Substrate-Aware Connectivity Support for Scalable Overlay Service Construction

Internet overlay services may exhibit poor performance when their designs ignore the topology and link properties of the underlying Internet substrate. Various service-specific techniques have been proposed to select good overlay links and thus enhance the performance. In this paper, we explore the model of providing a substrate-aware overlay structure management layer to assist the construction of large-scale wide-area Internet services. To this end, we propose Saxons, a distributed software layer that dynamically maintains an efficient mesh structure connecting overlay nodes. Saxons provides connectivity support with three performance goals: low overlay latency, low hop-count distance, and high overlay bandwidth. Services built on top of this layer can utilize the mesh structure while achieving high performance. Furthermore, Saxons targets large-scale self-organizing services which adds scalability and stability requirements into our design. This paper describes the design of Saxons and services that can take advantage of it. Our simulation-based evaluations demonstrate Saxons’ effectiveness in terms of structure quality, stability, and overlay connectivity. To illustrate the usage of Saxons, this paper also presents the design of a Saxons-based high-bandwidth overlay route discovery service.