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Course: Computers and the Internet > Unit 4

Lesson 5: Data encryption techniques
Computing
Computers and the Internet
Online data security
Data encryption techniques
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Symmetric encryption

Google Classroom

Problem

Herman came up with a scheme for encrypting messages to send to his best friend:
For each letter in the message, he replaces the letter with a picture that represents that letter.
He needs to share the encryption key with his friend before they can decrypt his messages.
What would be the best key for this symmetric encryption scheme?
Choose 1 answer: