adaptive VPN unblock internet

In this paper, we describe a new mechanismwhich we call an adaptive VPN that enables enterprises to selectively transport some packets from/to auser on an end-to-end VPN session and at the sametime transport other packets from/to the same useron a network-based VPN session, based on the application that is accessed by the user. This mechanismprovides enterprises the flexibility to enjoy the bene-fits of a network-based VPN for any user/applicationcombination that the enterprise is willing to entrust tothe NSP. At the same time, enterprises can transport data that requires a higher level of security usingend-to-end VPNs. This flexibility increases theacceptability of network-based VPNs to enterprises,thereby increasing the NSP's revenue opportunities.Adaptive VPN is illustrated in Figure 4