SPATIAL MAP DATA SHARE AND DISSEMINATION SYSTEM BASED ON
DISTRIBUTED NETWORK SERVICES
D. Zhang1, L. Ailong2, W. Ling2, Y. Xuewei2, C. Tao2
1 - School of Electronics and Information Engineering, Xi’an
JiaoTong University; Xi an research institute of sueveying and mapping, Map and
GIS, Xi an, China
2 - Xi an research institute of sueveying and mapping, Map
and GIS, Xi an,
navgrid@163.com
Spatial Map Data (SMD), with some
characteristics such as mass data, multi-scales, universality and discrete
distribution, is suitable to be processed in the network environment with
distributive, sharing, self-adaptive, heterogeneous and expansive features. The
Map Data Network Dissemination System (MDND) for
disseminating SMD to remote users through network is presented. Firstly, SMD,
associated metadata and network resource nodes described as a graphic form are
defined. The relations between SMD and network resources are established. After
giving formalized definition to MDND, SMD dissemination framework and a series of
distributed CORBA services, conditions input methods based on three querying
conditions are presented. MDND is implemented in the basis of metadata
integrated querying service and SMD route-pointed service. Compared with the
modes of CORBA service, FTP and Direct Copy, results show that SMD
dissemination can be achieved effectively by the proposed system. The transfer
performances of CORBA services mode is almost equal to direct Copy , obviously
better than FTP evidently, and approaches to the biggest transfer rate more
quickly and dependents on data amount weakly.