Adding PSTN lines and Trunks Fig 3
Adding incoming connections to your softPBX for existing PSTN Lines. Adding new trunk for Incoming numbers and outgoing calls
In order to incorporate existing PSTN lines into a VoIP system you need to add an interface card into the softPBX. The simplest way of accommodating to existing DDI lines is to add an interface card into the trixbox server that has one or more FXO interfaces on it. Each FXO will answer a call on one conventional POTS line. Interface cards are available to connect ISDN, E1 and T1 lines so that larger telco lines can also be connected to your softPBX.
