Edge computing is considered a key paradigm for supporting real-time applications over 5G networks, as hosting applications at the network edge can substantially reduce delays. A significant fraction of real-time applications over 5G are expected to be highly mobile applications. However, one challenge with hosting mobile applications on the network edge is ensuring that users continue to get low latency as they move across different locations. This requires the support to handover clients to different edge sites with negligible application delays. However, many edge applications are stateful and can experience significant downtime during state migration over 5G. This paper addresses the problem of enabling stateful mobile edge applications in 5G networks. We first identify the key architectural issues and then propose a new system design, EdgeWarp, that mitigates delays during mobility through proactive application state migration. To enable this, we extend the existing edge data stores with the design of a novel two-step application state synchronization protocol, that leverages the early prediction of the target edge host. Additionally, EdgeWarp prioritizes the handover of latency-sensitive edge applications by communicating their latency requirements to the 5G control plane at the beginning of a data session. Our evaluation with real edge applications shows up to a 15.4x reduction in application downtime under mobility. We have made our anonymized code publicly accessible here.

翻译：边缘计算被视为支持5G网络实时应用的关键范式，因为在网络边缘托管应用能显著降低延迟。预计5G网络中相当大比例的实时应用将是高移动性应用。然而，在网络边缘托管移动应用面临的一个挑战是：如何确保用户在不同地点移动时仍能持续获得低延迟体验。这需要支持将客户端无缝切换至不同边缘站点，且应用延迟可忽略不计。但许多边缘应用具有状态保持特性，在5G网络中进行状态迁移时可能经历显著的服务中断。本文致力于解决5G网络中实现有状态移动边缘应用的问题。我们首先剖析了关键架构问题，进而提出新型系统设计EdgeWarp，通过主动式应用状态迁移来缓解移动过程中的延迟。为实现这一目标，我们在现有边缘数据存储架构基础上，设计了一种新颖的两步式应用状态同步协议，该协议利用对目标边缘主机的早期预测机制。此外，EdgeWarp通过数据会话开始时向5G控制平面传递延迟敏感型边缘应用的延迟需求，优先保障此类应用的切换过程。基于真实边缘应用的评估表明，该系统在移动场景下最高可减少15.4倍的应用中断时间。我们已将匿名化代码公开于此。