Abstract: In accordance with one example, a method for comparing data units is disclosed comprising generating a first digest representing a first data unit stored in a first memory. A first encoded value is generated based, at least in part, on the first digest and a predetermined value. A second digest representing a second data unit stored in a second memory different from the first memory, is generated. A second encoded value is derived based, at least in part, on the second digest and the predetermined value. It is determined whether the first data unit and the second data unit are the same based, at least in part, on the first digest, the first predetermined value, the first encoded value, and the second digest, by first processor. If the second data unit is not the same as the first data unit, the first data unit is stored in the second memory.

Abstract: In accordance with one example, a method for comparing data units is disclosed comprising generating a first digest representing a first data unit stored in a first memory. A first encoded value is generated based, at least in part, on the first digest and a predetermined value. A second digest representing a second data unit stored in a second memory different from the first memory, is generated. A second encoded value is derived based, at least in part, on the second digest and the predetermined value. It is determined whether the first data unit and the second data unit are the same based, at least in part, on the first digest, the first predetermined value, the first encoded value, and the second digest, by first processor. If the second data unit is not the same as the first data unit, the first data unit is stored in the second memory.

Abstract: A hash-optimized backup system and method takes data blocks and generates a probabilistically unique digital fingerprint of the content of each data block using a substantially collision-free algorithm. The process compares the generated fingerprint to a database of stored fingerprints and, if the generated fingerprint matches a stored fingerprint, the data block is determined to already have been backed up, and therefore does not need to be backed up again. Only if the generated fingerprint does not match a stored fingerprint is the data block backed up, at which point the generated fingerprint is added to the database of stored fingerprints. Because the algorithm is substantially collision-free, there is no need to compare actual data content if there is a hash-value match. The process can also be used to audit software license compliance, inventory software, and detect computer-file tampering such as viruses and malware.

Abstract: In accordance with one example, a method for comparing data units is disclosed comprising generating a first digest representing a first data unit stored in a first memory. A first encoded value is generated based, at least in part, on the first digest and a predetermined value. A second digest representing a second data unit stored in a second memory different from the first memory, is generated. A second encoded value is derived based, at least in part, on the second digest and the predetermined value. It is determined whether the first data unit and the second data unit are the same based, at least in part, on the first digest, the first predetermined value, the first encoded value, and the second digest, by first processor. If the second data unit is not the same as the first data unit, the first data unit is stored in the second memory.

Abstract: In accordance with one example, a method for comparing data units is disclosed comprising generating a first digest representing a first data unit stored in a first memory. A first encoded value is generated based, at least in part, on the first digest and a predetermined value. A second digest representing a second data unit stored in a second memory different from the first memory, is generated. A second encoded value is derived based, at least in part, on the second digest and the predetermined value. It is determined whether the first data unit and the second data unit are the same based, at least in part, on the first digest, the first predetermined value, the first encoded value, and the second digest, by first processor. If the second data unit is not the same as the first data unit, the first data unit is stored in the second memory.

Abstract: A hash-optimized backup system and method takes data blocks and generates a probabilistically unique digital fingerprint of the content of each data block using a substantially collision-free algorithm. The process compares the generated fingerprint to a database of stored fingerprints and, if the generated fingerprint matches a stored fingerprint, the data block is determined to already have been backed up, and therefore does not need to be backed up again. Only if the generated fingerprint does not match a stored fingerprint is the data block backed up, at which point the generated fingerprint is added to the database of stored fingerprints. Because the algorithm is substantially collision-free, there is no need to compare actual data content if there is a hash-value match. The process can also be used to audit software license compliance, inventory software, and detect computer-file tampering such as viruses and malware.

Abstract: A method is provided to facilitate the detection of file tampering, such as a computer virus, on a computer. In one example, a digital fingerprint is generated for each file on the computer using a substantially collision-free algorithm. The digital fingerprints of the computer files are compared with digital fingerprints of the computer files generated when the files were previously saved. If the digital fingerprint of that file differs from the digital fingerprint generated when that file was previously saved, a computer virus or other tampering may exist on the file.

