Page 661 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

Exam Essentials

Be able to explain the differences between multitasking,
multithreading, multiprocessing, and multiprogramming.
Multitasking is the simultaneous execution of more than one

application on a computer and is managed by the operating system.
Multithreading permits multiple concurrent tasks to be performed
within a single process. Multiprocessing is the use of more than one
processor to increase computing power. Multiprogramming is similar
to multitasking but takes place on mainframe systems and requires

specific programming.
Understand the differences between single-state processors

and multistate processors. Single-state processors are capable of
operating at only one security level at a time, whereas multistate
processors can simultaneously operate at multiple security levels.

Describe the four security modes approved by the federal
government for processing classified information. Dedicated
systems require that all users have appropriate clearance, access

permissions, and need to know for all information stored on the
system. System high mode removes the need-to-know requirement.
Compartmented mode removes the need-to-know requirement and
the access permission requirement. Multilevel mode removes all three
requirements.

Explain the two layered operating modes used by most
modern processors. User applications operate in a limited

instruction set environment known as user mode. The operating
system performs controlled operations in privileged mode, also known
as system mode, kernel mode, and supervisory mode.

Describe the different types of memory used by a computer.
ROM is nonvolatile and can’t be written to by the end user. The end
user can write data to PROM chips only once. EPROM/UVEPROM
chips may be erased through the use of ultraviolet light and then can

have new data written to them. EEPROM chips may be erased with
electrical current and then have new data written to them. RAM chips