Bring your comms together with
One Voice SIP

Save money by putting your calls in the cloud.

Bring your comms together with
One Voice SIP

Save money by putting your calls in the cloud.
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Existing customers0800 085 595709:00 - 18:00 | Monday to Friday

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Lay the foundations for cloud transformation

Lay the foundations for cloud transformation

The cloud is calling. One voice SIP offers an IP alternative to traditional voice services. It helps you take control of your costs, while keeping up with growing business demands and embracing new collaboration tools.

  • Reduce costs

    Eliminate expensive interfaces and reduce the number of channels you need to handle your traffic.
  • Freedom and flexibility

    Give your people the freedom and flexibility to work efficiently throughout the UK.
  • 24/7 support

    You can contact our dedicated UK-based helpdesk for support whenever you need us.
  • Reduce costs

    Eliminate expensive interfaces and reduce the number of channels you need to handle your traffic.
  • Freedom and flexibility

    Give your people the freedom and flexibility to work efficiently throughout the UK.
  • 24/7 support

    You can contact our dedicated UK-based helpdesk for support whenever you need us.

Link your systems

Hybrid working has made it difficult for some corporate firms to communicate and collaborate effectively, affecting efficiency and the cost of connectivity. One Voice SIP provides connectivity from a SIP enabled PBX to the PSTN, helping consolidate IT and communications infrastructure, streamlining your costs and simplifying some of the associated management processes. This allows you to keep your existing hardware, unlike with many hosted solutions.

Helping Kingston’s drive for students

During busy recruitment drives, outdated technology couldn’t cope with the marked increase in calls coming through to Kingston University. This was losing them potential students, but our IP solution transformed how people work at the university.

Why BT

We combine deep expertise with extensive capabilities in cloud, networking, security and creating unified communication solutions. We’ll help you define your strategy and provide end-to-end management to simplify your operations.

We’re people obsessed

We put your people at the core of all solutions so they get a more enjoyable digital, physical and secure experience, which means they can work more efficiently and generate more value for you.

You can rely on our network

Our network is trusted by thousands of organisations to keep them safe. And our experts can work with multiple technologies and legacy systems to create a single, secure network for your business, too.

We’re security specialists

We protect governments, critical national infrastructure and global corporations from more than 6,500 daily cyber-attacks. This gives us an overview of the complex security threat landscape, so our 3,000 security experts can help better protect your organisation.

We’re investing in your future

We’ve invested £2.5 billion in research and development over the last five years. And we’ve filed more than 10,000 patents since 1990, so we’re always pushing the boundaries of how we can help you achieve your goals.

We’re people obsessed

We put your people at the core of all solutions so they get a more enjoyable digital, physical and secure experience, which means they can work more efficiently and generate more value for you.

You can rely on our network

Our network is trusted by thousands of organisations to keep them safe. And our experts can work with multiple technologies and legacy systems to create a single, secure network for your business, too.

We’re security specialists

We protect governments, critical national infrastructure and global corporations from more than 6,500 daily cyber-attacks. This gives us an overview of the complex security threat landscape, so our 3,000 security experts can help better protect your organisation.

We’re investing in your future

We’ve invested £2.5 billion in research and development over the last five years. And we’ve filed more than 10,000 patents since 1990, so we’re always pushing the boundaries of how we can help you achieve your goals.

FAQs

What is SIP?

Session Initiation Protocol (SIP) is used to provision voice over IP (VoIP) connectivity between a PBX and the PSTN. One Voice SIP is an alternative to ISDN30 that uses your data network to route your PSTN traffic. It can help improve organisational flexibility, offer additional resilience and operational efficiency whilst helping to reduce costs

What is the difference between a SIP channel, a SIP Trunk and a SIP Trunk Group?

A SIP Channel is the capacity needed to carry a single telephone call and is an attribute of both a Trunk and a Trunk Group. The number of channels determines how big a Trunk or Trunk Group is.

A SIP Trunk is the connection to a PBX has a designated number of Channels. This channel capacity is also referred to as the trunk’s Call Admission Control (CAC)

A SIP Trunk Group in turn also has a designated number of Channels and is a container for Trunks. So Trunks sit in Trunk Groups and multiple Trunks can sit in the same Trunk Group. This capability is useful if you want to separate a set number of channels for your business and likewise for your contact centre

How does One Voice SIP offer resilience between sites work and will it cost me more?

One Voice SIP offers in-built resilience at no extra cost, routing calls to an alternative (stand-by) site if your primary site becomes unavailable. Some providers will charge for ‘stand-by’ channels but BT only charges for channels in use at any time.