An address reporting device receives a query for an address corresponding to a machine name of a machine on a first network, from a second network. The address reporting device accesses name servers so as to determine whether or not the address corresponding to the machine name designated in the...http://www.google.co.uk/patents/US5815664?utm_source=gb-gplus-sharePatent US5815664 - Address reporting device and method for detecting authorized and unauthorized addresses in a network environment 
