RE: XAUI, SFF connectors
Chris,
I may be mistaken, but the individuals that I most identify with "XAUI" and
the pervious "HARI" are the individuals that have made the initial
presentations. Most notably of these is a person that works for a very
large system vendor that has an issue with form factor, the need to support
large PC boards. The other most memorable individual now works for a major
chip manufacturer, an executive of which has, on this reflector, admitted
to having the agenda of "sharing" the technology with competing
protocols/standards that the chip manufacturer has a major interest in.
Thank you,
Roy Bynum
At 09:18 AM 7/31/00 -0600, Chris Simoneaux wrote:
>Maybe someone can help me understand this....
>
>Was XAUI initially driven by:
> a. IC vendors as an effort to reduce the number of leads on the
>chips?
> b. PC board vendors to reduce the number, and complexity of traces
>on a board
> c. OEMs for the reasons a. and/or b.
> d. Other?
>
>Thanks,
>Chris
>
>
>-----Original Message-----
>From: Joel Goergen [mailto:joel@xxxxxxxxxxxxxxxxxxx]
>Sent: Friday, July 28, 2000 9:26 AM
>To: stds-802-3-hssg@xxxxxxxx
>Subject: Re: XAUI, SFF connectors
>
>
>
>Sabato,
>
>I agree with your comments stated below. Though I still don't believe 8b10b
>was
>the best choice for XUAI, I strongly believe XUAI is necessary and I support
>it
>completly. Thanks for taking the time to get the points across.
>
>Take care
>Joel
>-----------------
>
>"Simon L. Sabato" wrote:
>
> > Roy,
> >
> > I'm quite happy to have go through the "growing pains". If this means
> > beating FC and IB to 10G rates, that means that some of their applications
> > will migrate to Ethernet. As they climb on the XAUI bandwagon, it will
>only
> > serve to increase the market for many of the components (retimers, etc)
>that
> > go into 10G Ethernet boxes, as well as increasing the amount of expertise
>in
> > the core technologies.
> >
> > Imagine a world where there's a limited number of experts who can put
> > together a high speed interface such as XAUI (this shouldn't be very
>hard...
> > just look around you). Now, imagine two possible scenarios. The first in
> > which 10GE, FC, and IB all have different physical layers, and the limited
> > number of experts is split up into three groups. The second in which all
> > have very similar physical layers and the limited number of experts work
>on
> > parts that could be used in each application. Now, you tell me, which one
> > of the above scenarios gives the end customer the lowest cost, highest
> > quality product?
> >
> > You seem to assume that if FC and IB reuse our technology then we are
> > "paying for this and the other technologies are the actual beneficaries".
> > You're partially right, we are paying for the development -- that's the
> > price of being on the cutting edge. Trailing technologies will always
> > leverage the latest technology.
> >
> > But your continuous assertions imply that we are paying for development of
> > XAUI features that *are not useful in 10GE*. These assertions need to
>stop
> > or backed up with some information that makes sense. I have yet to see
>this
> > information. I've seen a lot of explanations from varied people at
>various
> > companies explaining the benefits of XAUI. I find it odd that you can be
>so
> > sure that *no-one* needs something. It's easy to know what *you* need,
>but
> > how can you speak for everyone else?
> >
> > In summary, I see XAUI as a way to use a common technology across various
> > applications due to the shared market and shared expertise. Using TTL
> > voltage levels across various applications is a *good thing* even if, say,
> > it wasn't particularly ideal for each one. The only argument against this
> > is that we are saddling XAUI with burdens from other standards, which you
> > claim but cannot substantiate.
> >
> > -Simon Sabato
> > -Manager, Product Architecture
> > -InterNetworking Operation, Intel Corp.
> >
> > P.S. Speaking of what is "costing" the 10GE group, constant discussion on
> > subjects that are closed costs us all. It just cost me twenty minutes to
> > write this message, and a whole lot to read all the others.
> >
> > > -----Original Message-----
> > > From: owner-stds-802-3-hssg@xxxxxxxx
> > > [mailto:owner-stds-802-3-hssg@xxxxxxxx]On Behalf Of Roy Bynum
> > > Sent: Thursday, July 27, 2000 2:55 PM
> > > To: stds-802-3-hssg@xxxxxxxx
> > > Subject: Re: XAUI, SFF connectors
> > >
> > >
> > >
> > > Ali,
> > >
> > > You may have it backwards. XAUI is not presented as a back plane
> > > technology. XAUI is presented as a copper etch extension
> > > contained only on
> > > the PCB.
