We introduce an improved IPv6 access system for small scale network with IPv4 upstream, which combines Tunnel Broker and programmable router. Tunnel Broker system is unfit for the small network such as a home or a small office network, because its requirement of global IPv4 address. Further more, Tunnel Broker system can’t react to the network performance changing quickly. To deal with the defects, we design a new system based on VPN to avoid the requirement of global IPv4 address, and we improve our system by adding the performance measurement framework. We integrate all the functions into a programmable router. Experiments confirms that our system can steadily and easily connect to IPv6 network without any operation. The robustness and effectiveness of our system is further demonstrated when the network performance changes. Our system will switch to a better route based on the performance measurement framework.