The rapid growth in the amount of data being transferred within data centres, combined with the slowdown in Moore’s Law, creates challenges for the future scalability of electronically switched data-centre networks. Optical switches could offer a future-proof alternative, and photonic integration platforms have been demonstrated with nanosecond-scale optical switching times. End-to-end switching time is, however, currently limited by the clock and data recovery time, which typically takes microseconds, removing the benefits of nanosecond optical switching. Here we show that a clock phase caching technique can provide clock and data recovery times of under 625 ps (16 symbols at 25.6 Gb s⁻¹). Our approach uses the measurement and storage of clock phase values in a synchronized network to simplify clock and data recovery versus conventional asynchronous approaches. We demonstrate the capabilities of our technique using a real-time prototype with commercial transceivers and validate its resilience against temperature variation and clock jitter.

数据中心内传输的数据量的快速增长，加上摩尔定律的放慢，给电子交换数据中心网络的未来可扩展性带来了挑战。光开关可以提供面向未来的替代方案，光子集成平台已被证明具有纳秒级的光开关时间。但是，端到端的切换时间目前受时钟和数据恢复时间的限制，通常需要几微秒的时间，从而消除了纳秒级光切换的优势。在这里，我们表明时钟相位缓存技术可以提供低于625 ps的时钟和数据恢复时间（在25.6 Gb s ^-1时为16个符号））。与传统的异步方法相比，我们的方法使用同步网络中时钟相位值的测量和存储来简化时钟和数据恢复。我们使用带有商用收发器的实时原型演示了我们技术的功能，并验证了其针对温度变化和时钟抖动的弹性。