Time is running out. Get ahead
of the big PSTN switch off in 2027



BT Group has announced an extension of the deadline to transition from the old analogue PSTN lines to full fibre broadband. The new deadline is now the end of January 2027. This extension is aimed at ensuring that vulnerable customers, including telecare users, have ample time to make the necessary arrangements without disruption. BT Group is also encouraging all customers, especially public sector organisations and those relying on telecare services, to engage early in the migration process. This move is a crucial step to accommodate the needs of those who rely heavily on existing systems while updating the infrastructure to more reliable digital services. We at CDS are here to assist you through these changes and to ensure that your transition is as smooth and efficient as possible.


What is PSTN?

The Public Switched Telephone Network (PSTN) has been a cornerstone of global communication since its inception in the late 1800s and is an extensive network, often referred to as the traditional circuit-switched telephone network, and has been the backbone of telecommunication for over a century. Comprising local, national, and international carriers, PSTN has facilitated a robust infrastructure that has supported voice-oriented communications worldwide.

How do PSTN lines work?

The Public Switched Telephone Network (PSTN) operates through an intricate infrastructure that combines various forms of communication technologies, including telephone lines, fibre optic cables, switching centres, cellular networks, satellites, and cable systems. This comprehensive mesh allows users around the world to make landline telephone calls to one another, serving as a fundamental network for voice communication.

Here’s a step-by-step explanation of how PSTN works:

  • Initiating a Call: When a call is made from a landline telephone, the signal is transmitted from the caller’s handset through the local loop (the physical wire connection) to the local exchange.
  • Switching: The local exchange, equipped with network switches, acts as a node. These switches are responsible for routing the call through the network. Depending on the distance and the network architecture, the call may pass through several intermediate switches or central offices before reaching the destination.
  • Routing the Call: Each switch within the PSTN determines the most efficient path the call should take to reach the receiving end. This routing is dynamic and can change based on network traffic, outages, or other factors affecting the communication line.
  • Reaching the Recipient: Once the call reaches the local exchange nearest to the recipient, it is directed through the local loop to the recipient’s phone.
  • Transmission Mediums: The voice signals can travel over various mediums along their journey. While traditional PSTN largely used copper wires, modern improvements have incorporated more fibre optic cables, which offer higher bandwidth and better resistance to electromagnetic interference.
  • Dial-Up Internet: Historically, PSTN lines were also used for internet connectivity via dial-up modems. These devices modulate digital data from computers into analog signals compatible with the telephone network and vice versa. Dial-up connections are capable of supporting speeds up to 56 Kbps, which were sufficient in the early days of the internet but are now vastly outperformed by broadband technologies.

With the advent of broadband internet, the use of PSTN for data transmission has significantly declined, as broadband provides faster, more reliable internet access without the need for dial-up’s continuous connection setup and disconnection processes.

The transition to digital technologies like VoIP and dedicated data networks reflects the evolving needs for faster, more efficient, and higher capacity communication systems, signalling a gradual phase-out of traditional PSTN infrastructures in favour of more modern solutions.


Why are we switching to VoIP?

The distinction between the Public Switched Telephone Network (PSTN) and Voice over Internet Protocol (VoIP) primarily lies in their technological approach and infrastructure for transmitting voice communications. Here’s a detailed comparison to highlight their differences:

1. Technology and Infrastructure

  • PSTN: This is the traditional telephone system that relies on circuit-switched networks to make voice calls. It uses a network of physical lines (copper wires and fiber optic cables) and switching centers to establish a dedicated circuit between two points for the duration of a call.
  • VoIP: In contrast, VoIP transmits voice communications over the internet or other packet-switched networks. Instead of establishing a dedicated circuit, VoIP converts voice into digital packets, which are then transmitted over the network and reassembled into sound at the other end.

2. Transmission Method

  • PSTN: Operates on a circuit-switched model where a physical path is established and maintained throughout the duration of a call.
  • VoIP: Uses a packet-switched model where voice data is sent in small packets that can take different paths to the destination and do not require a single dedicated path.

