Re: Issues concerning 10GbE speed standards
- To: Ed Grivna <elg@cypress.com>, BRIAN_LEMOFF@hp-paloalto-om16.om.hp.com, Bruce_Tolley@3com.com
- Subject: Re: Issues concerning 10GbE speed standards
- From: Colin Mick--The Mick Group <ckm@mickgroup.com>
- Date: Mon, 28 Jun 1999 16:28:55 -0700
- Cc: BRIAN_LEMOFF@hp-paloalto-om16.om.hp.com, nuss@lucent.com, drew.perkins@lightera.com, pbottorf@nortelnetworks.com, Peter_Wang@3com.com, rabynum@airmail.net, stds-802-3-hssg@ieee.org
- In-Reply-To: <199906282233.RAA01305@geronimo.cypress.com>
- Sender: owner-stds-802-3-hssg@majordomo.ieee.org
Ed--
I agree 100%.
Consensus building is part of the standards process.
The give and take of the process results in a much stronger solution.
It's far too soon to be making any decisions; let's develop some critera to
evaluate solutions and then get the solution providers (of which there seem
to be many)
provide information in a common format so the solutions can be compared.
Colin
At 05:33 PM 6/28/99 -0500, Ed Grivna wrote:
>Colin,
>
>I agree that decisions need to be made, but they need to be made
>in the proper venue, not one person voicing an opinion as fact, that
>has yet to reach any volume agreement among the members or players.
>
>There are significant developments being made in the encoding,
>modulation, transmission, reception, etc. areas of technology
>that have yet to see the light of day within the development
>of this committee. A number of these proposals have requested
>agenda time for the next meeting. I think it behooves all
>participants to keep an open mind with respect to the development
>taking place here.
>
>Unfortuantely I see far too little of that. What I do see is
>people with minds made up before they've even seen the proposals.
>
>Thats not what is supposed to be happening. The jury should
>definately still be out on this, though I do agree that deliberations
>are quite appropriate at this time.
>
>Cool heads allowed multiple proposals to converge in the 802.3ab
>development. I would hope that similar cooperation can take place
>here.
>
>The message sent out earlier today by Mr. Nuss was quite out of order.
>He also made a very strong attempt to state this his opinions were
>in reality fact. Fortunately others saw through this smoke screen.
>Is scrambling proper for the LAN? I don't know. Until all proposals
>have been heard and evaluated, that, and that alone, is the only
>VALID reponse to any of these proposals.
>
>Regards,
>
>Ed Grivna
>Cypress Semiconductor
>
>
>Colin Mick wrote:
>>
>> I think multiuple competing solutions and a "let the market decide" is a
>> sure recipe for disaster.
>> It guarantees inoperable solutions and promotes market confusion.
>>
>> Making decisions among competing techincal solutions is a tough but
>> necessary part of the standards process.
>>
>> Colin
>>
>> At 01:42 PM 6/28/99 -0700, BRIAN_LEMOFF@HP-PaloAlto-om16.om.hp.com wrote:
>> >
>> > Bruce,
>> >
>> > We have not yet had any such presentations. It will be difficult to
>> > get an accurate picture since products are not yet available, and
each
>> > PMD advocate believes his/her approach to be the lowest cost. Ed
>> > Chang wants to let the market decide, and that might not be a bad
>> > idea. I think the best we can do is to continue to present
results as
>> > they become available. Efforts to exclude an approach from the
>> > standard due to cost, before any products are available, and before
>> > reliable cost information is available could be very dangerous,
unless
>> > there is widespread agreement on relative cost, time-to-market, and
>> > probability of success.
>> >
>> > -Brian Lemoff
>> > HP Labs
>> >
>> >
>> >
>> >______________________________ Reply Separator
>> _________________________________
>> >Subject: Re: Issues concerning 10GbE speed standards
>> >Author: Non-HP-Bruce-Tolley (Bruce_Tolley@3com.com) at
HP-PaloAlto,mimegw2
>> >Date: 6/28/99 10:42 AM
>> >
>> >
>> >
>> >
>> >
>> >Have we seen any formal detailed presentations on the relative costs of
>> any of
>> >the proposals???
