that connects hundreds of thousands of telecommunication networks and creates an “internetworking” framework.
2.5.2. Basic Component of Internet
According to Aronoff 1989, the main frame of internet is web services or distributed services. The term services here refers
to component services; that is, components with certain functions can be downloaded and reassembled data, including data input,
storage, retrieval, management, manipulation, analysis, and output.
According to Peng and Tsou 2003 there four major components of Internet such are the client, Web server with application server, and data server
Figure 2.6. The client servers as user interface for user interface for users to interact with the Internet Programs. The Web server receives client requests,
serves static Web pages, and invokes application servers. The application server manages server transactions, securities, and load balance. The data server serves
geospatial and non-spatial data and provides data access and management through a Structured Query Language SQL.
Figure 2.6. Basic components in Internet Peng and Tsou, 2003
2.5.2.1. The Client
According to Peng and Tsou 2003 the client is a place for users to interact with objects and analysis functions in Internet. It is also a place for
Internet uses graphic user interface to construct the client, Internet usually relies on the Web and Web add-ons as its client. A typical Web interface with HTML
and forms is a simple client of Internet. But this simple HTML-based client has very limited user interactively. .
Furthermore, Peng and Tsou 2003 state that alternative clients who used Web add-ons have been developed to increase user interactively and helps users to
interact directly with objects. There also include dynamic HTML and client-side applications such as plug-ins or help programs, Java applets or Java beans, and
ActiveX controls. Dynamic HTML uses client-side scripting like JavaScript or VBScript to make the plain HTML dynamic.
2.5.2.2. Web Server
The second component in Internet is comprised of the Web server. The Web server is also called the HTTP server; its major function is to respond to
requests from Web browsers via HTTP. There are several ways for the Web server to respond to client requests: 1 by sending existing HTML document or
ready-made map images to the client, 2 by sending Java applets or ActiveX controls to the Web client, and 3 by passing requests to other programs and
invoking other programs such as CGI that cloud process the queries Peng and Tsou, 2003.
2.5.2.3. Application Server
When the Web server passes client requests to other programs, it requests services from application servers. An application server can be a glue program or
middleware that connects the Web server and server-side applications such as a map server. An application server acts as a translator or connector between the
Web server and the map server. The major functions of an application server include establishing, maintaining, and terminating the connection between the
Web server and the map server; interpreting client requests and passing them to the map server, managing the concurrent requests and balancing loads among map
server and data server; and managing the state, transaction, and security Peng and Tsou, 2003.
2.5.2.4. Data Server
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