Bøger af Kian-Lee Tan

In data publishing, the owner delegates the role of satisfying user queries to a third-party publisher. As the servers of the publisher may be untrusted or susceptible to attacks, we cannot assume that they would always process queries correctly, hence there is a need for users to authenticate their query answers. This book introduces various notions that the research community has studied for defining the correctness of a query answer. In particular, it is important to guarantee the completeness, authenticity and minimality of the answer, as well as its freshness. We present authentication mechanisms for a wide variety of queries in the context of relational and spatial databases, text retrieval, and data streams. We also explain the cryptographic protocols from which the authentication mechanisms derive their security properties. Table of Contents: Introduction / Cryptography Foundation / Relational Queries / Spatial Queries / Text Search Queries / Data Streams / Conclusion

Welcome to the Second International Conference on Mobile Data Management (MDM2001). The conference serves as a forum for the exchange of technical ideas and research results in the areas of mobility and database management. This year, we have a very exciting program for MDM2001. Many quality papers were submitted to the conference. All of the submitted papers were - viewed by at least three PC members. Due to the limitations of the program schedule as well as the desire to organize the conference using a single track format, we selected only 18 papers for full presentation at the conference. As a result many excellent papers could not be accepted. The papers chosen for presentation span a large range of topics, from n- work protocol issues up to the semantics of mobile applications. The common theme of all these papers is their recognition of the central role played by data managementtechniques in the developmentof the emerging worldof mobile and wireless applications. We have loosely organized these papers into six areas: 1. DATA MANAGEMENT ARCHITECTURES, 2. CONTENT DELIVERY, 3. DATA BROADCASTING, 4. CACHING AND HOARDING, 5. COPING WITH MOVEMENT, 6. NETWORKS AND SYSTEMS ISSUES In addition to the researchtrack, we havesought to broaden the scope of the conference with an industrial session as well as poster presentations. Overall, the program strikes a comfortable balance between applied and theoretically oriented papers.

Focuses on mechanisms that can provide unobstructed access to networks. This work provides a review of advances on energy-efficient data delivery protocols, wireless channel bandwidth utilization, broadcasting and cache invalidation strategies for clients with long disconnection time. It also compares and evaluates some of the promising schemes.