The ultimate guide to public switched telephone network (PSTN)
Introduction
The UK public switched telephone network (PSTN) has been a reliable workhorse for decades, connecting homes and organisations with a voice service that has evolved over the years.
But like all good things, the PSTN's time is coming to an end. By 2027, this analogue system will be switched off, making way for more advanced digital solutions.
This guide is here to help you understand what the PSTN is, why it's being retired and how your organisation can smoothly transition to a modern alternative. We’ll also share tips on choosing the right digital telephony provider and what to consider during implementation.
- An overview of the UK public switched telephone network
- The benefits and history of the PSTN
- The upcoming analogue switch-off in 2027
- Alternatives to the PSTN
- How to choose and implement a digital telephony solution
- The advantages of working with Virgin Media O₂ Business
Introduction
The UK public switched telephone network (PSTN) has been a reliable workhorse for decades, connecting homes and organisations with a voice service that has evolved over the years.
But like all good things, the PSTN's time is coming to an end. By 2027, this analogue system will be switched off, making way for more advanced digital solutions.
This guide is here to help you understand what the PSTN is, why it's being retired and how your organisation can smoothly transition to a modern alternative. We’ll also share tips on choosing the right digital telephony provider and what to consider during implementation.
- An overview of the UK public switched telephone network
- The benefits and history of the PSTN
- The upcoming analogue switch-off in 2027
- Alternatives to the PSTN
- How to choose and implement a digital telephony solution
- The advantages of working with Virgin Media O₂ Business
What is the UK public switched telephone network?
The UK public switched telephone network (PSTN) is a complex system of copper wires, fibre-optic cables, switching centres and more, all working together to enable voice communication across the country.
It’s what has allowed us to make landline phone calls for decades, connecting homes, businesses and public sector organisations through a vast, interconnected network.
History of the UK PSTN
The PSTN has a long and storied history, beginning in the late 19th century with the first telephone exchanges. Back then, operators manually connected calls by plugging cables into switchboards.
Over time, technology advanced and by the mid-20th century these manual systems were replaced with automated switching equipment.
The UK’s PSTN has continually evolved, moving from analogue to digital exchanges in the 1980s and introducing fibre-optic cables to enhance transmission quality and speed.
Despite these advancements, the core of the system remains rooted in its original analogue technology, which is now showing its age.
How it works
At its most basic, the PSTN works by converting your voice into electrical signals, transmitting them over a network of cables and switches then converting those signals back into sound at the receiving end.
The network is made up of:
Local exchanges
These are the switching centres that connect calls locally and route them to the correct destination.
Transmission lines
These include copper wires and fibre-optic cables that carry voice data between exchanges and to the final destination.
End-user devices
The phones or other communication devices that connect to the PSTN, allowing people to make and receive calls.
When you make a call, your voice is converted into an analogue signal and sent to the nearest exchange. From there, it might be routed through several other exchanges before reaching its destination.
At each step, the signal is boosted to ensure clarity and quality.
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What are the benefits of the UK public
switched telephone network?
The PSTN has been the backbone of UK communications for over a century for good reason. It offers several benefits that have made it indispensable for organisations of all sizes.
Reliability
The PSTN is incredibly stable, with decades of proven performance. It’s built to withstand power outages and other disruptions, making it a dependable choice for voice communication.
Coverage
The PSTN reaches virtually every corner of the UK, providing near-universal access to telephony services. This has been especially important for rural and remote areas where other communication networks may not be as robust.
Simplicity
For many organisations, the PSTN is simple to use and manage. Landline phones are straightforward, with minimal setup and maintenance required.
Quality
While digital technology has caught up in recent years, the PSTN has historically offered high-quality voice communication with minimal latency and interference.
Security
The PSTN’s analogue nature makes it inherently secure, as it’s harder to intercept or tamper with than some digital systems.
The UK public switched telephone network
is being switched off in 2027
The decision to switch off the PSTN is driven by several factors:
- Ageing infrastructure – The PSTN relies on technology that is becoming increasingly difficult and expensive to maintain. Spare parts are scarce and the skills needed to repair and manage the network are becoming harder to find.
- Digital transformation – Organisations are moving towards digital solutions that offer more flexibility, scalability and integration with other services. The PSTN, with its analogue roots, simply can’t keep up with these demands.
- Increased functionality – Modern digital networks offer features that the PSTN cannot, such as video conferencing, unified communications and enhanced security. These features are essential for today’s businesses and organisations.
- Efficiency – Digital networks are more efficient to operate, requiring less power and offering higher capacity. This not only reduces costs but also supports the UK’s sustainability goals.
The switch-off of the PSTN will have varying impacts depending on the size and nature of your organisation.
- Small and medium businesses (SMBs) – For SMBs, the switch-off might be a wake-up call to modernise communications infrastructure. While the transition may involve upfront costs, the long-term benefits of moving to a digital system – such as improved functionality and reduced operational costs – can be substantial.
