Consider a block cipher that is used in cipher block chaining mode. Suppose that during transmission,...
Consider a block cipher that is used in cipher block chaining mode. Suppose that during transmission, Ci , the i-th ciphertext block, is corrupted. How many plaintext blocks will be affected? Answer the same question for the case of cipher feedback mode.
Homework Answers
In cipher block chaining mode we know that every cipher text block is involved in two plain text text block description i.e. its own and subsequent one so when Ci, the i-th cipher text block is corrupted only two plain text block is corrupted which is Pi and Pi +1 block.
In cipher feedback mode if Ci, the i-th cipher text block is corrupted than only two received plain text block is corrupted.
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Consider a block cipher that is used in cipher block chaining
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