RE: Question on the Maximum number of packets per second
with the only problem, that the +/-20ppm capable timing recovery of the
other end will not lock to my +/-100ppm offset data. This is the whole point
of Roy's discussion. We need to resolve this.
Stefan M. Wurster
465 Fairchild Drive, Suite 130
Mountain View, CA 94043
[mailto:owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx]On Behalf Of Sanjeev
Sent: Thursday, May 31, 2001 13:28
To: Joshua J. Brickel; stds-802-3-hssg@xxxxxxxx
Subject: Re: Question on the Maximum number of packets per second
In LAN PHY the remote (transmitter) clock can be 100ppm faster and the local
(receiver) clock can be 100ppm slower than the nominal and be compliant.
results in 0.1024 bits more (for 64byte packets) that would reduce
the ipg by this number resulting in 14.88322 (round to 14.8833) mpps.
In WAN PHY I guess it has been changed to +/-20 ppm clock difference allowed
but if one designed for +/-100ppm clock difference packet throughput it will
+/-20ppm clock difference.
At 10:06 AM 05/31/2001 +0200, Joshua J. Brickel wrote:
>I was wondering if to find for 10GbE the maximum number of packets that
>enter on an interface per unit time can be calculated as follows...
>64bytes for minimum packet + 8 Bytes Preamble/SFD + 12 Bytes IPG/EFD = 84
>bytes = 672 bits
>Then the maximum number of these minimum sized packets would be 10E+10/672
>This would seem correct, except that I have not included how much off the
>transmitters clock can be. Can this significantly alter the numbers I have
>above? If anyone has any insight as to how fast a clock could be off of
>nominal 10 gigabit rate and still be considered compliant I would