VPN(virtual Private network) provide a cost-effective means of connecting an organization and its partners when compared to the cost of a private network. A VPN provides a secure channel link over the Internet between project partners. This paper gives a brief introduction of fundamentals and implementations of the VPN, the comparison between characteristics and technologies of the traditional and based on IPsee VPN. Through studying IPsec, we presented a method of designing hub-and-spoke VPN system based on IPsec, which has been used for automobile collaborative design.