Efficient XML data placement schemes over multiple mobile wireless broadcast channels

Broadcasting is one of the basic ways to access XML data via mobile wireless networks. In these networks, XML data are disseminated over a wireless broadcast channel and mobile clients can connect to this channel via portable devices and receive the XML data they need. To date, various indexing methods have been proposed to broadcast the XML data over mobile wireless broadcast networks, each of which attempts to reduce the latency and energy consumption of mobile devices in processing the different types of XML queries. Most of the proposed indexing methods use only a single wireless broadcast channel for XML data dissemination. Due to the sequential data access over a wireless broadcast channel, the access time to retrieve the desired XML data over a broadcast channel is longer if the length of generated XML data stream is large. This paper proposes two new XML data placement schemes to disseminate the XML data over multiple wireless broadcast channels by partitioning the XML data stream into several partitions and placing them into multiple wireless broadcast channels. The goal of both of which is a further reduction of the access time during the process of XML querying over the broadcast channels. According to the experimental results, the proposed XML data placement schemes have achieved the goal of further reducing the access time, especially when the size of XML document to be disseminated is large.