Abstract: A method is provided to audit license restrictions of a computer program in an enterprise computing environment. In one example, a digital fingerprint is generated of at least one file in the computer program using a substantially collision-free algorithm, and a digital fingerprint is generated for each file on each computer in the enterprise using the substantially collision-free algorithm. The digital fingerprints from the enterprise files are compared with the digital fingerprint of the computer program file, and the number of fingerprint matches is counted. Another method is provided for inventorying a computer program in an enterprise computing environment. In examples of both methods, a file may be divided into data blocks and a digital fingerprint may be generated for each data block.

Abstract: In accordance with one example, a method for comparing data units is disclosed comprising generating a first digest representing a first data unit stored in a first memory. A first encoded value is generated based, at least in part, on the first digest and a predetermined value. A second digest representing a second data unit stored in a second memory different from the first memory, is generated. A second encoded value is derived based, at least in part, on the second digest and the predetermined value. It is determined whether the first data unit and the second data unit are the same based, at least in part, on the first digest, the first predetermined value, the first encoded value, and the second digest, by first processor. If the second data unit is not the same as the first data unit, the first data unit is stored in the second memory.

Abstract: In accordance with an example of an embodiment of the invention, a method for comparing a first unit of data stored in a first storage system and a second unit of data stored in a second storage system is provided. The method comprises generating a first digest that represents the first unit of data, generating an initial value associated with the first unit of data, and deriving an encoded value using the first digest and the initial value. The method further comprises transmitting the encoded value from the first storage system to the second storage system, generating a second digest that represents the second unit of data, and deriving a decoded value using the second digest to decode the encoded value. The method also comprises transmitting the decoded value from the second storage system to the first storage system, and determining whether the first unit of data and the second unit of data are duplicates of one another by comparing the decoded value and the initial value. Systems are also disclosed.

Abstract: A method and system are provided for comparing data stored in a first storage system with corresponding data stored in a second storage system. In one implementation, the first system generates a random value associated with a respective data block P, and transmits to the second system an identifier associated with the data block P, and the random value. The second system generates a first digest representing a data block B, uses the first digest to encode the random value, producing a first encoded value, and transmits the first encoded value to the first system. The first system generates a second digest representing the data block P, uses the second digest to encode the random value, producing a second encoded value, and compares the first and second encoded values. If the two encoded values are equal, the data block B is a duplicate of the data block P. If the two encoded values are not the same, the data blocks are different.

Abstract: A hash-optimized backup system and method takes data blocks and generates a probabilistically unique digital fingerprint of the content of each data block using a substantially collision-free algorithm. The process compares the generated fingerprint to a database of stored fingerprints and, if the generated fingerprint matches a stored fingerprint, the data block is determined to already have been backed up, and therefore does not need to be backed up again. Only if the generated fingerprint does not match a stored fingerprint is the data block backed up, at which point the generated fingerprint is added to the database of stored fingerprints. Because the algorithm is substantially collision-free, there is no need to compare actual data content if there is a hash-value match. The process can also be used to audit software license compliance, inventory software, and detect computer-file tampering such as viruses and malware.

Abstract: A hash-optimized backup system and method takes data blocks and generates a probabilistically unique digital fingerprint of the content of each data block using a substantially collision-free algorithm. The process compares the generated fingerprint to a database of stored fingerprints and, if the generated fingerprint matches a stored fingerprint, the data block is determined to already have been backed up, and therefore does not need to be backed up again. Only if the generated fingerprint does not match a stored fingerprint is the data block backed up, at which point the generated fingerprint is added to the database of stored fingerprints. Because the algorithm is substantially collision-free, there is no need to compare actual data content if there is a hash-value match. The process can also be used to audit software license compliance, inventory software, and detect computer-file tampering such as viruses and malware.