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What BT's PSTN Network Switch Off Means for your Security Systems

Find out what it is and how your security or fire alarm system may be affected in our blog . 
Scissors Phone

The Background

BT are moving all customers from the old analogue public switched telephone network (PSTN) to a fully digital network. They have already started & plan to have moved everyone over before Openreach stop the PSTN (and ISDN) service in 2025. By then, every phone line in the UK will be digital, routing calls over IP (Internet Protocol) rather than the traditional PSTN.

This blog has been written to explain the background to this change and how it may impact your security systems. .

What does switching it off actually mean? 

This will affect business and home. And it’s not just your phone services you need to think about. It’s everything else that currently uses the old phone network, all your non-voice services connected to PSTN or ISDN lines. Things like alarms, EPOS machines, door entry systems, CCTV, and faxes.

BT plans to complete the closure by 2025 of this network in favour of a digital network. 

The PSTN will be closed in phases. Some analogue network exchanges have already been closed as part of a trial and then a stop sell phase will begin. 

This means that no more new services or devices will be connected to the old analogue network – which isn’t a problem if you’re installing a new system - most modern security solutions are digital anyway. 

The stop-sell phase will also be gradually rolled out based on clusters of network exchanges. To find out when your local exchange will be affected, you should speak to your security provider.  

After the stop-sell phase, the entire network will finally be shut-down for good. This means that any devices still connected to the analogue network will no longer be able to communicate. 

This is where the biggest risk occurs where your fire safety and security may be concerned. 

If your business security systems, including fire alarms and intruder alarms, rely on the analogue network, the signaling method & probably signaling hardware will need to be replaced or updated before the cut-off point.

What do I need to do to ensure my business remains protected? 

Working with the maintainer of your fire and security systems, you should organise a check to determine whether your current fire alarm or security systems signaling equipment rely on digital or analogue communication. 

It’s a good idea to contact your security provider as soon as possible, they’ll be able to confirm it for you and explain any necessary next steps that you may need to take.  

There’s a good chance your system is digital if it has been installed in the last five years, but it is always best to make sure to remove any doubt. 

If your system is already utilising digital signaling, then you’re likely to be already prepared for the PSTN switch-off and won’t need to take action. .

If your fire alarm or security does still rely on the analogue network for either single or one path of a dual path signal, then you need to take action. 

(1.) Reconfigure your existing signaling

It is possible but unlikely that your existing signaling equipment can be reconfigured to use IP / Mobile phone 3G / 4G / 5G signal - your integrator will be able to confirm this.

(2.) Upgrade your existing system

It is likely that your signaling unit will need to be replaced with a new unit capable of utilising  IP / Mobile phone 3G / 4G / 5G signal - your integrator will be able to confirm this.

It is likely that your existing unit will be able to utilise the newer signaling equipment, however it is recommended that this is confirmed by your integrator.

There may be some very old systems out there that will need replacing wholesale before the newer signaling unit can be utilised correctly.

What if I don’t act? 

Put simply, there is likely to be a huge rush before the 2025 cut off and leaving a review too late may mean that there is insufficient time to make the necessary changes. 

If you take no action or leave it too late, you could be left with an alarm system that does not communicate off site. 

This could mean you are in breach of insurance regulations and at risk of a delayed or no response to an activation.

What should you do now? 

Speak to your alarm system maintainer and make sure you are clear how your systems will be impacted and what your options are.