Overlook: A Scalable Name Service on an Overlay Network: "This paper presents Overlook, a scalable fault-tolerant name service that is built on top of a P2P overlay routing network (Pastry). The basic motivation behind the paper is that existing scalable name services like DNS cannot be suited to applications like Herald, an Internet-scale event notification service, where a) updates have to be made globally visible in seconds, and b) flash crowd (sudden surge in the popularity of one or a few names) is a common occurrence This is because existing name services rely on fairly static sets of data replicas and client-side caches. Overlook tries to address these issues by allowing dynamic addition and deletion of data replicas in response to varying popularities of events."