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Overview

High performance voice and data service

What is ISDN?

Integrated Services Digital Network is a high-performance service that delivers broadcast-quality voice and continuous, extremely reliable data transmission.

Continuous data transmission makes it ideal for use with EPOS machines and intelligent tills in shops, especially in areas with patchy broadband coverage.

ISDN2

For small businesses that cannot afford any breaks in data transmission.

With ISDN2 System you can connect to a small switch (like the BT Quantum) with up to 60 channels.

Channels are sold in pairs and can be bonded to increase bandwidth for things like reliable video-conferencing.

ISDN30

For large businesses that need high-quality video-conferencing, consistent transfer of large data files, or that operate call centres.

As well as being able to have an unlimited number of channels (sold singularly), ISDN30 customers can also bond channels to increase bandwidth.

ISDN30 supports WAN to link 2 or more sites.

Included as standard

Help and support

We will aim to fix your phone line fault by the end of the next working day.

You can report faults 24/7/365 online or by phone:

ISDN2 & ISDN2 system call - 0800 800 154

or

ISDN30e call - 0800 154 434

But you may not need to contact us at all: our comprehensive set of FAQs and help articles on our website, plus help from other customers on our support forums,  should answer most questions.  

 

Optional extras

ISDN30 Assurance Continuity: alternative and diverse routing

Protection against both cable and local exchange failure.

 

  • We provide your ISDN over 2 different routes
  • Different cables, ducts (where available), and building entry points
  • Routing from 2 exchanges to your premises

ISDN30e Assurance Continuity: site assurance option 1

If your site has been compromised, we’ll divert all your incoming calls to a single pre-arranged number.

ISDN30e Assurance Continuity: site assurance option 2

ISDN30e channels duplicated at a standby site that we activate when you can’t use your main site.

ISDN30e Assurance Continuity: dual parenting

We connect your site to 2 exchanges with the same number range across both exchanges. 

So if one exchange fails, you’ll still get your incoming calls delivered from the second exchange.

Add more DDI numbers to your ISDN30e

If you’d like to add direct dial in numbers to your lines you can upgrade from £3.20 per channel per month.

Faster fault fix

2 options for more rapid fault fixes.

Total care

We will aim to fix any faults within 24 hours of you telling us about the fault (including weekends and public holidays).

Costs

ISDN2 and ISDN2 System: £4.40 a month extra for each pair of channels

ISDN30e: £2.80 a month extra for each channel

Critical care

We will aim to fix any faults within 6 hours of you telling us about the fault (including weekends and public holidays).

Costs

ISDN2 and ISDN2 System: £5.90 a month extra for each pair of channels

ISDN30e: £3.30 a month extra for each channel

Increase your call allowance

Save money by increasing your call allowance.

ISDN2

  • Inclusive call allowance of £20 a month – from an extra £12.00 a month
  • Inclusive call allowance of £40 a month – from an extra £24.70 a month

Why BT Business?

Unlimited UK calls for just £10 a month
With over 900k customers, more businesses trust us with their communications
24/7/365 online fault reporting and service status for your area
1000s of business lines are brought back to us each month

Techie stuff

ISDN2

Technical details about ISDN2.

  • Internet connection speed on each channel is 64kbps, which you can combine for faster transmission
  • If you connect devices directly to the ISDN circuit, you can have up to 9 additional MSN (Multi-Subscriber Numbering) numbers

ISDN2 System

Technical details about ISDN2 System.

  • If you connect devices directly to the ISDN circuit, you can have up to 9  additional MSN (Multi-Subscriber Numbering) numbers
  • Internet connection speed on each channel is 64kbps, which you can combine for faster transmission
  • Bond channels together for faster transmission for high-quality video conferencing and transferring large data files
  • If you use a switch (PBX), you can have an unlimited number of DDI numbers (extra charges apply)

ISDN30e

Technical details about ISDN30.

 

  • Each bearer carries 30 64kbps channels
  • Bond channels together for faster transmission for high-quality video conferencing and transferring large data files
  • If you use a switch (PBX), you can have an unlimited number of DDI numbers (extra charges apply)
  • You can create a Wide Area Network (WAN) by linking 2 or more Local Area Networks (LAN) so you can link multiple sites together
  • 2 configurations available: ETSI and DASS

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