Cultural shift powers C-DOT’s push in India’s telecom innovation

In an era defined by digital sovereignty and secure networks, C-DOT has emerged as India’s strategic telecom R&D force and the Voice&Data Pathbreaker of the Year for 2024. Under the leadership of its CEO, Dr Rajkumar Upadhyay, the institution has evolved from a legacy body into a national innovation engine. From 4G core and IMS deployments to quantum communication and cyber intelligence platforms, C-DOT is developing solutions that address both technological and strategic imperatives. In this wide-ranging conversation, he shares insights into C-DOT’s transformation, its collaborative model, and the core technologies it is working on. Excerpts:

Voice&Data Award celebrates both individual leadership and institutional transformation. How do you view this recognition in the context of C-DOT’s evolving role in India’s digital communications landscape?

I consider this recognition an honour not just for myself, but for the C-DOT team. It validates our long-standing commitment to building indigenous technology solutions that serve India’s larger strategic needs. It is a tribute to C-DOT’s mission and our contribution to nation-building.

Back in the 1990s, we revolutionised rural telecom, and the same spirit is now driving us once again. Our focus is aligned with the Prime Minister’s vision of Atmanirbhar Bharat. We see ourselves as active contributors to this larger national mission, and I must emphasise that none of this would have been possible without the phenomenal support from the government.

This award energises our engineers and reinforces our belief that we are on the right path. It is not the end, but the beginning of a renewed push to build cutting-edge telecom innovations for India.

C-DOT’s revival is truly inspiring—from being a legacy institution to driving cutting-edge technology. What strategic shifts enabled this remarkable transformation?

Several factors contribute to this transformation, but I would attribute it primarily to the government’s clear and consistent support. The push towards developing indigenous technologies has been a big motivator, and the clarity from the government made a significant difference.

It started with three fundamental pivots. First, we focused on our people. We addressed their concerns, provided them with the tools and freedom to innovate, and fostered a culture of trust. My leadership style is facilitative—I enable my leaders, rather than micromanaging them.

The second key shift was strategic focus. We had too many projects running in parallel, and that was stretching us thin. So, we decided to focus on areas where we could create a national impact. We asked ourselves: where can C-DOT make a real difference? No more routine work—only challenges that others were not solving.

The third, and equally important, shift was our approach to collaboration. We realised we cannot—and should not—do everything alone. We now work closely with startups, academia, and industry. This cultural shift has been central to our revival.

You mentioned collaboration as a key pillar. How significant was the joint effort with Tejas and TCS in building and deploying the indigenous 4G stack?

This was a defining moment. When I joined C-DOT in 2020, the idea of developing a full 4G stack indigenously was still in its infancy. That is when C-DOT, Tejas, and TCS came together to explore what could be done. Honestly, neither C-DOT nor Tejas was fully prepared for such an endeavour. However, the partnership with TCS gave us the confidence that this was possible.

Frankly, very few believed we could do it. Such systems had only been built in Finland, Sweden, China, and to some extent, Korea. Neither Japan, nor Russia, nor the US had developed a full stack on its own. Naturally, there was scepticism. However, the political leadership was clear and fully committed to this mission. Their backing reaffirmed what the Prime Minister often says: we have the talent—why can we not do it? In fact, we did not hire new talent; the existing C-DOT team delivered this.

C-DOT’s 4G core, IMS, and 5G NSA deployments are now live in BSNL’s network, serving over 15 million users and radiating across 1.4 lakh BTS sites.

We signed the formal agreement with TCS and Tejas in January 2021. By mid-2022, we had the stack ready. Today, over 1.4 lakh BTS sites are operational, with 15 million users connected to the network, and we deliver 3.5 petabytes of data daily. Even components like IMS, which were initially not assigned to us, were later entrusted to C-DOT. We have deployed these in states like Haryana and Rajasthan, replacing legacy foreign systems. Gradually, we will roll out our IMS nationwide. This is a strong proof point of India’s capability.

