Re: FW: 664b/66b frame alignment in SONET payload
Hi,
Just to clarify my point which I believe is a different from Erik's and
this issue admittedly is not major. The point I was make about "wrapping"
refers to the wrapping the 66-bit code word within the SPE. Given that the
width of the SPE is 16,640 bytes (133,120 bits), the 66-bit code word is not
a multiple of this size, and the last code word at the end of the row will
be split between this row and the beginning of the next row. What this means
is that an aligner function will be needed to handle this "wrapping". Not a big
deal, only that it may entail a 66 to 1 mux which some might want to avoid at
high speed.
-Wesley Lee
Thomas Dineen wrote:
>
> > Gentlepeople:
> >
> > Maybe I am missing something here but I think this is a non-problem.
> >
> > I envision a series of repeating STS-N frames with their
> > encapsulated
> > SPEs as one continuous repeating structure. In other words, after
> > extracting
> > th ubiquitous Transport and Path Overhead there is no wrap around from one
> > SPE to another! The N+1 th SPE follows the Nth SPE in the same manor that
> > the N+1 th row follows the Nth. This is especially useful when floating
> > SPE mode
> > is used with payload pointers.
> >
> > Inherited A Sonet Problem.
> > (Thomas Dineen)
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