Performance analysis of L2TP tunneling through simulation.

摘要

The use of Virtual Private Network (VPN) technologies is a hot topic in the networking industry. L2TP is a new VPN protocol, which is becoming popular. The thesis investigates the behavior and performance of L2TP protocol in different cases by simulation. First, the categories of VPNs, and the components of L2TP and its implementation for VPN use are reviewed and discussed. A simulation model of L2TP tunneling (i.e., the establishment of control connection) is constructed for performance analysis purpose. The simulation is performed on the Network Simulator (ns) environment developed at Berkley. For each simulation experiment, confidence intervals are computed. The L2TP performance for different scenarios is investigated in the research. According to the performance analysis results, the packet retransmission feature in L2TP is a major factor that has a strong impact on the system performance. In order to improve the performance, a new adaptive retransmission algorithm is proposed. The simulation results show that the proposed algorithm can notably improve the L2TP performance.