Can anyone, pls. explain to me what is actually the relationship based on the functionality of FXS, DID or FXS/DID, FXO, PRI-T1 ?
Are the DID Trunks similar to the trunks of PRI-T1, say 24 channles ? Are these 23 b-channels and 1 d-channel for a PRI-T1 are the same as trunks of the DID service?
Dou you still need a DID service offered by telephone companies that enables callers to dial directly an extension on a PBX or packet voice system if you have already a PRI-T1 service?
Do they have the same function between DID Trunks and Voice Channels of PRI T1?