David Hammond Email & Phone Number

Enfield, England, United Kingdom

Technical lead for the Azure Edge Networking Fabric team, responsible for delivering WiFi/5G convergence and security features in a scalable Kubernetes-based microservice architecture at the Azure cloud edge.Features were written in Rust, and my day-to-day work required liaising with architecture, PM, DevOps, other feature teams, and external technology partners, as well as technical direction and feature development.In this role I have:- Ran technical interviews and made hiring recommendations to grow our team from 4 to 10 personnel.- Architected, designed and implemented the function for WiFi integration and convergence.- Architected, designed and implemented security features including microsegmentation and ACLs.- Performed initial prototyping of In-Service Software Upgrade (ISSU) and developed tools for visualizing and debugging the process.

Enfield, England, United Kingdom

Technical lead within the Network Protocols Division - responsible for delivering SONiC Open Networking integration and migrating our division's codebase post-acquisition to Microsoft's systems.My features were developed in C/C++, and centered around MPLS and IP forwarding/routing technologies. My day-to-day work was split between feature development, architectural input, task-managing a contractor team, and assisting the wider team with education and tooling.My technical features included:- Prototyping and productizing a SONiC compliant Linux-based software dataplane, able to forward IP and MPLS and apply access-control. This enabled partner teams within Microsoft to accelerate their testing and time-to-market.- Augmenting the division's diagnostics systems. This unlocked new data for our customer support teams and immediately improved their time-to-fix for customer-critical issues.- Successfully trailblazing the first CI migration from gitlab to Azure DevOps for acquired Metaswitch codebases.I was responsible for task-managing and providing technical leadership to a 6-8 person contractor team located in Romania - this involved:- Defining work and acting as PO in their scrums.- Providing technical education and help, including travelling to Bucharest to host a week-long seminar and workshop session.- Assessing each contractor's performance and productivity and providing regular reports to management.- Ensuring the quality of their output through technical review.

Enfield, England, United Kingdom

Technical lead within the Network Protocols Division - responsible for delivering Segment Routing features and task-managing a contractor team.My features were developed in C/C++ and tested in Python; they covered interactions with IP routing, MPLS, LDP, LFA, TI-LFA, OSPF and traffic-engineering.My technical features included:- Architecting, developing and testing a Segment Routing solution, which attracted customers to the greater ease of use and performance SR provides over pre-existing technologies.- Augmenting our DevOps systems to be able to accurately isolate bugs found from long-running test suites.- Creating an innovative new testing framework, which allowed the division to catch semantic interface mismatch issues much earlier in the development cycle.I was responsible for task-managing and providing technical leadership to a 6-8 person contractor team located in Romania - this involved:- Defining work and acting as PO in their scrums.- Providing technical education and help.- Assessing each contractor's performance and productivity and providing regular reports to management.- Ensuring the quality of their output through technical review.

Enfield, England, United Kingdom

Developer on the Session Border Controller team - responsible for a wide variety of VoIP features and Linux kernel development on a high-performance, high-reliability product.I performed architecture, design, code, testing and support roles, and worked on a huge variety of features spanning multiple disciplines. The 'Perimeta' SBC was a carrier-grade VoIP security/interoperability system, relied on by tier-1 telcos to facilitate and protect networks serving millions of subscribers. All features had to ensure 5 9s+ reliability, accommodate 4M subscribers and 10k+ active calls.Highlights:- Architected, prototyped and productized a high-performance dataplane within a Linux kernel module. This formed the foundation of our commodity hardware offering, worth $10M+.- Inventor for multiple patents, relating to cross-system media optimization and high-performance anti-Denial-of-Service algorithms.- Developed a semantic fuzzer tool which found and reproduced over 300 unique bugs in field-hardened code within a week of deployment. Then augmented it with genetic algorithm heuristics to find 90 more.Projects:- Signaling: Several SIP features. Push notifications (APNS). WebRTC integration.- Media: Dataplane API and implementation (control- and data-side). High-performance media packet forwarding. Fax support and interworking. DTMF detection, suppression and injection. Support for multiple fixed- and variable-bitrate codecs. Jitter buffering. Instant messaging (MSRP).- Security: Authentication, header filtering, topology-hiding, IPsec, ACLs, dynamic firewalling and defence against denial of service, anti-spoofing measures (STIR/SHAKEN), Lawful Intercept, Secure RTP.- Interoperability: Dynamic message editing, SIP/H.323 interworking, media transcoding and transrating.- Network architecture: IMS integration, VoLTE integration, NAT traversal (STUN), e911 compliance.- System architecture: In-Service Software Upgrade, High Availability.

Enfield, England, United Kingdom

Developer within the Network Protocols Division - responsible for implementing protocol features to be sold as source-code to customers using multiple OSs (including embedded).I performed design, code and testing for my features, all written in C.Projects:- Session Initiation Protocol: Adding protocol features, implementing OpenSSL integration, and developing proxy function.- Protocol Independent Multicast: Parsing and forwarding functionality, performance optimization.