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Are you ready for the PSTN and ISDN switch off?

(Image credit: Image source: Shutterstock/Toria)

The PSTN and ISDN networks are being switched-off in 2025, meaning organizations will need to move to more modern, IP-based telephony as a matter of urgency. At the point of writing, businesses have under five years to migrate their critical voice systems or face losing contact with customers entirely. On the surface this sounds like a lot of time, but according to research by the Cavell Group, there are many businesses yet to migrate.

In 2019, the UK cloud communications market grew by over 800,000 users at a rate of 20.14 percent and the SIP market grew by over 200,000 at a more modest 4.74 percent. In 2020 these figures accelerated as organizations expedited their IP telephony migration strategies in response to the remote working requirements imposed by Covid-19.

While many organizations have now made the move to IP, the research suggests there are hundreds of thousands of organizations around the country facing the significant challenge of migrating infrastructure. Depending on the complexity of that infrastructure, these migrations could take months and there are some organizations with old PBXs potentially staring down the barrel of significant investment to keep up with necessary change.

Which begs the question: are you ready for the switch off?

How to tackle the impending change

If you are one of the organizations still on PSTN / ISDN infrastructure then you might be reading this and wondering what to do next? Well, you aren’t alone, and there are plenty of solutions available for you capable of matching your required functionality (and most likely provide you a little more besides).

But before you can begin with any of that, you need to conduct a thorough audit of your existing technology deployment, connectivity, and everything else relating to your communications ecosystem. When critical customer communications are involved, you can’t afford to make mistakes since any downtime can cost you thousands in lost revenue or repairs.

Why you need to begin planning your migration now

When done right, SIP / IP migrations are relatively simple, but it’s a process that can take a long time. And, with the deadline looming, many businesses are facing the need to make the change at the same time, meaning there could be longer lead times the longer you put it off.

The big question is: are you ready for the necessary migration?

Assessing your current infrastructure

Before jumping in, you need to know your current situation and if you’re ready for SIP/IP technology. Spend time understanding your infrastructure and identify colleagues who can help you make your migration successful. Communications are utilized by the entire business so don’t be afraid to extend the net and hook in some of your colleagues to support.

Whether you’re a public sector organization with multiple sites, a critical blue service, or a retailer with different telephone systems in every store, you need to catalogue your entire estate. Yes, everything.

Think about how many locations you have, whether you have a unified platform or independent silos, what type of transport and the amount of bandwidth you have at each site, and list all the telephone numbers you own.

Make sure to take stock of the call volumes and make a note of any numbers you can lose in the switch over. Take this as an opportunity to right-size your estate, stripping away unnecessary costs and rebalancing your expenditure to better reflect what you’re going to need in the future.

Planning for a migration

With your catalogue complete and your infrastructure review finalized, you can now begin planning. This is without a doubt the most critical step. You will need a thorough plan to keep you on track, identify issues, keep teams aligned, and ensure a successful migration.

Review your infrastructure and hardware catalogue and figure out what’s primed and ready for the move to IP or SIP.

- Software: does your existing system support SIP natively? Are you going to go straight to cloud/hosted PBX or simply replace your ISDN lines?

- Hardware: Is your on-premise PBX ready for SIP trunks? Are you going to need new hardware?

- Security: Have you evaluated the integrity of your communication infrastructure? Do you have a failsafe/backup in place should you need it?

Identifying a provider

With a plan in place, you can begin to review a potential provider. There are many providers out there and what you choose will be completely dependent on your specific requirements so I won’t spend much time evaluating potential solutions, but make sure you have a checklist of your essentials and your nice-to-haves.

Think about pricing, what call features you need, service delivery and uptime, network capacity requirements and SLAs. Are there legal requirements or compliance issues for your organization around managing sensitive customer data that need to be considered? Or do you have a PBX you purchased recently that you’re looking to leverage the investment on?

Conduct thorough research into your chosen provider and make sure that they are the right fit for you from a technology and a functionality point of view - both now, and on their technology roadmap. Think about your potential to make some important transformational change and think about both your short- and long-term objectives.

Preparing for a migration

Although migrations can be simple, this is a relatively big undertaking, so make sure you prepare your business as best as you can for making the change.

Create a thorough checklist for yourself and the wider business that documents your contingency plan for voice network downtime, the measures you will put in place to make it easy for people to work from home, and that your number porting plan is in place.

Pick your migration date and communicate it with your team and the business. Inform your business of what to expect before, during and after the transition and give them any education required if you’re taking the opportunity to deploy new technology.

Measuring success

Although there is an urgent requirement to migrate to IP and SIP, don’t forget that there are opportunities to transform your comms and upgrade your existing practices. Draw up a list of your success metrics and view the migration as the first step on a much longer journey to enhance how you engage with your customers.

Make sure that your employees are happy too. Implement ways and means to collect feedback like regular surveys, because they are the ones on the front line using the technology, their voice is essential to ensure success.

There is a world of opportunities for you to make some substantial enhancements to your customer engagement and communications - you just have to have the right plan in place.

Start planning now

Five years may seem like ages away, but it’s important to start thinking about migration now because failure to migrate to IP telephony ahead of the deadline could result in the loss of voice communications and major disruption to your organization.

Jamie Melling, CEO, Smartnumbers