- Large businesses – Larger organisations often have more complex communication needs, including integration with customer relationship management (CRM) systems, call centres and other digital services. The analogue switch-off offers an opportunity to streamline these systems, reduce redundancy and future-proof communications.
- Public sector organisations – Public sector bodies, like hospitals and local councils, rely on the PSTN for mission-critical services. Analogue switch-off means these organisations will need to carefully plan their transition to ensure no disruption to essential services. However, the move to digital can also enable better service delivery, improved data management and cost savings.
Voice over internet protocol (VoIP)
VoIP is one of the most popular alternatives to the PSTN. It works by converting voice signals into digital data and transmitting them over the internet. VoIP offers many advantages including:
Cost savings
VoIP can significantly reduce phone bills, especially for international calls.
More flexibility
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More impact
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Session initiation protocol (SIP) trunking
SIP trunking is a method of delivering voice and other communication services over the internet, using the same technology as VoIP but with additional capabilities.
It’s a great option for organisations looking to maintain some of their existing telephony infrastructure while moving to a digital system. Benefits include:
Improved reliability
SIP trunks offer redundancy and failover options, ensuring calls are routed even if one path fails.
Unified communications
SIP can integrate voice, video and data into a single service, streamlining communication and reducing costs.
Enhanced features
SIP supports advanced features like call forwarding, auto attendants and voicemail-to-email.
Integrated services digital network (ISDN) alternatives
ISDN has been a go-to for digital communication in the past, but with its own switch-off looming, alternatives like VoIP and SIP trunking are the way forward.
However, some organisations may consider moving to fibre-based services like FTTP (fibre to the premises) to support high-quality digital voice and data.
Mobile networks
For some organisations, mobile networks offer a viable alternative to traditional landlines.
With advancements in 4G and 5G, mobile voice services can be just as reliable and offer the added benefit of mobility. This is particularly useful for businesses with a mobile workforce or those in areas where fixed-line infrastructure is lacking.
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What to consider when choosing a digital telephony solution and provider
Scalability
Your telephony solution should be able to grow with your organisation. Look for a system that can easily add new users, lines and features as needed, without requiring significant infrastructure changes.
Integration
Modern digital telephony solutions should integrate seamlessly with your existing systems, whether that’s CRM software, email or other communication tools. This will ensure a smooth transition and improve efficiency across your organisation.
Cost
While cost shouldn’t be the only factor, it’s important to understand the total cost of ownership. Consider not just the upfront costs but also ongoing fees, maintenance and potential savings from reduced operational costs.
Security
As with any digital service, security is paramount. Ensure the provider offers robust encryption, secure data centres and compliance with relevant regulations to protect your sensitive data.
Support
Consider the level of support you’ll receive from your provider. This includes not just technical support but also help with setup, training and ongoing maintenance.
A provider that offers comprehensive support can make a big difference to the success of your transition.
Flexibility
Your organisation’s needs may change over time, so choose a provider that offers flexible contract terms and the ability to adapt the service as required.
This could include adding new features, adjusting capacity or even changing service models.
What to watch out
for in a digital
telephony provider
Hidden costs
Some providers may offer low initial prices but tack on extra charges for things like set up, maintenance or additional features. Make sure you get a clear understanding of all potential costs up front.
Poor customer service
Reliable support is crucial, especially during the transition phase. Check reviews, ask for references and consider how responsive and helpful the provider is during your initial enquiries.
Limited scalability
A provider that can’t scale with your organisation’s needs could become a bottleneck in the future.
Ensure the solution can grow as your organisation does, without requiring a complete overhaul.
Lack of integration options
If a provider’s system doesn’t integrate well with your existing tools and software, it could lead to inefficiencies and frustrations.
Look for a solution that’s designed to work seamlessly with your current infrastructure.
Security weaknesses
With cyber threats on the rise, you can’t afford to compromise on security.
Ensure the provider offers strong encryption, secure authentication and complies with data protection regulations relevant to your industry.
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In a nutshell
The UK public switched telephone network has served us well, but its days are numbered.
As we approach the analogue switch-off in 2027, it’s crucial to start planning your transition to a digital telephony solution.
By understanding the benefits and challenges, and by carefully selecting the right provider, your organisation can enjoy a seamless transition and reap the rewards of modern communication technology.
Why choose Virgin Media O2 Business?
When it comes to making the switch, we’re here to help with a range of digital telephony solutions designed to meet the needs of organisations of all sizes, including Webex, 8x8 and Microsoft Teams Voice.
With our robust infrastructure, extensive experience and commitment to customer service, we’re the perfect partner to guide you through this transition.
Whether you need a scalable VoIP solution, cloud collaboration tools or a fully integrated communications system, we have the expertise and technology to make it happen.
Ready to explore how a new digital telephony
solution can benefit your organisation?
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