A PRI (Primary Rate Interface) line is a form of ISDN (Integrated Services Digital Network) line which is a telecommunication standard that enables traditional phone lines to carry voice, data and video traffic, among others.

A PRI circuit consists of two pairs of copper lines terminating on a modem from a service provider premises to the customer premises. It uses multiplexing/de-multiplexing techniques to carry more than one channel in a single circuit.

Each channel in a PRI line provides 64 Kbps for data transmission.

A PRI line can connect to both Analog/Mixed EPABX systems and also the newer IP PBX systems. A PRI Card / Interface might be required to terminate the PRI circuit on the PBX.

A PRI line can also be used to connect two PBX systems thereby providing 30 channels between them for interoperability.

CHECK THIS LINK :- http://www.prilines.co.in/

SIP Trunking

Session Initiation Protocol – or SIP – is the method of transmitting a voice communication over a data network. A voice over IP (VoIP) call is an example of a SIP session.

SIP trunking is sort of like a POTS (remember – plain old telephone service). But, with SIP trunking there are no phone lines running all over the place. Instead, the ‘lines’ are virtual because the phone system is connected to the service provider through your network (your internet connection).

HOSTED PBX

Hosted PBX (Private Branch Exchange) is a telephone exchange system that’s accessible over a cloud-based IP network. Because it’s cloud-based, access to this telephony solution is granted entirely over the internet, cutting down on hardware and software costs.

Hosted PBX is a solution that’s managed completely off-site, making it so businesses no longer have to invest in expensive infrastructure, software, and training. It is quickly set up and deployed, in some cases even granting users access in less than a day, and is primarily hands off when it comes to maintenance (thanks to it being cloud-based).

Session Initiation Protocol

Session Initiation Protocol (SIP) is used to signal and control interactive communication sessions. The uses for such sessions include voice, video, chat and instant messaging, as well as interactive games and virtual reality. The SIP protocol is increasingly being used to provide Voice over IP, Presence and Instant Messaging in Next Generation Networks, and being mandated for many new applications, including 3G telephony.