Patent ID: 8312270

Claim:
A method of requesting an IP address within a computer network having a security policy, said method comprising: receiving a request at a DHCP server to provide an IP address for an end-user computer within said computer network; consulting a blacklist database to determine if an identification of said end-user computer is present in said blacklist database, wherein the presence of said identification indicates that said end-user computer has previously been identified as not being compliance with said security policy of said computer network; determining that said identification of said end-user computer is not present in said blacklist database without undertaking an analysis of whether or not the end-user computer is actually in compliance with said security policy of said computer network; returning to said end-user computer an IP address and a special lease time shorter than would normally be assigned, wherein the special lease time is based upon a value for a number of times that the end-user computer has requested an IP address from the DHCP server, wherein the returned IP address provides full access privileges to said computer network; subsequently to the returning, probing said end-user computer to determine that the end-user computer is actually in compliance with said security policy of said computer network; and upon expiration of the special lease time, assigning another IP address with a lease time longer than the special lease time, wherein the another IP address provides full access privileges to said computer network.