How Does Tunneling Work?
The VPN tunnel is like a temporary bubble tube that is created specifically to allow you and another party to communicate. Your conference is kept secret through the exchange of encryption keys between your end of the tunnel and the recipient's end. As a result, the contents of your communication are hidden from view and are only made visible once they have reached their destination and been unlocked by the recipient's key. Once your session ends, the bubble disappears.
Types of Tunneling Protocols
Point-to-point tunneling protocol (PPTP) — Found built into most versions of the Windows operating system, this is one of the most popular protocols. The communications system it uses establishes a direct connection that enables streams of data to be exchanged. It guarantees that the data you transmit will be delivered and received in the same order that you sent it.
Layer 2 Tunneling Protocol (L2TP) — An extension of the point-to-point tunneling protocol, it marries the best aspects of 2 other tunneling protocols, Microsoft’s PTPP and L2F from Cisco Systems. Its main components are a mechanism called an Access concentrator that terminates a call and the network server that ensures that your data reaches its destination securely. Because this protocol enables data packets to be processed at a location set apart from where the circuit is terminated, security is enhanced. You also never need to worry about paying long-distance charges with this protocol.
IP Security (IPsec) — This is actually a suite that incorporates the best of several tunneling protocols. When combined with Point-to-Point tunneling or layer2 tunneling protocols, it provides a secure transaction of data within a virtual private network tunnel. By verifying each packet of data you are sending and converting it into a secret code that can only be unlocked by the recipient, this protocol is excellent at protecting your valuable data.
IPsec can be used to promote communication between users, networks, and even firewalls. Because it is placed deep in the network layer of the system, it is more flexible than many other protocols and does not require that your applications be specifically designed to use it. Only this protocol protects all application traffic over an IP network. It provides ways for data to be mutually authenticated by both parties at the start of a session, as well as ways to convert data into secret codes and to unencrypt it.
Secure Socket Tunneling Protocol (SSTP) — This protocol provides for secure passage of data between a network server and a remote terminal, bypassing any firewalls or web proxies it might contact along the way. To make this happen, it uses HTTPS protocol and is often the go-to choice if the other popular tunneling protocols fail to perform effectively.
OpenVPN — This protocol enables data to pass from one entity to another by establishing an encrypted UDP (User Data Protocol) connection between the source and the destination. Whereas many other protocols are only compatible with certain operating systems, OpenVPN will work with any of them.
Secure Sockets Layer Virtual Private Network (SSL VPN) —This protocol can be used with a standard web browser. Unlike IPsec, the end user does not need to install specialized software. This protocol gives remote users access to web applications, servers and internal networks. To utilize this, a person uses a web browser to connect to one or more VPN devices. The SSL protocol is used to encrypt the data as it travels to and fro in the tunnel.
As you can see, VPN tunneling protocols vary in their characteristics and qualities, and as encryption technology evolves, so will these protocols. Regardless of which you choose, you can be sure that the data you are sending or receiving will be safe from hacking or other kinds of interference from outside sources.