Patent ID: 8108362

Claim:
A method of automatically verifying content distributed over a network at a node in the network, the method comprising: receiving, at the node comprising a processor, a content description for a piece of content published by a publisher node, the content description comprising a content identifier, a publisher identifier, publisher authorisation information and content checking information, wherein the publisher authorisation information comprises an identifier for an authorising body; checking, at the node comprising the processor, the integrity of the content description; checking, at the node comprising the processor, the validity of the content description, wherein checking the validity of the content description comprises: accessing a certificate revocation list issued by the publisher; confirming that the content description is not included on the certificate revocation list; and confirming that the publisher authorisation information is valid, wherein confirming that the publisher authorisation information is valid comprises: accessing a certificate revocation list issued by the authorising body; confirming that the publisher identifier is not included on the certificate revocation list; and when both the integrity and validity checks are passed, storing the content description at the node comprising the processor.