Binary Compatibility
Binary compatibility says that you can take the program you have today and load the disk onto the new system and it will run. For people in the PC world, this has been a capability that has existed literally since PCs came out. In the early days of PCs, we would test out the level of binary compatibility that existed by running a flight simulator program on the new machine. (Though it sounds a little frivolous, this application was a pretty good test of whether or not the new system would run existing programs.)
Without binary compatibility, the older applications need to be recompiled in order to work on the new machine. A new binary (the code that actually executes when the machine runs) must be created. Aries provides for a customer who has been running HP-UX on a PA-RISC system the needed binary compatibility even though the hardware and the processor underneath has changed significantly.
Aries is a dynamic object code translator. It picks up the binary (which is also known as object code) and translates it from one microprocessor (PA-RISC) to another (Itanium). Therefore, it allows you to run your existing HP-UX software without the need to recompile it.
HP evaluated several different methods of executing PA-RISC binary modules on the Itanium architecture. The approach that HP chose, that of dynamic code translation, offered a number of customer benefits:
Dynamic code translation is transparent to the user. No effort on the part of the user is required.
Dynamic code translation can be tuned for best performance on specific Itanium processors.
The source PA-RISC binary code does not need to be modified as part of the translation process, thus preserving the original binary code.