Web Enabling Your HP 3000

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HP’s JDBC driver can be deployed in three different architectural models: two-tier, three-tier
thin client, and three-tier ultra-thin client.
Two-tier Model
In the two-tier architecture, the database and Web server are placed on the same machine as the
JDBC applet. The JDBC applet, JDBC API, and JDBC driver client either are preinstalled on the
client systems or downloaded from the Web server. Applications can run as an applet or as a
program on another machine. The most common use would be for applets that are served from
a HP e3000 web server.
Three-tier thin-client Model
It is often undesirable to have the database and the Web server on the same machine. The three-
tier thin-client model allows for physical separation of the database and Web server. A thin Java
proxy, installed on the Web server, routes the IP address to the database server. The JDBC API
and JDBC client are downloaded along with the JDBC applet from the Web server, or middle
tier. This architecture allows developers to make use of downloadable applets, access data, and
separate data processing from a heavily loaded Web server.
JDBC
Driver
JDBC
Client
Java
Application/
Applet
IMAGE/SQL
ALLBASE/SQL
Intranet/
Internet
HP e3000
Apache Web Server
DB Server
Client
Browser
• JDBC Driver Manager
• JDBC Driver Client
Two-tier Model
JDBC
Driver
JDBC
Client
Java
Application/
Applet
IMAGE/SQL
ALLBASE/SQL
Intranet/
Internet
HP e3000
DB Server
Web Server
• Java Proxy
Client
Browser
• JDBC Driver Manager
• JDBC Driver Client
Java
Proxy
Three-tier Thin-client Model