A virtual private network (VPN) uses the internet to provide secure (encrypted) communication between remote locations or users within the same network. There are two types of VPN: IPSec and SSL.
IPSec is the most commonly-used protocol to establish secure connections between networks and connect hosts in virtual private networks.
Within IPSec, there are several subsidiary protocols that perform specific functions, such as the following:
- Authentication Header (AH): This provides proof-of-origin for IP packets, protecting them against replay attacks.
- Encapsulation Security Protocol (ESP): This protocol provides the origin authenticity, integrity, and confidentiality of the transmitted data.
- Security Association (SA): This is the set of algorithms used to encrypt and authenticate the transmitted data. Because SA is associated with data...
