ISDN: The end of the traditional telephone network

- and why it concerns you!

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One of the most popular forms of business communications, ISDN, is about to be shut off for good as it has recently been deemed obsolete by giant BT Openreach, the country’s national broadband infrastructure provider, and it will likely affect you and your business.

We are going to take a look at what this old technology is, what to expect when it is shut off, the alternatives available, the benefits of those alternatives, and why you need to focus on making the switch before it’s too late.

ISDN – International Services Digital Network

ISDN, first defined in 1988, is a set of standards (or rules) for simultaneously digitally broadcasting mainly voice, video, and data over the PSTN or Public Switched Telephone Network. The PSTN is an aggregation of the national and local telephone networks. These national and local networks are all interconnected with the PSTN so that they may all communicate with each other.

ISDN and PSTN, simply put, allow you to not only talk on the phone with someone 1 km or 1000 km away, but they also allow you to access the internet at broadband speeds all from the same port.

Why is BT switching off ISDN?

As mentioned above, ISDN was first defined in 1988, however, BT Openreach introduced it in 1986. As you know, technology is growing at a seemingly endless rate, and it is beyond amazing for technology of any form to last over 3 decades like ISDN has.

It goes without saying that technology over the last 30+ years has obviously improved greatly. Recently, BT has been investing a lot in newer and more advanced technology that they have deemed their “Fibre-First” operation. At the beginning of this year they announced plans to have 3 million premises connected by ultra-fast fibre by 2020.

VoIP and SIP – the best alternatives

With BT pushing their new “Fibre-first” campaign and with investments in the UK’s communications infrastructure being plentiful, access to these fibre networks are quick and inexpensive for small businesses to use IP-based solutions such as VoIP and SIP.

VoIP is a cloud-based telephony solution. Your entire phone system will be moved online so that all of your calls are sent and received over an internet connection. This is not as complicated as it sounds, and has many benefits – far beyond what the old ISDN technology offers.

VoIP benefits

  • Receiving Voicemails through Email
  • Call Recording (with numerous options)
  • Easy Disaster Recovery Process
  • Call Queueing
  • Call Analytics & Data Tracking
  • Access Systems On Multiple Devices (Tablet, Laptop, etc…)

SIP is a way to use your current phone setup to connect to the world in a different way. A business’s phones and PBX system will be connected to public networks by means of the internet. This removes the need for a business to have a (now deemed obsolete) ISDN line. This technology allows you to keep your same phone number, keep the same number of phone lines, and keep your company’s equipment in-tact.

SIP benefits

  • Manage everything from a central location
  • Scale and grow without worries
  • Emergency? No problem. Easily divert to a backup system.
  • Significant financial savings from monthly phone charges

Change is good and necessary

Adapting to new technology is essential for a business to grow these days. Sure, ISDN will not be switched off until 2025. But that doesn’t mean you should wait. There are numerous reasons why you should make the necessary changes now. Regardless of the fate that ISDN is facing.

  • Financial Savings – New fibre technology is plentiful making access to it much less expensive. You can save money by utilizing this extremely fast broadband to handle the way you make and receive phone calls.
  • Greater Control – You can organize and manage everything from one central location. This gives you extra time to focus on the core components of your business.
  • Redundancy – Gone are the days when “the phone lines are down”. This technology allows for the installation of multiple lines as backups in the event of an issue.
  • Analytics and ROI – The analytics and data available from your calls can increase the ROI on any marketing campaign. You can see where calls are coming from, conversion rates, and market better to your target demographics
  • Fast Installation – You are not waiting for someone from the phone company to come and physically install separate phone lines. Need a new line for a new employee? Have one in minutes with a quick phone call.


Switch today

A fast and painless installation, up to 50% saved on monthly bills, greater control, access to raw data, and an increased up-time. It’s a no-brainer why BT is shutting off ISDN in a few years. The alternatives already speak for themselves.

Windsor Telecom is the #1 provider of UK business numbers. Contact us today to speak with a specialist about switching to VoIP or SIP so you can reap the benefits of better technology.