dal vs. pri

[bhelpdesk2005]

hi can someone explain the difference of a DAL to a PRI for me please and how they would be configured differently on a definity. thank you.

 

[jgideon]

I can't speak to definity specifically, but the difference between a DAL and a PRI in most LD carrier's world is 'dedicated access line' vs PRI, so plain T1 vs PRI t1. DAL would normally be wink start dtmf T1's, where PRI will have signitalling channel.

 

[Duaneness]

I have also seen "DAL" used to reference the individual T1 channels. So your PRI-T1 will have a Circuit ID, as well as 23 DAL's assigned to it.

 

[bhelpdesk2005]

i thought that a pri was a T1 though isn't it? so it is just a t1 vs. a dedicated t1(DAL)? on the same thought i thought t1s were dedicated to begin with?

the dals that we have in the pbx uses signalling....is the wink start dtmf a signalling mode or does it replace the signaling? thanks

 

[BHodgins]

the main advantage with PRI is much faster call setup times -- you lose one of the channels (the 24th one) for out of band signaling, but your switch will not need to DTMF tones to/from the central office -- outgoing calls complete in less than 1 second instead of 3-4 seconds

also, with local service, PRI can possibly give you caller name delivery in addition to caller ID (ANI) as long as your phone company supports it (SBC does, not sure about Verizon)

 

[bhelpdesk2005]

wow - really...i didn't know that pri offered faster call setup times than a DAL. I'm in the callcenter world - that may help us out greatly - anyone else in the callcenter business?

 

[jgideon]

There used to be a time when carriers would offer a DAL that wasn't necessarily a T1 (telecom*USA before MCI bought them in the midwest comes to mind). PRI's do usually run on a T1, but a 'plain' T1 usually uses E&M/DTMF/MF signalling, whereas PRI is all 'data cannel' out-of-band, which is what makes it faster. You also dont' need as many tone receivers/senders, etc.