A crucial consideration in environments where data is broadcast to clients is the low bandwidth available for clients to communicate with servers. Advanced applications in such environments do need to read data that is mutually consistent aswell ascurrent. However, given the asymmetric communication capabilities and the needsof clients in mobile environments, traditional serializability-based approaches are too restrictive, unnecessary, and impractical. We thus propose the use of a weaker correctness criterion called update consistency and outline mechanisms based on this criterion that ensure (1) the mutual consistency of data maintained by the server and read by clients, and (2) the currency of data read by clients. Using these mechanisms, clients can obtain data that is current and mutually consistent “off the air”, i.e., without contacting the server to, say, obtain locks. Experimental results show a substantial reduction in response times as compared to existing (serializabil...