Better Privacy by Server Pushing Instead of Client Pulling

To protect user privacy in an increasingly mobile world, this paper proposes a shift from client-driven data requests to a server-push model in which providers localcast information keyed to a geographic area. Instead of users constantly broadcasting their identity and location to access services, servers use broadcast disks to continuously transmit information — such as flight status, off-airport message relay, or location-specific offers — to anyone within range. This lazy identification strategy lets "silent" clients filter the broadcast locally to find what they need, transmitting only when a transaction strictly requires it. The paper grounds the approach in established technologies — XML for service composition, public-key encryption and pseudonyms for selective targeting and identity protection — and develops an airport scenario showing how a person can assemble communication, productivity, and retail services through composition while withholding identity and location from most of the providers involved. Written in 2004, the paper anticipates several architectural concerns now central to data sovereignty and privacy-preserving system design.