Software Engineer | Cloud Native BNG Solution Testing, Scale & Performance, Python | 8-12 year

Overview

As a Software Engineer on the cnBNG Solution Testing team, you will own end-to-end solution, scale, performance, and resiliency validation of carrier-grade broadband deployments running on IOS-XR routing platforms. You will design service-provider network topologies, automate subscriber and traffic scenarios, analyze system and forwarding performance, debug solution-level issues, and provide release-readiness recommendations.

What you'll do

• Design and implement end-to-end cnBNG solution testing across Control Plane, User Plane, subscriber management, forwarding, platform infrastructure, and external network elements.
• Own scale and performance qualification covering subscriber scale, session setup and teardown rates, throughput, latency, packet loss, convergence, CPU and memory utilization, and sustained-load behavior.
• Develop service-provider test topologies covering PPPoE, IPoE, DHCPv4/v6, PPP, RADIUS/CoA, L2TP, subscriber policies, accounting, QoS, and subscriber lifecycle scenarios.
• Build and validate large-scale cnBNG deployments with multiple Control Plane and User Plane nodes.
• Use Keysight IXIA and Spirent for subscriber emulation, protocol emulation, traffic generation, traffic analysis, performance benchmarking, and large-scale test execution.
• Create traffic profiles covering mixed IPv4/IPv6 traffic, multiple packet sizes, bidirectional traffic, QoS classes, and subscriber service profiles.
• Validate CUPS / CP-UP separation, including session programming, state synchronization, state replay, reconciliation, failures, and recovery scenarios.
• Perform high-availability and resiliency testing, including SRG geo/warm standby, process restart, node and link failures, ISSU, NSR/NSF, control-plane failures, and subscriber session continuity.
• Validate IOS-XR forwarding functionality including L2/L3 forwarding, FIB/adjacency, MPLS/L3VPN, H-QoS/policing, ACLs, mirroring, OAM/BFD, slowpath, and NPU forwarding behavior.
• Develop and maintain scalable Python-based test automation using pyATS/Genie or equivalent frameworks, integrating tests into CI/CD pipelines and regression suites.
• Build reusable automation libraries for topology setup, subscriber provisioning, traffic generation, fault injection, statistics collection, verification, and automated result analysis.
• Analyze performance trends and identify bottlenecks across software, forwarding hardware, NPU resources, CPU, memory, and control-plane interactions.
• Perform soak, longevity, stress, negative, boundary, and capacity testing.
• Validate subscriber QoS, accounting, lawful intercept, policy enforcement, CLI, YANG models, model-driven telemetry, gRPC/NETCONF/gNMI, and operational data.
• Debug solution-level issues using IOS-XR logs, traces, telemetry, packet captures, core dumps, IXIA/Spirent statistics, and platform/NPU diagnostics.
• Isolate root causes across the Control Plane, User Plane, forwarding infrastructure, Silicon One NPU, automation environment, traffic generator, and external network components.
• Partner with development, platform, system architecture, and customer-facing engineering teams to reproduce defects and drive them to closure.
• Define measurable test exit criteria and provide data-driven release-quality and readiness recommendations.
• Use Git and modern software-development practices for automation code, test reviews, defect management, and CI/CD integration.
• Use approved AI coding assistants and engineering agents for automation development, test generation, log analysis, failure clustering, defect analysis, and troubleshooting while validating AI-generated output.
• Mentor junior engineers and improve solution-testing methodology, automation architecture, scale infrastructure, and engineering quality.

What you'll need

• Bachelor's or master's degree in Computer Science, Electrical/Computer Engineering, Telecommunications, or a related field.
• Strong experience in system, solution, scale, performance, and resiliency testing of networking products or carrier-grade networking solutions.
• Strong understanding of functional, integration, system, regression, scale, performance, stress, longevity, failover, and high-availability testing methodologies.
• Hands-on expertise with Keysight IXIA and/or Spirent traffic-generation platforms, including protocol emulation, subscriber emulation, traffic generation, scale testing, and performance analysis.
• Strong Python programming and experience developing scalable test automation using pyATS/Genie or equivalent frameworks.
• Experience integrating automated test suites into CI/CD and continuous regression pipelines.
• Strong IP networking fundamentals, including L2/L3 forwarding, IPv4/IPv6, routing, MPLS/L3VPN, and QoS.
• Knowledge of broadband/subscriber technologies and protocols including PPPoE, IPoE, DHCPv4/v6, PPP, RADIUS/CoA, and L2TP.
• Experience configuring, validating, and solving IOS-XR or another carrier-grade network operating system.
• Ability to design and implement large-scale network topologies and characterize capacity, throughput, latency, convergence, resource utilization, and failure recovery.
• Strong understanding of high availability, duplication, subscriber-state management, and fault-recovery mechanisms.
• Strong Linux skills and experience with Git, debugging tools, packet collections, logs, telemetry, and defect-management systems.
• Strong solving and analytical skills with the ability to isolate sophisticated issues across traffic generators, network protocols, software, hardware, and forwarding layers.
• AI-assisted engineering is a must, including use of AI coding assistants such as GitHub Copilot and a working understanding of generative AI, AI agents, MCP (Model Context Protocol), reusable AI skills, prompt/context management, responsible validation of AI-generated output, and AI-assisted log and defect analysis.

Nice to have

• Experience validating cnBNG, BNG, or broadband subscriber solutions.
• Experience with CUPS / Control Plane–User Plane separation and large-scale distributed User Plane deployments.
• Sophisticated experience with IXIA BreakingPoint/IxNetwork and/or Spirent Test Center, including automation APIs and large-scale subscriber/traffic emulation.
• Experience with Cisco 8000, ASR 9000, NCS 5500/5700, Silicon One, or comparable carrier-grade routing platforms and NPUs.
• Experience validating subscriber scale, session churn, traffic performance, convergence, and long-duration stability.
• Experience with SRG geo/warm excess, ISSU, NSR/NSF, and service continuity testing.
• Knowledge of SRv6/Segment Routing, MPLS, EVPN/VPLS, TE/GRE tunnels, BFD, BGP Flowspec, and ACLs.
• Experience with YANG, gRPC, NETCONF, gNMI, OpenConfig, and telemetry.
• Experience building automated performance dashboards, test-result analytics, failure classification, and regression trend analysis.
• Familiarity with Aha/Jira APIs engineering and defect-management integrations.

Details

• Location: Bangalore, India.