Designing infrastructures that give untrusted third- parties (such as end-hosts) control over routing is a3C promising research direction for achieving flexible and efficient communi- cation. However, serious concerns remain over the deployment of such infrastructures, particularly the new security vulnerabilities they introduce. The flexible control plane of these infrastructures can be exploited to launch many types of powerful attacks with little effort.

In this paper, we make several contributions towards studying security issues in forwarding infrastructures. We present a general model for a forwarding infrastructure, analyze potential security vulnerabilities, and present techniques to address these vulnerabilities. The main technique that we introduce in this paper is the use of simple, light-weight, cryptographic constraints on forwarding entries. We show that it is possible to prevent a large class of attacks on end-hosts, and bound the flooding attacks that can be launched on the infrastructure nodes to a small constant value. Our mechanisms are general and apply to a variety of earlier proposals such as \I3, DataRouter and Network Pointers.