April 2002
Intermediate to advanced
816 pages
20h 56m
English
The simplest software targets low-level hardware. Creating such software involves “writing to the bare metal.” This can be rather difficult and cumbersome, but it gives the best potential performance and flexibility. Typically, such coding occurs using assembly language targeted at a specific CPU's instruction set. Unfortunately, this makes software-enforced security nearly impossible due to complexity constraints.
One of the many benefits of an operating system is that it provides security mechanisms not easily provided in small, low-level applications. For example, an operating system defines the notion of user accounts with different privileges so that some users can be restricted from ...