Programmable Data-Plane Service Chaining With P4 and Virtualized Network Functions

Traditional service chaining approaches rely on external control planes, static forwarding, or CPU-based middleboxes, which limit scalability and increase latency. Programmable data planes and the P4 language introduce a new model where traffic inspection and forwarding can be executed directly in the switch pipeline. This work presents a fully functional service chaining platform based on P4 and virtualized network functions (VNFs). The system integrates a stateful firewall, a load balancer, and a monitoring function. Traffic is routed through these functions without requiring centralized orchestration or software switching. The firewall uses hashing and Bloom filters to detect flow direction and maintain state. The load balancer distributes traffic among multiple backend servers using IP Virtual Server (IPVS). The monitoring function performs passive flow analysis and exposes performance metrics. The architecture is evaluated in a Containernet environment, using HTTP and TCP experiments. The results show that the programmable data-plane approach provides efficient traffic routing, supports multiple VNFs in a chain, and collects real-time performance information.