When it comes to information technology, cryptography plays a huge role in securing information in its different status. Various technical applications use cryptography on a daily basis, such as disk encryption, email security, and communication. VPNs are one of them. By definition, a VPN is a logical network between two sites. The traffic of VPNs is encrypted.
In encryption, we have the following two modes:
- Link encryption: In this mode, all the information is encrypted, and the message should be decrypted in every hop. In this case, the router should decrypt the message so it knows the routing information, encrypt it again, and forward it to the next hop.
- End-to-end encryption: In this mode, shown here, the information in the required headers is not encrypted so the routers, for example, don't need to decrypt them, because the routing information is...
