Software Engineer | C or C++, Packet/Slow Path , L2& L3 Protocols | Bangalore | 7 + to 10 years

123 Cisco Systems (India) Private Limited; Bengaluru; On-site; INR 4,500,000 - 7,000,000; Full time

Job summary

123 Cisco Systems (India) Private Limited is seeking an experienced Software Engineer to design, implement, and optimize forwarding software for Layer 2 and Layer 3 features on high‑performance NPUs within the IOS-XR platform.

You will work on QOS, Mirroring, OAM, EVPN/VPLS, SRv6, MPLS, and related technologies, using C/C++ and Python, and apply AI‑driven methods to speed up development and debugging.

Qualifications

• 7+ years of embedded software development experience in networking products.
• Strong programming skills in C/C++ and Python scripting.
• Solid knowledge of carrier-grade networking OS and forwarding architectures.

Responsibilities

• Hands-on design, coding, and optimization of forwarding software for L2/L3 features.
• Deliver production-grade code for QOS, Mirroring, OAM, EVPN/VPLS, SRv6, MPLS on NPUs.
• Debug complex defects using logs, core dumps, and packet traces.
• Profile and optimize for latency and throughput to meet performance metrics.
• Leverage AI/LLM-based tools for code generation, tests, and analysis.

Skills

C/C++

Python

Embedded systems

Networking OS

GDB

Tools

Clearcase

Valgrind

DDTS

GDB

Job description

Who we are

You will join the MIG Platform Forwarding team, the engine room behind the world’s most robust service provider networks. We build the high-performance data plane software that powers IOS-XR platforms, leveraging cutting-edge Silicon One (SiOne) Network Processing Units (NPUs). Our team operates at the intersection of hardware and software, defining how packets traverse the internet's backbone. We are transitioning into a new era of embedded development, utilizing modern AI-assisted methodologies to deliver features faster and with higher quality.

Your Impact

As a Software Engineer, you will focus on the hands‑on design, coding, and optimization of our forwarding software. You will be responsible for delivering high‑quality code for complex Layer 2 and Layer 3 forwarding features , , ensuring they extract maximum performance from our NPUs. You will act as a key technical contributor, utilizing modern software practices and AI‑driven workflows to streamline development and debugging.

Feature Design & Implementation

Own the design and development of specific forwarding features within the IOS-XR platform. Write high-performance, production-grade code for QOS, Mirroring , Slowpath , OAM, Layer 2 (EVPN, VPLS) and Layer 3 (SRv6, Segment Routing, MPLS) technologies.

NPU Data Plane Programming

Implement data plane logic to optimize packet processing. Translate network protocol requirements into efficient NPU microcode and SDK interactions.

Debugging & Root Cause Analysis

Investigate and resolve complex software defects found during internal testing or customer deployments. Analyze logs, core dumps, and packet traces to distinguish between NPU behavior and software logic issues.

Performance Optimization

Profile and tune code to minimize latency and maximize throughput, ensuring the software meets strict service provider performance metrics.

Modern Development Practices

Actively utilize AI/LLM-based tools for code generation, unit test creation, and static analysis to improve individual productivity and code quality.

Minimum Qualifications

• 7+ -10 years of experience in embedded software development for networking products. Strong programming skills in C/C++ and scripting in Python Solid knowledge of carrier-grade networking OS and forwarding architectures. Experience debugging complex embedded software issues. Experience working on tools such as Clearcase, Valgrind, DDTS, GDB, etc. Embedded Development: Strong proficiency in **C/C++** for high-performance embedded systems. Proficiency in Python for scripting and test automation. NPU Familiarity: Working knowledge of NPU-based data plane architectures (e.g., Broadcom DNX, Silicon One, or ezChip). Understanding of pipelining, table management, and packet processing flows. Forwarding Protocols (L2/L3): Strong understanding and implementation experience in Qos, Mirroring, OAM , Layer 2 (EVPN, VPLS) or Layer 3 routing (SRv6, Segment Routing, MPLS, IPv4/v6). Implementation experience with TE-Tunnels, GRE tunnels, BFD, BGP Flowspec, ACLs, or Slowpath forwarding mechanisms. Network Knowledge & Debugging: Service Provider Context: Understanding of router deployments in Service Provider networks (Core, Peering). Technical Troubleshooting: Ability to debug issues at the component level, including hardware/software interactions and memory management.

Preferred Qualifications

• Experience with **IOS-XR** or similar carrier-grade network operating systems Knowledge of Internet Protocols (TCP/UDP, IPv4/IPv6). Exposure to Networking Protocols (L2/L3, QoS, ACLs,). Experience with BCM , Sione,, Ezchip NPU programming Familiarity with AI/ML tools for software engineering (e.g., Copilot for code, AI for log analysis).

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.