On Problem for Aggregate Node Selection for Unstructured Overlay Networks

With the success of the peer-to-peer systems, there is an emerging trend to develop an aggregation service that can provide global information about these distributed and decentralized overlays. Existing aggregation protocols have focused on providing an efficient and cost effective solution to compute aggregates. In this paper, we are interested to search the node based on an aggregate query over rapidly changing data e.g., to seek a node with minimum/maximum workload in the network. Solution to such queries can benefit number of applications such as, node-ranking, reputation building, resource scheduling, etc. Here we propose a novel protocol to solve such queries. Our proposed protocol is reactive and pull-based in nature. It intrinsically builds and manages a routing table which routes aggregate query to the desired node in the system. We evaluated our protocol for accuracy, efficiency and communication cost through detailed simulations. We also discuss effects of an explicit routing table management scheme and show that this explicit scheme causes our protocol to work better in presence of churn and node failures.