iSACA Cybersecurity Fundamentals Certification Practice Exam

What is a major disadvantage of symmetric key encryption?

1. It is less complicated

2. Difficulty in key distribution

3. It can sign electronic documents

4. Lower processing power usage

The correct answer is: Difficulty in key distribution

The major disadvantage of symmetric key encryption lies in the difficulty of key distribution. In symmetric encryption, both the sender and receiver must have access to the same secret key, which means this key must be securely exchanged before any encrypted communication can occur. This exchange creates challenges, especially in environments where numerous parties need to communicate securely, as it becomes increasingly complex to manage a unique key for each pair of users. If the key falls into the wrong hands during distribution, the security of the communication is compromised. In contrast, less complicated systems and lower processing power usage are not inherently disadvantages; they are often seen as advantages of symmetric encryption. Additionally, while symmetric encryption can provide confidentiality, it does not facilitate the signing of electronic documents, which is associated with asymmetric encryption methods. This highlights the importance of understanding key distribution concerns when implementing symmetric encryption securely.