Cisco Cyber Security Practice Exam

As the number of users increases, which encryption type faces key management challenges?

1. Symmetric

2. Asymmetric

3. Obfuscation

4. Homomorphic

The correct answer is: Symmetric

Symmetric encryption relies on a single shared secret key for both encryption and decryption processes. As the number of users increases, the key management becomes increasingly challenging because every pair of users needs a unique key to ensure secure communication. For instance, if there are ten users, a complete shared key approach would require a total of 45 unique keys (one for each pair of users). This growing complexity makes it difficult to distribute, store, and manage these keys securely. In contrast, asymmetric encryption uses a pair of keys (public and private), allowing users to share their public keys while keeping their private keys secure. This model simplifies key management significantly since each user only needs to keep their private key safe, and they can share their public key widely without risk. Obfuscation and homomorphic encryption also have their own specific functions and use cases, but they do not face the same level of key management challenges as symmetric encryption when scalability and user growth is a concern.