PRI T1 Lines: Primary Rate Interface Service | T1 PRI Prices

Primary rate interface is a service provided to large office buildings as well as large businesses. Primary rate interface (PRI) is considered to be the standard telecommunication service. If the service is provided in the US or Canada, PRI T1 lines would be what the service is based on. If the service provided is in Europe the service is based on E1 (Europe 1) line. T1 lines are lines which are not specific lines for telephone carrier databases. PRI T1 is specific to data and voice transmission.

Primary Rate Interface (PRI) provides an array of different channels which are dependent upon the country where the service is held. For example, if the service is held in the US or Canada, the T1 lines consist of 24 channels. If the service is held in Europe, the E1 line consist of 31 channels. PRI is only available in the US, Europe and Canada.

There is a set of communications standards for digital video, voice, data, and other network transmission. This an array of communication is called Integrated Services Digital Network (ISDN). ISDN provides two different levels of service, PRI and Basic Rate Interface (BRI). PRI is used for larger businesses or enterprises, while BRI is for smaller homes and businesses.

PRI and BRI: What are they?

PRI and BRI both have several channels which carry different types of information. These channels are labeled B-channel and D-channel. B-channel carries voice, data, and other services. The B-channel also carries data which is considered primary. D-channel is a carrier signaling and controlling information.

As previously stated, PRI provides service to larger enterprises while BRI provides service to smaller enterprises. Because of this, PRI is larger than BRI. PRI T1 line consists of 23 B-channels and 1 D-channel. The E1 consists of 30 B-channels and 1 D-channel.

There is a possibility of obtaining a larger connection. Pairing PRIs would enable a larger connection to occur. A primary rate interface could have 47 B-channels if 23 B-channels was added to a 23 B-channel. This type of pairing is called 47B+D. The more common pairing, however, is 23 B-channel plus 23 B-channel. It is not advised that more than 2 D-channels be paired. If more are desired or needed, more PRIs can be added.

Applying Primary Rate Interface

1.472-Mbits of data service are available for Primary Rate Interface (PRI) T1 users. For PRI E1 users, 1.920-Mbits of service is available.

The primary rate interface (PRI) is primarily used by med-large businesses with Private Branch Exchanges (PBXs). These digital PBXs are exchanges for telephone systems that are provided for a specific enterprise instead of many businesses or for the general public. PBXs give theses businesses digital access to Public Switched Telephone Network (PSTN). PSTN is a telephone network that spans all over the world. PSTN has several different features, such as phone lines, cables, fiber optics, cellular networks, underwater telephone cables, microwaves, and communication satellites.

23 B-channel which is 30 in Europe, can be suited in order to fit the needs of each individual user. It can also do such specific tasks like video conferences.