1. In a system comprising a first back-end lookup computer and a plurality of protocol computers, a method comprising: at a first of the plurality of protocol computers: receiving a plurality of DNS queries; multiplexing the plurality of DNS queries and state information associated with each of the plurality of DNS query into a first single communication; sending the first single communication to the first back-end lookup computer, wherein the first back-end lookup computer is configured to receive multiplexed DNS queries and to search a single database using the first single communication including the plurality of DNS queries that are multiplexed; receiving a second single communication from the first back-end lookup computer; retrieving a plurality of DNS responses by de-multiplexing the second single communication, wherein each of the plurality of DNS responses corresponds to one of the plurality of DNS queries; and transmitting the plurality of DNS responses; and at the first back-end lookup computer: de-multiplexing the first single communication received from the first of the plurality of protocol computers into the plurality of DNS queries; constructing a DNS response to each of the plurality of DNS queries by searching the single database using each of the plurality of DNS queries; multiplexing the DNS responses into the second single communication; sending the second single communication to the first of the plurality of protocol computers; receiving an update to the single database from the first of the plurality of protocol computers; and updating the single database using the update, wherein the update is packaged in the first single communication.