>> >
>> >
>> >Bruce Tolley
>> >3Com Corp
>> >
>> >
>> >
>> >
>> >BRIAN_LEMOFF@HP-PaloAlto-om16.om.hp.com on 06/28/99 10:17:37 AM
>> >
>> >Sent by: BRIAN_LEMOFF@HP-PaloAlto-om16.om.hp.com
>> >
>> >
>> >To: nuss@lucent.com
>> >cc: drew.perkins@lightera.com, pbottorf@nortelnetworks.com, Peter
>> > Wang/HQ/3Com, rabynum@airmail.net, stds-802-3-hssg@ieee.org (Bruce
>> > Tolley/HQ/3Com)
>> >Subject: Re: Issues concerning 10GbE speed standards
>> >
>> >
>> >
>> >
>> >
>> > Martin,
>> >
>> > Your claim that "... a serial 10-Gig solution is definitely going to
>> > be the cheapest one by the time 10G Ethernet sales seriously take
off"
>> > is absolutely outrageous, and has no place on this reflector.
Perhaps,
>> > relative to other solutions that Lucent has been able to develop,
>> this is
>> > true, but there have been several other proposals (including the HP
>> WWDM,
>> > Blaze WWDM, Transcendata MAS) that could very well be cheaper than
>> serial
>> > 10-Gig for MANY YEARS TO COME.
>> >
>> > Your argument in favor of scrambling is valid, but it also has to be
>> > balanced against the disadvantage of designing electronics that
support
>> > very low frequencies. AC balanced electronics (both TX and RX) with
>> > relatively high low frequency cutoffs tend to have less jitter and
>> result
>> > in higher sensitivity. In the regime that we are working on (i.e.
our
>> > low-cost 4 channel WWDM module) the trade-off between 2.5-Gbaud
>> scrambled
>> > and 3.125-Gbaud 8B/10B is a close call. There are pros and cons
to both
>> > sides. Certainly both are well within the realm of low-cost
electronic
>> > processes.
>> >
>> > -Brian Lemoff
>> > HP Labs
>> >
>> > ______________________________ Reply Separator
>> > _________________________________
>> > Subject: Re: Issues concerning 10GbE speed standards
>> >Author: Non-HP-nuss (nuss@lucent.com) at HP-PaloAlto,mimegw2
>> >Date: 6/28/99 8:20 AM
>> >
>> >
>> >All,
>> >
>> >I think we are making a mistake by talking about scrambling in the WAN
>> >and 8B/10B in the LAN. There are a lot of good reasons why we need to
>> >look at scrambling in the LAN as well:
>> >
>> >1) a serial 10-Gig solution is definitely going to be the cheapest one
>> >by the time 10G Ethernet sales seriously take off. That is true in the
>> >LAN as well. You do not want to exclude an option that promises to be
>> >the cheapest one!
>> >
>> >2) there is no significant cost advantage in 8B/10B coding over
>> >scrambling from an optics and electronics point of view
>> >
>> >3) there is however a cost penalty going to higher speed optics and
>> >electronics. 10 Gb/s can be achieved rather readily for both optics and
>> >electronics, but a 25% overhead likely makes things more expensive
>> >
>> >4) the lower line rate (10.00 vs. 12.5 Gb/s) directly translates into
>> >longer distances supported, more power budget, and less penalties (such
>> >as DMD).
>> >
>> >
>> >Martin Nuss
>> >
>> >
>> >
>> >Drew Perkins wrote:
>> >>
>> >> Paul,
>> >> You hit on another very good reason for the WAN version to use
>> >> scrambled encoding. Let me rephrase it for emphasis. I believe it is a
>> >> requirement that 10 Gb/s Ethernet be able to ride over existing DWDM
spans.
>> >> These spans have already been engineered for 10 Gb/s channels.
Increasing
>> >> the bit rate would increase the optical bandwidth, and would require
>> >> increasing the optical power as well. Thus an 8B/10B 12.5 Gb/s signal
would
>> >> not be able to ride on most existing spans, but would instead require
>> >> completely new spans to be engineered. This will not be acceptable to
many
>> >> carriers. Therefore, using scrambling is clearly a hard requirement
for 10
>> >> Gb/s Ethernet over DWDM systems.
>> >>
>> >> This is, of course, not a factor in the decision whether to use
8B/10B or
>> >> scrambling in the LAN.