BSNL deserves appreciation too. They provided the opportunity to test the technology in a live environment. Their engineers, who had extensive experience working with foreign technologies, provided valuable feedback.

What about 5G? Where does C-DOT currently stand?

We have already deployed our 5G NSA (Non-Standalone) core in BSNL’s network. The government also made a conscious decision to develop 5G radios indigenously. Had BSNL opted to import radios, it could have launched 5G much earlier. But building the ecosystem was the priority.

Accordingly, C-DOT funded two consortia under a collaborative model—one comprising VVDN and WiSig, and the other with Lekha Wireless, Signaltron Systems, Sooktha Consulting, and Resonous Technologies. These groups, together with C-DOT, are developing indigenous 5G radios. These are undergoing field trials in Ambala and will soon be deployed nationwide once stability tests are complete. The 5G SA (Standalone) core is also under development and being tested in academic institutions.

While applications such as URLLC and mMTC are still evolving, their adoption will necessitate a full-fledged SA core. We are deploying the SA core in universities as part of our skills development initiative. Since 6G is already on the horizon, it is vital to ensure hands-on 5G exposure for academia. Our university programme provides cost-effective test labs, enabling students and researchers to gain experience with 5G. This will also help India be better prepared for 6G.

How mature is this portfolio, and do you see commercial traction, particularly in sectors such as defence, railways, and enterprise networks?

We first developed 4G radios to gain that capability. Today, I am pleased to share that we have developed 4G radios across all required frequency bands—Band 1, 3, 5, 8, 28, and 40. Our first field trial of 4G radios was conducted successfully with Indian Railways over a 25-kilometre stretch in Secunderabad. We are now conducting a 500-kilometre trial with the railways and additional trials with defence establishments. The radios developed with VVDN and WiSig under a collaborative framework are undergoing rigorous testing in Ambala.

Efforts to jointly develop 5G radios with startups like VVDN and WiSig mark India’s bold step towards full-stack, indigenous telecom solutions.

Our 5G radios are undergoing stringent Detailed Technical Requirements (DTR) testing with BSNL. It is a tough process, but it ensures high product maturity. The same collaborative approach that worked for 4G—C-DOT, Tejas, and TCS—is now expanding to include more startups for 5G. Thanks to the foundation built with 4G, we are not far behind in 5G. The base is ready, and the ecosystem is gaining maturity.

Talking about BSNL’s stringent testing process, was it easier or more difficult for C-DOT—as a public sector company—to supply technology to another PSU?

It was both. Initially, no one thought we could meet the DTR specifications. It was extremely exhaustive—perhaps drawn from the best global players. Initially, we found the testing process overwhelming. Additionally, there were supplementary tests beyond the DTR. But eventually, we realised it helped our product become more robust and mature.

BSNL is like a museum of telecom technologies—they have equipment deployed from Siemens, Motorola, Nortel, Alcatel, and more, many of which have now shut down. Our system had to interwork with all of these legacy platforms. That was a huge challenge. But we succeeded, and that gives us confidence that our systems can now operate in any global network.

C-DOT is also building India’s cybersecurity muscle. How do you foresee the challenge, and how are you addressing it?

As networks shift to IP-based architectures—5G being fully IP-based, and even 4G to a large extent—the attack surface expands significantly. The emergence of IoT, M2M communications, and AI-powered networks has only added to this complexity. However, one significant advantage is that when the code is under your control, you can manage at least half of the security challenges internally. You know what your code is, and you can immediately patch any vulnerability. This is important when it comes to network security.

We entered this space only a couple of years ago, but have made significant progress. We now have systems that can detect and mitigate threats across sectors and the national digital infrastructure. For example, our Trinetra platform not only helps identify threats in real time but also enables stakeholders to neutralise them.

