Abstract: A method and system are provided for improving accuracy in an inventory containing assets associated with a network. In one embodiment, a method is provided for updating information pertaining to computer devices in a group of computer devices connected to a specified network. Each device sends packets through at least one router in a set of interconnected routers, and each packet contains an element uniquely identifying its sending computer device. The method includes maintaining an inventory identifying at least some of the computer devices as assets (of an entity associated with the network. The method further includes acquiring data from ARP caches that are respectively located within the routers. The acquired cache data is processed to detect all of the identifying elements contained therein that respectively identify computer devices of the group. A database is constructed from information in the cache data that pertains to respective detected identifying elements.