C++ Firewall & Network Security

About the Role:

You will play a key role in designing and developing high-performance firewall components, including packet filtering, deep packet inspection (DPI), policy enforcement, and network traffic analysis. The ideal candidate shall have a deep understanding of network protocols, C++ systems programming, and multithreading for real-time packet processing.

Responsibilities:

• Design and implement next-generation firewall modules using C++17/20, focusing on network-layer filtering, connection tracking, and application-level control.
• Build and optimize network packet processing pipelines using raw sockets or libraries like libpcap.
• Develop Deep Packet Inspection (DPI) and application detection engines, leveraging libraries like nDPI or custom solutions.
• Work with core network protocols, including TCP, UDP, ICMP, HTTP/S, DNS, FTP, and TLS.
• Integrate and utilize OpenSSL for TLS inspection and to secure control channels, such as HTTPS APIs.
• Develop or interface with rule engines for access control, rate limiting, and traffic shaping.
• Contribute to the development of alerting systems, log collectors, and network health monitoring tools.
• Optimize code for latency and throughput using concurrency control, SIMD, and lock-free techniques.
• Work with multi-interface systems and manage network configurations on Linux/Windows stacks, including handling updates to routing and firewall tables (iptables, pf, iproute2).
• Collaborate with GUI teams to expose REST or gRPC APIs for management interfaces.

Requirements:

• 2+ years of professional experience in modern C++ (C++11/14/17/20), with a strong foundation in OOP and the Standard Template Library (STL).
• In-depth knowledge of the OSI model and networking protocols from Layer 2 to Layer 7.
• Hands-on experience with TCP/IP socket programming, packet parsing, and flow/session tracking.
• Strong understanding of TLS/SSL, encryption techniques (RSA, AES), and OpenSSL APIs.
• Demonstrated experience with multithreading, concurrency primitives, and performance optimization.
• Familiarity with network protocol analysis tools such as Wireshark and tcpdump.
• Proficiency in Linux/Unix internals, network configuration, and system diagnostics.

Preferred Qualifications:

• Experience with firewalls, NGFW, intrusion detection, or network sniffers.
• Knowledge of specific networking frameworks and tools like libpcap, nDPI, Netfilter/iptables, pfctl, or eBPF.
• Familiarity with high availability (HA) concepts, VRRP/CARP, or clustered deployments.
• Experience with Protobuf, gRPC, REST APIs, and secure service design.
• Background in security appliances, VPNs, or Windows Credential Providers.
• Familiarity with log management and integration with SIEM systems.

Experience: 2–7 years
Department: Network Security & Systems Engineering
CTC: up to 18 LPA(Depending on experience)