>> >>
>> >> Drew
>> >> ---------------------------------------------------------
>> >> Ciena Corporation Email: ddp@lightera.com
>> >> Core Switching Division Tel: 408-865-6202
>> >> 10201 Bubb Road Fax: 408-865-6291
>> >> Cupertino, CA 95014 Cell/Pager: 408-829-8298
>> >>
>> >> -----Original Message-----
>> >> From: owner-stds-802-3-hssg@majordomo.ieee.org
>> >> [mailto:owner-stds-802-3-hssg@majordomo.ieee.org]On Behalf Of Paul
>> >> Bottorff
>> >> Sent: Saturday, June 26, 1999 9:20 AM
>> >> To: Drew Perkins; 'Peter_Wang@3com.com'; 'rabynum@airmail.net'
>> >> Cc: 'stds-802-3-hssg@ieee.org'
>> >> Subject: RE: Issues concerning 10GbE speed standards
>> >>
>> >> Drew:
>> >>
>> >> The data I've seen agrees exactly with your outlook that the total
system
>> >> cost is considerably higher using 12.5 Gig rather than 10 Gig. In
addition,
>> >> the installed base of transmission systems, which has many available
>> >> lambda, is definitely 10 Gig. The 12.5 Gig solutions can only be used in
>> >> for new installations.
>> >>
>> >> Our current research indicates that the scrambled encoders do not
increase
>> >> the cost of components versus 8b/10b when used for the same application.
>> >> Infact, we believe scramblers are less costly than 8b/10b due to the
lower
>> >> frequencies. The current analysis of 8b/10b considers the effects of
jitter
>> >> compared to the worst case conditions for scrambled coding. This
analysis
>> >> does not give an accurate picture of the requirements for scrambled
>> >> encoding since the probability of the imbalance used in the
comparison is
>> >> once in more than 10,000 years. Scramblers are statically DC
balanced, it
>> >> is necessary to look at the requirements statistically rather than in
the
>> >> worst case.
>> >>
>> >> Paul
>> >>
>> >> At 10:21 PM 6/25/99 -0700, Drew Perkins wrote:
>> >> >
>> >> >Peter and Roy,
>> >> > The cost of higher speed in the WAN is not so much that of the
>> >> >electronic parts, but rather the fact that you need more of them for
long
>> >> >distances. This is because most optical effects such as dispersion
>> increase
>> >> >with the square of the distance. Thus increasing the speed by 25%
>> increases
>> >> >the optical effects by 56%, and that tends to decrease the distance you
>> can
>> >> >go by about a third. Then you need 33% more spans to go the same
>> distance.
>> >> >Also, in order to send 25% more bits, you wind up increasing the
power by
>> >> >25%, and you use more optical bandwidth. And since you are sending more
>> >> >bits, you are using more optical bandwidth. These facts result in fewer
>> >> >optical channels being supportable on a fiber, resulting in more fibers
>> >> >being used, resulting in more line systems, etc. The result again
is more
>> >> >equipment and higher costs.
>> >> >
>> >> >Actually, the electronic parts might become less expensive with the 25%
>> >> >extra speed. The balanced nature of the 8B10B code decreases the
cost and
>> >> >attention that must be paid to jitter.
>> >> >
>> >> >Drew
>> >> >---------------------------------------------------------
>> >> >Ciena Corporation Email: ddp@lightera.com
>> >> >Core Switching Division Tel: 408-865-6202
>> >> >10201 Bubb Road Fax: 408-865-6291
>> >> >Cupertino, CA 95014 Cell/Pager: 408-829-8298
>> >> >
>> >> >
>> >> >-----Original Message-----
>> >> >From: owner-stds-802-3-hssg@majordomo.ieee.org
>> >> >[mailto:owner-stds-802-3-hssg@majordomo.ieee.org]On Behalf Of
>> >> >Peter_Wang@3com.com
>> >> >Sent: Friday, June 25, 1999 8:35 PM
>> >> >To: rabynum@airmail.net
>> >> >Cc: stds-802-3-hssg@ieee.org
>> >> >Subject: Re: Issues concerning 10GbE speed standards
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >Roy,
>> >> >
>> >> >>From a number of the component vendors' presentations at CFI, I don't
>> >> recall
>> >> >anyone claiming that the cost of the electronic parts (SiGe or GaAs)
will
>> >> be
>> >> >much different between 10 & 12.5 Gbps. The primary cost issue
seemed that
>> >> >of
>> >> >the relative laser performance (e.g. temperature stablization).
