A Wakeup Call for Internet Monitoring Systems: The Case for Distributed Triggers

There have been a number of recent proposals for distributed monitoring infrastructures. We argue that a vital missing component from these proposals is a distributed triggering mechanism, by which nodes in the system can proactively work together to maintain invariants and constraints over the system-wide behavior. Without such a triggering compo- nent, existing proposals are doomed to poor performance, high detection latency, or both. A key research challenge in building such a triggering mechanism lies in devising solutions whereby individual nodes can independently detect (and react to) violations of con- straints that are dened in terms of the aggregate behavior of nodes in the system. We discuss our early efforts in de- signing such a triggering system and the research challenges that lie ahead.