What is PRI?

ISDN (Integrated Service Digital Network) is divided into two types of services, BRI (Basic Rate Interface) and PRI (Primary Rate Interface). BRI is mostly used by smaller enterprises, PRI is meant for medium and large enterprises as well as smaller companies who require a high number of parallel calls.

PRI scheme

Both, BRI and PRI are consisting of B and D channels. B-channels carry voice (or data), D-channels carry control and signalling information. BRI consists of two B-channels and one D-channel. PRI is often referred to as T1 (for North America and Japan) and E1 (for Europe and Australia). T1 usually has 23 B-channels and one D-channel, E1 usually 30 B-channels and 2 D-channels. Additionally, there are PRI pairings available consisting of multiple T1/E1 lines, as well as fractional T1/E1 lines with less than 23/30 channels.

PRI module for AskoziaPBX

AskoziaPBX now supports Plug&Play installation of Allo and OpenVox PRI cards without any additional drivers. Just plug the card into your system and boot AskoziaPBX – It-just-works
It´s possible to configure E1/T1 in seconds without any expert knowledge.

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