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RE: RS minimum IPG




Sanjeev,

I can't quite parse what you've said. In any case, Shimon has pointed out
where it is specified in 4.4.2. Note that the numbers in 4.4.2 are

   10 Mb/s   47 BT
   100 Mb/s  not specified 
   1 Gb/s    64 BT
   10 Gb/s   40 BT (= 5 Phy characters)

As you can see, consistancy between speeds was not particularly a goal.

Pat

-----Original Message-----
From: Sanjeev Mahalawat [mailto:sanjeev@xxxxxxxxx]
Sent: Tuesday, February 20, 2001 12:45 PM
To: pat_thaler@xxxxxxxxxxx; pat_thaler@xxxxxxxxxxx; sanjeev@xxxxxxxxx;
stds-802-3-hssg@xxxxxxxx; yariv@xxxxxxxxxxxxx
Subject: RE: RS minimum IPG



At 01:10 PM 02/20/2001 -0700, pat_thaler@xxxxxxxxxxx wrote:
>I dashed off my response too quickly. I meant to say "I don't know of
>anyplace a minimum receive IPG of 4 is stated for 10 Gb/s."
>
>Pat

The original question was why everybody is talking about 
shrinking the IPG to 4 bytes. The receive IPG is never shrinked
to 4 bytes and and it is never less than 5 bytes at RS receive
theoritically,
for explained or unexplaned reasons, it is an issue that 
specify the preamble and the min IPG that 
are "consistence" with the slower speeds those are 4 bytes
min IPG and SFD at RS. I am not sure of you chasing the the place.

Thanks
-Sanjeev


>
>-----Original Message-----
>From: pat_thaler@xxxxxxxxxxx [mailto:pat_thaler@xxxxxxxxxxx]
>Sent: Tuesday, February 20, 2001 9:48 AM
>To: sanjeev@xxxxxxxxx; stds-802-3-hssg@xxxxxxxx; yariv@xxxxxxxxxxxxx
>Subject: RE: RS minimum IPG
>
>
>
>Sanjeev,
>
>Where do you find such a definition in the standard? I don't know of
>anyplace a minimum receive IPG of 5 is stated. Further, that is a parameter
>that has varied based on speed so what it was at 100/1000 Mb/s does not
>limit our choice at 10 Gig. 
>
>Regards,
>Pat  
>
>-----Original Message-----
>From: Sanjeev Mahalawat [mailto:sanjeev@xxxxxxxxx]
>Sent: Monday, February 19, 2001 11:25 AM
>To: stds-802-3-hssg@xxxxxxxx; yariv@xxxxxxxxxxxxx
>Subject: Re: RS minimum IPG
>
>
>
>The min IPG varies from 9 bytes to 15 bytes
>based on the packet size and due to clock compensation
>the PHY may delete a column that will lead to min
>IPG of 5 Bytes. So, thoeritically it should not be
>less than 5 bytes but the spec. always defines it
>to be 4 bytes as this was in the 100/1000 mbps
>specs.
>
>Thanks
>-Sanjeev
>