Also, if
>> >> >you
>> >> >are talking about "converting" an existing Sonet chip to silicon
(meaning
>> >> >that
>> >> >the existing desing is in GaAs) and throwing away a bunch of
circuits, I
>> >> >wouldn't be so sure that the development cost would be much less.
In any
>> >> >case,
>> >> >assuming the volume is large (which I'm sure everyone's hoping), the
>> >> >development
>> >> >cost will be amortized, and hence not a significant factor. But
this is a
>> >> >discussion for LAN (or enterprise) applications. I was trying to
>> >> understand
>> >> >the
>> >> >economics of applying Ethernet to WAN but forcing it within the
existing
>> >> WAN
>> >> >practice, and hoping you could provide some insight.
>> >> >
>> >> >Peter
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >Roy Bynum <rabynum@airmail.net> on 06/25/99 04:50:23 PM
>> >> >
>> >> >Please respond to rabynum@airmail.net
>> >> >
>> >> >Sent by: Roy Bynum <rabynum@airmail.net>
>> >> >
>> >> >
>> >> >To: Peter Wang/HQ/3Com
>> >> >cc: stds-802-3-hssg@ieee.org
>> >> >Subject: Re: Issues concerning 10GbE speed standards
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >Peter,
>> >> >
>> >> >Just because a SONET OC192C framing is used, does not mean that the
OAMP
>> >> >functionality is active in the LAN interface. If OAMP processing is
not
>> >> >needed, only the existing SONET chip set, converted to silicon, with
>> >> >most active functionality, other than path BER can be disabled. This
>> >> >will leverage the existing technology without the higher cost of the
>> >> >APS, line and section overhead, etc.
>> >> >
>> >> >Having worked on devices before, I know that the higher the bit signal
>> >> >rate the more expensive the devices. With a PHY that is 1/4 higher in
>> >> >bit rate, compared the 8B/10B signal rate, the OC192 rate may be less
>> >> >expensive.
>> >> >
>> >> >Roy
>> >> >
>> >> >
>> >> >
>> >> >Peter_Wang@3com.com wrote:
>> >> >>
>> >> >> It will help a great deal if you could point out specific aspects and
>> >> >approaches
>> >> >> where an Ethernet extended to support all of the existing common
carrier
>> >> >O&M
>> >> >> requirements, encapsulated within the existing Sonet/SDH structure,
>> >> >running
>> >> >over
>> >> >> existing OC192/STM64 facilities, will actually come out costing
>> >> >significantly
>> >> >> less that the current solution?
>> >> >> - Peter
>> >> >>
>> >> >> Roy Bynum <rabynum@airmail.net> on 06/20/99 07:34:08 AM
>> >> >>
>> >> >> Please respond to rabynum@airmail.net
>> >> >>
>> >> >> Sent by: Roy Bynum <rabynum@airmail.net>
>> >> >>
>> >> >> To: wthirion@level1.com
>> >> >> cc: stds-802-3-hssg@ieee.org, stds-802-3-hssg-speed@ieee.org (Peter
>> >> >> Wang/HQ/3Com)
>> >> >> Subject: Issues concerning 10GbE speed standards
>> >> >>
>> >> >> Walt, et al,
>> >> >>
>> >> >> The issue of speed is one of economics. The existing GbE standard
does
>> >> >> not allow for any operations support for the optical fiber facility.
>> >> >> This makes GbE very expensive to maintain and support over a MAN/WAN
>> >> >> environment. The cost of ownership of GbE will prevent it from
having a
>> >> >> masive impact directly on the cost of MAN and WAN data
communications.
>> >> >>
>> >> >> Common carrier protocols, such as DS1/DS3/SONET/SDH have
operations and
>> >> >> maintencance functionality incorporated in the overhead of the
>> >> >> protocol. DS1 and DS3 have a subcarrier that provides remote and
>> >> >> reverse signalling outside of the transport "payload". This allows
>> >> >> carriers to troubleshoot and maintain remote systems without
haveing to
>> >> >> dispatch someone for every little issue. In some respects, GbE
fails to
>> >> >> meet the 802.3 functional requirements for interoperation with common
>> >> >> carrier systems.
