Abstract: A system for limiting unauthorized access to a network comprises an IP assignment system and an access system. The IP assignment system includes a random number generator capable to generate a random number between a minimum and maximum leasing time; and an IP assignment engine, communicatively coupled to the generator, capable to receive, from a client, a request for an IP address, assign an IP address to the client, randomly determine, using the generator, a leasing time for the IP address, and send, to the client, a packet that includes the IP address and leasing time. The access system includes a packet monitoring engine capable to receive a packet sent to a client, the packet including an IP address, a random leasing time and a renewal window; and an access engine, communicatively coupled to the packet monitoring engine, capable to enable the client to access a network and terminate access to the network if a renewal packet is not received during the renewal window.

Abstract: An information distribution device selection system capable of selecting one information distribution device that is logically closest from the user communication terminal among a plurality of information distribution devices on inter-connected communication networks is disclosed.