Patent ID: 8533478
Filing Date: 2013-09-10
Classification: G06F,H04L

Abstract:
1. A method of writing and reading redundant data comprising: writing data by storing a copy of the data, along with a timestamp that includes a signature on the copy of the data and on the timestamp, at each of a set of storage devices; reading the data by retrieving the copy of the data, the timestamp, and the signature from each of the set of data storage devices and selecting one of the copies of the data to be provided to a requestor of the data; requesting each of the storage devices of the set to certify the selected copy of the data, wherein to certify the selected copy of the data includes each of the storage devices of the set verifying that a coordinator device selected the data having a most-recent timestamp and wherein to certify the selected copy includes confirming that each copy of the data includes a signature from a different data storage device of the set of data storage devices; and provided that a proof of certification of the selected copy of the data is valid, instructing the storage devices of the set to store the selected copy of the data along with a new timestamp.