Senior Software Engineer - IPv6 Networking exp is a must**

About the role

For more than 30 years, SonicWall has delivered a partner-first unified cybersecurity portfolio that helps SMBs, MSPs, and IT teams consolidate network security, endpoint security, security service edge (SSE), and threat response across hybrid environments. By bringing connected technology, real-time threat intelligence, automation, and expert services together, SonicWall helps organizations simplify security operations, achieve better security outcomes, and lower total cost of ownership. Backed by a global ecosystem of more than 17,000 partners, SonicWall delivers enterprise-grade protection built for SMB and mid-market realities.

For more information, visit www.sonicwall.com or follow us on X, LinkedIn, Facebook, and Instagram.

SonicWall is seeking a Senior Software Engineer with deep IPv6 expertise to lead the design, implementation, and hardening of IPv6 capabilities across the Sonicwall firewall firmware stack. As a Principal Engineer, you will be the technical authority for IPv6 feature parity, protocol correctness, and interoperability across SonicWall Next-Generation Firewall (NGFW) platforms. This role is ideal for engineers with hands-on experience delivering IPv6 in high-performance router, switch, or carrier-grade networking products who are looking to apply that expertise in the embedded network security domain.

Responsibilities

• Lead IPv6 Architecture & Feature Delivery — Own end-to-end design and implementation of IPv6 features across the Sonicwall frewall networking stack, including IPv6 routing, interface addressing, DHCPv6, NDP, MLDv2, and IPv6 Policy-Based Routing (PBR).

• Drive IPv6 Feature Parity — Identify and close gaps between IPv4 and IPv6 feature sets across subsystems — including VPN Tunnel Interfaces, IPsec/IKEv2, SSL-VPN, Syslog, SNMP, and NAT64 — ensuring consistent dual-stack and IPv6-only operation.

• Design High-Performance IPv6 Packet Processing Paths — Architect and optimize the IPv6 dataplane for packet forwarding, classification, ACL matching, and session lookup within the sonicwall high-performance packet-processing pipeline.

• Resolve Complex IPv6 Protocol Issues — Diagnose and resolve deep-rooted interoperability, conformance, and performance issues involving IPv6 neighbor discovery, prefix delegation, ICMPv6 error handling, and fragmentation edge cases.

• Establish IPv6 Protocol Conformance Standards — Define and drive compliance with IETF IPv6 RFCs (RFC 2460, RFC 4291, RFC 4861, RFC 4862, RFC 6724, RFC 8200, and related extensions) within the Sonicwall frewall codebase.

• Cross-Functional Collaboration — Work closely with Platform, Security, Data Platform, and QA teams to integrate IPv6 changes safely across subsystems and validate correctness at scale.

• Prototype and Evaluate IPv6 Technologies — Evaluate emerging IPv6 transition mechanisms (464XLAT, MAP-T, CLAT, SRv6) and contribute to next-generation NGFW networking capabilities.

• Influence Technical Direction — Drive architectural decisions, IPv6 scalability strategies, and long-term technical roadmap for protocol parity and government/federal compliance (USGv6, IPv6-ready certification, DoD IPv6 mandates).

• Mentorship & Technical Leadership — Serve as the IPv6 subject-matter expert (SME) for the Sonicwall frewall engineering org; mentor senior and mid-level engineers and lead cross-team IPv6 technical design reviews.

Requirements

• 7- 9+ years of hands-on C/C++ systems-level development for networking platforms — with a strong emphasis on routers, Layer-3 switches, carrier-grade NAT (CGNAT) devices, or network security appliances.

• Deep IPv6 Protocol Expertise — Proven, production-level implementation experience with:

• IPv6 addressing, subnetting, and prefix delegation (DHCPv6-PD)

• Neighbor Discovery Protocol (NDP), Router Advertisements (RA), and MLDv2

• IPv6 routing protocols (OSPFv3, BGP with IPv6 AFI/SAFI, RIPng)

• IPsec/IKEv2 over IPv6 transport

• IPv6 ACLs, PBR, and traffic classification at line rate

• IPv6 transition and coexistence mechanisms (Dual-Stack, 6in4, 6rd, NAT64/DNS64, 464XLAT)

• L2/L3/L4 Networking Depth — Solid understanding of Ethernet, VLANs, 802.1Q, bridging, routing (static and dynamic), NAT, firewall state tables, and VPN tunneling in the context of both IPv4 and IPv6.

• High-Performance Packet Processing — Experience with DPDK, ODP, OFP, XDP/eBPF, or comparable frameworks for low-latency, high-throughput packet forwarding is a strong advantage.

• Protocol Conformance & Testing — Experience validating IPv6 implementations against IETF RFC requirements and government IPv6-ready test suites (USGv6, IPv6-Ready Logo Phase-2) is highly desirable.

• Strong Debugging & Diagnostic Skills — Proficient with tcpdump, Wireshark (IPv6 dissectors), GDB, kernel trace tools, and network emulation environments (GNS3, EVE-NG, or equivalent) for root-cause analysis of IPv6 issues.

• Communication & Leadership — Excellent written and verbal communication skills with the proven ability to lead cross-functional IPv6 design discussions, write technical specifications, and represent engineering in product and architecture reviews.

Nice to Have

• Experience with government / federal IPv6 compliance requirements (DoD IPv6 mandate, NIST SP 500-267, USGv6 Profile).

• Exposure to SRv6 (Segment Routing over IPv6) or MPLS over IPv6 architectures.

• Familiarity with Sonicwall frewall, SonicWall NGFWs, or similar embedded network security firmware.

• Working knowledge of WireGuard over IPv6 transport.

• Experience with automated IPv6 test frameworks (RFC 2544, IXIA, Spirent, or similar).

#LI-DS9

#LI-Pune

#LI-Hybrid

#LI-IPv6

At SonicWall, we pride ourselves on recruiting a diverse mix of talented people and providing active security solutions in 100+ countries.