Join Doug Winnie for an in-depth discussion in this video Symmetric and asymmetric keys, part of Computer Science Principles: The Internet.
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- Simple keys like the Caesar Cipher…require that both sides of the message agree…on what the key is and will be applied…to the message before it's sent.…This is called Symmetric Security.…This works fine in situations where…you have exchanged that information in private,…but in the case of the internet, it wouldn't work.…If I want to establish a security key with a server,…If I want to let that server know what the key is,…I would need to send it to the server…over an unsecure connection.…
So anyone could read what the security key is.…And then potentially use it…to intercept messages and crack them later on.…The trick to make this work is to have two keys.…One that the sender uses to encrypt and send information,…but is not able to be used to decrypt it.…The other is a key that is only on the receiver's end,…and can be used to decrypt…all the information that it receives.…This is called asymmetric security.…
So as a sender encrypts and sends information,…even if someone is able to find a key,…it can't be used to decrypt it,…
This course is the second in our Computer Science Principles series, designed around the AP Computer Science Principles (CSP) curriculum. It is a great foundation for anyone, at any age, to prepare for careers in technology and computer science. Understanding basics like the Internet will help you understand the interplay between hardware, software, data, networks, and the people that use them.
- How the Internet was born
- Sending and receiving information on a computer
- IP addressing
- DNS, routers, and packets
- Identifying web servers with URLs
- HTTP and HTML
- Encrypting data that's sent over the Internet