ISDN to SIP - What's really happening?

ISDN to SIP - What's really happening?

Sunday, April 5, 2020

It may be news to you, or you may have already heard, traditional analogue telephone networks have been scheduled to be switched off in 2025. Luckily, we are here to let you know what it means and how it affects you.

What is ISDN?

You may have heard that BT have confirmed to switch off heritage phone lines. But what really are they? ISDN stands for Integrated Services Digital Network – if that doesn’t mean much to you – it’s the copper wires in the ground that were the first used to connect calls.

Why is BT switching it off?

There are many reasons why BT are switching off traditional copper lines from 2025. The main reason is that the infrastructure simply does not have the capacity to meet the demand anymore. There are many restrictions with ISDN, including a restricted number of calls being able to be made and received at the same time, plus you have to have a separate line to access the internet.

Quite simply, there is better technology available now.

Why does it matter to you?

If you use a phone that runs on an ISDN line, the line will be switched off in 2025. So you need to start looking for an alternative.

What’s the alternative?

The alternative is SIP trunking, this uses the internet to stream media and make phone calls. Effectively, SIP uses the internet to make calls rather than a physical wire in the ground. It uses your circuit that connects your phone to the internet to make calls. It really is as simple as that.

The best part is, most newer phones that run on ISDN lines can be switched over to SIP trunking either straight away, or you may need to buy a card to allow the switch. Of course, in order to reap the best benefits included with SIP trunking, you may need a new handset.

Speak to us to find out how we can help you to prepare for 2025, it’s never too early to start planning!

For more information on what eve can do for your business visit their website at or call us.


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