Abstract: A method of encrypting digital content, the method is executed by at least one data processor and comprises selecting one or more segments of said digital content, duplicating said selected segment or segments, creating a plurality of copies of each segment and performing different encryption on said different copies.

Abstract: A system for network content monitoring and control, comprising: a transport data monitor, connectable to a point in a network, for monitoring data being transported past said point, a signature extractor, associated with said transport data monitor, for extracting a derivation of said data, said derivation being indicative of content of said payload, a database of preobtained signatures of content whose movements it is desired to monitor, and a comparator for comparing said derivation with said preobtained signatures, thereby to determine whether said payload comprises any of said content whose movements it is desired to monitor. The monitoring result may be used in bandwidth control on the network to restrict transport of the content it is desired to control.

Abstract: A method for making an anonymous computerized commerce transaction involving the delivery of digital merchandise including the steps of sending first sensitive information from a first entity to a first intermediate entity, processing the first sensitive information at the first intermediate entity, creating first non-sensitive information operable to approve the transaction by the first intermediate entity, sending the first non-sensitive information to a third entity operable to perform the transaction, performing the transaction at the third entity, and transferring the digital merchandise to the first entity via a delivering entity including information operable to deliver the digital merchandise to the first entity without revealing the first sensitive information to the third entity.

Abstract: A method for secure distribution of digital content to an untrusted environment, comprising the steps of: constructing a relatively trusted environment within the untrusted environment; constructing at least two digital inputs, the digital inputs are operable in order to reproduce the digital content; transferring digital media to the relatively trusted environment such that each of the inputs is transmitted via a different path, and combining the inputs in order to reproduce the digital content.

Abstract: A method for secure distribution of digital content, the method including the steps of dividing a unit of digital content into at least first and second portions, storing the first portion on a first computerized apparatus, digitally watermarking the second portion, and combining the first portion and the digitally watermarked second portion, thereby forming a watermarked version of the digital content.

Abstract: A system for external monitoring of networked digital file sharing to track predetermined data content, the system comprising: at least one surveillance element for deployment over said network, said surveillance elements comprising: surveillance functionality for searching said digital file sharing and identification functionality associated with said search functionality for identification of said predetermined data content, therewith to determine whether a given file sharing system is distributing said predetermined data content.