OUTSIDE ACCESS TO COMPUTER RESOURCES THROUGH A FIREWALL

摘要

A firewall isolates computer and network resources inside the firewall from networks, computers and computer applications outside the firewall. Usually, a firewall allows for an inside user or object to originate connection to an outside object or network, but does not allow for connections to be generated in the reverse direction; i.e. from outside in. The disclosed invention provides a special "tunnelling" mechanism, operating on both sides of a firewall, for establishing such "outside in" connections when they are requested by certain "trusted" individuals or objects or applications outside the firewall. The mechanism includes special tunnelling applications, running on interface servers inside and outside the firewall, and a special table of "trusted sockets" created and maintained by the inside tunnelling application.