arch.gif illustrates the description given in the previous paragraphs under the heading Architecture.
arch.gif shows three side-by-side areas representing the three-tier model.
The left area contains an image of a Personal Computer or Work station, and a Personal Digital Assistant (PDA) labelled Web Browser. There is a bottom label, Client tier.
The middle area shows a generic computer box representing a web server. It is labelled iSQL*Plus Server. There is a bottom label, Middle tier.
The right area shows a generic drum representing a database or database server. It is labelled Oracle9i. There is a bottom label, Database tier.
The two Web Browsers on the left are linked to the iSQL*Plus Server in the middle by connecting lines labelled HTTP, TCP/IP. The iSQL*Plus Server in the middle is linked to the Oracle9i database on the right by a connecting line labelled Oracle Net.