Your guide to ISDN30 and ISDN30e

For help using ISDN30/30e, go to our guide.

ISDN30 and ISDN30e are high-performance voice and data services for modern businesses with eight or more employees.

Each ISDN30/30e connection provides 8-30 independent 64k channels. You can combine these for bandwidth-hungry applications like high-quality video conferencing or transferring large data files but usually you’d use them separately, meaning you can get simultaneous calls over each channel. You can also add further connections to increase the number of simultaneous calls and/or available data bandwidth, if you need too.

ISDN30/30e is ideal for wide-area networks linking two or more offices.

Other advantages of ISDN30/30e:

• Connections are almost instant.
• Voice communications with other ISDN users are crystal clear.
• You can send and receive calls to all telephone subscribers, whether they use digital or analogue equipment.
• Data transfer is fast and error free.
• There's a wide range of compatible equipment, giving you access to the latest digital technology.
• You can provide your staff with individual DDI numbers.

ISDN is supported by most local exchanges so you should be able to get it, but a site survey is needed for every new order. If it isn't enabled at an exchange, we can usually enable it but there would be an additional installation charge. 

When your survey is complete, it can take up to 20 days for a new ISDN30/30e service to be installed.

Interested? Find out all you need to know and how to order ISDN30/30e here.

You can use ISDN for voice calls and for high-quality data links with other ISDN subscribers. Digital connections are often used for transferring large files securely, for video-conferencing and for linking Local Area Networks at different sites. You can make data calls to other countries that have ISDN services.

Devices

With ISDN30/30e you have a choice of feature-rich digital switch/PBX equipment, available from BT and other suppliers. There is a wide range of digital devices, including telephones, fax machines and ISDN cards for computers. Go to our sales pages to get more information on equipment.

Telephone numbers

You can have an unlimited number of DDI numbers, allowing customers and business contacts to dial directly through to staff members, without passing through a switchboard.

Connecting to the internet

Using an ISDN PCI card you get fast internet access. If you're thinking of moving from an analogue telephone connection to ISDN, you should check that your current Internet Service Provider (ISP) supports access. You might be asked to dial in to a different number.

If ADSL is not yet available in your area, you can connect to the internet at 64kbps using one ISDN channel, or at 128kbps using two channels together. To find out more, go to Getting started with ISDN30/30e. Since each channel is a true 64k connection, you’ll find that even one channel performs significantly better than a 56k dial-up connection (for an analogue dial-up modem, 56k denotes the maximum speed possible, not the average connection speed).

Comparing ISDN30 and ISDN30e

There are a number of BT Digital Calling Features (formerly known as Digital Select Services). These include Call Forwarding, Call Barring and Calling Line Identity (CLI).

ISDN30 uses the BT signalling system DASS2, while ISDN30e uses the Q931 signalling system which conforms to the worldwide ITU-T standard. The range of Digital Calling Features available on these systems is slightly different, as shown in the table below.

Most BT Digital Calling Features are controlled by your equipment. They don’t use pre-set codes such as 1471.

*For customer-controlled service features, your switch/PBX must be able to activate the service. Consult your supplier for more information.