CISSP考试指南笔记：7.3 物理安全

As any other defensive technique, physical security should be implemented by using a layered approach.

It is also important to have a diversity of controls.

This defense model should work in two main modes: one mode during normal facility operations and another mode during the time the facility is closed.

Facility Access Control

Access control needs to be enforced through physical and technical components when it comes to physical security.Having personnel within sensitive areas is one of the best security controls because they can personally detect suspicious behavior.

Access control points can be identified and classified as external, main, and secondary entrances.

Locks

Locks are inexpensive access control mechanisms that are widely accepted and used. They are considered delaying devices to intruders.

Padlocks can be used on chained fences, preset locks are usually used on doors, and programmable locks (requiring a combination to unlock) are used on doors or vaults.

Mechanical Locks

Two main types of mechanical locks are available: the warded lock and the tumbler lock. The warded lock is the basic padlock. It has a springloaded bolt with a notch cut in it.

The tumbler lock has more pieces and parts than a ward lock.

The three types of tumbler locks are the pin tumbler, wafer tumbler, and lever tumbler. The pin tumbler lock, is the most commonly used tumbler lock.

Wafer tumbler locks (also called disc tumbler locks) are the small, round locks you usually see on file cabinets.

Combination locks, of course, require the correct combination of numbers to unlock them.

Cipher locks, also known as programmable locks, are keyless and use keypads to control access into an area or facility.

The following are some functionalities commonly available on many cipher combination locks that improve the performance of access control and provide for increased security levels:

• Door delay
• Key override
• Master keying
• Hostage alarm