icrosoft supports!
             it within Windows. As implied by the name, this protocol is typically used in end-to-end tunneling applications. IPSec was developed by the Internet Engineering Task Force as a security mechanism to protect IP packets. It is commonly used in both end-to-end and node-to-node applications. The third, L2TP, came out of a mix of the PPTP and another less known protocol developed by Cisco - Layer 2 Forwarding. This combination is frequently used in node-to-node applications. Encryption. VPN's also use encryption technology to ensure the confidentiality of data as it passes over the Internet. The encryption technologies used in VPNs are the same ones used in any other networking situation where data is encrypted. The choice of encryption technology is generally not an issue, since most equipment vendors support the major encryption choices on the market. A decision must be made in the area of key size, however. The general idea is that the larger the key is, the more difficult it i!
             s to crack the code and therefore the more secure the data will be. Typically 40-bit to 128-bit sized keys are used in commercial applications. The correct key size depends on many factors. The most obvious ones are network security and data confidentiality. But keys can be scaled, even on session by session basis, so a smaller key may be used for e-mail, while larger keys are used for confidential payroll data for example. Access Rights and Authentication. Administering access rights and authentication privileges for not only VPNs but also the more common remote-access servers (RAS), can prove to be quite a task. This burden has eased somewhat with the Remote Authentication Dial In User Server, known as RADIUS. RADIUS is commonly used and supported by most remote-access equipment vendors, and now VPN equipment companies are supporting the use of a RADIUS server for user authentication. The main attraction of RADIUS is that it allows manage...