IPsec Virtual Private Network Fundamentals

Chapter 3. Basic IPsec VPN Topologies and Configurations

In this chapter, we will review several common deployments of IPsec virtual private networks (VPNs). We will begin by reviewing the typical site-to-site IPsec model over a dedicated circuit between two endpoints, then discuss some of the design implications as that dedicated circuit grows to include an entire routed domain. We will discuss aggregation of many site-to-site IPsec VPNs at an aggregation point, or hub IPsec router, in a standard hub-and-spoke design and extend the IPsec aggregation concept to include Remote Access VPN (RAVPN) design considerations. Figure 3-1 illustrates a loose process that may be helpful when configuring a crypto endpoint for basic IPsec operations. Though ...