For millions of users, the internet is the backbone of daily life. Whether it’s enabling global businesses to operate seamlessly, supporting life-critical systems like healthcare and aviation, or providing reliable communication during emergencies, uninterrupted connectivity has become a non-negotiable expectation. Behind this reliability lies an intricate web of technologies managed by service providers, who face mounting challenges to ensure networks remain secure, efficient, and always online.
One of the most critical components in this ecosystem is the Broadband Network Gateway (BNG), a device that controls the flow of data between users and the wider internet. BNGs are the unsung heroes of modern connectivity, quietly managing the flow of internet traffic between millions of users and the global web. Acting as a control center, they prioritize data, enforce security, and ensure quality of service for everything from streaming platforms to enterprise applications. With the rise of cloud computing, 5G networks, and the Internet of Things (IoT), the demands placed on BNGs have grown exponentially.
Today’s networks are no longer static systems—they are dynamic ecosystems that must support billions of devices, adapt to rapid changes, and maintain peak performance around the clock. As service providers strive to meet this demand, the ability to update and improve their infrastructure without disruptions has become a linchpin of success. Enter the In-Service Software Upgrade (ISSU)—a transformative innovation that has redefined how service providers approach network upgrades. At the forefront of this advancement is Seshagirirao Lekkala, whose pioneering work on ISSU for Ericsson’s BNG routers has set a new standard for reliability and efficiency in the telecommunications industry.
The Challenge: Keeping Networks Online During Upgrades
The role of a BNG in modern networks cannot be overstated. Acting as the gateway between a subscriber’s home and the wider internet, these routers manage traffic, prioritize data to ensure quality of service, and enforce security measures. Any disruption to their operation can lead to widespread outages, particularly affecting industries that rely on constant connectivity, such as the aviation sector, financial institutions, and public safety organizations.
Yet, upgrading the software of these routers has historically been fraught with challenges. The upgrades often required taking the router offline, which not only disrupted services but also necessitated complex workarounds, such as rerouting traffic or deploying additional hardware. These methods added operational costs and increased the network’s carbon footprint.
“For service providers, even a few minutes of downtime can have cascading effects on their operations,” explains Seshagirirao Lekkala. “Delaying upgrades to avoid downtime is not a sustainable solution because it leaves networks vulnerable to security threats and inefficiencies.”
The inability to upgrade seamlessly also became a bottleneck in deploying new technologies, particularly for enabling 5G networks, where uninterrupted service is critical to maintaining the high-speed, low-latency promise of the technology.
The Innovation: In-Service Software Upgrades (ISSU)
- Recognizing these challenges, Lekkala took the lead in developing a solution that would enable service providers to upgrade their BNG routers without any downtime. The ISSU process achieves this by maintaining continuous synchronization between the router’s active and standby processors. During the upgrade, the active processor continues operations while replicating real-time state information to the standby processor. The standby is upgraded and takes over as the active processor through a switchover. The former active processor is then upgraded, ensuring minimal downtime and continuous service.
This innovation required designing a meticulous state machine to manage the states, transitions, and actions involved in the upgrade process. Lekkala also implemented the protocol to establish a secure, reliable communication channel for data synchronization between the active and standby processors.. This ensured that all critical state information and configurations were replicated in real time, allowing the standby processor to take over seamlessly during the upgrade.
“The real challenge was ensuring that no packet was lost, even during the transition between processors,” Lekkala explains. “It required a precise coordination of processes and robust communication between the nodes to make the upgrade completely invisible to the end user.”
Transforming the Industry
The implementation of ISSU had a profound impact on Ericsson’s BNG routers and the broader industry. By eliminating downtime during upgrades, service providers could maintain uninterrupted service, significantly reducing downtime associated with failovers.
Additionally, the ISSU process streamlined the 5G enablement process for Ericsson’s customers, reinforcing the company’s leadership in the telecommunications space. The ability to roll out 5G networks without interruptions allowed providers to meet the high reliability standards demanded by industries like autonomous vehicles, remote healthcare, and real-time financial trading.
The environmental impact of the innovation was equally significant. By eliminating the need for additional hardware to manage upgrades, ISSU reduced the carbon footprint of network operations, aligning with the industry’s sustainability goals.
“Our work on ISSU not only made networks more robust but also helped service providers reduce their environmental impact,” says Lekkala. “This is a step toward building more sustainable and efficient digital infrastructure.”
The Broader Context: Challenges in Network Reliability
The need for innovations like ISSU underscores the growing complexity of modern networks. As businesses and consumers increasingly depend on internet connectivity for their daily operations, the tolerance for downtime is shrinking. The global cost of internet outages is estimated to be over $300,000 per hour for businesses, according to ITIC (ITICReport).
In addition, the rapid adoption of technologies like 5G/6G and IoT has placed unprecedented demands on network infrastructure. With billions of devices expected to be connected by 2030, service providers are under pressure to ensure that their networks are not only reliable but also scalable and secure.
Leadership in Action
Seshagirirao Lekkala’s leadership in developing ISSU highlights the critical role of engineers in solving some of the most pressing challenges in network management. His ability to anticipate the needs of service providers and design a solution that balances technical complexity with practical impact has set a new benchmark in the industry.
“Innovation is not just about solving the problem in front of you—it’s about thinking ahead to what the industry will need five or ten years from now,” Lekkala reflects. “ISSU was about enabling service providers to future-proof their networks and stay ahead in a rapidly changing landscape.”
Conclusion
The development of In-Service Software Upgrades for BNG routers represents a significant step forward in ensuring uninterrupted internet connectivity. By eliminating downtime, reducing operational costs, and paving the way for 5G/6G and other next-generation technologies, this innovation has transformed how networks are managed.
For industries and consumers alike, the impact of seamless upgrades is felt every day—in uninterrupted video calls, reliable financial transactions, and the seamless operation of critical systems. Behind it all are visionaries like Seshagirirao Lekkala, whose work continues to shape the future of our connected world.
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