Security Against Corruption for Networked Storage

A computer-readable data storage medium comprising computer-program instructions executable by a processor for:

• requesting, from a computing device, a linear combination of data packets stored on a different computing device, the linear combination of data packets having been distributed to the different computing device using a network coding content distribution scheme, the linear combination of packets being initially digitally signed with respective homomorphic digital signatures to create digitally signed blocks of content, responsive to receiving the linear combination of data packets, the different node having recombined the linear combination of packets to generate corresponding new valid signatures for respective ones of the linear combination of packets from the homomorphic digital signatures;
• responsive to the requesting, receiving the linear combination of data packets from the different computing device;
• determining, for each packet of the linear combination of packets, validity of a digital signature associated with the packet using a corresponding one of the new valid signatures;
• and
• responsive to the determining, retaining only received ones of the linear combination of packets that have a corresponding valid digital signature.

A distributed computing system comprising:

• digitally signing, by a first computing device using respective homomorphic digital signatures, respective ones of a set of segmented blocks of content to create digitally signed blocks of content;
• distributing, by the first computing device using a distribution scheme, a linear combination of packets to a destination device, the linear combination of packets comprising the digitally signed blocks of content and public information used to digitally sign the respective ones of the segmented blocks;
• receiving, by a second computing device coupled to the first computing device in the distributed computing system, a linear combination of packets, the linear combination of packets comprising digitally signed blocks of content and public information used to digitally sign segmented blocks;
• recombining, by the second computing device, the linear combination of packets to compute new valid signatures as linear combinations of received homomorphic digital signatures;
• and
• wherein the homomorphic digital signatures and the public information allow a device receiving one or more packets of the linear combination of packets to verify and authenticate content associated with the one or more packets independent of secure transmission of secret keys and hash digests used to digitally sign the one or more packets.