OREANDA-NEWS. August 23, 2012. NEC Corporation (NEC; TSE: 6701) has developed high-speed, light-weight encryption technology to provide secure communications for information exchanged via sensor devices, reported the press-centre of NEC.

A large volume of information is now transmitted via sensor devices, such as surveillance cameras and GPS terminals, and some of this "big data" faces issues with privacy. To ensure the protection of privacy, communications data need to be encrypted between the sensor device and the server, and between sensor devices.

For secure communication involving big data, communications data encryption for sensor devices is carried out via small devices equipped with dedicated encryption circuits (hardware), or in software processing by microcomputers. Communications data encryption for servers is also performed in software processing. Communications via sensor devices must support all of these implementation environments and provide light-weight, high-speed and secure encryption algorithms.

Since AES, which is currently used as a standard encryption algorithm, has a large circuit size, it is difficult to incorporate a dedicated encryption device into small sensor equipment. The current light-weight encryption algorithm that enables encryption in small circuits also poses challenges in lower processing speeds in software.

NEC's newly developed encryption algorithm enables high-speed processing in all environments, including small, dedicated encryption devices, and software processing on microcomputer servers. Its light weight places it in the world's smallest class for hardware circuits and calculation resources that include memory usage in microcontrollers.

Key features of this newly developed technology are as follows:

High-speed encryption algorithm in all implementation environments from hardware to software
NEC enhanced the generalized Feistel structure (*3) used for the current encryption algorithm, and features lightness, high-speed and security. NEC only provides this in four-bit processing so that high-speed processing can be achieved in software as well as hardware.
Compared with the current representative encryption algorithms used exclusively for small devices, this technology achieves an equivalent processing speed for ASIC (*4), which is the integrated circuit for specific applications, and features 4.5 times faster software processing in a small microcomputer. It also provides a processing speed of 3.76 Gbps (2.5 times that of AES implemented in the C language) for CPUs used on the server (2.8 GHz clock).

Operating on world's smallest scale calculation resources
When creating a dedicated encryption device using ASIC, comparing the circuit size with the present AES encryption (secret key length: 128-bit) there is a reduction to about 1,800 gates, or about one-sixth (based on the assumption of a standard circuit configuration). When encryption processing is performed through software running on all-purpose microcontrollers (8/16/32-bit), this technology can operate on the world's smallest scale calculation resources of less than 1,000 bytes in ROM capacity and less than 500 bytes in RAM capacity.

High-level security equivalent to existing encryption methods
NEC confirmed that this technology has sufficient resistance, on a par with existing cryptanalytic methods such as the AES security evaluation method. This ensures a high level of security irrespective of the hardware or software.

NEC continues its research and development of this technology in order to drive business related to sensor systems and solution businesses using big data.