RE: Why not have both?
Ed:
The 9.584640 Gbps rate comes from the payload rate of a SDH VC-4-64c
channel which has 1 column of Path and 63 columns of fixed overhead. The
OC-192c rate is slightly larger at 9.620928 since it does not use the fixed
overheads.
The calculation for these numbers in available in my Montreal presentation.
The data bytes available in a SDH VC-4-64c frame are 16,640 bytes/row by 9
rows. We agree on the Baud rate at 9.953280 Gbps and the SPE rate at
9.621504 Gbps.
Paul
At 04:50 PM 9/15/99 -0400, Edward Chang wrote:
>Paul Bottorff:
>
>Would you mind answer Dae Young Kim's question? The similar question was
>asked before, and I believe, you handled that question.
>
>Thanks,
>
>Ed Chang
>NetWorth Technologies, Inc.
>EChang@xxxxxxxxxxxxxxxx
>
>-----Original Message-----
>From: owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
>[mailto:owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx]On Behalf Of Dae Young KIM
>Sent: Wednesday, September 15, 1999 5:27 AM
>To: Edward Chang
>Cc: rabynum@xxxxxxxxxxx; stds-802-3-hssg@xxxxxxxx
>Subject: Re: Why not have both?
>
>
>
>One question on the number.
>
>According to my calculation, with OC192
>
> - The Gross rate is 9.95328 Gbps
>
> - The SPE rate is 9.621504 Gbps
>
> - The user data rate is 9.510912 Gbps
>
>Where does the number 9.548 come from? We've been talking about the pure
>user
>payload, so I'd pick 9.510 Gpbs Ethernet NRZ rate.
>
>I should be mistaken somewhere. Would you please correct me?
>
>Edward Chang wrote:
>
>> Roy:
>>
>> Thanks for proposing a simple WAN/PHY specification. We can move on from
>> here to generate a complete specification for HSSG.
>>
>> I like the fact that your WAN/PHY is based on OC-192C signaling standard,
>> which is widely implemented in the marketplace - Light SONET.
>>
>> Your proposal, surely, is a simple, bare-bone overhead, which I think will
>> do the job.
>>
>> Nevertheless, if there is any other proposal, we should also discuss it.
>>
>> Also, it is the time to start deal with those issues: 9.548...Gbps NRZ
>> scramble data, data rate conversion scheme (10.000/9.548.Gbps), framing,
>> recovered clock characteristics (should meet SONET jitter-transfer,
>> jitter-tolerance, and jitter-generation? Probably not), clock frequency
>> tolerance (100 ppm?), data jtter characteristics, BER, fault reporting,
>> SERDES, target distance (40 km max?), media......etc.
>
>--
>Dae Young KIM
>http://ccl.chungnam.ac.kr/~dykim/
>
>
>
Paul A. Bottorff, Director Switching Architecture
Enterprise Solutions Technology Center
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@xxxxxxxxxxxxxxxxxx