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Re: 664b/66b frame alignment in SONET payload




Erik,

Even for a (serial ) LAN-phy, the interface to the optics will likely be
in octet boundaries:
(pg.4 in
http://grouper.ieee.org/groups/802/3/ae/public/may00/robinson_1_0500.pdf
)
So the 64/66 codec will anyway need to have a mechanism to extract the
66bit frame from
this octet interface - with potentially 66 valid sync locations. So I
dont see why you need to
constrain the location of the PCS frames within the SONET frame.

regards,
Birdy

--------------------------------------------------------------------
Hi,

I have a question regarding alignment of the PCS 66-bit frames
within the SONET payload (in WAN mode obviously).  My understanding
is that the PCS 66-bit frames can and will cross SONET frames, and
obviously they will not begin on octet boundaries.  However, will
it be specified that the PCS frames will sit on even-bit boundaries,
reducing the valid sync locations from 66 to 33?

Erik