Test and analysis of sensitive factors of SSL VPN on Kylin

SSL VPN is virtual private network using Internet Protocol (IP) tunnels to establish temporary, secure, steady end-to-end connectivity to realize the secure encrypted communication between geographically distant networks through a common shared medium such as the Internet. The performance of SSL VPN is affected by many factors ranging from the hardware to the software. Related research has presented that transport protocol and encryption algorithm are the most sensitive factors that affect the performance of SSL VPN. Based on this conclusion, this paper tested and analyzed how the performance of SSL VPN was affected by choosing different transport protocols and encryption algorithms on Kylin OS. In the experiment, two transport protocols (TCP and UDP) and four encryption algorithms (DES-EDE3, IDEA, AES, SCB2) were applied. Assessment task has found that SSL VPN on Kylin produces a lower performance values in high traffic environments for the UDP-based user applications. Meanwhile, SCB2 algorithm has the greatest effect on the throughput of SSL VPN among the algorithms above. Analysis also found that the interaction between the two most sensitive factors has the significant effect on the performance of SSL VPN.