Artemis

Abstract

Today, Internet service deployment is typically implemented with server replication at multiple locations for the purpose of load balancing, failure tolerance, and user experience optimization. Domain name system (DNS) is responsible for translating human-readable domain names into network-routable IP addresses. When multiple replicas exist, upon the arrival of a query, DNS selects one replica and responds with its IP address. Thus, the delay caused by the process of DNS query including the selection of replica is part of the connection setup latency. In this paper, we proposed Artemis, a practical low-latency naming and routing system that aims at reducing the connection setup latency by eliminating the DNS query latency while keeping the ability to perform optimal server (replica) selection based on user-defined rules. Artemis achieves these goals by integrating name resolution into the transport layer handshake. Artemis allows clients to calculate locally the IP address of a Service Dispatcher, which serves as a proxy of hosting servers. Service Dispatchers forward the handshake request from a client to a server, and the response is embedded with the server's IP address back to the client. This enables clients to connect directly with servers afterward without querying DNS servers, and therefore eliminates the DNS query latency. Meanwhile, Artemis supports user-defined replica selection policies. We have implemented Artemis and evaluated its performance using the PlanetLab testbed and RIPE Atlas probes. Our results show that Artemis reduces the connection setup latency by 26.2% on average compared with the state-of-the-art.