Which of the following is the MOST important consideration for determining the operational life of...

The most important consideration for determining the operational life of an encryption key is the volume and sensitivity of data protected by the key. The operational life of an encryption key is the period of time during which the key can be used securely and effectively to encrypt and decrypt data. The operational life of an encryption key depends on various factors, such as the length and complexity of the key, the strength and speed of the encryption algorithm, the number and frequency of encryption operations, the number of entities involved in communication, and the number of digitally signed documents in force. However, among these factors, the volume and sensitivity of data protected by the key is the most critical, as it affects the risk and impact of a potential compromise or exposure of the key. The higher the volume and sensitivity of data protected by the key, the shorter the operational life of the key should be, as this reduces the window of opportunity for an attacker to access or misuse the data.

References: CDPSE Review Manual, 2021, p. 117