An Upper Physical layer functional Split (UPS) for an Ethernet fronthaul network is modelled, and the frame delay and Frame Delay Variation (FDV) limitations are investigated. The results show that contention in Ethernet switch ports can cause an increase in the delay and FDV beyond proposed specifications for the UPS and other time-sensitive traffic types such as I/Q-type traffic. Time Aware Shaping (TAS) can significantly reduce or even remove FDV for UPS traffic and I/Q-type traffic, but it is shown that TAS design aspects have to carefully consider the transmission pattern of the contending traffic in the Ethernet fronthaul network switches. Taking into account the transmission pattern of the UPS traffic, different time allocations within TAS window sections are proposed in conjunction with both receiver and transmitterside buffering. Further, it is proven that using TAS with higher link rates for example, 10 Gbps link rates or beyond makes it possible to transport the UPS and time sensitive traffic within its specification over fronthaul fiber spans, more than 10 km length, and/or more hops as TAS can potentially eliminate any increase in the FDV of the UPS traffic.

对以太网前传网络的上层物理层功能拆分（UPS）进行了建模，并研究了帧延迟和帧延迟变化（FDV）限制。结果表明，以太网交换机端口中的争用会导致延迟和FDV的增加，超出针对UPS和其他对时间敏感的流量类型（如I / Q型流量）的建议规格。时间感知整形（TAS）可以大大减少甚至消除UPS流量和I / Q型流量的FDV，但事实表明，TAS设计方面必须仔细考虑以太网前传网络交换机中竞争性流量的传输模式。考虑到UPS流量的传输模式，建议在TAS窗口部分内结合接收器和发送器侧缓冲进行不同的时间分配。进一步，