Chapter 16 - Configuring Virtual Private Networking

Abstract

Virtual private networks (VPNs) securely tunnel traffic between two sites over a public network such as the Internet. VPNs are commonly used to connect branch offices, mobile users, and business partners. Connecting private networks or hosts by securely tunneling through a public network infrastructure has both commercial and practical applications. VPNs can connect branch offices, mobile users, and business partners. VPNs ensure confidentiality and authentication. VPNs provide a number of solutions, including economical connectivity between offices (using site-to-site VPNs) and the ability to provision connections quickly. Remote access VPNs provide connectivity for mobile workers or telecommuters, allowing them to securely gain access to their home network, regardless of where they are or how they connect. The PIX firewall supports both site-to-site and remote access VPNs using IPsec. VPNs can be very complicated, and a single connection might be implemented using a combination of many protocols that work together to provide tunneling, encryption, authentication, access control, and auditing. This chapter shows how to configure VPNs on the PIX firewall. It configures site-to-site VPNs using IPsec and IKE with preshared keys and digital certificates. The PIX firewall can act as a concentrator for terminating Cisco software VPN clients for remote-access VPNs.