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Re: [HSSG] 40G MAC Rate Discussion



Title: RE: [HSSG] 40G MAC Rate Discussion

To be sure:  the passive component industry will support whatever data rates are needed.
We are confident of our current ability to support 10-25G serial links both in copper and fiber. The number and magnitude of MAC rates is something that equipment providers, users and silicon vendors need to get comfortable with.

From my personal standpoint, I would tend to conclude that the need for a 100G standard is a given and it needs to include some copper links within a data center. There also appears to be a short term need for 40G, but whether it can sufficiently be addressed with LAG or a separate MAC rate should be defined is something we still need to finalize. Is this a fair observation?

Gourgen


 -----Original Message-----
From:   McGrath, Jim
Sent:   Sunday, April 08, 2007 08:51 PM Central Standard Time
To:     Oganessyan, Gourgen; STDS-802-3-HSSG@listserv.ieee.org
Subject:        RE: [HSSG] 40G MAC Rate Discussion

Just trying to point out something that hasn't been clearly pointed out. There is a constant need for breakout cables in both copper and fiber especially when technologies are first introduced. It's not just what's next, it's also how do you get there.


Jim McGrath
Molex
2222 Wellington Ct
Lisle, IL 60532
Phone: 630-527-4037
Mobile: 630-244-3872
Fax: 630-969-1352




________________________________

From: Oganessyan, Gourgen [mailto:Gourgen.Oganessyan@MOLEX.COM]
Sent: Thursday, April 05, 2007 4:50 PM
To: STDS-802-3-HSSG@listserv.ieee.org
Subject: Re: [HSSG] 40G MAC Rate Discussion


I tend to agree with Joel. I don't think it's fair to demand that the current configurations of passive hardware determine the target MAC data rate. The most viable solution for 100G seems to be 4 lambda, with a smaller possibility of 5 lambda, and 30G serial links will be a lot harder to achieve electrically than 25G.

Gourgen


________________________________

From: Joel Goergen [mailto:joel@force10networks.com]
Sent: Thursday, April 05, 2007 3:38 PM
To: STDS-802-3-HSSG@listserv.ieee.org
Subject: Re: [HSSG] 40G MAC Rate Discussion


Jim,

Please look at past data regarding optic feasibility for 10km solution space.  The optics vendors are suggesting 4by25+FEC as a good fit.  I'm pretty uncomfortable pushing that to 4by30+FEC.

-joel

McGrath, Jim wrote:


        Joel, maybe the 100Gbs target should be 120Gbs. Ribbon fiber cables and the connectors are x12. Assuming a 10Gbs per channel implementation, this works our very nicely. Many copper cables and connectors are also already established at x12. Then the 120Gbs interface could be broken out into 3 40Gbs interfaces or 12 10Gbs interfaces without loosing bandwidth.
        

        Jim McGrath
        Molex
        2222 Wellington Ct
        Lisle, IL 60532
        Phone: 630-527-4037
        Mobile: 630-244-3872
        Fax: 630-969-1352


        

________________________________

        From: Joel Goergen [mailto:joel@force10networks.com]
        Sent: Thursday, April 05, 2007 2:07 PM
        To: STDS-802-3-HSSG@listserv.ieee.org
        Subject: Re: [HSSG] 40G MAC Rate Discussion
       
       
        Ali,
       
        If the front end is defined as 100Gbps, expecting the back end to be 40Gbps makes no sense from system implementation.  Maybe if it were 50Gbps, the TM might be easier to implement.  But either way, you would throw away a lot of bandwidth for a 100 going into 40.
       
        Also, if the front end moves towards 4by25+FEC, which it appears to be based on the work so far, from a system perspective, you would use the same data rate on the back end side with perhaps different signaling.  Further, spending another three years on a 40Gbps back plane standard for such a small gain doesn't seem right.  It was pretty painful the last time around.  You would end up defining 1by40Gbps, 4by10Gbps, 16by3.125Gbps.  I just don't see the ROI.
       
        No one has yet to prove that 4by10Gbps LAG doesn't fit the server market described by Shimon.  And actually, I still don't see the market he is talking about.  Regardless of using LAG on the front end or in an ATCA chassis with multiple LAG connections ... a solution exists today that works well.
       
        Last is someone still has to design an aggregation box to connect all the 40Gs together and pipe them out 100Gs.  I "know the art", and it is very costly to do this.  But that isn't the problem for me ... we can all burn the money to supply a market we've seen no data for or a description of ... the real problem for the systems vendor is we finish the box in 2010 and we have the exact same data performance problem we have today jamming 1G and 10G links into a 10G core.
       
        I propose that rather then do 40G, we put that effort into working with 802.1 to resolve the perceived problems with LAG.  Thus when 100Gbps is complete, we will have a N-LAG ... or New LAG ... that allows the end user to create ANY size pipe required for 1G, 10G, and 100G core or ag implementations.
       
        -joel
       
       
       
        Ali Ghiasi wrote:
       

                Marcus and Others
               
                I like to present another point of view in support of 40 Gig MAC.
                We currently have the following option on the backplane side
                    - KX-4 (XAUI) 10Gig
                    - KR (1 lane ) 10Gig
                The natural next step for backplane Ethernet will be to operate KX-4
                lanes at 10.3125 Gbaud.
                Regardless of what decision we make in the HSSG 40Gig MAC will exist for
                the backplane.
               
                Assuming we will define the 40Gig MAC sooner or later then allowing 40
                Gig MAC
                for front panel becomes even more compelling, specially when 100Gig is
                overkill for these
                applications in near term.  If we define 40Gig MAC in the HSSG then
                defining 40Gig
                backplane becomes travail.
               
                applications.
               
                Thanks,
                Ali
               
               
               
               
                Marcus Duelk wrote:
                > Hi,
                >
                > I think it was common sense at the last meeting that the
                > rate that service providers and IXPs are looking for is 100 GbE.
                > The discussion about 40 GbE is for the *server market*, the
                > classical LAN application of Ethernet. In the network space you
                > have already OTU3 and OC-768c PoS, so there is not much
                > need for another 40G Ethernet interface.
                >
                > Also, my personal opinion is regarding "broad market potential"
                > that there will be more networks or network types that require
                > 100 GbE, however in terms of volumes I could imagine that a 40GbE
                > interface for servers will actually produce more volumes, even though
                > it is only one type of network.
                >
                > Marcus
                >
                >
                > Toshinori Ishii wrote:
                >> Hello,
                >>
                >> I'm another IXP network engineer.
                >>
                >> 2007/4/5, Henk Steenman <henk.steenman@ams-ix.net> <mailto:henk.steenman@ams-ix.net> :
                >>> Back to 40GE: scaling link aggregation using 10GE for another 3 years
                >>> will be very hard. The use of 40GE might be of help here if it would
                >>> allow for standardized products to become available say second half
                >>> of 2008.
                >>> QUESTION: Is there a way to expedite the standardization process (and
                >>> subsequent product development) of a 40GE standard? Within or outside
                >>> of the IEEE?
                >>>
                >>> If the answer to the above is "no" then I would say lets not spend any
                >>> time on anything other than 100GE so no delay is introduced in the
                >>> development of this standard and get it finished as soon as possible.
                >>
                >> Agree.
                >> I need 100GE ASAP.
                >>
                >
               
               

                ________________________________


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                adr;dom:;;3151 Zanker Road;San Jose;CA;95014
                email;internet:aghiasi@broadcom.com
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                tel;cell:(949)290-8103
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