What is VoIP?

VoIP allows you to make voice calls and voice services using your broadband internet connection.

VoIP replaces your PSTN/ISDN analogue phone systems.

Using VoIP services provides an opportunity to improve your communication and collaboration services, realise financial efficiencies and simplify operations.

How to move to VoIP

Moving to VoIP now will not only modernise your communications network but will future proof you against the upcoming UK wide switch off of PSTN and ISDN lines. Moving to VoIP gives you the benefits of a modern telephony infrastructure, such as:

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Cost control and predictability

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Business continuity

Operational efficiency

Your move to VoIP can follow one or more technology paths

We can help you to develop and implement your VoIP services, including:

Why make the move to VoIP calling now?

In 2025 BT Openreach will switch off the PSTN and ISDN networks.

PSTN and ISDN lines provide the voice calls connectivity for legacy telephone systems. They connect your PBX or switchboard to the wider public telephone network.

Put simply, the PSTN is the telecommunications platform that has been in use for the last century that has carried nearly all UK phone calls. Integrated services digital network (IDSN) uses traditional copper PSTN telephone lines and splits them into multiple digital channels.

Neither ISDN and PSTN can meet the needs of today’s demand for faster and larger data connections.

It’s not just your phone services you need to think about. It’s everything else that currently uses the phone network, this might include but not be limited to:

  • ISDN20 and ISDN30
  • Alarm lines
  • CCTV
  • Door entry systems
  • Electronic point of sale and card machines
  • Remote telemetry systems
  • Fax machines
  • Lift alarms
VoIP calling
VoIP calling

Our VoIP services

Your transition to VoIP

To ensure a smooth transition to VoIP and you get the most from your investments, we have designed services to help. Dependant on how your organisation operates you may use more than one service.

Large organisations with a high number of users and complex phone system requirements can use our VoIP services when considering migrating to:

We will also support your essential services, such as alarm and payment systems, by providing continuity internet connection through Single order Generic Ethernet Access (SoGEA) or Fibre to the Premise (FTTP) broadband.

If your organisation has minimal phone numbers and handsets, you can use our Phoneline+ service to keep your phones and numbers working. Your voice calls will be delivered over a data connection using VoIP technology.

To make sure you have a smooth transition to VoIP, we can manage your PSTN and ISDN services for you which will reduce your costs and resources.

Why Trustmarque for VoIP services?

Our voice network services team has over 20 years of experience in delivering voice solutions to large and small organisations.

Taking a customer-centric approach to solution design, our consultants work with you to understand your business and technical priorities. Then design solutions to meet them, drawing on a range of solution options to achieve your desired outcome. We work closely with a range of partners including Gamma, Colt, BT Openreach, TalkTalk Business, Cisco and Microsoft.

We were awarded the Gamma Telecom Direct Routing Partner of the Year Award in 2021 and 2022

Cisco Gold Partner
Microsoft Gold Partner
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