Next-generation networks increasingly rely on network slices - logical networks tailored to specific application requirements, each with distinct Service-Level Agreements (SLAs). Ensuring compliance with these SLAs requires continuous, real-time monitoring of end-to-end performance metrics for each slice, within a limited telemetry budget. However, we find that existing solutions face two fundamental limitations: they either lack end-to-end visibility (e.g., sketches, probabilistic sampling) or provide visibility but lack the control mechanisms to dynamically allocate monitoring resources according to slice SLAs. We address this through a formal framework that reframes slice monitoring as a closed-loop control problem, and defines the minimal data plane requirements for SLA-aware slice monitoring via a telemetry primitive contract. We then present SliceScope, a realization of this framework that combines: (1) a control strategy that dynamically allocates the monitoring resources across diverse slices according to their SLA criticality, and (2) a data-plane based on change-triggered INT that provides per-packet end-to-end visibility with tunable accuracy-overhead trade-offs, satisfying the telemetry contract. Our evaluation results on programmable switches and in large-scale simulations with a mixture of different slice types, demonstrate that SliceScope tracks critical slices up to 4x more accurately compared to static baselines, while showing that change-triggered INT outperforms alternative primitives for realizing the telemetry primitive contract.

翻译：下一代网络日益依赖于网络切片——为特定应用需求定制的逻辑网络，每个切片具有不同的服务等级协议（SLA）。为确保符合这些SLA，需要在有限的遥测预算内，对每个切片的端到端性能指标进行持续、实时的监控。然而，我们发现现有解决方案面临两个根本性局限：要么缺乏端到端可见性（如草图法、概率采样），要么虽提供可见性但缺乏根据切片SLA动态分配监控资源的控制机制。我们通过一个形式化框架解决此问题，该框架将切片监控重新定义为闭环控制问题，并通过遥测原语契约定义了SLA感知切片监控所需的最小数据平面要求。随后，我们提出SliceScope——该框架的一个实现，它结合了：（1）一种控制策略，可根据各切片SLA的关键性动态分配跨不同切片的监控资源；（2）基于变化触发式INT的数据平面，以可调节的精度-开销权衡提供逐数据包的端到端可见性，满足遥测契约要求。我们在可编程交换机上的评估结果及混合不同切片类型的大规模仿真表明，与静态基线相比，SliceScope对关键切片的跟踪精度最高提升4倍，同时证明变化触发式INT在实现遥测原语契约方面优于其他备选原语。