2025 – Doomsday for BT ISDN and PSTN lines

2025 – Doomsday for BT ISDN and PSTN lines

BT will be switching off their PSTN and ISDN network in 2025. Read more about how this could affect your business and get in touch with our experts.

bt doomsday

As BT draws an end to ISDN/PSTN, you have until 2025 to find an alternative solution to your telephony and business internet requirements.

Fortunately there are a range of solutions available.

We look at the old technology that will be switched off, the reasons for the switch, what alternatives are available and how they can benefit your business.

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Why is ISDN being switched off?

BT introduced ISDN lines nationwide in 1986, and since then connectivity has advanced greatly. The investment and nationwide roll out of superfast internet and Ethernet products provides a viable alternative. However, it is important to note that ISDN is an outdated system that is no longer able to compete with more modern technologies such as VoIP and cloud-based systems. While ISDN still functions, its infrastructure has remained unchanged since the 1980s, resulting in limited reach, features, and quality compared to the more advanced VoIP systems. This discrepancy is evident in the fact that BT has not installed any new ISDN lines in central London since 2014, indicating that many businesses have already recognised the need for a more efficient and effective communication solution.

The transition from ISDN to alternative options is a significant undertaking, involving the switch-over of over 3 million active ISDN users, which is why businesses have been given ample notice to prepare for this change.

What are the key dates for the ISDN / PSTN Switch-Off

The key dates for the ISDN switch off are as follows: The phase out of ISDN will commence in 2020, during which time it will no longer be possible to order new ISDN connections or lines. In 2023, there will be a complete halt on new line installations, line conversions, and channel activations. Finally, in 2025, the ISDN service will be permanently switched off, rendering it unusable. It is strongly advised that by this time, businesses and individuals should have already made the transition to alternative technologies such as VoIP or SIP.

What is a PSTN line?

“The public switched telephone network (PSTN) is the aggregate of the world’s circuit-switched telephone networks that are operated by national, regional, or local telephony operators, providing infrastructure and services for public telecommunication” – Source

Analogue voice data is sent over a circuit-switched phone line made up of copper wires which is owned and operated by your phone provider.

What is an ISDN line?

“Integrated Services Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network” – Source

Put simply your standard telephone line is used to send voice and data over the same line. Therefore you can make phone calls on a home telephone and plug your broadband router in to access the internet using the same port.

What are the alternatives to ISDN lines?

The alternatives to ISDN lines are SIP trunks, which utilise existing Internet connections to carry telephone calls and are described below.

What is VoIP?

VoIP refers to the technology that allows voice communications and multimedia sessions over the internet, converting analog voice signals into digital data packets, and enabling phone calls or video conferencing via the internet.

What is a SIP trunk?

A SIP (Session Initiation Protocol) trunk is a virtual version of a traditional phone line, using the internet to facilitate the connection between your business phone system and the Public Switched Telephone Network (PSTN). Unlike traditional phone lines which require physical connections, a SIP trunk allows you to make and receive phone calls over the internet.

Here is a simplified breakdown:

  1. Virtual Phone Line: Think of a SIP trunk as a virtual phone line that connects you to the outside world, but through the internet instead of a traditional phone line.
  2. Internet-Based: Since it’s internet-based, it can handle voice calls, video calls, and even text messaging, all through one “line” or service.
  3. Cost-Effectiveness: Typically, SIP trunks are more cost-effective as they eliminate the need for physical infrastructure and often have lower calling rates.
  4. Scalability: It’s easier to scale up or down with SIP trunks. If you need more lines, you don’t have to run new wiring; you can just add more trunks through your service provider.
  5. Multi-Functional: Besides voice calls, SIP trunks can handle multimedia communications like video conferencing, instant messaging, and internet faxing, making them versatile for various business communication needs.
  6. Connection to Traditional Phone Network: While SIP trunks use the internet, they still connect to the traditional phone network, so you can call anyone with a phone number, whether or not they have VoIP service.

Top 5 Benefits of SIP and VoIP

  1. Huge savings – Up to a 78% reduction in costs compared to ISDN due to cheaper calls and no more expensive line rental.
  2. Greater flexibility – Move anywhere in the UK and simply plug back into the network with no need to change numbers.
  3. Faster installation – No more waiting for an engineer to install physical lines means you get connected faster.
  4. Higher resiliency – Multiple fibre lines can be installed providing an automatic backup and failover so you’re always connected.
  5. Advanced features – Increased control, integration and analytics offers a huge range of new and advanced features.

Switch today

To find out more about switching to Internet telephony and start using SIP trunks then see our product range here or speak to one of our team on 0345 004 4040. We can also be contacted by filling in the contact us form.

Switch away from ISDN today

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