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ISDN switch off

Known to many as the ‘BT ISDN Switch Off’, by 2027 every legacy phone line and broadband connection across the UK must be upgraded to a service that uses internet protocol (IP) and runs across a fibre-based network. It’s important that every business understands what they need to do to prepare for life after ISDN. The team at Focus Group are here to guide your business through the transition and help ensure your business is ready for the future of communication.

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What is the ISDN switch off?

Introduced in 1986, the ISDN, or Integrated Services Digital Network, is a telephone network configuration that uses digital transmission to make voice calls, video calls and transmit data (and other network services) via the circuits of the Public Switched Telephone Network, or PSTN. Both the PSTN and ISDN are currently scheduled for decommissioning in 2027.

The ISDN switch off is a nationwide analogue to digital switch that will see the old copper phone network turned off and the country switched to fibre in 2027.

For businesses, this means that you will have to implement an alternative to ISDN lines (and any hardware that uses them). So, it’s time to upgrade your telecoms and connectivity to ensure your business stays in touch and ready for an all-digital future!

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Farewell ISDN, hello full fibre!

What is the difference between ISDN and PSTN?

The ISDN switch off and the PSTN switch off are the same ‘event’ but refer to two different networks that transfer voice and data over the UK’s phone lines and that will be switched off at the same time. The PSTN is a ‘circuit-switched’ analogue system requiring an operator, a telephone exchange and a pair of overhead wires to function. The ISDN is a digital-based network, offering end-to-end connection to allow for telephone calls and other non-voice services.

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Why is ISDN being switched off?

With the rapid growth of digital communications, the Integrated Services Digital Network is unable to manage the increase in activity and quality that modern businesses currently require. This has been compounded by the high costs of maintenance, the convenience of VoIP (Voice over Internet Protocol) solutions and the speed of fibre-based broadband connections.

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When is the ISDN switch off happening?

The ISDN switch off is happening in 2027 and aims to be completed by the end of December that year. You will be able to purchase new ISDN lines until September 2023. After that, no new ISDN lines will be installed or added. There will be a ‘forced migration’ phase between May 2024 and January 2027 (the nationwide stop-sells). Be aware that different areas may have different stop-sell dates. Businesses will benefit from switching over their infrastructure early, as they will avoid the risk of costly disruptions.

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How will the ISDN switch off affect me?

The communications (and some security) infrastructure will be affected by the ISDN switch off. In short, any hardware that is not VoIP compatible, or uses your ISDN phone line, will not work after the switch. If these changes are not made in time, businesses with redundant systems will incur costly expenses and disruptions to their networks.

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What do I need to do? What are the alternatives to ISDN?

As traditional ISDN lines can’t meet current demands, your ISDN communications infrastructure will need to be replaced with technology that uses internet protocol (IP) and runs on the new fibre-based network. This means that you will need to upgrade to VoIP (Voice over Internet Protocol or IP telephony) technologies, which transform analogue calls into packets of data and are delivered over IP networks. This can be achieved by using SIP (Session Initiation Protocol) trunking, which allows you to make calls using a data connection, or by switching to a fully hosted cloud system.

Focus Group is well placed to support your business through this transition, at no additional cost. We’ll ensure you have everything you need well ahead of 2027, from a VoIP phone network to the SIP trunking system, leaving you free to focus on the important stuff like growing your business.

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Benefits of the ISDN switch off

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Future-proofing

With the explosion of remote working opportunities and digital entrepreneurial ventures, the UK’s antiquated ISDN lines are no longer fit for purpose. Fibre-based networks are much better placed to fulfil the existing, and future needs, of communication.

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Better speed & quality

With better speeds and call quality, a shift to the new infrastructure will aid businesses in their expansion and productivity goals.

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Lower costs & flexibility

Fully digital services that run over the internet, like VoIP technologies, mean little or no cost for phone calls and a much more flexible service. No matter where you and your employees are located, you’ll stay connected.

Frequently asked questions

The PSTN and ISDN are two different networks that transfer voice and data over the UK’s phone lines. The PSTN is a ‘circuit-switched’ analogue system and the ISDN is a digital system. Both systems will be switched off in 2025.

VoIP (Voice over Internet Protocol or IP telephony) technologies transform analogue calls into packets of data, which are delivered over IP networks. The ISDN, or Integrated Services Digital Network, is the antiquated telephone network configuration that uses digital transmission to make voice calls and transmit data. ISDN will be discontinued in 2025 and all services must be upgraded to VoIP technologies.

The advantages of the ISDN are that connections can be launched quickly, many devices can be connected to a single line and it provides a high data rate. However, it is very costly and requires specialised digital devices. After the network is switched off in 2025, ISDN networks will no longer be used in the UK.

The ISDN, or Integrated Services Digital Network, is a telephone network configuration that uses digital transmission to make voice calls and transmit data. SIP trunking will allow businesses to make calls using a data connection after the ISDN network has been switched off.

Businesses will need to upgrade their traditional telephone system to an internet-based or hosted VoIP phone system. This can be accomplished by using a SIP (Session Initiation Protocol) or by switching to a fully hosted cloud system.

Focus Group can help you with your entire transition process from ISDN to hosted VoIP technologies at no additional cost to your business. There is a huge range of VoIP business phone systems so the team at Focus Group are here to help. We’ll take a look at the specific requirements of your business, discuss all the options available and help you select the best system to suit you.

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