Re: B3 question
Ben,
Yes, the value of 522 in the 1st SPE pointer points to the beginning
of the next WIS frame envelope capacity, and yes, there will
be no valid data in the envelope capacity of the first WIS frame.
Erik
In message "B3 question", bebrown@xxxxxxxxxxxxxxx writes:
>Erik,
>
>"Trounce, Erik [CRK:5S21:EXCH]" wrote:
>>
>> Hi Ben,
>>
>> The B3 octet covers the previous SPE. Also note that the SPE
>> includes the path overhead, the fixed stuff, and the payload.
>> The SPE from the transmitter is fixed to start after the
>> last Z0 octet in the 1st row, 577th column, of the next SONET frame.
>
>Is that what the 522 means in the first payload pointer? The
>first SONET frame delivered to the medium contains an SPE with
>invalid payload data and the first SPE which actually contains
>valid payload data starts at the beginning of the payload space
>in the next SONET frame.
>
>>
>> So for the transmit case, the B3 octet located in the 2nd row,
>> 577th column of WIS frame #N+1 covers the SPE which is entirely
>> in the envelope capacity (all octets in columns 577 to 17280,
>> rows 1 to 9) of WIS frame #N.
>
>That makes sense now.
>
>Thanks,
>Ben
>
>>
>> Cheers,
>> Erik
>>
>> In message "B3 question", bebrown@xxxxxxxxxxxxxxx writes:
>> >Hi,
>> >
>> >B3 is in the path overhead column of the 2nd row in the WIS frame.
>> >It is specified to cover the most recent SPE. However, the SPE from
>> >the transmitter starts after the "fixed stuff" in the 4th row and
>> >runs to the end of the next 3rd row.
>> >
>> >Does this mean that the B3 octet in WIS frame #N covers the SPE
>> >that starts in WIS frame N-2 and ends in WIS frame N-1?
>> >
>> >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
>-----------------------------------------
>