Are you ready for the big PSTN and ISDN switch off?


Lindsay Harriss


17 Jan, 2022



In case you are not already aware, BT Openreach announced in 2015 that it will be turning off its public switched telephone network (PSTN) and integrated services digital network (ISDN) in 2025. This news seems to have slipped under the radar of many businesses, despite being possibly the biggest telecoms shake up in 30 years! So, what is this all about, and how will it affect you? We look at what this means for UK companies and what you need to do to prepare now.

Firstly, for the uninitiated, let’s get down to the nitty gritty – what on earth are PSTN and ISDN? Well, PSTN is the system that enables landline connectivity, and was originally set up to facilitate analogue voice communication. It is made up of all the circuit-switched telephone networks in the world, operated by local, national and international carriers, letting users make landline telephone calls to each other. A call is placed after it is routed through multiple switches, enabling voice signals to travel over the connected telephone lines. This system has provided us with a reliable means of communication, using copper-cable telephone lines, since its inception in the late 1800s. ISDN, on the other hand, which was introduced in the 1980s, was the first version of high-speed Internet, facilitating the digital transmission of voice, video and other services, using the traditional PSTN system, and offering better voice quality. However, time moves on and although this telecommunications technology has served us well over the years, it has now become outdated, and is not cut out for modern purposes.

What’s happening?

With the likes of 5G and the Internet of things (IoT) propelling technology into the future, the nationwide move from a telecommunications network rooted in the 19th century to a digital system may seem long overdue. Therefore, recognising that the future of phone communications now lies in Internet-based telephony, BT Openreach will begin the process of turning off the traditional phone network this year, and it will finally be switched off entirely by 31 December 2025. This means that all UK telephone users will have to migrate to an Internet Protocol (IP) telephone system (also sometimes referred to as voice over Internet Protocol (VoIP)) before the final switch off comes. In fact, the UK is not alone in making this move, as this has been happening around the world, with countries such as Germany, Sweden and Japan well ahead of us in migrating to digital. Although you may think that 2025 is still some way off, it really is just around the corner now, so it is important for businesses to start making plans as soon as possible.

What’s the big deal?

When you consider that good communication is key to the success of every business, and simply speaking to others remains vital, you really cannot afford to drag your feet when it comes to ensuring your company communication system remains up and running, and is fully future-proofed. After all, as an iconic BT ad campaign once said, ‘it’s good to talk’. However, the big switch off will have an impact on far more than just voice communication, as it will also affect any technology that relies on a traditional telephone line, such as electronic point of sale (EPOS) systems, emergency lift phones, CCTV and door entry systems. So, it is vital that organisations make preparations well in advance of the deadline, to avoid essential facilities ceasing to work.

Yet, rather worryingly, despite the importance of this issue, a recent survey by National Business Communications found that only one in five firms are fully aware of the big switch off, while 59.7% have no idea what it is at all, and 69.5% of UK businesses are still using landlines within their organisation. Similarly, research conducted by Zen Internet, found that 72% of businesses were reliant on traditional telephony, even more so in large organisations, and a third of SMEs were not aware of the impending switch off, while 17% of large companies were also still completely in the dark about the issue. So, this does suggest that businesses need to step up the urgency a notch, if they want to ensure they are ready in time and not caught out.

What are your options?

However, although this really is quite a big deal, DON’T PANIC! There is still time to make sure that your business’s communication system is brought up to date, but what are your options? Well, you have a range of choices, but if your organisation is still relying on traditional phone lines, doing nothing is not one of these. While the thought of having to change your business telephony may be stressful, in reality it can be quite straightforward. With a variety of cloud, on-premises and hybrid solutions available to choose from, you can tailor your telecommunications system to meet the specific needs of your business, and it could help your organisation to operate far more cost-effectively and efficiently in future.

For example, if you opt to move to a cloud-based unified communications system, you can enable your workforce to make voice calls as well as message teams, conduct videoconferences, file share and more, all from one platform, on any device, from anywhere. This flexibility is invaluable in today’s new business world, where remote and hybrid working is now the norm. Such a system can help to accelerate business decision making as well as enhance customer experiences, and is easily scalable to fit in with future needs. In fact, if, like so many organisations since the onset of the pandemic, you are already using Microsoft Teams to keep your workforce connected, with the aid of direct routing, you can even choose to use this for external, enterprise-grade voice calls.

Alternatively, if your company is a larger organisation that currently has an on-premises private branch exchange (PBX), which you would like to continue using, it may be possible to adapt it using session initiation protocol (SIP) trunking, to route calls through your on-site Internet connection, if your PBX supports IP telephony. However, if all this still seems a tad confusing, Prodec Networks offers free discovery sessions which provide guidance from highly skilled business communication experts, to help you find the very best option for your business.

Further considerations

Finally, in order to ensure a smooth transition to this new telecoms era, there are a couple of further considerations it would be wise to take into account. If you need to move over to a whole new communications system and want to keep your existing phone numbers, this is usually possible, as you can normally port these over to the new service. However, you do need to allow time to do this, as the process can take a little while. In addition, as all your voice calls will be Internet based in future, it is crucial that your connection is robust enough to support all your IT needs. You may therefore want to review your connectivity and upgrade it, to strengthen this, if necessary.

For help with preparing for the big PSTN and ISDN switch off, and all your business technology needs, contact Prodec Networks today.

Next steps

We understand the decision to upgrade, replace or relocate your telephone system can cause stress and worry. That doesn’t have to be the case. To get started simply click the link below.

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