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Century #Media Literacy
Skills
Video based question Scan the
QR Code
Watch the video and answer the question.
Which wireless media exchanges data over a short distance
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LAB ACTIVITY Century #Technology Literacy
Skills
Visit your computer lab and perform the following actions:
▶ Explore the Internet to learn about different networks and their functions.
a. Create a presentation based on the information gathered, incorporating relevant pictures as
well.
b. Present your presentation to your class.
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#Computational Thinking
Century
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Skills
For transmitting our data over a network in a safe and secure manner, various encryption
techniques are used to convert our plain text message into cipher text. For this conversion,
different techniques are used. Some of them are explained below:
Substitution Technique
In this technique, we simply replace the letters in our message with other letters or symbols.
One of the simplest substitution techniques is the Caesar Cipher which was developed by Julius
Caesar. In this technique, each letter of the plain text is replaced by the letter three places ahead
of it. Therefore, to decrypt the cipher text, the letter of cipher text is replaced by letter three
places before it.
Example:
Plain text: Today is Sunday
Cipher text: wrgdb lv vxqgdb
We have simply replaced each letter of the plain text with the letter three places ahead of it.
Transposition Technique
In this technique, the identity of the letters remains the same but their positions are changed to
create the cipher text.
Networking Concepts 23