> > >
> > > The people that would be benefiting from the technology sharing is Fibre
> > > Channel and Infiniband. At present, those groups do not have any mature
> > > technology at 10Gb. Have you not noticed the reflector traffic
> > > discussing
> > > how this technology should be developed. If Fibre Channel and Infiniband
> > > had demonstrated 10Gb parallel interfaces already, then it would be a
> > > different situation. The original presentations on "Hari" and
> > > then "XAUI"
> > > would have been very different; they would have referenced previous
> > > implementations. If it were mature technology from the other
> > > environments,
> > > then the questions of "striping" and "jitter" would have been answered
> > > already and not be topics of discussion here. The fact that these are
> > > topics of discussion is another proof that it is P802.3ae that is paying
> > > for this and the other technologies are the actual beneficiaries.
> > >
> > > It will be P802.3ae that will be paying for the technology
> > > development and
> > > go through the "growing pains" to mature the technology. As a
> > > customer, I
> > > find paying for the development of a technology specific for
> > > other markets
> > > to be difficult to accept in order to get the technology that I
> > > do want and
> > > am willing to pay for. I also find it uncomfortable and insecure to
> > > attempt to depend on a technology that does not have a development and
> > > maturation history.
> > >
> > > Thank you,
> > > Roy Bynum
> > >
> > > At 09:03 AM 7/26/00 -0700, ghiasi wrote:
> > >
> > > >Hi Roy
> > > >
> > > > > X-Sender: rabynum@xxxxxxxxxxxxxxxxxx
> > > > > Date: Mon, 24 Jul 2000 14:26:27 -0500
> > > > > To: ghiasi <Ali.Ghiasi@xxxxxxxxxxx>
> > > > > From: Roy Bynum <rabynum@xxxxxxxxxxxxxx>
> > > > > Subject: Re: XAUI, SFF connectors
> > > > > Mime-Version: 1.0
> > > > >
> > > > > Ali,
> > > > >
> > > > > I agree, it should be possible to put more than one 10GbE
> > > port on a PCI
> > > > > form factor. I agree, XAUI is a good technology to get from
> > > the backplane
> > > > > to the ASIC.
> > > >
> > > >How do you expect 10Gig Ethernet data is getting from ASIC through
> > > >backplane and to the I/O?
> > > >
> > > > >What I object to is hijacking the Ethernet standard to
> > > > > develop technology that is not for Ethernet, but for generic system
> > > > vendors
> > > > > using Infeneband and Fibre Channel.
> > > >
> > > >Gigabit Ethernet physical layer was based on Fiber Channel, it is
>called
> > > >leveraging or cost amortization. Also Infeneband is written as
> > > >"Infiniband".
> > > >
> > > > >If possible, I am going to make the
> > > > > XAUI people pay for their pushing the cost of that technology
> > > development
> > > > > into the P802.3ae standard.
> > > >
> > > >Since we are going to save you some buck, I hope you don't mind instead
> > > >you paying us.
> > > >
> > > >Thanks,
> > > >
> > > >Ali Ghiasi
> > > >Sun Microsystems
> > > >
> > > > >
> > > > > Thank you,
> > > > > Roy Bynum
> > > > >
> > > > > At 10:33 AM 7/24/00 -0700, you wrote:
> > > > > >Hi Roy
> > > > > >
> > > > > > > X-Sender: rabynum@xxxxxxxxxxxxxxxxxx
> > > > > > > Date: Mon, 24 Jul 2000 11:23:15 -0500
> > > > > > > To: rtaborek@xxxxxxxxxxxxx, HSSG <stds-802-3-hssg@xxxxxxxx>
> > > > > > > From: Roy Bynum <rabynum@xxxxxxxxxxxxxx>
> > > > > > > Subject: Re: XAUI, SFF connectors
> > > > > > > Mime-Version: 1.0
> > > > > > > X-Resent-To: Multiple Recipients
> > > <stds-802-3-hssg@xxxxxxxxxxxxxxxxxx>
> > > > > > > X-Listname: stds-802-3-hssg
> > > > > > > X-Info: [Un]Subscribe requests to majordomo@xxxxxxxxxxxxxxxxxx
> > > > > > > X-Moderator-Address: stds-802-3-hssg-approval@xxxxxxxxxxxxxxxxxx
> > > > > > >
> > > > > > >
> > > > > > > Rich,
> > > > > > >
> > > > > > > What need does an interface card have for SFF connectors that
>can
> > > > only put
> > > > > > > one optical port within a 13 inch copper etch radius?
> > > > > >
> > > > > >It should be very reasonable to put two to four 10 Gig port
> > > on a PCI form
> > > > > >factor card.
> > > > > >
> > > > > > From what you and
> > > > > > > others are making us believe, the form factor
> > > requirements for 10GbE
> > > > > > are so
> > > > > > > large that SFF connectors are a non-issue. If 10GbE
> > > interfaces are
> > > > going
> > > > > > > to be so dense that we will need SFF connectors, why did we need
> > > > XAUI? I
> > > > > > > can't see how you would need both.
> > > > > >
> > > > > >XAUI provides high through put 3.125 Gb/s from two ASIC pin
> > > (+ few extra)
> > > > > >with very flexible interconnect, while keeping the package pin
>count
> > > > > >reasonable. XAUI is the high bandwidth pipe to get data to and
>from
> > > > > >your big ASIC.
> > > > > >
> > > > > >The other reason for XAUI was to define an interface for the
> > > backplane
> > > > > >and ASIC so they can be developed, while everyone is arguing on the
> > > > > >right PMD for 10 gig.
> > > > > >
> > > > > >Thanks,
> > > > > >
> > > > > >Ali Ghiasi
> > > > > >Sun Microsystems
> > > > > >
> > > > > > >
> > > > > > > Thank you,
> > > > > > > Roy Bynum
> > > > > > >
> > > > > > > At 10:13 PM 7/23/00 -0700, Rich Taborek wrote:
> > > > > > >
> > > > > > > >Roy,
> > > > > > > >
> > > > > > > >As is usually the case, you always bring up interesting
> > > tangential
> > > > > > > >issues in your email. This time it's:
> > > > > > > >
> > > > > > > >"Given the form factor that would use XAUI, SFF connectors
>would
> > > > not be
> > > > > > > >a requirement."
> > > > > > > >
> > > > > > > >What in the world does the XAUI interface, specified for
> > > use as an
> > > > XGMII
> > > > > > > >extender, have to do with SFF connectors???
> > > > > > > >
> > > > > > > >Please enlighten me.
> > > > > > > >
> > > > > > > >Best Regards,
> > > > > > > >Rich
> > > > > > > >
> > > > > > > >--
> > > > > > > >
> > > > > > > >Roy Bynum wrote:
> > > > > > > > >
> > > > > > > > > Chris,
> > > > > > > > >
> > > > > > > > > I am not sure of your comment about LC having a proven track
> > > > record
> > > >for
> > > > > > > > > single mode implementations. At present, WorldCom has not
> > > > deployed
> > > >any
> > > > > > > > > LC. All of the connectors currently specified for SM
> > > > installations is
> > > > > > > > > SC. A particular vendor is attempting to get
> > > WorldCom to make
> > > > use of
> > > > > >their
> > > > > > > > > connectors. ( I will not say how successful or not they
>are.
> > > > > > ) Several
> > > > > > > > > system vendors are attempting to make use of LC, but
> > > at present,
> > > > > > none have
> > > > > > > > > been certified. Given the form factor that would use
> > > XAUI, SFF
> > > > > > connectors
> > > > > > > > > would not be a requirement.
> > > > > > > > >
> > > > > > > > > Thank you,
> > > > > > > > > Roy Bynum
> > > > > > > > >
> > > > > > > > > At 04:28 PM 7/21/00 -0600, Chris Simoneaux wrote:
> > > > > > > > >
> > > > > > > > > >Our opinion is that LC is a better connector than
> > > MTRJ. The LC
> > > > > > does not
> > > > > > > > > >seem to suffer the possible damage that MTRJ can see
> > > with high
> > > > > >mate/demate
> > > > > > > > > >cycles...due to the guide pin action. Also, the LC
> > > has a proven
> > > >track
> > > > > > > > > >record for singlemode whereas the MTRJ does not.
> > > > > > > > > >
> > > > > > > > > >PS: My feeling is the standards body's charter should be to
> > > > specify a
> > > > > > > > > >connector. However, there's too much rhetoric in the
> > > procedure.
> > > > > > Therefore
> > > > > > > > > >it's difficult to choose the best solution.
> > > Inevitably the real
> > > > > > winner/s
> > > > > > > > > >will come forward. Conclusion: Choose a connector at
> > > the standards
> > > > > > > > level as
> > > > > > > > > >it can expose good points of each solution.
> > > > > > > > > >
> > > > > > > > > >Chris Simoneaux
> > > > > > > > > >Picolight
> > > > > > > >
> > > > > > > >-------------------------------------------------------
> > > > > > > >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@xxxxxxxxxxx
> > > > > > > >Santa Clara, CA 95054 http://www.nSerial.com
> > > > > > >
> > > > >
> > >
> > >
>
>--
>Joel Goergen
>Force10 Networks
>1440 McCarthy blvd
>Milpitas, Ca, 95035
>
>Email: joel@xxxxxxxxxxxxxxxxxxx
>Direct: (408) 571-3694
>Cell: (612) 670-5930
>Fax: (408) 571-3550