Application Research of Mobile Database Model Based on Ad Hoc Network

Mobile database is a kind of distributed database which is able to support mobile computing. For traditional mobile database model, there are some problems in Ad hoc network such as significant increase in the number of transaction conflicts, in communication costs, etc. Therefore, it is necessary to improve the traditional mobile database model. The paper aims at proposing algorithms of data synchronization and transaction redo etc. to enable mobile host to get access to the database efficiently and correctly. The experimental results show that the new mobile database model has good stability. 1. Preface With the development of network technology, information technology and database technology, mobile application has gradually changed people's life and work. However, as a main support of mobile application -- mobile database is able to meets the needs of getting the information that one needs anytime and anywhere. That is to say a new era has opened up and it would have gradual impact on us in every aspect. Traditional mobile database model mainly includes server, mobile support node and mobile host. The traditional mobile database has the following problems: the location of the mobile node is not fixed, the network communication is not symmetrical, and disconnections of the network occur frequently, the storage capacity and the processing ability are limited. However, the network based on traditional mobile database model has a large number of basic communication facilities such as base stations, mobile switching centers, etc., and most of them have been built around the city. Therefore, it is not necessary to consider too much about the effects of environment. As a multi-hop, centerless, self-organizing wireless network, Ad hoc network is adopted mostly because the environment or other factors are not conducive to laying infrastructure or the infrastructure has been damaged. In reality, one of the typical applications of Ad hoc network is for the investigation teams to perform field missions, to help disaster relief, and mine surveying, etc. In Ad hoc network, in view of the reasons such as limited capacity of energy and storage of the mobile host, limited bandwidth, and frequent disconnections with the master server, etc., it will bring about a lot of problems to apply the traditional database model to Ad hoc networks, it is necessary to improve the traditional mobile database model to accommodate Ad hoc network. Many experts have done in-depth study on mobile database, including Mallikharjuna Rao, N. Naidu, etc. who have applied fuzzy database to mobile database model, thus it solved the problem of uncertain data storage, improved the performance of mobile database model; Le Gruenwald, Shankar M. Banik, who also provides the methods of