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Network Services and Infrastructure

Making a risk-free move from ISDN to SIP


Over the last few years there has been an ongoing debate about the rate of decline of ISDN lines in the UK – and their gradual replacement with SIP trunks.

frustrated man with head on desk and holding phone away from ear

While there is a decreasing number who still view SIP as just an emerging technology, the reality is that the market is transitioning across at an accelerated pace. Since 2008 around one million ISDN channels have ‘disappeared’, with SIP proving the major benefactor.

According to Illume Research*, research conducted during the last six months of 2013 found that almost 200,000 SIP trunks were added – taking UK SIP trunks past the one million trunk mark for the first time. By far the largest factor for organisations switching from ISDN to SIP is cost – a fact echoed by Sabio’s recent announcement that a growing number of its customers are now enjoying significant savings on SIP trunk channel costs compared to their previous fixed ISDN line expenditure.

In the enterprise space, independently-sourced research has shown that around 50% of IT and Telecoms Managers are now ready to deploy SIP trunking, with the question of confidence in call quality now effectively redundant as all the components needed to ensure a quality service are now in place. Perhaps this growing confidence stems from the fact that Voice Over IP using SIP and other protocols has been in play on the LAN/WAN side of the business for some significant time. So, for a growing number of enterprise technology managers, the replacement of ISDN with SIP is no longer a great leap of faith.

We’ve also seen the introduction of competitive access options such as FTTC Ethernet, EFM for the mid-market and the falling costs of Ethernet in the Enterprise space. These serve as additional SIP market drivers, as well as the broader imperative to converge an organisation’s voice and data requirements. Additional market considerations include operational management tasks such as flexing channels, new service deployments, and the addition of further Disaster Recovery (DR) capabilities.

With DR particularly, the concept of resilient designs is now considered as a ‘business as usual approach’ for SIP trunking. Taking advantage of the soft switch nature of SIP means that services can now be pre-provisioned to automatically failover and divert traffic instantly. This serves as a far more cost effective manner than traditional TDM services. Just compare ISDN’s service assurance options with those of a carrier grade SIP provider and the choice is compelling. With SIP it’s all about IP routing, and it doesn’t get more flexible than that.

Change is clearly afoot in the UK telecoms market. For the customer the only real question to consider is that of selecting the right partner to help them manage their shift to SIP. At Gamma, we can point to our continued growth, market share, experience, and skilled and dedicated channel partners such as Sabio as key reasons why organisations should now be thinking Gamma and Sabio when they commit to moving across to SIP.

To learn more about SIP and how Gamma supports Sabio Network Services in bringing you the best blend of service, technology, commercial flexibility and pricing, contact [email protected].

*Illume Research – UK IP/SIP Trunking Market Report & Forecast – January 2014-2018


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