ISDN Withdrawal – the key questions answered

In this article we answer some of the key questions you may have about the upcoming ISDN withdrawal and the wider closing of the PSTN.

What is the PSTN?

The Public Switched Telephone network or PSTN currently forms a large part of the UK telecoms infrastructure. It is made up of copper telephone lines, fibre optic cables, microwave transmission links, satellites, undersea telephone cables and mobile networks. It used for several functions, including the making of calls using analogue voice data and Supporting digital services such as ISDN.

Why is the PSTN being withdrawn?

According to Openreach:

‘the equipment which runs the PSTN is ageing and will reach its end of life by December 2025.  This means the analogue telephone voice services that are reliant on this network will no longer be available……. Spare parts are becoming out of manufacture and, additionally, many of the people who designed, built and operated the system are retired or close to retirement so skills are increasingly scarce.’

The current PSTN network will be replaced with a fibre and VoIP network.

What products will be affected?

The PSTN network currently supports a number of products which, when it is withdrawn, will no longer be available. The key one which will affect business customers is the Integrated Services Digital Network (ISDN). Many companies have telephony systems which use either ISDN2 or ISDN30 channels to make and receive calls. Over 16 million lines and channels are affected by the swicth off and will need migrating prior to 2025.

When are the services being withdrawn?

Openreach plans to stop allowing the connection of new PSTN services, like ISDN, from September 2023. All connections will be finally switched off in December of 2025.

How will the switch off be managed?

This is still an ongoing discussion. Openreach are in regular discussion with Ofcom and the Office of the Telecommunications Adjudicator (OTA2) about this process. The Federation of Communication Services (FCS) is also involved in these discussions. As a member of the FCS, Deep Blue is part of the wider conversation about how the withdrawal will be managed for communications providers and their customers.

What alternative products will there be?

Openreach are currently in the process of introducing a range of new services alongside some of their existing ones to ensure internet access is available once the PSTN is discontinued. From there, call traffic will be handled as Voice over IP (VoIP). This basically means that your voice call is sent as bits of data via your internet connection. If you are using SIP trunks, Horizon or InBound then you are already making calls via this technology.

I’m using ISDN lines, should I make the switch now?

As always when big changes are happening, some companies use the uncertainty for their own gains. We have already seen customers who have received communications, both at their business and at home, implying their connectivity is under threat and they should move now before it’s too late! This, luckily, is not true. There is still almost five and a half years until the PSTN is deactivated so while it is something to start giving thought to, it is not a reason to rush to make changes.

There are, however, plenty of other good reasons to make the switch. Keep a look out for our article ‘ISDN to VoIP- is it time to make the change?’ coming soon. In it we will detail the many benefits of switching to a VoIP solution: like potential cost savings, resilience and features.

In Conclusion

Many companies are already taking advantage of digital services which will serve them now and after the switch off. For those that aren’t, there is plenty of time and plenty of options for them to make the move to. Openreach, the FCS and service providers like Deep Blue are all working closely to put plans and procedures in place to manage the switch.

Deep Blue customers can rest assured that we will be on hand to make the change as easy and stress free as possible.

Have more questions, want to get ahead of the crowd or keen to start taking advantage of VoIP for it’s many other benefits? Contact Deep Blue today on 0333 240 9100 or by email to theteam@deepbluetelecom.co.uk