1. A computer-implemented method for determining a unique identifier associated with a network node, comprising: using a processor to query an Internet Protocol (IP) address lookup data structure using an IP address associated with the network node, wherein the IP address lookup data structure comprises an array comprising one or more elements, an element stored at an index, the element comprising a unique identifier associated with a particular network node, the index being determined based on an IP address associated with the particular network node; returning the unique identifier associated with the network node; and performing one of: using the returned unique identifier to obtain an asset model associated with the network node; and using the returned unique identifier to determine whether the network node is a member of a category.