Openreach's proposal is to switch off the old analogue network (the PSTN) in 2025

What is the BIG Switch Off?

As of the 5th September 2023, BT Openreach launched a nationwide stop-sell of the Public Switched Telephone Network (PSTN), signaling a major step towards modernizing communication technologies. This marked the beginning of a phased approach towards the complete shutdown of the PSTN, scheduled for December 2025.

With the stop-sell in place, BT Openreach ceased the provision of new PSTN-based services effective from 5th September 2023. It’s important to note that existing legacy PSTN services can still be used until the full switch-off in December 2025. However, during this period, it will not be possible to purchase new ISDN or PSTN-related services or make modifications to existing ones.

What options you have before the BIG Switch Off?

When the PSTN network fades away, the only option for UK businesses and residentials customers will be to make the switch to VoIP telephony, which harnesses the power of active internet connections like never before.

And who better to guide you through this transformation than Airbytes? We’ll seamlessly transition your communication system to VoIP, ensuring uninterrupted connectivity, free porting and improved efficiency.


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PSTN and ISDN switching off in 2025

What is PSTN?

PSTN stands for Public Switched Telephone Network. The PSTN is the traditional telephone network that has been in use for many decades and is still in widespread use today. It is based on a circuit-switched architecture, which means that a dedicated connection is established between two or more parties for the duration of a call or other communication.

What is an ISDN line?

ISDN stands for Integrated Services Digital Network. It is a type of digital telephone line that is used to transmit voice and data over the same line. ISDN lines are often used by businesses and other organizations to provide high-quality, reliable telephone and data services. One of the main benefits of ISDN is that it allows multiple channels to be transmitted over a single line, which means that multiple calls or data connections can be made at the same time. This makes it possible for businesses to have multiple phone lines and internet connections without having to install multiple physical lines. ISDN lines also provide higher quality audio and video transmission than traditional PSTN lines, which makes them well-suited for applications such as videoconferencing.

In 1986, BT introduced ISDN in the UK.

What will replace ISDN?

There are two options that will replace ISDN, VoIP and SIP.

What is VoIP?

VoIP stands for Voice over Internet Protocol. It refers to a type of technology that allows voice communication to be transmitted over the internet or other IP-based networks. With VoIP, telephone calls are made over the internet rather than through the traditional PSTN (Public Switched Telephone Network). This can be done using a variety of devices, including computers, smartphones, and dedicated VoIP phones.

One of the main benefits of VoIP is that it can be much less expensive than traditional telephone services, especially for international calls. VoIP calls can also be made over the internet from anywhere with a stable internet connection, which makes it possible to make and receive calls while on the go. In addition, VoIP technology can be easily integrated with other communication and collaboration tools, such as instant messaging, video conferencing, and screen sharing.

What is SIP?

SIP stands for Session Initiation Protocol. It is a signaling protocol that is used to initiate, modify, and terminate multimedia sessions such as voice and video calls over the internet. SIP is used in a wide variety of applications, including VoIP (Voice over Internet Protocol) and other types of internet telephony, as well as video conferencing, instant messaging, and other types of real-time communication.

SIP works by establishing a connection between two or more devices, such as computers or smartphones, and negotiating the parameters of the session (e.g., the codec to be used, the format of the media, etc.). Once the session has been established, SIP can be used to control the session, including adding or removing participants, adjusting the quality of the media, and terminating the session when it is no longer needed. SIP is a widely used protocol that is supported by a wide range of devices and software applications, and it is an important part of many modern communication systems.