Algorithmic design of the globe wide-area location service

We describe the algorithmic design of a worldwide location service for dist ributed objects. A distributed object can reside at multiple locations at t he same time, and offers a set of addresses to allow client processes to co ntact it. Objects may be highly mobile like, for example, software agents o r Web applets. The proposed location service supports regular updates of an object's set of contact addresses, as well as efficient look-up operations . Our design is based on a worldwide distributed search tree in which addre sses are stored at different levels, depending on the migration pattern of the object. By exploiting an object's relative stability with respect to a region, combined with the use of pointer caches, look-up operations can be made highly efficient.