This guide covers the concepts, principles, and practices for designing, deploying, managing, and operating IPsec VPNs. It introduces how to use IPsec VPNs to protect network communications, including an overview of IPsec VPN security. The guide also discusses current standards and practices for IPsec VPNs, including the design, implementation, evaluation, and monitoring of IPsec VPN security. This guide is intended for individuals and organizations responsible for designing, deploying, managing, and operating IPsec VPNs.