Keys to the Kingdom

Chapter 3

Master-Keyed Systems

Chapter Outline

 Introduction

 How Master-Keying Works

 Attacking Master-Keyed Systems

 Other Methods of Master Key Compromise

 Defending Against This Attack

 Maison-Keying

 Summary

Introduction

Most residential locks and virtually all locks purchased at local hardware stores are designed to operate with a single key. That is, only one particular bitting (or combination of cuts on the blade of the key) will allow the plug to turn and cause the lock to open. If you wish to endow additional people with the ability to enter a door when it is equipped with such a simple lock, you simply make a copy of the key. If you have multiple doors on a single building and they are all operated by this key, you are effectively ...