[Asterisk-Users] Zaptel DACS and FDL

[Jerry]

On Feb 16, 2005, at 7:19 PM, Eric Wieling wrote:

> Jerry wrote:
>
>> On Feb 16, 2005, at 3:07 PM, Eric Wieling wrote:
>>> I have the following configuration:
>>>
>>> CLEC -> T-1 -> Asterisk -> Adtran Channel Bank -> (analog) -> Nortel
>>>
>>> Don't complain that it's ugly.  I've already done plenty of that.
>>>
>>> The CLEC manages their Adtran remotely and needs to be able to 
>>> continue to do so.  I assume they use FDL to do the management.  We 
>>> are using the Zaptel DACS/DACSRBS to cross connect some of the 
>>> channels directly between the CLEC and the Adtran.  These are 
>>> channels we don't really care about (data, other voice, etc).  We 
>>> are not cross connecting all the channels, just some of them.
>>>
>>> I'm wondering if/how I can make sure the remote management via FDL 
>>> continues to work.  Does anyone have any information on this or 
>>> suggestions or anything?
>> What you dropped from your diagram is the T1 from * to the channel 
>> bank. FDL is a link level protocol. It is carried in the framing bits 
>> of the T1 not within the payload bits. When you use the digium (I 
>> presume) card within your * server as a DACS this is connecting the 
>> payload, ie timeslot, bits from one port to another. FDL will not 
>> work this way.
>
> DACSRBS does DACS the robbed bit signalling.  I assume this won't 
> help?   Ah well.  We'll try to find some other way to do

Robbed bit refers to robbing a bit from the payload - hence the name - 
and the reason you can only get a 56k channel on links utilizing this 
form of signalling - vs 64k when not.