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RE: Data rate standards vs internal switching standards

Title: RE: Data rate standards vs internal switching standards


From the point of view of a valid, standards-based objection, I'd have to agree.  I don't think there has been a valid, standards-based objection to or reason for a non-modulo 10 MAC data rate.  From a pure standards-based reasoning, there is no way to select between 9.58464 or 10 Gb/s for the MAC/PLS data rate.  That's why other things like history, market trends, manufacturer's desires, etc. come into play.

What I find interesting it that there seems to be a belief that setting the MAC/PLS rate objective to be 10 Gb/s prevents using OC-192 equipment.  This is simply not true.  The GbE standards development had an objective of 1 Gb/s at MAC/PLS interface, but that includes packets and IPGs.  The MAC is capable transmitting and receiving data at an instantaneous data rate of 1 Gb/s, but the true packet data rate (or throughput) is less due to the IPG.  An objective of 10 Gb/s is to say that the interface is capable of transmitting and receiving at an instantaneous data rate of 10 Gb/s, but the throughput is up to the HSSG to decide.

As for the use of OC-192 equipment, nothing is written in stone until it's in the standard, but we have a distance objective of 40 km.  If OC-192 equipment satisfies the objectives of the PAR and 5 criteria, then the standard will be written to ensure correct operation with that equipment.


Brad Booth
Level One Communications, Austin Design Center
(512) 407-2135 office
(512) 589-4438 cellular