Architecting Programmable Data Plane Defenses into the Network with FastFlex.

This paper is motivated by the ever increasing scale and diversity of attacks that are best handled by the network infrastructure. FastFlex builds upon recent progress, which has developed a variety of network defenses in programmable data planes, and takes this trend one step further: it aims to develop architectural support for these defenses as a first-class citizen. We envision that the network architecture would support these defenses as naturally as it does routing---as the network routes traffic end-to-end, it also turns the defenses on and off as needed for attack mitigation. We propose a key abstraction: the multimode data plane. Normally, it operates under optimal configurations computed by centralized control, but upon attacks, it performs distributed mode changes entirely in data plane for mitigation. Mixed-vector attacks would trigger co-existing modes at different regions of the network, and attacks that rapidly change would be met with equally fast mode adaptations. We sketch this vision, discuss the opportunities and challenges it involves, and present a use case on link-flooding defense.