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Published date: February 2017



For small to medium sized business looking to upgrade or replace their telephone system, the amount of choice can be quite overwhelming.
With businesses being driven by cost reduction, customer service and ever mobile workforces, the advancements in technology and the internet have undoubtedly expanded and the improved the choices that are now open to them.

Before companies would have queued to buy new and expensive telephone systems with ISDN lines; these days they’re looking for simpler and more cost-effective solutions.

While ISDN (digital transmission over copper lines) was the norm, it now lookslike an increasingly restrictive and expensive solution for organisations yet to deploy alternatives; especially now with more economic alternatives such as SIP in their sights. There is also a pending retirement of wholesale ISDN service by Openreach; scheduled for 2025 driving the ever increasing demand for VoIP (Voice over IP) services.

Companies often fail to rationalise their ISDN services when they are no longer required, resulting in unwantedline rental charges. ISDN is facing tough competition from easy -to-use IP services such as SIP that give the organisation fast and cost effective scalability.

For any organisation; flexibility is key! They may need to be able to scale their services up and down to account for seasonal fluctuations and peak demand. With ISDN, flexibility isn’t easy and you have to pay extra for increased lines, which can take weeks to install which would then be left unused during low season.

Against ISDN, the benefits of SIP Trunking are easy to grasp and visible for all to see. ISDN is an ageing technology and businesses that fail to replace it will soon become increasingly disadvantaged in terms of service quality, business agility and profitability.

Advantages of SIP Trunks

  • Converged voice and data network

The voice signal can use an existing internet connection therefore the management and control of a single network reduces complexity and overhead.

  • Easy and effective disaster recovery planning

SIP trunks provide far higher redundancy. In the event of failure at the customer site or the provider, the traffic can be instantly routed to a different location such as automated voicemail, or an external answering service. This can be incredibly useful for disaster recovery plans.

  • Consolidation and Flexibility

SIP isn’t geographically dependent so you can bring London numbers to Glasgow and Blackpool numbers to Bournemouth, thereby greatly reducing the requirements at each site and allowing a larger national presence to be deployed.

  • Quicker to deploy and scalable

SIP gets installed quicker (Typically within 48 hours vs. up to six weeks for an ISDN line) and can be scaled up and down on demand in the same timeframe.

Barriers to using SIP

“Our PBX doesn’t support SIP” – Most telephone systems are built with IP capability but some older, legacy systems that don’t can be converted with a low cost IP gateway platform.

Perhaps you’re in a contract already?

Depending on the length of this commitment this needn’t deter you. Call charges from SIP Trunk providers are often significantly lower than those charged by incumbent legacy service providers. This advantage may well outweigh any early termination fees. Also the reduction in your line rental costs can be very significant when moving to a SIP service.

“We don’t have the data line to support SIP” - If you have an existing connection to the internet; there are the capabilities to get you up and running quickly with technology to provide guaranteed quality of service.

If you have any further questions get in touch with our team. Let us help you get the most out of your telephone system, visit our Business Cloud Communications page.


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