A Composable Emulation Framework for Whitebox Switches#

Congcong Miao (Tencent), Xianneng Zou (Tencent and Tsinghua Shenzhen), Chuwen Zhang (Tsinghua), et al., with Ang Chen (University of Michigan)

• Why: As switches disaggregate into vendor-mixed modules (data plane, control plane, optics), monolithic firmware emulators stop matching reality — and config errors slip through to production. This is the first emulation framework built for that composed world.
• What: "MirSwitch," a composable whitebox-switch emulation framework deployed in Tencent's production network; operators used it to troubleshoot 97.5% of 203 issues in a recent year, with 2.2x better forwarding-emulation performance.
• How: An adaptor-centric design that stitches together diverse emulator modules for data plane, control plane, and peripherals (including optical components), reconciling differing interface contracts across modules so mixed-vendor compositions can be emulated faithfully before deployment.
• Where applicable: Operators building disaggregated/whitebox switches from multiple vendors; the 97.5%-of-issues production statistic is unusually strong validation for an emulation paper.