Re: STS Pointer question
Norival,
I've done a bit more research on this topic and I think
I've answered my own questions.
First, I was confused by the description of "first H1/H2".
Apparently what this means is that the first octet of the
192 H1 octets in each SONET frame is coded as 0x62 and all
other octets in the SONET frame are coded as ox93. For
some reason, I was originally reading this as all H1 octets
in the first SONET frame were coded as 0x62 while all H1
octets in all subsequent SONET frames are coded as 0x93.
This "breakthrough" made everything else pretty much fall
into place. Sorry for the confusion.
Ben
"Brown, Ben [BAY:NHBED:DS48]" wrote:
>
> Norival,
>
> In the WIS Update presentation made earlier this month, the
> "Payload Pointer" octets (H1 & H2) contain one value for the
> very first SONET frame and another value for all other SONET
> frames. The first value appears to be a "New Data Flag" and
> provides an absolute pointer to the start of the next SPE.
> The other values have the New Data field in "normal mode"
> and provide no offset.
>
> If the first SONET frame is lost due to the synchronization
> process, how does the receive WIS's payload pointer processor
> logic know what to use as a starting pointer? The transmit
> WIS will never send another. Does the receive WIS use 522 as
> a default? What if a pointer adjustment was made because of
> multiple SONET repeaters in the link but lost due to a multi-
> frame synchronization process? Should the transmit WIS send
> a "New Data Flag" once synchronization is complete? Does the
> transmit WIS know when the receive WIS has gaineed sync?
>
> If this is described somewhere in you presentations, please
> let me know.
>
> Thanks,
> Ben
>
> --
> -----------------------------------------
> Benjamin Brown
> Router Products Division
> Nortel Networks
> 1 Bedford Farms,
> Kilton Road
> Bedford, NH 03110
> 603-629-3027 - Work
> 603-624-4382 - Fax
> 603-798-4115 - Home
> bebrown@xxxxxxxxxxxxxxxxxx
> -----------------------------------------
--
-----------------------------------------
Benjamin Brown
Router Products Division
Nortel Networks
1 Bedford Farms,
Kilton Road
Bedford, NH 03110
603-629-3027 - Work
603-624-4382 - Fax
603-798-4115 - Home
bebrown@xxxxxxxxxxxxxxxxxx
-----------------------------------------