05 December 2023

Bharti Airtel, which offers mobile, wireless, fixed line and high-speed broadband to consumers and businesses throughout India, has one of the world’s largest voice over LTE (VoLTE) services in the world.

Dedicated to providing a world-class experience, Bharti Airtel turned to Nokia to help ensure a seamless and uninterrupted service experience for its customers.

A unique solution

Nokia Core Networks Global Services was able to implement the largest VoLTE geo-redundancy disaster recovery solution rapidly and cost-efficiently for the 155 million subscribers of Bharti Airtel in India.

When deployed as a cloud solution, VoLTE uses the data capacity of the 4G/LTE network and a cloud-based IMS (internet multimedia services) server that is located in the core network to provide a full range of voice and, potentially, video communications. The quality of voice calls is much higher than traditional circuit-switched voice services and, as a result of Nokia’s implementation, is now supported by all of today’s generation of Android and Apple smartphones.

VoLTE voice services are also capable of delivering highly flexible services to enterprise customers that integrate with enterprise unified communications systems. They can support field agents with the ability to combine data and video exchanges seamlessly into the call.

Moreover, services such as the Bharti Airtel Emergency Alerts Service, which allows subscribers to alert up to 10 loved ones with one call, also rely on the availability of the system during disaster situations. It is critical, therefore, that these business- and mission-critical applications are highly reliable and secure, even in the case of disaster.

Creating redundancy

“Nokia and Airtel together designed and deployed a unique disaster recovery (DR) solution specific to Airtel, which uses N+1 mode with a single DR hub able to support multiple active hubs,” said Rashim Kapoor, senior vice president – core networks, Bharti Airtel.

The Nokia solution was designed to create N+1 redundancy. This means that for all 12 hubs, there would always be one additional core available to replace the failure of a single regional hub.

This 12+1 DR core, which provides the disaster recovery backup, includes all Nokia core network functions, including the IMS functions needed for VoLTE. In the case that one of the Bharti regional hubs fails, there is an automatic cutover to the redundant DR hub without service interruption.

“The best part is that the switchover from active hub to DR hub in case of any failure, happens automatically without any service impact,” said Kapoor. “This has resulted in a highly available and resilient network with much better customer experience as the services remain available even in case of any partial or complete failure of any of the hubs. As a result, Airtel is confidently moving faster to convert the entire circuit-switched voice network to Nokia’s VoLTE IMS solution, thus improving VoLTE uptake in the Indian market.”

As a result of the collaboration, Bharti Airtel’s 155 million subscribers across the continent now have access to more high quality, resilient communications via voice than ever before.