Book Image

CASP+ CompTIA Advanced Security Practitioner Study Guide: Exam CAS-003 - Third Edition

By : Jeff T. Parker, Michael Gregg
Book Image

CASP+ CompTIA Advanced Security Practitioner Study Guide: Exam CAS-003 - Third Edition

By: Jeff T. Parker, Michael Gregg

Overview of this book

The next few years will bring a 45-fold increase in digital data and at least one-third of that data will pass through the cloud. The level of risk to data everywhere is growing in parallel and organizations are in need of qualified data security professionals to safeguard their information. The CASP+ certification validates this in-demand skillset and this book is your ideal resource for passing the exam. CASP+ meets the ISO 17024 standard and is approved by the U.S. Department of Defense to fulfill Directive 8570.01-M requirements. It is also compliant with government regulations under the Federal Information Security Management Act (FISMA). As such, this career-building credential makes you in demand in the marketplace and shows that you are qualified to address enterprise-level security concerns. The CASP+ CompTIA Advanced Security Practitioner Study Guide: Exam CAS-003, Third Edition, is the preparation resource you need to take the next big step for your career and pass with flying colors. This book provides detailed explanations of technical and business concepts that give you the background you need to apply, identify, and implement appropriate security solutions. You’ll solidify your understanding of each objective with end-of-chapter reviews. The book contains hands-on lab exercises and hundreds of practice questions to help you test your knowledge in advance of the exam. By the end of the book, you’ll have the knowledge and the confidence to ace the CASP+ certification exam.
Table of Contents (22 chapters)
Free Chapter
1
Cover
2
Acknowledgments
3
About the Authors
4
Table of Exercises
6
Assessment Test
7
Answers to Assessment Test
18
Index
19
Advert
20
End User License Agreement

Symmetric Encryption

Symmetric encryption uses a single shared key for encryption and decryption. These are known as dual-use keys, as they can be used to lock and unlock data. Symmetric encryption is the oldest form of encryption. Historical systems such as scytale and Caesar’s cipher are types of symmetric encryption. Symmetric encryption offers users privacy by keeping individuals who do not have the key from having access to the true contents of the message. Figure 1.2 shows the symmetric encryption process.

Flow diagram shows my secret file (plain text) lead to encryption, which leads to 83dg23oKvgsn… (cipher text) which in turn leads to decryption. Decryption leads to my secret file (plain text). Two keys lead to encryption and decryption.

FIGURE 1.2 Symmetric encryption process

Notice how the plain text is encrypted with the single shared key and is then transmitted to the recipient of the message, who goes through the same process to decrypt the message. The dual use of keys is what makes this system so simple, but it also introduces weakness. Symmetric encryption is fast, and with a small key it can be used to encrypt bulk data very quickly. It is also strong and difficult to break if the key is of...