Lawrence Berkeley National Laboratory

When diagnosing network problems, it is often desirable to have a view of traffic inside the network. In this paper we describe an infrastructure for passive monitoring that can be used to determine which segments of the network are the source of problems for an application data stream. The monitoring hosts are relatively low-cost, off-the-shelf PCs. A unique feature of the infrastructure is secure activation of monitoring hosts in the core of the network without direct network administrator intervention.