This session presents a methodical technique for troubleshooting Dynamic Multipoint VPN (DMVPN) networks. The session starts with a short overview of DMVPN functionality and then concentrates on a four-layer troubleshooting methodology. These four layers are IP infrastructure layer (peer connectivity), IPsec encryption layer (IPsec/ISAKMP), GRE/NHRP layer (NHRP), and the VPN layer (IP routing protocols). Explicit troubleshooting examples with solutions are shown that are based on the most common DMVPN design and implementation issues as seen by Cisco Technical Assistance Center (TAC) engineers. This session is for designers, managers, and troubleshooters of extended corporate DMVPNs and for service providers deploying these services.