March 11th 2020 


Recent research by Censuswide shows that 25% of businesses in the UK are still unaware of the ISDN switch off that is coming in 2025.

What is the ISDN shutdown?

BT are set to switch off ISDN and PSTN by 2025 and are going to move their whole network over to SIP. The current ISDN setup is deemed as outdated and in need of newer technology, just as analogue TV was switched off several years ago.

Everyone in the UK using ISDN will be affected, which is a lot of people. Before we go over what is going to replace ISDN, let's go through what it is and why it is 'failing'.

ISDN, standing for 'Integrated Services Digital Network' are phone lines that allow the transmission of digital data (voice) over the PSTN (Public Switched Telephone Network). They were introduced in 1986 and were commonly used before the introduction of VoIP and SIP Trunking. ISDN itself isn't failing, and even today lots of businesses are using ISDN without problems. But, like all technology, someday it becomes obsolete and requires replacing. 

What is VoIP?

VoIP (Voice over Internet Protocol) is a technology that allows you to use your internet to make voice calls, rather than through PSTN lines that a 'traditional' phone system would do.

What is SIP Trunking?

SIP 'Session Initiation Protocol' allows you to send multimedia (voice, instant messaging, video calls etc.) using the internet. Please watch our video on SIP Trunks for more information.

Where do you go from here?

Join the switchover movement – many businesses have already future proofed their infrastructure by moving to SIP.

There are a lot of benefits to SIP trunks from lower costs, higher quality and reliability through to disaster recovery and more!

Contact us today to find out how we can help your business make the move from ISDN and PSTN to SIP. 

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