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Should I be concerned about the end of ISDN?

Should I be concerned about the end of ISDN?


For many years, businesses across the UK have relied on ISDN lines to connect their business phone systems to the outside world. In the 1990s, ISDN lines (Integrated Services Digital Network) represented a huge advance over previous analogue services for voice and data transmission. ISDN provided new functionality with direct dial numbers, options for number presentation on inbound and outbound calls, and a much better utilisation of the total number of lines available to the phone system or switchboard. ISDN also provided significantly improved data speeds compared to dial-up modems.

The world has moved on, and ISDN for data transmission has been replaced by broadband and Ethernet, with their much faster speeds and affordability delivering a winning combination. New technology has also impacted the evolution of voice services, and business-grade VoIP has become widely available, so its adoption is growing rapidly.

As a consequence, Openreach has recently announced that a gradual shutdown of PSTN and ISDN networks will begin in 2020, and this has caused some alarm among companies who like to maintain their familiar ways of doing things. In 2017 over two million UK businesses were still using ISDN connections, so for these companies the clock is ticking.

The end of the road, or a bright new future?

Companies retaining ISDN lines for voice calls are missing out on features like real-time call analytics or remote working, where employees can appear to be at their desks from anywhere in the world. VoIP is endlessly scalable, and numbers are portable away from the local exchange, whereas ISDN is inherently limited. The flexibility of VoIP makes it much easier to cope with business expansion, spikes in call activity and office moves. VoIP also enables full integration with other business systems such as email, CRM and other software packages, which all helps to drive productivity and adds competitive advantage.

The switchover to VoIP is being supported by the efforts of public and private enterprises to install full-fibre connectivity, enabling clear and reliable voice calling for businesses of any size on a ‘converged’ fibre connection that also provides high-speed internet access. Having one high-speed, high-capacity connection can be much more efficient and cost-effective than ISDN lines and separate internet access. Options are also plentiful for building additional resilience with VoIP, safeguarding business continuity and coping with the unexpected.

Openreach’s phased closure programme means now is the time to start thinking about making a change for the better. These are HighNet’s tips for making a smooth transition from ISDN to VoIP and hyperfast internet connectivity:

1. Investigate when your existing ISDN contract ends. Although the switch-off begins in 2020, BT won’t turn its ISDN networks off entirely until 2025. Your contract is almost certain to end before then, which may represent a good time to transition.


2. Learn the benefits of full fibre. These include line rental savings, and much better reliability than the old copper infrastructure. More bandwidth benefits firms who use cloud-hosted software. Early adoption could even provide a competitive advantage over rivals.


3. Research service providers. Many firms have found HighNet’s business connectivity solutions ideal for their needs. Our Gigabit services are fully future-proofed, while we also provide scalable hosted telephony, and for on-premise phone systems provide SIP Trunks to directly replace ISDN.


4. Plan for the future. This is not only the time to consider the possibility of relocating offices, expanding abroad, and so forth – it is the time to develop that roadmap to a more digitally-enabled future. Part of that long-term business plan should ensure any internet and voice services will be capable of supporting you in every way you need.

Evaluating your long-term voice and data requirements and choosing a suitable partner organisation should make the ISDN switch-off plain sailing. If you’d welcome advice tailored for the specifics of your business, the HighNet team will be happy to discuss options. We can help you to identify the perfect communications solutions for your current and future needs.