Enhancing P4-Based Network Emulation Fidelity Through a Lightweight Virtual Time System and Application Evaluation
针对P4网络仿真中BMv2交换机在高流量和大规模场景下性能下降导致的保真度问题，提出集成轻量级虚拟时间系统到Mininet中，通过时间膨胀因子优化仿真速度，评估显示能准确仿真更大网络且开销小，对网络应用开发者有用。
P4 serves as a programming language for configuring flexible and programmable network data planes, facilitating the development of custom protocols and programmable switches, and driving innovation in software-defined networking and network function virtualization. While the Linux container based network emulator, Mininet, coupled with the BMv2 software P4 switch, is widely used for rapid prototyping of P4-based applications, BMv2’s diminished performance raises fidelity concerns under high traffic and large network scenarios. In this paper, we introduce a lightweight virtual time system integrated into Mininet with BMv2 to enhance fidelity and scalability. By applying a time dilation factor (TDF) to interactions between containers and the physical machine, we optimize the emulated P4 network’s perceived speed from the application processes’ perspective. System evaluation demonstrates accurate emulation of significantly larger networks under high loads with minimal system overhead. We showcase our system’s utility through two network applications: an emulation of a TCP SYN flood attack and an ECMP load balancer. Evaluating against a production-grade software switch, Open vSwitch, and a physical testbed, we highlight the virtual time system’s improvement in temporal fidelity despite the observed performance degradation in BMv2 software switches.