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RE: Ethernet_to_SONET

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> -----Original Message-----
> From:	Tom gandy [SMTP:tgandy@xxxxxxxxxxxxxxxx]
> Sent:	Saturday, December 04, 1999 12:35 PM
> To:	stds-802-3-hssg@xxxxxxxx
> Subject:	Ethernet_to_SONET
> Well I've read Roy Bynum's email and the two WORD documents which were
> linked and downloaded from an ITU FTP site.  Interesting stuff and
> thanks
> for the link.  However, I am confused as I don't see any mention of
> the
> problems of mapping from the plesiochronous clock domains of Ethernet
> (up
> to +/- 100 ppm) into a Synchronous Hierarchy.
> Of course, there are also issues with Inner Packet Gap shrinkage which
> might cause some problems for the newly defined IPG/Preamble frame.
> A long time ago there was an ANSI effort started to map FDDI frames
> into
> SONET.  100BASE-X directly follows from the physical layer aspects of
> Anyway, Raj Jain's "FDDI Handbook" discusses this whole clocking issue
> and
> the necessary adding and subtracting of bits.
> I'm probably missing something here, but as it stands, I'm confused.
> Thanks
> Tom Gandy
> Industrial Catalyst