Are You Ready for the PSTN/ISDN 2025 Switch Off?

With the convergence of voice and data, BT Openreach announced in April 2017 that they will phase out their existing copper wire PSTN telephone network by 2025. Anyone currently using PSTN- or ISDN-based services will have to switch to another service before then.

Despite this deadline, a recent survey by National Business Communications revealed that 70% of UK businesses are still using landlines and an astonishing 24% are not even aware of BT Openreach’s plan to discontinue traditional copper wire telephone services.

Are you ready for the “Big Switch Off”? Let us do the work for you.

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What Is the Alternative?

Session Initiation Protocol (SIP) technology bridges the gap between traditional telephony and digital voice-over-IP (VoIP). SIP Trunking allows you to make and receive calls using the SIP protocol over an Internet connection (IP line). Because SIP Trunking utilizes existing telephone equipment/infrastructure, it is a reliable and flexible alternative for businesses looking to switch from ISDN (or PSTN) to VoIP. Although not every business has the same PBX, SIP Trunking offers a solution for every business thanks to its many possible configurations.

  • SIP Trunking in conjunction with an on-premises PBX: If a VoIP PBX is installed on site, a SIP trunk is required to connect to the outside world.
  • SIP Trunking in conjunction with an on-premises ISDN exchange: Connect the exchange directly via an ISDN-to-SIP gateway on a fixed-line network
  • SIP Trunking as a hybrid solution: installing a SIP trunk in combination with a Gateway on a legacy PBX. This allows all calls to be processed over the new IP lines.

Why You Should Consider SIP Trunking

Benefits of SIP Trunking

Don't let inflexible and costly inbound/outbound telephone services impact your business. Using SIP Trunks with your business telephone system gives you access to the features and benefits of VoIP technology, including:

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Lower Costs

Save up to 50% compared to traditional or legacy options, such as ISDN. Plus, you can reduce the maintenance costs of your PBX and benefit from free calls within the UK.

Flexibility & Scalability

SIP Trunking provides easier IT administration, desktop telephony, number flexibility, and much more. It is also instantly scalable, so you can add and remove trunks as required.

Service Continuity

Moving to VoIP is a seamless process that won't leave you without your business phone for days. Acting now, before there is a huge demand for these services, is advised to ensure a swift and easy deployment.

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Seamless Migration

SIP Trunks can be integrated with all IP PBX systems, giving you peace of mind that any transition is frictionless.

Black Box SIP Trunking Partners


Why Black Box

With more than four decades of experience implementing in-building IT and communications technologies around the world, local certified teams, and a proven track record of providing best-in-class consultancy, field, and support services, Black Box can help you transition to VoIP seamlessly and at your own pace.

By working with our experienced team, you can minimize any risk to continuity and reliability of your telephone services both during and after the migration. Our extensive field service engineering team can support you on-site or remote with any local installation requirements.

Avoid last-minute mass migrations to SIP!

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Work quickly to identify needs and outline a plan of action. Contact a Black Box expert today.