On-demand video contributes a large fraction of the data traffic on mobile networks. This share is expected to increase even more drastically in the coming years. While the cellular infrastructure is continuously evolving to keep pace with this increasing demand, it is necessary to ensure that sufficient bandwidth is reserved for other latency-sensitive realtime applications like video conferencing and multiplayer video games. A tangible approach involves reducing on-demand video load on cellular networks, especially from users on the move. We see an opportunity for cellular load reduction using edge nodes based on two observations: (1) video streaming is mostly a download-only operation with sequential data access; and (2) short-range mmWave links can deliver an extremely high throughput for nearby recipients of data. The knowledge of the user's planned travel route creates opportunities for prescient prefetching and delivering the content as the vehicle passes through just in time, using mmWave devices on en route edge nodes. ClairvoyantEdge is a novel networked system infrastructure that leverages inter-edge node communication and the knowledge of users' trajectories to plan and deliver buffered video segments to the vehicles passing by. To evaluate ClairvoyantEdge, we built a comprehensive end-to-end emulation-based workflow that incorporates in situ field measurements of mmWave links into our own homegrown emulation framework. With a minuscule 0.12% coverage of a 46km2 geographical area employing 20 edge nodes distributed in that area providing short-range mmWave access to passing vehicles, we achieve an average reduction of up to 21% in cellular bandwidth usage for video downloads, using a real-world workload comprising 758 vehicles. Our results validate the promise of ClairvoyantEdge for incorporation in future edge infrastructure evolution.

ClairvoyantEdge: Prescient Prefetching of On-demand Video at the Edge of the Network

On-demand video contributes a large fraction of the data traffic on mobile networks. This share is expected to increase even more drastically in the coming years. While the cellular infrastructure is continuously evolving to keep pace with this increasing demand, it is necessary to ensure that sufficient bandwidth is reserved for other latency-sensitive realtime applications like video conferencing and multiplayer video games. A tangible approach involves reducing on-demand video load on cellular networks, especially from users on the move. We see an opportunity for cellular load reduction using edge nodes based on two observations: (1) video streaming is mostly a download-only operation with sequential data access; and (2) short-range mmWave links can deliver an extremely high throughput for nearby recipients of data. The knowledge of the user's planned travel route creates opportunities for prescient prefetching and delivering the content as the vehicle passes through just in time, using mmWave devices on en route edge nodes. ClairvoyantEdge is a novel networked system infrastructure that leverages inter-edge node communication and the knowledge of users' trajectories to plan and deliver buffered video segments to the vehicles passing by. To evaluate ClairvoyantEdge, we built a comprehensive end-to-end emulation-based workflow that incorporates in situ field measurements of mmWave links into our own homegrown emulation framework. With a minuscule 0.12% coverage of a 46km <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> geographical area employing 20 edge nodes distributed in that area providing short-range mmWave access to passing vehicles, we achieve an average reduction of up to 21% in cellular bandwidth usage for video downloads, using a real-world workload comprising 758 vehicles. Our results validate the promise of ClairvoyantEdge for incorporation in future edge infrastructure evolution. 

One question to answer the shift from the Cloud to the Edge computing paradigm is: how distributed applications developed for Cloud platforms can benefit from the opportunities of the Edge while dealing with inherent constraints of wide-area network links? Leveraging the modularity of microservice-based applications, we propose to deploy multiple instances of the same service (one per edge site) and deliver collaborations between them according to each request. Collaborations are expressed thanks to a DSL and orchestrated in a transparent manner by the Cheops runtime. We demonstrate the relevance of our proposal by geo-distributing Kubernetes resources. 

https://inria.hal.science/hal-03770492/document

Cheops, a Service to Blow Away Cloud Applications to the Edge

In edge computing, the trend is moving towards leveraging cloud native technologies and platforms such as con-tainerization and Kubernetes to manage edge applications to improve operation efficiency. Unfortunately, the supported number of nodes per cluster is only several thousand in Kubernetes which is much less than what typical far edge use cases require. In this paper, we propose KOLE, a framework that extends the upstream Kubernetes for supporting a large number of far edge nodes. It replaces the existing apiserver-to-node communication mechanism in Kubernetes with a MQTT messaging system. The MQTT broker completely offloads the overhead of keeping numerous HTTP connections for nodes in the apiserver. In KOLE, we avoid creating numerous individual objects in the apiserver by maintaining them in a cloud state cache. The cache is snapshotted periodically for disaster recovery. Overall, KOLE achieves outstanding scalability by sacrificing the manageability of having individual objects, which we believe is a reasonable trade-off for far edge use cases. The experiment results show that KOLE is scalable and can support up to one million nodes.

KOLE: breaking the scalability barrier for managing far edge nodes in cloud

Kole

Resource management for geo-distributed infrastructures is challenging due to the scarcity and non-uniformity of edge resources, as well as the high client mobility and workload surges inherent to situation awareness applications. Due to their centralized nature, state-of-the-art schedulers that work well in datacenters lack the performance and feature requirements of such applications. We present OneEdge, a hybrid control plane that enables autonomous decision-making at edge sites for localized, rapid single-site application deployment. Edge sites handle mobility, churn, and load spikes, by cooperating with a centralized controller that allows coordinated multi-site scheduling and dynamic reconfiguration. OneEdge's scheduling decisions are driven by each application's end-to-end service level objective (E2E SLO) as well as the specific requirements of situation awareness applications. OneEdge's novel distributed state management combines autonomous decision-making at the edge sites for rapid localized resource allocations with decision-making at the central controller when multi-site application deployment is needed. Using a mix of applications on multi-region Azure instances, we show that, in contrast to centralized or fully distributed control planes, OneEdge caters to the unique requirements of situation awareness applications. Compared to a centralized control plane, OneEdge reduces deployment latency by 66% for single-site applications, without compromising E2E SLOs.

Enrique Saurez

Papers

OneEdge: An Efficient Control Plane for Geo-Distributed Infrastructures