Operational Layer 3 Topology

Knowledge of the currently active network topology is useful for a number of tasks that include identifying sources of poor application service quality and proactive network fault detection. We present the concept of the operational topology of an Internet Protocol (IP) network and a technique for discovering it. This lightweight technique does not make use of any proprietary information and is thus highly suitable for use in a multi-vendor environment. We also discuss uses of the operational topology, and present some operational topology metrics and visualization.