What is ISDN 2?

Formerly known as OnRamp 2, ISDN 2 business phone lines transforms your existing analogue telephone line into two digital connections. ISDN2 features are;

• Two telephone numbers on the one ISDN 2 phone service.
• With ISDN 2 there are two digital channels capable of transferring both voice and data at bandwidth rates of 2 x 64kbps or 128kbps when 2 lines are combined
• Only one service line is required for telephones, faxes or computers allowing you to use the other line to work remotely in the field or at home or can be used for a 2 nd voice line.
• An ISDN2 service must be connected to an ISDN compatible PABX system at the customers premises
• With ISDN 2 you can access a 100 Number Direct Indial (DID) range so even if you only have 2 lines you can have 100 numbers.

A full explanation of the range of features available on an ISDN 2 service is located here.

What is ISDN2 Enhanced?
ISDN2 enhanced services are identical to standard ISDN2 services but are supplied with an integrated network termination device and router. Since this hardware is more expensive to supply, the monthly line rental is a few dollars higher than standard ISDN2.

The integrated unit supplied currently is the Open Networks NT1 plus II . This unit allows the customer to connect multiple computers on a small LAN to the ISDN service to leverage the ISDN investment. The NT1 plus II also allows customers to "bond" the two channels together for 128kbps internet access when no phone lines are in use. Although these units require mains power they have the ability to keep the main phone line active during a mains power failure.

Why Use ISDN2 Phone Lines?

• ISDN 2 Phone lines are Digital business phones lines delivering clearer and faster phone calls.
• ISDN 2 are a scaleable service in that you can add an additional set of lines in increments of 2 lines at a time. eg start with 2 lines and add in 2/4/6/or 8 ISDN2 services as required.
• ISDN 2 gives you the availability of a 100 Number Direct in Dial range. Even if you only have 1 or 2 ISDN 2 services you can have 100 phone numbers or more. ISDN 2 is ideally suited to small to medium business that require crisp clear digital communication lines in conjunction with a PABX phone system. ISDN 2 Business phone lines have access to all the great business phone line features you need including Line Hunt & Caller ID.

For more than 10 channels you will require and ISDN 10/20/30 service.

A full explanation of the range of features available on an ISDN 2 service is located here.

How do I connect to ISDN2 Phone Service?
As ISDN is digital, there is no need for a modem. However, a customer will need a terminal adapter to receive the ISDN service. A terminal adaptor enables the communication from the user's terminal to the network and serves as an interface between the ISDN BRI line and the customers equipment.

Terminal adaptors are sometimes referred to as Network Termination (NT) devices or ISDN modems/routers, although this latter term is slightly misleading.

The terminal adapter is provided by the ISDN service provider.

To connect the customer's local area network (LAN) to an ISDN2 service the customer will require a separate ISDN router or (as is more common) a terminal adaptor with a modem / router built in.

Customer wishing to connect a LAN to an ISDN2 service should choose the ISDN2 enhanced service.

A full explanation of the range of features available on an ISDN 2 service is located here.

Tony Dunphy is Managing Director of Telaustralia an Australian Business Phone Company.