Master's thesis of Engineering: Building mobile L2TP/IPsec tunnels

This thesis proposes and implements a new and novel solution on simulators and real devices to solve the mobility problem in a VPN. The new solution adds mobility support to existing L2TP/IPsec (Layer 2 Tunneling Protocol/IP Security) tunnels. The new solution tunnels Layer 2 packets between VPN clients and a VPN server without using Mobile IP, without incurring tunnel-re-establishment at handoff, without losing packets during handoff, achieves better security than current mobility solutions for VPN, and supports fast handoff in IPv4 networks.