Passive Assessment of Signal Relays Amongst Bystanders

Techniques for discovering a network using a sensor installed in the network, where the network is communicatively coupled to an external network by a router, are presented. The techniques can include: determining, automatically and by the sensor, a network address of the router; detecting, automatically and by the sensor, a network address of a client in the network; assessing, automatically and by the sensor, that the client in the network is actively communicating on the network; communicating, by the sensor, with the network address of the router; and participating, by the sensor, in communications on the network by emulating the network address of the client and by using the network address of the router.