Welcome to Symmetric vs. Asymmetric Encryption

Now you will learn why Encryption is a big part of Network Security!

**In this Video we will: **

• Present an overview of the two methods of encryption in use today.
• Describe and illustrate Symmetric and Asymmetric encryption.
• Explain the advantages and disadvantages of both methods of encryption.
• At the end of this lecture you will understand the difference between Symmetric and Asymmetric encryption.

**What is Encryption? **

Encryption is the process of encoding data to prevent unauthorized access.

There are two forms of encryption in common use today. Symmetric and Asymmetric.

With Symmetric Encryption

• There is only one key
• The same key encrypts and decrypts the data

Here is a video describing Symmetric key encryption

Let’s say you want to send me an email. You encrypt the email using your secret key, you send me the key.

I receive the email and decrypt it using the same key.

The problems with Symmetric Encryption

• You must keep the key secret
• The key will need to be transferred to the other party
• Susceptible to attack – If a third party steals the key they will be able to decrypt the data and read the message.

Advantages of Symmetric encryption

• Very fast – The process of Symmetric Encryption is much faster than Asymmetric Encryption.

Asymmetric Encryption

• Consists of two keys (pairs)
• The public key can be shared, given away – Sent in an email, posted on a web site.
• The private key cannot be shared, keep it private
• The private key is the only key that can decrypt data encrypted with the public key.
• If someone encrypts data with the public key, the only way data could be decrypted is with the private key. That is why the private key must be kept private.

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