j0 byte in sdh rsoh

[Suchitra]

1. reference - 9.2.2.2 from g.707
----------------------------------
i want to know when exactly is the 16 byte frame which is defined
for section access point identifier transferres and how is it
distinguished from other frames?

2.reference figure 6-1 from g.707.
---------------------------------
during demultiplexing of AUG1 how do we know that it is formed
from c3--VC3--TU3--TUG3--VC4--AU4
or from
c3--VC3--AU3--AUG1

is the c2 byte(signal lable in POH)that decides it.
3. reference 8.1.1
------------------
How to understand that the 4th row of an STM - 1 frame carries a
single AU - 4 pointer or three AU -3 pointers.

[Pushkar Naik]

Hii Suchitra,

Look for ### as my response.

such...@einfochips.com (Suchitra) wrote in message news:<8f80f646.02062...@posting.google.com>...

> 1. reference - 9.2.2.2 from g.707
> ----------------------------------
> i want to know when exactly is the 16 byte frame which is defined
> for section access point identifier transferres and how is it
> distinguished from other frames?
>

### Every STM-1 frame will have 1 J0 byte (the other 2 bytes per STM-1
reserved for national use). When 16 such STM-1 frames are transmitted,
the receiver collects 1 byte of J0 from each of these 16 STM-1s
received to form a 16-byte section access point identifier, a kind of
trace message frame.
This is a continious process, thus right from power-on till the device
is powered, these 16-byte frames will be transmitted every 16 STM-1's.

> 2.reference figure 6-1 from g.707.
> ---------------------------------
> during demultiplexing of AUG1 how do we know that it is formed
> from c3--VC3--TU3--TUG3--VC4--AU4
> or from
> c3--VC3--AU3--AUG1
>
> is the c2 byte(signal lable in POH)that decides it.

### SONET / SDH are provisioning based technologies, so as per user
provosioning, which the device will know from its configuration
registers, the demultiplexing will take place from
c3--VC3--TU3--TUG3--VC4--AU4 or
c3--VC3--AU3--AUG1

> 3. reference 8.1.1
> ------------------
> How to understand that the 4th row of an STM - 1 frame carries a
> single AU - 4 pointer or three AU -3 pointers.

### Again, SONET / SDH are provisioning based technologies, so as per
user provosioning, which the device will know from its configuration
registers, either 1 AU4 pointer or 3 AU3 pointers will be applied by
the device to the SPE.

Hope this helps.
Regards,
Pushkar.