SIP trunks are not just the latest buzzword. In the world of business telecommunications, it can sometimes seem like things are a little overcomplicated.


With so many acronyms, abbreviations and short-hand terms out there, it can sometimes seem a little overwhelming to choose the right system for a business. The term ‘SIP trunks’ is one such term that can be confusing at best. However, with so many benefits associated with this system, it’s definitely sensible to find out more about it and how it can help.


direct case study graphics-03The History of ISDN


When mass telecommunications systems first became popular, telephones often relied on the Public Switched Telephone Network (or PSTN). This was an age of simple communication, in some ways: a user could pick up their own phone, dial a number (either directly or via an exchange), and trigger a ring at the other end. The dominant system that eventually grew out of this mode of telecommunications was known as ISDN or, Integrated Services Digital Networks.


However, while ISDN may have been simple in theory, it was also risky. Renting a line over ISDN has become increasingly expensive over the years, especially as other technologies have surged forward in popularity. This has left businesses struggling to find an alternative, especially if they are concerned about potentially losing business if they take their phone system down altogether – but, conversely, failing to gain business if they don’t have an appropriate telephone contact system. The lack of scalability and flexibility with ISDNs can be hugely problematic, particularly for businesses that experience seasonal peaks and troughs in call volume.


With the 2025 switch-off on the horizon, it's time to consider the options available to provide future-proof business communications and this is certainly something SIP trunking can help support.


direct case study graphics-09What are SIP trunks?


The crucial difference between a SIP trunk and an ISDN, then, is that the former connects via an IP connection – or, in simple terms, the internet.

As with lots of internet-based services, it provides both cost and time savings. While this does not mean that a SIP trunk will never malfunction, it does tend to mean that reliability is higher than traditional telephone lines. The more reliable the internet connection, the stronger the SIP trunk tends to be – so by investing in a good high-speed internet connection, it’s possible to achieve a knock-on effect for phone calls.


direct case study graphics-02The Evolution of SIP


SIP trunks and IP telephony once had a reputation for hosting calls that were low quality in nature and that were not quite as dependable as those placed over the traditional ISDN networks. This was, perhaps, to be expected during the early days of the internet, when voice over IP solutions were still scrambling to find the best technical solutions to the problem of managing such demand for transmission.


However, since then, a huge amount of investment has been poured into the voice over IP world – and it is now the case that companies are able to offer high-quality SIP trunk solutions.


There are plenty of technical benefits to SIP trunking. Broadband networks, for example, can be set up in such a way that the SIP trunk is prioritised – meaning that the quality of a voice call can be maintained at all times, even at the expense of bandwidth on other parts of the network this is particularly beneficial for businesses which rely on both in and outbound calls.


direct case study graphics-10A Host of Benefits


While call quality is, of course, a key consideration, there are a whole host of other benefits for a business to take into account.


For a cost-conscious business thinking carefully about its bottom line, the lower costs involved in switching to SIP trunks is a big appeal. According to some, there’s a possibility of saving up to half when using SIP trunks as compared to conventional ISDN services – so there’s a real opportunity to reduce costs and ensure that the most cost-effective telecommunications system possible is in place.


It’s worth remembering, also, that SIP trunks can be integrated into a firm’s telecoms approach rather than added on as a new, additional service. For many people, this is a primary benefit of the SIP trunking system: it removes the need to have lots of different networks, which can clash as often as they cooperate, meaning a more streamlined, ‘unified communications’ approach – and even the possibility of integrating the trunk with a cloud-based server.


The other main tranche of benefits lies in the flexibility of a SIP trunking system. Because a SIP system is internet-powered, for example, it entirely bypasses the geographical restraints that are often placed on phone systems. Area codes, for example, can be used across the country, even if the call is being placed outside of that geographical boundary.


In recent years, SIP trunks have become popular as alternatives to the old ISDN mode of structuring telecommunications networks. With ISDN now being phased out and several exchanges entering a stop-sell in June 2021, the need for change is urgent.


For firms looking to cut down on costs, it’s easy to see why SIP trunks are so popular – but the benefits go far beyond just that. This voice over IP mode also offers lots of flexibility to users and allows for everything from area code options to cheap call forwarding. With broadband connections now able to be customised to ensure that call quality doesn’t slip, broken calls are pretty much a thing of the past and the flexibility and scalability provided




Why Wavenet?


When optimum call capacity is needed, SIP Trunks are the solution.

A true ISDN replacement, SIP Trunking future-proofs communication allowing businesses to get the most from their technology.

Having a high call capacity of up to 100 calls per second means you can run efficiently and cost-effectively, enabling your business to be brilliant.

By looking at emerging tech, we secure internet connectivity for today and tomorrow. Businesses achieve more with innovative technology that’ll never let them down.



"Our mission is to be the most respected provider of data, voice and technology in the UK."

Our solutions have been evolved over the last two decades to allow us to innovate and provide our customers with the future-proof technology they need to stay ahead of their competition. Broken into four simple groups, our solutions cover all aspects of business communications and technology.
  • Unified Communications & Voice
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Wavenet is a respected, multi-award-winning provider of telecoms and technology solutions to thousands of businesses and enterprises across the UK.


We are passionate about being at the forefront of disruptive technology providing our customers with the innovation and infrastructure to truly outperform their competitors.


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