CAMGRAPH: Distributed Graph Processing for Camera Networks

With the proliferation of sensors of various kinds, especially cameras, large-scale situation awareness applications employing camera networks will become common place. These applications are inherently distributed, dynamic, interactive, run 24×7, and generate spatiotemporal events that need to be stored and retrieved in a timely manner to satisfy real-time constraints. To address these challenges, we present CAMGRAPH, a distributed graph processing system for storing and querying events and event relationships generate by camera networks. CAMGRAPH presents a simple, easy to use high-level API for developers of situational awareness applications to store new events and query existing events. Under the covers, CAMGRAPH does all the heavy lifting to efficiently handle the events generated by the camera network. CAMGRAPH uses a graph abstraction to store the events and their relationships. The CAMGRAPH graph processing system is a distributed architecture embodying heuristics for automatic repartitioning of the graph to ensure load balancing, and careful placement of vertices on the nodes of the distributed system to ensure good edge locality which is important for efficient low latency query processing. We perform controlled experiments to showcase the low latency and scalability properties of CAMGRAPH.