > Further details and comments can be found via the T11 web
> > site @ http://www.t11.org/ by
> > > clicking on "ballots", then "closed ballots", then "T11
> > Ballot - FC-PI-2 PP approval".
> > > The next step is to forward the project proposal to NCITS,
> > T11's parent body. The
> > > FC-PI-2 project proposal can be found @
> > > ftp://ftp.t11.org/t11/admin/project_proposals/99-521v1.pdf.
> > >
> > > An introductory meeting to kick off the 10 Gig FC project
> > will be held during the next
> > > T11 Plenary week on December 8, 1999 at the Peppermill
> > Hotel in Reno, NV, USA, during
> > > the joint session of the T11.2 (FC Physical Layer) and
> > T11.3 (FC Interconnects)
> > > committees. This meeting is scheduled for 1:00-2:00 PM.
> > Further T11 Plenary week details
> > > can be found by clicking on "meetings" from the T11 home page.
> > >
> > > --
> > > Best regards,
> > > Rich
> > >
> > >   ----------------------------------------------------------
> > >
> > > Richard Taborek Sr.   1441 Walnut Dr.   Campbell, CA 95008 USA
> > > Tel: 408-330-0488 or 408-370-9233           Cell: 408-832-3957
> > > Email: rtaborek@xxxxxxxxxx or rtaborek@xxxxxxxxxxxxx
> >