Which of the following encryption modes require the management of an IV? Select one or more: a. CFB b. GCM c. CTR d. OFB e. ECB f. CBC

a. CFB d. OFB f. CBC

Explanation:

The inputs to the encryption processes of the CBC, CFB, and OFB modes require the management of an IV (Initialization Vector) and denoted IV. The IV is used at an initial step in the encryption process of a message and in the corresponding decryption of the message.

For the CBC and CFB modes, the IV for a particular execution of the encryption process must be unable to be predicted, and for OFB mode, unique IVs must be used in each of the execution of the encryption process.