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Question 115

A software company is developing an application in which data must be encrypted with a cipher that requires the following:

✑ Initialization vector

✑ Low latency

✑ Suitable for streaming

Which of the following ciphers should the company use?

    Correct Answer: A

    The most suitable cipher for data encryption in an environment that requires an initialization vector, low latency, and is suitable for streaming is the Cipher Feedback (CFB) mode. CFB mode operates as a stream cipher, allowing data to be encrypted in real-time with low latency. It utilizes an initialization vector (IV) to seed the encryption process, ensuring the uniqueness of the ciphertext for identical plaintext across different encryption instances. This makes CFB an ideal choice for applications where continuous data streams need to be encrypted quickly and securely.

Discussion
Mr_BuCk3th34DOption: A

Cipher Feedback (CFB) is a block cipher mode that is suitable for encrypting data in a streaming context, such as when data is being transmitted over a network in real-time. It requires an initialization vector (IV) to seed the encryption process, and it has low latency, making it suitable for use in applications where low latency is important. CFB is also resistant to certain types of attacks, such as replay attacks, which can occur when an attacker captures and re-transmits encrypted data in an attempt to gain unauthorized access.

AlexJacobsonOption: A

CFB is faster than CBC (or CBC-MAC) so it is suitable for streaming. Electronic codebook doesn't use IV, so it's a wrong answer.

OneSaintOption: A

Cipher Feedback is a Stream Cipher, Initialization Vector.....yes

hidadyOption: A

A is the correct answer

xaliqOption: C

Answer C . CBC dates back to the mid-1970s, so it is fairly mature. By using CBC mode, every plaintext block is encrypted using a unique cipher. The first block is encrypted using a random Initialization Vector (IV), along with the key. The ciphertext becomes the IV for the next block of plaintext data. The following diagram shows the CBC process: CBC mode operates sequentially, which means it offers no options to improve performance by using parallel processing. Newer block ciphers offer better performance

[Removed]Option: A

Anser is A because CFB is a stream cipher unlike CBC

ukuwaiOption: A

CBC is not a stream cipher

23169fdOption: A

keyword:Streaming Cipher feedback (CFB) mode can be implemented as a stream cipher and used to encrypt individual characters. CFB is similar to OFB in that previously generated cipher text is added to subsequent streams. Because the cipher text is streamed together, errors and corruption can propagate through the encryption process

BiteSizeOption: A

Source: Verifying each answer against Chat GPT, my experience, other test banks, a written book, and weighing in the discussion from all users to create a 100% accurate guide for myself before I take the exam. (It isn't easy because of the time needed, but it is doing my diligence)

AlenKumarOption: A

Cipher Feedback(CFB) is the correct answer. Of the options provided, the most suitable cipher for the application would be Cipher Feedback (CFB) or Output Feedback (OFB). These modes of operation for the Advanced Encryption Standard (AES) are suitable for encrypting data that is streamed and use an initialization vector (IV) to ensure that the same plaintext encrypted with the same key does not produce the same ciphertext. They are also known for their low latency, as they can perform encryption and decryption in parallel.