Cybersecurity is fast becoming one of the most critical areas of concern. In times of emergency or conflict, adversaries can bring down critical networks. During Operation Sindoor, we saw millions of attack attempts in just 30 minutes. That is the scale we are dealing with. Critical infrastructure, such as power, telecom, and banking, is all under threat. Our platform provides real-time alerts and tools to counteract these threats. Telecom, being foundational, is our top priority.

You have also developed several AI-driven tools. How are these shaping India’s digital trust framework?

Our AI platforms are central to this mission. Sanchar Saathi has helped disconnect over 35 million fraudulent connections. This platform uses AI to detect fraudulent telecom connections. We have also developed ASTR, a solution that uses AI and facial recognition to identify fraudulent SIM registrations. This tool helps detect not only fake identities but also the point-of-sale agents involved in enabling these frauds.

Another major innovation is the Centralised International Out Roamer (CIOR), designed to detect spoofed calls made using falsified Indian numbers. It identifies and blocks these calls during the call setup stage itself, significantly reducing the risk of social engineering attacks and other security threats.

AI-driven platforms such as Sanchar Saathi, CEIR, and CIOR are helping build India’s digital trust framework by tackling fraud, spoofing, and network security.

As networks become more connected, we are also focusing on securing the Internet of Things. The National Trust Centre (NTC) is being developed to ensure that only trusted IoT devices are onboarded. Rogue IoT elements pose a serious threat and can compromise entire networks if not managed securely.

We have also developed a Central Equipment Identity Register (CEIR), which detects fraudulent IMEIs in the network. These not only pose commercial risks but are also serious security threats. CEIR helps to block such devices and prevent misuse. In addition, we have launched the Digital Intelligence Platform (DIP). This is a backend engine that integrates with citizen-facing services and generates actionable intelligence for various stakeholders, including law enforcement agencies, telecom operators, banks, and others. Our AI stack supports lawful interception, threat detection, and fraud analytics—all in real time. That is how we are building digital trust.

C-DOT is also working in high-tech quantum space. What is the roadmap there?

The encryption algorithms we use today are robust to the extent that classical computers cannot break them. The computational power required is simply beyond the capabilities of conventional systems. However, quantum computing changes the game.

While quantum computers will bring immense benefits across sectors, they also pose a significant threat. They will eventually break the encryption standards we currently rely on for banking transactions, digital communication, and secure networks. That is the fundamental challenge we need to address.

This is where quantum-safe communication comes in. It involves building cryptographic systems, and at C-DOT, we are working on two such technologies: Quantum Key Distribution (QKD), based on the principles of physics, and Post-Quantum Cryptography (PQC), based on advanced mathematical algorithms. Both of these are designed to be resistant to quantum-level attacks.

Importantly, these are not just lab prototypes. We have production-grade systems. Our QKD solution has been operational for over two and a half years between Sanchar Bhavan and NIC. We have also deployed it at AIIMS and IIT Madras, and shared the technology with several universities for further research. We are also part of the National Quantum Mission, co-leading the quantum communication vertical with IIT Madras. Quantum is a greenfield area—no country has a big lead yet. That gives India a level playing field. We aim to lead, not follow.

What is your long-term vision for C-DOT?

C-DOT has seen significant growth over the past few years. From Rs 80 crore in revenue when I joined, to over Rs 1,000 crore expected this year. Our team size remains lean—approximately 1,500—but we achieve more with less. As our revenue increases, we will be able to expand our workforce and accelerate development, improving our speed to market.

C-DOT’s role will be crucial in building technologies that are important not just from an economic perspective but also from a national security standpoint. It will be central to building India’s strategic tech infrastructure. Buying technology may be cheaper at times, but indigenisation is vital for national security.

We also aim to be a global hub for R&D. We have already transferred our 4G and IMS technologies to TCS for implementation globally. Our mission is to address high-impact problems, collaborate with industry and academia, and position India as a global leader in telecom technology.