Senior Embedded Networking Engineer

About the role

We build and extend firmware for managed industrial Ethernet switches used in factories, utilities, transportation and other environments where the network cannot go down. You will work on the protocol stack at the heart of these switches: how frames are bridged, how loops are prevented, how a ring recovers within milliseconds when a link fails, and how traffic is routed between networks.

The role suits a hands-on engineer who has shipped Layer 2 and Layer 3 features on real switch hardware, knows the standards well enough, and can trace a convergence problem from a packet capture down to the switch ASIC. Redundancy work, including Distributed RSTP (DRSTP) and recovery-time optimization, is a core part of the current work.

Key responsibilities

• Design, implement and maintain Layer 2 features on embedded switch platforms: VLANs, MAC learning and ageing, link aggregation (LACP), LLDP, IGMP/MLD snooping, port security and QoS.
• Own spanning-tree and redundancy features: STP, RSTP and MSTP, Distributed RSTP (DRSTP) and ring coupling, including analyzing and optimizing failover and recovery times.
• Design, implement and maintain Layer 3 features: static and dynamic routing (OSPF, RIP), ARP and neighbor discovery, VRRP, DHCP relay, IPv4 and IPv6 forwarding, and VRF where the platform supports it.
• Work across the control plane and data plane: integrate protocol software with the switch silicon through the vendor SDK (Broadcom, Marvell or similar), covering table programming, port and trunk configuration, CPU packet path, hardware events and link-state handling.
• Debug complex field and lab issues across the stack using packet captures, traffic generators, SDK diagnostics and kernel or system logs; drive root-cause analysis to closure.
• Write design documents and test plans; review code and designs from other engineers.
• Work with test teams on protocol conformance, interoperability and performance testing, including convergence-time measurement.
• Interact directly with customers on technical requirements, feasibility studies and issue resolution.
• Mentor junior engineers on networking concepts and embedded development practices.

Required experience and skills

Experience

• 8 to 10 years of software development on Layer 2 and Layer 3 networking products, with at least 5 years on embedded switch or router platforms.
• A track record of shipping protocol features into production, not only maintaining them.

Layer 2

• Strong working knowledge of IEEE 802.1D, 802.1w (RSTP), 802.1s (MSTP), 802.1Q and 802.1AX (LACP), including state machines, timers and edge cases.
• Hands-on experience with Distributed RSTP (DRSTP) or comparable redundancy schemes (for example multi-chassis link aggregation, IEEE 802.1AX DRNI, MRP/IEC 62439-2 or ERPS/G.8032), including tuning for fast recovery.
• Experience with LLDP, IGMP/MLD snooping, MAC table management and Layer 2 QoS.

Layer 3

• Solid knowledge of IPv4 and IPv6 forwarding, ARP and neighbor discovery, static routing and at least one dynamic routing protocol (OSPF preferred).
• Experience with VRRP and DHCP relay.

Control plane and data plane

• Clear understanding of control plane, data plane and management plane separation on switches and routers, and how protocol state is programmed into hardware forwarding tables.
• Experience on the control plane: protocol state machines, the CPU packet path (trapping, punting and injecting control frames such as BPDUs, LACPDUs and routing packets), and control-plane policing.
• Experience on the data plane: programming MAC, VLAN, L3 host and route tables, ACLs and QoS in the ASIC, and handling hardware events such as link changes, table-full and learning events.
• Ability to debug mismatches between software state and hardware state, and to optimize the path from a control-plane decision to the data plane, which is critical for fast convergence.

Embedded and platform

• Expert C programming in a multi-threaded embedded environment; working knowledge of C++ and scripting (Python or shell).
• Embedded Linux: cross-compilation, build systems, kernel/user-space interaction, IPC and debugging with gdb and tracing tools.
• Experience with a switch ASIC SDK (Broadcom, Marvell or similar).
• Fluent with Wireshark, traffic generators (Ixia, Spirent or similar) and lab test setups.

Good to have

• Experience with industrial Ethernet switch platforms, for example Hirschmann HiOS, Moxa, Siemens SCALANCE or Cisco Industrial Ethernet.
• Familiarity with industrial redundancy and timing standards: IEC 62439 (MRP, HSR/PRP), IEEE 1588 PTP.
• Exposure to secure development practices, ideally IEC 62443-4-1/4-2.
• Management-plane work: CLI, SNMP/MIB design, web management, NETCONF/YANG.
• Experience connecting devices to cloud management platforms (TLS, MQTT, NATS or WebSockets).
• Prior customer-facing role in feasibility studies or effort estimation.

Interested? Apply here or drop your resume at apin.lal@gadgeon.com