BSNL's homegrown 4G network carries 6 petabytes of data daily as India expands its indigenous telecom stack.

State-run Bharat Sanchar Nigam Limited (BSNL) has reached a major operational milestone with its homegrown fourth-generation (4G) mobile network, which is now handling an average of 6 petabytes (PB) of data traffic every day. Speaking on C-DoT’s 43rd foundation day, Rajkumar Upadhyay, Chief Executive Officer of the Centre for Development of Telematics (C-DoT), revealed that this traffic is powered by 1.75 lakh indigenously developed 4G base stations deployed across 100,000 sites nationwide. The network currently delivers services to more than 2.2 crore 4G subscribers out of BSNL’s total user base of roughly 9.3 crore, marking the first successful large-scale commercial run of an Indian-designed and manufactured telecom network.
The entire infrastructure was deployed by a domestic consortium led by Tata Consultancy Services (TCS), which paired radio access network (RAN) equipment from Tejas Networks with core network software engineered by C-DoT. Alongside high-speed data connectivity, C-DoT has rolled out an indigenous IP Multimedia Subsystem (IMS) that currently delivers high-definition (HD) voice calling in seven telecom circles, with plans to expand HD calling across the entire country over the coming months. This domestic architecture allows BSNL to significantly modernize its service quality and mount a viable challenge against private rivals like Reliance Jio, Bharti Airtel, and Vodafone Idea.
The network has also been built to ensure an easy and cost-effective upgrade path to 5G without requiring complete hardware overhauls. C-DoT has already deployed its 5G non-standalone (NSA) core across BSNL circles, while its standalone (SA) core is under active development. In parallel, an indigenous carrier-grade 5G radio system-developed alongside Indian startup WiSig and electronics manufacturer VVDN Technologies-is undergoing live field trials on BSNL’s 3.6 to 3.7 GHz spectrum in Ambala. To build a long-term supply chain and pursue global equipment exports, C-DoT has transferred its radio manufacturing technology to domestic public sector firms including ITI Limited, Bharat Electronics Limited (BEL), and ECIL.