[asterisk-biz] PRI confusion

[emist]

Hey guys,

I was hoping someone could clarify this for me since i've been trying to
find out for a while now to no avail. Im thinking of deploying a call
routing service through asterisk. Basically I want people to be able to
call a number through the PSTN and then call whatever extension to be
routed through a voip termination provider.

Im guessing using a PRI is the best way to do this. However, im confused
as to how it all works. Say a PRI has 23 usable channels, does that mean
that I will be able to route 23 calls at the same time or does it mean
that I would have to split 11 channels for incoming voice traffic(from
PSTN) and 11 channels for outgoing voip traffic?

Im stomped =\