Grapevine was developed at Xerox by the same research group the developed the Ethernet. Among other things, Grapevine provides a distributed, replicated database, implemented by servers residing at various locations around the internet. Clients can query, add new entries or modify existing entries in the database. The Grapevine database maps character string keys to entries called RNames. Each server registers the transport address at which its service can be accessed and every instance of an interface is registered as an individual entry.
Individual entries map instances to their corresponding transport addresses.
The type of an interface, which consists of a list of individual RNames . Group entries contain RNames that point to servers providing the service having that group name. Once the interface has been registered with Grapevine, it can be imported by the client. Grapevine insures that both an individual and a group entry has been established for the exported service. The server stub then records information about the instance in an internal export table .