Multiboot Specification

Node: Data comparison technique, Next: I/O restriction technique, Up: BIOS device mapping techniques

### Data comparison technique

Before activating any of the device drivers, gather enough data from similar sectors on each of the disks such that each one can be uniquely identified.

After activating the device drivers, compare data from the drives using the operating system drivers. This should hopefully be sufficient to provide such a mapping.

Problems:

1. The data on some BIOS devices might be identical (so the part reading the drives from the BIOS should have some mechanism to give up).
2. There might be extra drives not accessible from the BIOS which are identical to some drive used by the BIOS (so it should be capable of giving up there as well).