>> >> >>
>> >> >> 1000BaseSX and 1000BaseLX are optical networking standards. Whether
>> >> >> this was the intention or even the perception of the 802.3 working
>> >> >> group. The working group did not include any support for
operations or
>> >> >> maintenance in the optical domain for this protocol. The functional
>> >> >> operations of copper LAN facilities are well understood by the 802.3
>> >> >> working group, but when you get beyond multi-mode, 850nm, optical
>> >> >> transport, it is no longer a LAN, it is a WAN. Some will say that
30km
>> >> >> is a MAN, not a WAN. If you apply the same function processes
>> >> >> distictions to optical systems that are applied to copper systems,
you
>> >> >> will discover that a MAN is actually a WAN within a single central
>> >> >> office domain. When I was actively working on Ethernet, when it
left the
>> >> >> building, it was no longer a LAN, it was a WAN.
>> >> >>
>> >> >> In order for 10000BaseX to support MAN/WAN systems within common
carrier
>> >> >> facilities, common carrier operations and maintance support must be
>> >> >> within the protocol. SONET/SDH are the current, and most widely
>> >> >> deployed transport protocols within the common carrier domain.
>> >> >> SONET/SDH use the transport overhead to provide that functionality.
>> >> >> That functionality allows the common carriers to reduce the
operations
>> >> >> and support costs for the fiber optic transport systems, and thus
lower
>> >> >> the overall costs passed on to the end users. This will be the
economic
>> >> >> breaking point for 10GbE. Can it directly support the fiber optic
>> >> >> transmission system? Is there any reason why it should not be
able to
>> >> >> directly provide operations support for the optical fiber systems?
>> >> >>
>> >> >> A second economic issue of speed for 10GbE is one of utilizing
existing
>> >> >> technology and standards at the ~10Gigabit speed range. A masive
>> >> >> install base of facilities and support already exist for
OC192/STM64 on
>> >> >> a global scale. Optical amplifers, signal and clock recovery
>> >> >> regenerators, and other systems are already in place to carry
>> >> >> OC192/STM64 signals in metropolitan as well as wide are networks. I
>> >> >> would not want to contemplate the economic impact of having to
install
>> >> >> totally seperate technology to support 10GbE. If it can not use the
>> >> >> existing ~10Gb technology and facilities, Other than "dark fiber",
10GbE
>> >> >> will have to be installed over a totaly new, and totaly seperate
>> >> >> facilities. Is there any reason why 10GbE should not support and
make
>> >> >> use of the existing ~10Gb transport facilities?
>> >> >>
>> >> >> I hope that this message has not been too long. As an employee of a
>> >> >> common carrier company, I have a recognizable vested interest in
looking
>> >> >> toward 10GbE as a major economical alternative to existing data
tranport
>> >> >> technolgy, such as TDM or ATM. I have almost 20 years of designing,
>> >> >> installing, and supporting LAN, MAN, and WAN systems. I have seen
the
>> >> >> economics change as more self-supporting protocols and
technologies have
>> >> >> become available. The key is to provide a protocol that allows
remote
>> >> >> operations support, which reduces the number of "warm bodies" that
are
>> >> >> required to support the systems. This is what I am asking for. Is
>> >> >> there any reason why this can not be done?
>> >> >>
>> >> >> Thank you,
>> >> >> Roy Bynum
>> >> >> MCI WorldCom
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >
>> >> Paul A. Bottorff, Director Switching Architecture
>> >> Bay Architecture Laboratory
>> >> Nortel Networks, Inc.
>> >> 4401 Great America Parkway
>> >> Santa Clara, CA 95052-8185
>> >> Tel: 408 495 3365 Fax: 408 495 1299 ESN: 265 3365
>> >> email: pbottorf@NortelNetworks.com
>> >
>> Colin K. Mick
>> The Mick Group
>> 2130 Hanover St,
>> Palo Alto, CA 94306
>> voice: (650) 856-3666
>> FAX: (650) 494-3737
>> email: ckm@mickgroup.com
>> URL: www.mickgroup.com
>
Colin K. Mick
The Mick Group
2130 Hanover St,
Palo Alto, CA 94306
voice: (650) 856-3666
FAX: (650) 494-3737
email: ckm@mickgroup.com
URL: www.mickgroup.com