| Recently, you may have been hearing a lot about | | | | A T1 line consists of 24 channels, which can each |
| T1 PRI services, but what exactly are they? T1 | | | | be used to serve a different purpose. All of them |
| PRI can be best explained by separating these | | | | may be used to deliver 24 individual phone |
| two individual aspects. | | | | threads to a location, or may all be used to |
| The term PRI refers to Primary Rate Interface. | | | | deliver bandwidth for data networks and Internet |
| This is provided by the ISDN, or Integrated | | | | connections. Alternatively, the 24 channels may |
| Services Digital Network. ISDN provides two basic | | | | be split up and dedicated to voice or data in any |
| levels. The first, and most common, is known as | | | | combination, such as 12 lines of voice and 12 lines |
| BRI, or Basic Rate Interface. The second is | | | | of bandwidth. |
| known as PRI, or Primary Rate Interface. Both of | | | | When used for bandwidth, each channel is capable |
| these utilities are a method in which many voice | | | | of delivering 64 Kbps of data, meaning that a T1 |
| and data transmissions can be sent and received | | | | line fully dedicated to bandwidth will provide 1.54 |
| over a single fiber-optic cable. | | | | Mbps of data. |
| BRI provides 3 independent lines that can be used | | | | The real beauty of the utility is that the customer |
| for voice or data. PRI is more robust and uses 24 | | | | basically leases the T1 line itself. This means that |
| channels to support individual threads, making it | | | | the it is dedicated to this customer alone, |
| more geared towards businesses or other | | | | providing reliable bandwidth for networking or |
| situations that require many voice lines or larger | | | | Internet use at all times. This is as opposed to |
| quantities of bandwidth to be delivered. | | | | traditional methods of data delivery, in which lines |
| T1 service is actually not a service at all, but | | | | are reused over and over and shared by several |
| should be thought of more as hardware. This | | | | users, decreasing the quality of the connection. |
| type of thread provides the necessary means for | | | | This is a process known as "switching" and can |
| PRI service to be delivered to a location. In short, | | | | significantly decrease the quantity and quality of |
| PRI is the actual service, while T1 is the hardware | | | | bandwidth being delivered. |
| used for delivery. | | | | |