3. Cost and Maintenance

  • PSTN: Generally incurs higher costs due to maintenance of physical infrastructure and regulated pricing structures. Long-distance calls can be especially expensive due to the infrastructure and tariffs involved.
  • VoIP: Offers lower costs, particularly for long-distance and international calls, as it uses existing internet or network infrastructure. There are minimal incremental costs over the internet usage, and many service providers offer flat rates for unlimited calls.

4. Scalability and Flexibility

  • PSTN: Scaling up typically requires physical installation of new lines and hardware, which can be time-consuming and costly.
  • VoIP: Highly scalable and flexible, as adding lines or extensions often only requires software configuration. This can be quickly done without the need for physical installations.

5. Features and Integration

  • PSTN: Provides basic voice calling features and some additional services like caller ID, voicemail, and call forwarding.
  • VoIP: Supports a wide range of features beyond traditional voice services, including video calls, text messaging, and integration with various digital communication platforms. VoIP can integrate with email, web browsers, and real-time communication services, facilitating features like voicemail to email, call analytics, and unified communications.

6. Reliability and Quality

  • PSTN: Known for high reliability and consistent call quality as it uses established, dedicated circuits for each call.
  • VoIP: While it offers greater flexibility and features, its call quality and reliability can be dependent on internet bandwidth and network stability. Quality of Service (QoS) configurations are essential to prioritize voice traffic over other types of internet traffic to maintain call quality.

7. Evolution and Future Outlook

  • PSTN: As technology progresses, PSTN is gradually being phased out or integrated into newer digital networks due to its limitations in supporting modern communication needs.
  • VoIP: Continues to evolve with advancements in internet technologies and is increasingly becoming the standard for business and personal communications globally.

Understanding these differences helps in determining the appropriate technology for communication needs, especially for businesses considering infrastructure investments and upgrades. VoIP often represents a more modern, cost-effective, and feature-rich option compared to traditional PSTN systems.


Choosing APS for the transition

As the UK progresses towards a fully digital communication system by December 2025, the switch from the analogue Public Switched Telephone Network (PSTN) to an all IP (Internet Protocol) network, including Voice Over Internet Protocol (VoIP), is inevitable. This transition promises enhanced performance, integration capabilities, and more robust security features that are essential in our fast-paced, data-driven world.

For businesses and individuals relying on security systems such as CCTV, access control, and intruder alarms, this switch to IP technology means an upgrade in security protocols through encrypted data transfers. This is crucial for Alarm Receiving Centres (ARCs) that monitor these devices, providing a higher level of protection against potential breaches.

The switch also has significant implications for the telecare industry and individuals dependent on personal alarms. With the all IP network fully operational by 2025, it’s imperative to start preparing now. Transitioning early will ensure that systems are compatible with the new technology, thereby maintaining the safety and security of the most vulnerable.

At APS, we understand the importance of staying ahead in technological advancements to ensure seamless and secure operations for all our clients. This digital switchover is just one aspect of our comprehensive range of services designed to protect and enhance your business and personal environments. From advanced cybersecurity solutions to integrated building management systems, our offerings are tailored to meet diverse needs, ensuring peace of mind in a digital age.

Businesses, too, need to act swiftly. The shift to digital solutions isn’t just about upgrading existing systems but also about seizing the opportunity to leverage new, advanced digital products that can scale according to business needs. Delaying the transition could lead to operational disruptions and increased difficulties in managing communication systems effectively.

Our team is dedicated to guiding you through this digital switchover. We are equipped to discuss what these changes entail and assist in planning your next steps, ensuring your communication systems are not only compatible with the new IP technology but are also optimised to protect your most valuable assets across Nottinghamshire, Derbyshire, and Leicestershire.

Stay connected, stay protected. Contact us to explore our full range of services and reach out to our specialist team for a consultation on how to best navigate this transition and harness the full potential of digital communications for your business.

Simply reach out to us to discover how we can assist during during your PSTN transition along with our other services that keep you safe and compliant.

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