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Re: 9.584640


The amount of OC192 that is going into the transport network in the US is
staggering.  The 2 million ports that forecast was for one transport vendor
only.  There are at least four more vendors (not allowed to use names) that have
similar forecasts.  That makes the overall forecast for OC192 ports closer to 10

I work for one of several common carrier service providers that is going to be
deploying a massive amount of OC192 for the next several years.  We are even
deploying OC192 in metro systems.

What should not be a surprise is that the majority ( over 80% ) of the new
traffic on the OC192 systems will be data.  Much of these systems will be OC192C
systems directly from data elements such as routers and other data switches.
This is the market that 10GbE will be competing in.  If it has an encumbrance
because it requires all green field systems, it will not have the impact that
802.3 normally has in spite of the tradition of commodity prices.

Thank you,
Roy Bynum
MCI WorldCom

Hon Wah Chin wrote:

> Perhaps a difficult number to remember, but with the +- 100ppm tolerance
> and a bit rate that needs only to fit within about 200ppm of the nominal
> SONET number we should be able to choose a round number with 4 digits in it.
>   ---
> As I understand the presentations in Montreal on speed,
> a strong advantage of choosing this OC-192 payload rate is
> to transport the signal over SONET OC-192 equipment.  This would
> be from a "10Gb/s Ethernet" port out to SONET gear, which is really
> a PMD external interface rather than a definition for the MAC/PLS interface
> and data rate.
> Given a raw continuous bit stream at the PMD, some scheme for
> framing packets would be needed.  10M used a carrier, 100M used coding,
> 1000M used coding.  Using coding where the PMD speed is fixed at 9.58Gb/s
> would mean a further speed reduction (probably 10-20%) at the MAC/PLS
> interface.
> The discussion at the meeting has already started to consider ways of
> reducing
> the useful throughput at the MAC/PLS below the data clocking rate.  An
> alternative framing scheme presented to HSSG, which has a smaller throughput
> reduction, requires a packet length header -- a departure from previous 802
> practice.
> In considering the advantage of leveraging SONET OC-192 transport
> we should also consider the issues which come up in actually getting
> the hoped-for benefits.  It would also be worthwhile to carefully consider
> what volume forecasts for the OC-192 components can be documented, in
> evaluating the advantage to be gained.  Counting IEEE802.3 10Gb/s data
> ports (however the definition works out) to get 2 million ports sounds
> good, but I found the forecast of 2,000,000 OC-192 ports in 2000 rather
> surprising.
> -hwc