About the architecture of iSeries, all the applications interact with the specialized layer called TIMI Layer (Technology Independent Machine Interface). This layer in turn interacts with the LIC and LIC will interacts with Hardware. When compared with the rest of the server class all the application software's interact with the hardware directly.
Technology Independent Machine Interface translates application programs and OS instructions into Licensed Internal Code.
Licensed internal code (LIC), also called system licensed internal code, is software that interacts directly with the AS/400 hardware. LIC typically performs the following functions:
- Storage management
- Pointer and address management
- Program management
- Expectation and event management
- Data management
- I/O management
- Security management
LIC often stored on read-only chips. To update the LIC, read-only chips must be replaced