Joe Is Exchanging Encrypted Email with Another Party

question 622

Multiple Choice

Joe is exchanging encrypted email with another party. Joe encrypts the initial email with a key. When Joe receives a response, he is unable to decrypt the response with the same key he used initially. Which of the following would explain the situation?

• A) An ephemeral key was used for one of the messages
• B) A stream cipher was used for the initial email; a block cipher was used for the reply
• C) Out-of-band key exchange has taken place
• D) Asymmetric encryption is being used

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Definitions:

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The real value of money, reflecting the quantity of goods or services that one unit of money can buy, inversely related to the level of prices in the economy.

Producer Price Index

An economic measure reflecting the average rate of change in the prices at which domestic producers sell their goods over time.

Consumer Price Index

A tool that analyzes the weighted mean prices for an assortment of consumer necessities, such as healthcare, transportation, and food items.

Consumer Price Index

An index that measures the weighted average price of a group of consumer essentials, including transportation, medical care, and food.