Packet structure and communications protocol for GML data transmission and system thereof

摘要

PURPOSE: A packet structure for a GML(Geography Markup Language) data transmission and reception and its communication method and system are provided to accurately and quickly transfer a GML data to a user by converting three-dimensional geographical data into the GML data and compressing it. CONSTITUTION: Upon receiving a geographical information data request from a user, a GML transfer server is loaded a GML data from a map adapter server(201). The GML transfer server compresses the GML data in a main memory(203). The GML transfer server processes the GML data in a packet format, adds an overhead to the packet, and transfers it to a communication network(205). The communication network judges whether to transfer the data packet(207). If the data packet is an effective one, the communication network transfers the data packet to a mobile terminal. The mobile terminal receives the data packet and stores it in an internal buffer(209), and extracts the GML data from the packet(211). The mobile terminal checks whether the extracted GML data or packet itself is effective(213). If the data is effective, the mobile terminal releases the data if the data has been compressed, and displays the GML data in a display unit of the mobile terminal for a user to view a three-dimensional geographical information(215).