With the upcoming PSTN and ISDN Switch Off, businesses still using these networks will need to update their systems to avoid any service disruptions. Beyond the traditional phone systems, this technology is used for several other functions as well. Carrying out a thorough audit with assistance from an experienced business will be crucial to minimising cost, reducing risk and ensuring your systems are set for future growth.
The Public Switched Telephone Network (PSTN) is the traditional analogue phone network, which relies on copper wire, circuit-switched lines. The Integrated Services Digital Network (ISDN) updated the PSTN lines, allowing for many different communications to travel down the same line.
But with the upcoming PTSN and ISDN Switch Off, these networks will be shut down altogether.
This seismic shift in telecom infrastructure has far-reaching implications, with not just phone networks being affected but a whole myriad of other technologies that have historically relied on these lines. The days of analogue are truly over, with the key date in mind being December 2025 for the official Switch Off.
The process of change, however, has already begun, with 2023 seeing the end of new ISDN / PSTN infrastructure sales and many businesses updating their networks for the last few years in preparation for the change.
The ISDN networks will need to be changed to IP connections (Internet Protocol). For the PSTN migration, this will be through Voice IP (VoIP). In this switch to internet-based connections, there are two driving benefits:
Aging infrastructure: the lines used by PSTN and ISDN require more maintenance which greatly increases the running costs.
IP’s greater efficiency: transmission of data through internet-based connections is more efficient, reliable, and cost-effective.
Though phone networks are one of the key systems being affected, it’s worth noting that there are other technologies that also use these networks. If you are a business with one of the following, you could be affected:
A lack of preparation for the PTSN and ISDN Switch Off could lead to disastrous results for companies that are still reliant on traditional PSTN / ISDN infrastructure.
For those relying on these traditional networks, without taking the necessary steps they could see a blackout in communication and major disruption of service for their customers. Similarly, for those using them for security measures, the shutdown could lead to vulnerabilities across their estate, leading to expensive reviews and last-minute fixes.
Whilst December 2025 still seems far out, the extensiveness of these networks means migrating to new technologies can take time and consideration. Imagine you have a whole apartment block full of copper-wired phones and you need to explain to every single person in there the Why and What work needs to be done. Time is of the essence if you want to transition smoothly.
Being ill-prepared for the change will most likely mean paying a premium for last-minute solutions while managing breakdowns in service and, ultimately, a missed opportunity to innovate across your infrastructure.
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For businesses with extensive legacy systems in place, the PTSN migration can seem rather daunting. Several questions should be at the forefront of your mind during this period.
Navigating these questions requires both key technical knowledge and a deep understanding of the business impact.
With over 30 years of experience in the telecoms industry, at StableLogic we put concerns to rest with our diligent approach. We provide an end-to-end service that both removes the headache and ensures your business is equipped for maximal future growth. Here is how we tackle the task.
We begin by conducting a thorough inspection of your current infrastructure and the locations of PTSN or ISDN dependencies. But most importantly, we gain an understanding of your communication needs, to ensure the new system meets them.
With our assessment in place, we develop a tailored transition strategy that aligns with your needs and goals. We prioritise to minimise risk to any critical systems and potential disruption.
Our team is on hand to help conduct the changes, coordinating with the different providers and stakeholders and test the new system.
We maintain a watchful eye over all compliance and regulatory issues during the transition to maintain confidence for your business regarding security matters.
With the system in place, we provide consultation on how to make the most from it regarding future cost-efficiency.
The PSTN replacement is an imminent transformation that affected businesses cannot afford to ignore. StableLogic specialises in digital transformations with over 30 years of experience. Remove the risks and headaches with our help and make the swap to IP-based technology a success story of your own.