IPsec's Role in Network Security: Past, Present, Future

What is this term IPsec that I keep hearing, and reading about? IPsec stands for Internet Protocol Security. Simply put, IPsec is a set of open standard protocols that govern the secure, private exchange of data across public networks, such as the Internet. It was developed by the Internet Engineering Task Force (IETF), and explained primarily in RFC 2401-2412. IPsec works on Layer 3, the Network layer of the Open Systems Interconnection 7-layer networking model. By running on Layer 3, IPsec is able to function transparently to applications running on Layer 7; the applications do not require any knowledge of IPsec in order to use it. IPsec is used to create tunnels for Virtual Private Networks (VPN), and also provide confidentiality, authenticity, and integrity of data through use of encryption algorithms. Combined with Internet Key Exchange (IKE), IPsec users can exchange keys, authenticate one another, and securely tunnel encrypted data between peers.