ISDN: BRIs and PRIs

ISDN (Integrated Services
Digital Network) comes in two flavors: BRI and PRI. ISDN BRI (Basic Rate Interface) use a single pair of copper wires, and has two 64k channels that can be used for voice or data, and one 16k D channel that controls the other two channels. ISDN PRI (Primary Rate Interface) is the T-1 version of the service and has 23 64k B (voice or data) channels and one D 64k D channel. PRIs are most often used in PBX phone systems, and analog and digital modems used by ISPs.

VOICE AND DATA

With ISDN BRI service you can connect digitally to any other ISDN customer, or Internet provider and be assured of getting a full 64 kbps. per channel. Most ISPs have equipment that will allow you to bond the two channels and form a 128k circuit. However, ISDN BRI service is normally sold with a limitation 320 total hours of use for outgoing calling. If you use dual channel, then you cut that time to 160 hours included in the price of the service before you have to pay 1 penny per minute per channel. If you don't set your router to drop the call when the circuit is not in use, this can cause an additional charge of over $400 per month! However, if you set it correctly, and that means that no computers are left on checking email every few minutes 24 hours a day, most small businesses will not go over the time limits with normal usage. Unmeasured BRIs are available, but they cost more. Call or email us for pricing in your area.

ISDN BRIs are also often used for Video Conferencing. One to three BRIs are bonded to create a clear channel digital circuit from one location to another. However, if it's toll call to connect locations, you will be billed long distance charges for each line.

CLICK HERE TO FIND OUT MORE ABOUT ISDN-BRI

ISDN PRIs FOR VOICE & DATA

Most of today's new phone systems can utilize ISDN PRI service. PRIs offer the highest level of service and flexibility. By using the D channel for Out of Band Signaling, one can utilize any of the 23 B channels dynamically. With standard T-1 service, the channels are statically assigned a specific function, e.g. if you have DID service on an regular T-1, a specific number of more expensive DID channels are assigned to handle the DID calls. Once these channels are full, the caller gets a busy signal, even though there may be other trunks on the T-1 that are not in use. When you have PRI, you can point any number of $.20 each telephone numbers at PRI and the PBX will direct them as programmed. Also, there's no DID charge and no hunting charge because the PBX switch determines these functions, and communicates directly with the Central Office.

Calling Line ID is standard on a PRI. If you wish to have Calling Name, that feature is optional. PRIs are flat rated (unmeasured), have faster call set up time and also provide answering supervision of the call. That means you won't pick up your phone to make a call and wind up answering an incoming call, and your PBX can do a better job blocking fraudulent toll calls.

ISDN BIS PRI T1s with voice and internet on the same T-1 are also available.

Click here to FIND OUT MORE ABOUT ISDN-PRI

Call us toll free for the most current promotional plans 866-212-2355.