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Ringing in the Past: Fascinating Facts About the PSTN

The Public Switched Telephone Network (PSTN) is the backbone of the traditional phone system, connecting billions of people worldwide for over a century. While we often take it for granted, the PSTN holds a treasure trove of intriguing facts and history. In this post, we’ll delve into some captivating and lesser-known facts about the PSTN.

  1. The Birth of the PSTN: The PSTN was born in 1876 when Alexander Graham Bell made the first successful telephone call to his assistant, Thomas Watson, with the famous words, “Mr. Watson, come here, I want to see you.” This call marked the dawn of the telephone era and the establishment of the world’s first telephone exchange in New Haven, Connecticut.
  2. Manual Switchboards: Early telephone exchanges relied on manual switchboard operators who physically connected calls by plugging and unplugging cords. These operators were primarily women and became known as “Hello Girls.”
  3. Rotary Dial Phones: The first rotary dial telephone, which allowed users to directly dial numbers rather than rely on operators, was introduced in the early 20th century. Rotary dial phones became a household staple for many decades.
  4. Area Codes: The concept of area codes was introduced in 1947 as part of the North American Numbering Plan (NANP). The three-digit area codes were designed to efficiently route calls across large geographic areas.
  5. The Demise of Party Lines: In the early days of the PSTN, party lines were common. Multiple households shared a single telephone line, and users could listen in on each other’s conversations. The advent of private lines gradually phased out this practice.
  6. Touch-Tone Phones: The push-button or touch-tone phone, introduced in the 1960s, replaced the rotary dial. These phones allowed for faster and more accurate dialing and became the standard for decades.
  7. The Red Phone: The “red phone” is a term often associated with a direct communication link between the leaders of the United States and the Soviet Union during the Cold War. While such a phone existed, it was not a single red phone but rather a secure communication network.
  8. Voice over PSTN: The PSTN originally carried only voice calls. However, it evolved to support data transmission, enabling services like fax machines and early modems.
  9. The Internet’s Impact: The rise of the internet and digital communication technologies has transformed the telecommunications landscape. Voice over Internet Protocol (VoIP) and mobile networks have challenged the dominance of traditional PSTN systems.
  10. Continued Evolution: While the PSTN has seen significant changes over the years, it is not yet a relic of the past. Many countries are transitioning to IP-based networks, but the PSTN remains a critical part of global telecommunications infrastructure.
  11. Emergency Services: The PSTN has played a crucial role in connecting people to emergency services. Dialing “911” in the United States or “999” in the UK connects callers to immediate help.
  12. Global Reach: The PSTN connects people across vast distances, facilitating communication and business transactions around the world. It has enabled international trade and diplomacy on an unprecedented scale.

The history of the PSTN is a remarkable journey through the evolution of communication. From Bell’s first words over a wire to the digital age, the PSTN has played a pivotal role in connecting people globally. While it faces new challenges in the era of digital technology, it remains an essential part of our interconnected world, reminding us of the incredible progress we’ve made in telecommunications. The next time you pick up a phone, take a moment to appreciate the rich history and innovation behind the dial tone.

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ISDN Withdrawal – the key questions answered

In this article we answer some of the key questions you may have about the upcoming ISDN withdrawal and the wider closing of the PSTN.

What is the PSTN?

The Public Switched Telephone network or PSTN currently forms a large part of the UK telecoms infrastructure. It is made up of copper telephone lines, fibre optic cables, microwave transmission links, satellites, undersea telephone cables and mobile networks. It used for several functions, including the making of calls using analogue voice data and Supporting digital services such as ISDN.

Why is the PSTN being withdrawn?

According to Openreach:

‘the equipment which runs the PSTN is ageing and will reach its end of life by December 2025.  This means the analogue telephone voice services that are reliant on this network will no longer be available……. Spare parts are becoming out of manufacture and, additionally, many of the people who designed, built and operated the system are retired or close to retirement so skills are increasingly scarce.’

The current PSTN network will be replaced with a fibre and VoIP network.

What products will be affected?

The PSTN network currently supports a number of products which, when it is withdrawn, will no longer be available. The key one which will affect business customers is the Integrated Services Digital Network (ISDN). Many companies have telephony systems which use either ISDN2 or ISDN30 channels to make and receive calls. Over 16 million lines and channels are affected by the swicth off and will need migrating prior to 2025.

When are the services being withdrawn?

Openreach plans to stop allowing the connection of new PSTN services, like ISDN, from September 2023. All connections will be finally switched off in December of 2025.

How will the switch off be managed?

This is still an ongoing discussion. Openreach are in regular discussion with Ofcom and the Office of the Telecommunications Adjudicator (OTA2) about this process. The Federation of Communication Services (FCS) is also involved in these discussions. As a member of the FCS, Deep Blue is part of the wider conversation about how the withdrawal will be managed for communications providers and their customers.

What alternative products will there be?

Openreach are currently in the process of introducing a range of new services alongside some of their existing ones to ensure internet access is available once the PSTN is discontinued. From there, call traffic will be handled as Voice over IP (VoIP). This basically means that your voice call is sent as bits of data via your internet connection. If you are using SIP trunks, Horizon or InBound then you are already making calls via this technology.

I’m using ISDN lines, should I make the switch now?

As always when big changes are happening, some companies use the uncertainty for their own gains. We have already seen customers who have received communications, both at their business and at home, implying their connectivity is under threat and they should move now before it’s too late! This, luckily, is not true. There is still almost five and a half years until the PSTN is deactivated so while it is something to start giving thought to, it is not a reason to rush to make changes.

There are, however, plenty of other good reasons to make the switch. Keep a look out for our article ‘ISDN to VoIP- is it time to make the change?’ coming soon. In it we will detail the many benefits of switching to a VoIP solution: like potential cost savings, resilience and features.

In Conclusion

Many companies are already taking advantage of digital services which will serve them now and after the switch off. For those that aren’t, there is plenty of time and plenty of options for them to make the move to. Openreach, the FCS and service providers like Deep Blue are all working closely to put plans and procedures in place to manage the switch.

Deep Blue customers can rest assured that we will be on hand to make the change as easy and stress free as possible.

Have more questions, want to get ahead of the crowd or keen to start taking advantage of VoIP for it’s many other benefits? Contact Deep Blue today on 0333 240 9100 or by email to theteam@deepbluetelecom.co.uk