The Great British ISDN Switch Off – What does it mean for your business?

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End of ISDN road sign crossing out ISDN

In 2015, BT announced that they will be switching off the PSTN and ISDN in 2025, marking the biggest change in the telecoms industry for over 30 years, but what does the end of PSTN and ISDN mean for you?  We answer all your questions below:

What is the PSTN and ISDN Switch Off?

BT released a statement in 2015 that it would stop taking new ISDN orders in 2020, with a view to switching-off and deactivating its ISDN network completely at the end of December 2025. They will be transferring their networks from analogue and digital to an IP network.

Why is BT Openreach withdrawing the PSTN and ISDN network in December 2025?

In short, ISDN and PSTN are being replaced because they are now outdated systems that take too much time and too much money to keep running. In these highly technological times, it really makes no sense to keep running with such outdated systems when we have cutting edge technology at our fingertips.

By converging all services – voice, data, video, and even broadcasting to the IP protocol, BT also then only has to maintain one network, not several.

What other lines and calls services are impacted by the 2025 closure?

The PSTN supports a number of Openreach products: In technical acronyms these are known as WLR3 analogue, ISDN2, ISDN30, LLU SMPF, SLU SMPF, Narrowband Line Share and Classic products. These products are generically referred to, as WLR (Wholesale Line Rental) products. When the analogue network closes in 2025 these products will no longer be available.

Will BT Openreach provide the PSTN replacement products and services?

There are several BT Openreach alternative access products to underpin PSTN migration.  These include:

  • Single Order Transitional Access Product (SOTAP)
  • Single Order Generic Ethernet Access (SOGEA)
  • Single Order Gfast (SOGfast)
  • Fibre to the Cabinet (GEA-FTTC)
  • Fibre to the Premises (GEA-FTTP)
  • Ethernet
  • Metallic Path Facility (MPF)

These may require a ‘number porting activity’ where number retention is required when migrating away from the WLR product. This means if you have your fax or telephone using the phone line which you use for your broadband connection, that you will be able to port out your published number to another IP based service as opposed to losing this in 2025 which is good news.

Can you explain what these alternative copper and fibre services are and what they do?

Single Order Transitional Access Product (SOTAP) is a new product that will deliver a copper path between the end customer’s premises and the local telecom exchange infrastructure, over which broadband and IP voice services can be supported. This is different from MPF because it facilitates the use of existing exchange infrastructure which currently supports existing services. This therefore provides a better experience for end customers migrating away from WLR products.

Single Order GEA (SOGEA) will offer similar connectivity to GEA-FTTC (also known to us all as std fibre broadband) without the need for an underlying voice access product, offering speeds up to 80Mbps.

Single Order Gfast (SOGfast) is a cutting-edge new technology that allows us to deliver ultrafast Internet connection speeds over existing copper lines of up to 330Mbps.

Fibre to the Cabinet (FTTC) is a form of fibre optic communication delivery. The Optical fibre runs all the way from the exchange to the street cabinet. This then uses the existing copper network to reach the home or office. This tends to only be available to new developments where the connection to the telecoms network for the building has only recently been installed and BT Openreach have used fibre as opposed to copper.

Fibre to the Premises (GEA-FTTP) already enables ultrafast broadband speeds of up to 1Gbps download and 220Mbps upload and can be purchased on its own.

Ethernet which is also a fibre to the premise’s product offers a wide choice of high bandwidth, permanently connected, point-to-point services. The Ethernet fibre network that underpins this connectivity also known as leased line offers unrivalled geographic coverage of the UK, this tends to be the main product of choice for organisations who need something more secure and faster than broadband services available to their location.

What’s the alternative for end customers in areas with no fibre availability?

There are several options, including utilising the new Single Order Transitional Access Product (SOTAP) which uses broadband rather than voice as the primary service, as well as mobile and Ethernet services. Most organisations will simply convert their existing broadband phone line and broadband service to just a broadband service using the same pair of wires back to the exchange and losing the facility for phone and fax etc. on the underlying copper pair.

How and when will Openreach start withdrawing service?

The process of upgrading to IP voice services will be gradual but customers are encouraged to proactively contact your providers now, to discuss migration planning.

The traditional analogue phone network (the PSTN) is being retired in 2025. Openreach will stop selling WLR products that are reliant on the PSTN from September 2023. They will then completely close the WLR platform December 2025. After this date WLR products will longer be available.

Will new fibre products be more expensive than WLR?

This is a concern many providers have raised. Consumers can purchase a line for making and receiving calls for as little as £10 to £15. Whereas a full Fibre to the Premise (FTTP) service can begin at £50 per month. Arguably, this is a significant increase for those just wanting voice on their lines. For customers who do just want voice on their lines and have no requirement for broadband then a low bandwidth variant is expected but there is little information that has been published about this to date.

End of ISDN – Key dates:

November 2017 BT announced its intention to close the PSTN in 2025

May 2018  Openreach consultation on WLR withdrawal launched

July 2018  Openreach consultation closed

December 2018 Formal notification to stop selling products to be withdrawn (Gen073/18)

May 2019: SOGEA/SOGfast planned Early Market Deployment Launch

March 2020: Target date for SOTAP to commence trials

December 2020: Five-year reminder that WLR is being withdrawn

September 2023: Stop selling new supply of WLR PSTN, ISDN2 and ISDN30

April 2025: Orphaned assets phase

December 2025: WLR withdrawn

With the end of PSTN and ISDN services quickly approaching, why not call us to discuss your future options. Simply send us a copy of your current telephone bill to help us understand your current services. We can then provide a recommendation on when you should be planning to make the move towards VoIP services. Why not get in touch today on 0345 389 2310 to discuss your options. Alternatively, you can visit our Office VoIP Phone Systems page to find out how this great technology could improve your business.



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