FIREWALL USING APPLICATION-LEVEL PROXY METHOD FOR CONTROLLING DATA TRANSFERS BETWEEN NETWORKS BASED ON EMBEDDED TAGS IN CONTENT DESCRIPTION LANGUAGE

A method of controlling the transfer of data between a first and a second computer network comprises parsing content description language received from the first computer network by the second computer network to determine current tag information within the content description language. A completion decision is then dynamically made based upon the current tag information. In one embodiment, the completion decision may include any of the following: full data transfer between the two networks, partial data transfer between the two networks, a deferred data transfer at a later time, or a cached data transfer. Restrictions based upon a user's age, a user's access rights, cost, system resources, and time of day may also be employed to limit the transfer of data based upon the current tag information. In a preferred embodiment, the content description language is HTML. This method may be practiced by an application level proxy that is part of a firewall system protecting the second computer network from the first.