Software Engineer (C and Python, Linux OS, networking domain, L2/L3 forwarding protocols| 4-9 Years)

123 Cisco Systems (India) Private Limited; Bengaluru; On-site; INR 1,400,000 - 2,100,000; Full time

Job summary

123 Cisco Systems (India) Private Limited in Bengaluru is seeking a Software Engineer for the BNG User Plane. You will design, code, optimize, and validate the subscriber forwarding path on Silicon One UPFs, delivering high-performance L2/L3 features.

You will own unit, integration, and system testing, drive automation, and mentor junior engineers while leveraging AI-powered development practices in a carrier-grade environment.

Qualifications

• 4-9 Years of Experience along with Bachelor’s degree in CS/EE/EC or technical equivalent.
• Strong programming in C/C++ for high-performance embedded systems; Python for test automation and scripting.
• Proven understanding of GenAI capabilities and AI-powered software development.
• Sound knowledge of operating system concepts, computer networking, multithreaded programming and system programming on UNIX based systems.

Responsibilities

• Design, code, optimize, and validate the subscriber forwarding path on Silicon One UPFs.
• Deliver high-performance L2/L3 and subscriber features with unit/integration/system testing.
• Automate testing and development workflows, mentor junior engineers.

Skills

C/C++ programming

Python

GenAI awareness

UNIX OS concepts

Networking fundamentals

Education

Bachelor’s degree in CS/EE/EC or equivalent

Job description

Meet the Team

The Cisco BNG User Plane team builds the carrier-grade subscriber data path on IOS-XR routing platforms (Cisco 8000, ASR 9000) powered by Cisco Silicon One (SiOne) NPUs. We deliver the cnBNG User Plane Functions (UPFs) and integrated BNG forwarding — the high-performance packet path that terminates and forwards millions of broadband subscriber sessions at line rate in the CP-UP separated (CUPS) architecture. We operate at the intersection of hardware and software, value automation-first engineering and continuous learning, and responsibly embrace AI-assisted development practices.

Your Impact

As a Software Engineer on the BNG User Plane, you will design, code, optimize, and validate the subscriber forwarding path on Silicon One UPFs and its interworking with the cnBNG Control Plane. You will deliver high-performance L2/L3 and subscriber features, own their unit/integration/system/scale testing and automation, and drive quality from design through FCS. You will mentor junior engineers and use modern AI-driven workflows to streamline development, testing, and debugging.

Minimum Qualifications

4-9 Years of Experience along with Bachelor’s degree in CS/EE/EC or technical equivalent. Strong programming in C/C++ for high-performance embedded systems; Python for test automation and scripting. Proven understanding of GenAI capabilities and AI-powered software development Sound knowledge of operating system concepts, computer networking, multithreaded programming and system programming on UNIX based systems.

Preferred Qualifications

Broadband/subscriber protocols: PPPoE, IPoE, DHCPv4/v6, PPP, RADIUS/CoA, L2TP. Experience configuring and troubleshooting IOS-XR or another carrier-grade network OS. Exposure to L2/L3 protocols plus.

Why Cisco?

At Cisco, we’re revolutionizing how data and infrastructure connect and protect organizations in the AI era – and beyond. We’ve been innovating fearlessly for 40 years to create solutions that power how humans and technology work together across the physical and digital worlds. These solutions provide customers with unparalleled security, visibility, and insights across the entire digital footprint. Fueled by the depth and breadth of our technology, we experiment and create meaningful solutions. Add to that our worldwide network of doers and experts, and you’ll see that the opportunities to grow and build are limitless. We work as a team, collaborating with empathy to make really big things happen on a global scale. Because our solutions are everywhere, our impact is everywhere. We are Cisco, and our power starts with you.

Cisconians power the future. We make impact as a team, innovating fast and fearlessly to create meaningful solutions on a large scale. The depth and breadth of our technology doesn't just benefit our customers – it also means limitless opportunities for us to experiment and learn. We understand the power each of our unique backgrounds bring when we work together. Because of that, we have a global network of thinkers, doers, experts, and curious creators who help one another do their life’s best work.