Branimir Rajtar
Branimir Rajtar is the CTO and co-founder of 5×9 Networks, where he focuses on the design and development of software-based broadband networking platforms. He has worked on virtualized BNG solutions and network automation for more than a decade, with a particular interest in high-performance packet processing and scalable network architectures. Branimir is also active in the network operator community as the chair of NOG.HR, the Croatian Network Operator Group, helping organize technical events and knowledge sharing among network engineers.
Session
This presentation describes the journey of achieving more than 1 Tbps throughput on a single x86 server by evolving a virtualized Broadband Network Gateway (vBNG). It walks through practical lessons learned while scaling from early multi-VM designs to a high-performance, single virtual machine capable of high packet rates. The talk covers the role of SR-IOV and Intel DPDK, extensive hardware tuning, deep code-level optimizations, and major redesigns driven by CPU cache behavior and PCIe bottlenecks. Real-world performance results highlight how systematic optimization, modern hardware, and iterative engineering can unlock massive throughput gains on commodity servers.