Node Router Sensors: What just happened?

When an airliner crashes, one of the most important tasks is the recovery of the flight recorder or black box. This device gives precise and objective information about what happened and when before the crash. When an information security incident occurs on a network, it is equally important to have access to precise information about what happened to the victim machine and what it did after any compromise. A network of devices can be designed, economically constructed and managed to automatically capture and make available this type of data to information security incident handlers. In any environment, this complete record of network data comes with legal and ethical concerns regarding its use. Proper technical, legal and ethical operation must be baked into the design and operational procedures for devices that capture information on any network. These considerations are particularly necessary on a college campus, where such operations are subject to public discussion. This paper details the benefits, designs, operational procedures and controls and sample results of the use of 'Node Router Sensors' in solving information security incidents on a busy college network.