Virtual private network using L2TP/IPSec

Before we look at the tunneling protocols, we need to learn a little about encryption  there are two main types of encryption: asymmetric and symmetric. Encryption is the process of taking data in plaintext format and transferring it to ciphertext, a format that makes it unreadable. Encryption is covered in depth later in this book; the two main types are:

  • Asymmetric encryption: Certificates are used for encryption and it uses two keys: a private key and a public key. The public key is used for encrypting data and the private key is used for decrypting data.
  • Symmetric encryption: Uses only one key, called either the private key or shared key, for both encrypting and decrypting data, making it much ...

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