A Bidirectional Layer7 Proxy Load Balancer with Deterministic Session Control

This paper presents a novel Bidirectional Layer7 Proxy Load Balancer (L7LB) architecture implemented using NGINX and a minimal Acceptor module. Unlike traditional TCP upstream models, which rely on unidirectional connections from client to server, the proposed design reverses the TCP session direction to achieve deterministic request-per-second (QPS) behavior and strong resilience against traffic spikes. This approach enables predictable throughput, reduced port exhaustion, and graceful degradation under high concurrency. The Layer7 Proxy architecture was verified through a proof of concept (PoC) conducted in July 2019. Performance measurements confirm scalability with multi-core CPUs and demonstrate practical advantages over conventional L7 load balancing in dynamic, service-modular environments.