Colt says goodbye to legacy TDM networks in Europe

Published by Colt Technology Services on October 16, 2023

We have successfully concluded our transition away from TDM (Time Division Multiplexing) networks in Europe, marking a significant turning point in Colt’s history. This is an important milestone for us on our journey towards network modernisation and enhanced sustainability.

After powering down the final 32 switches, we are now free of TDM networks in Europe after migrating profitable voice customers to alternate platforms. This is a legacy that has ruled the telecommunications industry for five decades and a transformation project that has taken four years of hard work to accomplish.

Our efforts have led to a substantial annual reduction in energy consumption, where we anticipate saving an impressive 13.2GWh. We’ve successfully removed 130,000 legacy circuits from our network. The replaced services now offer customers seamless access to cutting-edge digital infrastructure, ensuring a superior and more reliable experience. Over 6,500 devices, representing over 15 network platforms across 2,000 sites in Europe, have been successfully decommissioned.

More than 2,800 of our valued customers can now experience a wider range of digital capabilities such as On Demand, VoIP and IP Telephony digital services which will help them grow, stay competitive and thrive in today’s business landscape.

Colt’s Lyon office marks the end of an era – just one example of the positive impact of the TDM removal

It was just recently that our Colt Lyon office in France switched off its Nortel DMS telephony system after 24 years of service. The DMS, which provided TDM voice services to customers, has been slowly transitioned to Voice over IP and IP Telephony. The new system requires significantly less energy and space to function.

DMS was used by Colt in most European countries and dozens of cabinets have been replaced by simple pairs of routers which drastically reduce power consumption and help with cooling.

Vincent Peigné, Director Sales Engineers at Colt, commented on this particular transition:

“We are all sad to say goodbye to our dear DMS system. It’s been in use for so many years that it’s become quite nostalgic. Many other large devices have also been shut down on our data-network side, allowing us to adopt new solutions that require less energy.”

Greener tech at Colt

Greener technology is big part of Colt’s strategy (ESG By Design) and ongoing commitment to sustainability. It is our aim to create lean, green and modular digital infrastructure where network optimisation is instilled as a continuous discipline.

Technology plays a major role in facilitating the transition to a lower carbon future and we are enabling customers in this transformation through sustainable products, services, and equipment design and by promoting digital inclusion.

Many of the recent actions we have taken to ensure our business model continues to fundamentally support sustainable development are showcased in our recent Sustainability report. To list a few examples:

  • In addition to phasing out the TDM voice services, we are also reducing energy with our SDH end-of-life programme which aims to remove all the infrastructure connected to SDH transport technology
  • 14,739 pieces of second hand equipment were purchased in 2021 and 2022, and 75,452 pieces of equipment were re-used. We have also expanded our Investment Recovery (IR) programme where we redeploy, resell or recycle redundant equipment and onboarded more IR partners.

If you want to learn more about Colt’s sustainability initiatives, download our latest Sustainability report or head to our ESG page where you can also hear from our CEO, Keri Gilder, on this topic.

Colt’s Vice President of Network Engineering, Vivek Gaur

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