LN architecture

LN supports a three-tier architecture that consists of a display tier, an application tier, and a database tier. The display tier provides presentation services for user interaction. The application tier consists of the LN application virtual machine and the application objects. The database tier includes the LN database driver and a third-party RDBMS product that acts as the database server. The following figure shows the LN architecture.

The emphasis of this document is the LN database driver, which is the interface between the LN applications and the RDBMS server. The database driver translates database requests from the LN application virtual machine to RDBMS-specific SQL requests that the driver sends to the database server. After the database server retrieves the requested information, the database driver then passes the data back to the LN application virtual machine.

To put the functions of the database driver into perspective, the following figure shows the three tiers of the total LN architecture: