All you Need to Know About UK ISDN Switch off | Xinix

Integrated Services Digital Network (ISDN), a digital telecommunications standard that was developed to provide a higher quality of voice and data transmission over traditional analog phone lines is being switched off. Legacy landlines have served the telecommunication world for decades. However, these are no longer compatible enough for today’s digitally-driven era. Not only this, the high cost of maintaining PSTN/ISDN infrastructure and the attractive convenience offered by digital alternatives are more reasons to switch to better choices.

By the year 2025, ISDN will be turned off indefinitely. With the timeline getting closer, it’s important to understand and shift to digital & 5G Technology choices so as to streamline your business communications and to future proof your company.

What is ISDN?

ISDN stands for Integrated Services Digital Network (ISDN). This is capable of transmitting voice, data, video and other network services via Public Switched Telephone Network (PTSN).

Born out of necessity to facilitate long-distance connections, ISDN technology was introduced in 1985. Since then, it has been widely used for reliable data transmission with a speed of up to 128 Kbps; faster than the conventional analogue phones. Furthermore, ISDN supports additional useful features including call waiting, caller ID, and three-way calling.

ISDN switch off or WRL withdrawal

The Public Switched Telephone Network (PSTN) supports a number of Openreach products that are collectively known as ‘Wholesale Line Rental’ (WLR) products. These include WLR3 analogue, ISDN 2 and ISDN 30, Narrowband Line Share, Local Loop Unbundling Shared Metallic Path Facilities (LLU SMPF) and few more. Most of the businesses rely on these products for voice communications systems. ISDN switch off means that these products will no longer be available for business communications. Therefore, the term WRL withdrawal and ISDN switch off are sometimes used interchangeably.

Reasons for ISDN switch off

Over the course of time, the technology has served well for faster and reliable communication and data transmission. The question is why is it being switched off? The answer is simply that these are old and outdated. These copper-based public switched telephone networks (PSTN) and ISDN can no longer meet the demands of the digital marketplace. The technology is too obsolete to be able to handle and deliver the required volume or quality of data in today’s digitally-driven and hyper-connected worlds.

Furthermore, the copper-based PSTN lines operate on huge physical infrastructure which cost millions in maintenance every single year. Many of the necessary spare parts of infrastructure are no longer being manufactured. One of the manufacturer commented;

“many of the people who designed, built and operated the system are retired or close to retirement so skills are increasingly scarce.”

Truth be told, investing on this aging, unreliable technology is not a wise choice when it is clearly no longer serving the purpose.

Timeline for ISDN phase out 

  • Year 2017 – BT announced the intention to phase out PSTN and ISDN by 2025 
  • Year 2018 -Openreach started to improve fiber fast strategy in order to introduce new technologies that are easily accessible to all 
  • Year 2020 – Five year reminded by BT to withdraw WLR and to be replaced by Single Order Generic Ethernet Access (SoGea) technology to bypass the need of conventional PSTN 
  • Year 2023 – BT has announced a national WLR stop sell rollout in September 2023. By now, BT has stopped selling new ISDN lines and in a number of trial areas. As the timeline is approaching, the number of ‘stop sell’ trial areas is increasing. In September 2023, there will be 648 different exchanges in the UK that will no longer be operational. It means businesses in those areas must opt for digital choices at earliest.
  • December 2025 – Complete phase out of old PSTN and ISDN technology 

What are the alternatives of ISDN?

This outdated technology is rapidly being replaced by advanced digital technologies, such as digital phone lines, internet-based or hosted VoIP phone systems. These are capable of routing calls using IP technology that enables data transmission via the internet. Thus, these digital alternatives offer advanced features, added flexibility, convenience and affordability for both business and domestic use. Here are some of alternative options for ISDN phase out:

IP phone system 

based on Internet Protocol (IP) technology. An Ethernet connection either on Wide Area Network (WAN) or a Local Area Network (LAN) connects the handsets.

SIP and SIP trunks 

Session initiation protocol (SIP) is of the protocols of VoIP technology. This is an on-premise or hosted solution for a telephone system that will use virtual landline instead of conventional physical infrastructure. 

Hybrid Phone System 

This system is a combination of different technologies including ISDN, IP and analogue phone system.

Hosted Phone system / Hosted PBX

This is a cloud-based phone system that requires internet connection (IP technology). Here you are renting the phone system rather than purchasing your own dedicated connection.

Read More: Navigating the Switch from Legacy Landline Phones by 2025

Embracing the digital future of business telephony 

As the ISDN switch off is getting closer, businesses in the UK are shifting to cloud based telephony or VoIP phone systems. The market analysis suggests that UK VoIP has a compound annual growth rate (CAGR) of 9.08%. According to reports of Global Market Insight, by the year 2025, the VoIP market may reach a staggering $55 billion.

The cloud based telephony is feature-rich technology that is flexible, scalable, quicker to install and affordable as well. 

More than 3 billion people use mobile VoIP services worldwide. Survey suggests that there is 30-40% cost saving with VoIP. With cloud based telephony, businesses have reporte about 67% enhanced productivity. Similarly, startups have reported a huge 90% cost saving when using VoIP systems. In short, digital telephony has a promising future for both businesses and domestic use.

What to expect with ISDN switch off or WLR withdrawal

BT PSTN supports WLR, ISDN2 and ISDN30, Narrowband Line Share, Local Loop Unbundling Shared Metallic Path Facilities (LLU SMPF), and a few more products. These products will no longer be functional after PSTN and ISDN switch off in 2025. Apart from the communication system, this phase out will also impact non-voice services such as CCTV, Alarms, Faxes, EPOS machines and door entry systems.

Undoubtedly, this is going to be the biggest shake up to telecommunications for more than 30 years. As per a survey, less than one in ten businesses is prepared for this huge transition. Not shifting to VoIP-based systems in time, will leave them with poor communication systems, added cost, missed opportunities and subsequent loss.

Despite the looming switch off, about 69.5 percent of businesses are still using legacy phone systems. It is crucial for businesses to adapt IP technology to create a fully digital communication system, replacing all legacy networks.

Businesses should be well prepared ahead of ISDN switch off

Although the switch off date is coming closer, there is still time for businesses to be prepared for the future. BT has stopped taking new ISDN orders. Thus, businesses should consider upgrading to VoIP or moving to a fully hosted PBX system. 

The UK VoIP market is fragmented and is shared among 25 VoIP providers. If you’ve decided to shift to the latest technologies, you have two options: VoIP and cloud PBX. you will have to analyze your business requirements, required additional features and functionalities before you decide which option to go for.

Switching from ISDN to VoIP is easy as suppliers usually handle most of the groundwork for upgradation of phone systems.  In addition to choosing the right service provider, you will have to ensure that you have a reliable and fast internet connection to ensure quality services.

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