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SIP Trunks


Session Initiation Protocol (SIP) lines send voice and data over one single internet connection. This can either work alongside your existing phone lines or replace them altogether.

Calls are routed through the web across the Public Switch Telephone Network (PTSN) using Voice over Internet Protocol (VoIP). Because you’re not using a traditional phone line, calls between your offices can be made without any cost at all, significantly reducing your monthly call costs and line rental charges.

SIP also allows you, should you wish, to set up a geographical number that’s separate from the actual location of your office.

ISDN (Integrated Services Digital Network) is due to be discontinued by 2025 and is being replaced by SIP trunking- a public IP based telephony system that runs on Session Initiation Protocol (SIP) lines. The new technology offers a cost effective, modern way to communicate and delivers a range of benefits.

Benefits include:

  • A reduction of up to 50% in line rental (sometimes even more!)
  • Full future proofing
  • Built in disaster recovery and continuity
  • No need to change your number when you transfer over to SIP- your existing number can be easily ported across using next generation voice switches
  • Automated switching to secondary calling routes
  • Calls directed to any number you want
  • No tie in to telephone exchanges
  • Crystal clear calls with HD audio

Why move to SIP trunking from ISDN?

ISDN will be obsolete by 2025, so you’ll have to move over sooner or later and it makes sense to start taking advantage of the many advantages of SIP now. You’ll be able to start saving money because SIP trunks are delivered over data lines that you’re likely already using for your internet connection. Fewer lines are required with SIP trunking too, which also means fewer charges. SIP trunks also include built in disaster recovery.

If you’re unavailable to take a call the system will automatically switch to an alternative calling route- this can be anything from a mobile phone to an office in a totally different country. Great news for avoiding unanswered calls and unhappy customers. It’s a flexible and highly scalable business solution too, allowing you to adapt your phone lines and change the amount of channels you have available as you grow. All your numbers will be hosted in one central database, eliminating the need for call forwarding.

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To find out more about SIP trunks and how they can help your business, call LMS on 0330 088 2565

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Service Delivery KPIs June 2019

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