Clearinghouse activity for geodata obtaining in the World Wide Web
Digital geodata are precious resources both for a nation and for a person. With the rapid development of networks such as the Information Highway and WWW, widely distributed geodata stimulate users' needs. There is now an urgent appeal for the publication of the geodata. Because of the abundant information on the Internet, geodata may be difficult to discover and to use. In this article, we introduce a clearinghouse activity which can search for the proper geodata based on meta data using Z39.50 protocol. We also present some basic concepts about it and its working mechanism. We then discuss some key technologies to implement a clearinghouse node and ways to improve the service as well.