please someone give me a clear answer on this subject cause i asked too many people and each gives me an answer .
i have 2 sites .first site has around 120 analogue and digital phones ,connected to a pbx(NCE 288) that contains the following :
32 analogue exchange lines .
32 analogue extensions
102 digital extensions
the second site , i want to put cisco IP-telephony for almost 20 users but need to integrate the callmanager with the old PBX system .the new site is a migration site and eventually all the analogue phones in the first site will turn to IP and be located in the new site .
on the gateway of the first site . what kind of card should i put to integrate with the PBX ?
can i put FXO or FXS ?( NB:pbx doesnt have E1)
if i put 4 fxo( i said fxo not FXS cause all 32 analogue exchange lines are connetced to pstn, but he has spare extension lines ) on the gateway and connect them to the pbx would the call manager integarte with PBX?
NB: find attached a diagram that will help explain