Ricoh GR-C1 Series Service Training page 75

This function lets users select safer encryption algorithms,
AES256bit and SHA-2.
Slide 75
AES256bit
The Advanced Encryption Standard (AES) is a symmetric-key encryption
standard adopted by the U.S. government. AES is also adopted by NESSIE in
EU and CRYPTREC in Japan.
There are 3 types of AES, and each of these ciphers has a 128-bit block size,
with key sizes of 128, 192 and 256 bits, respectively. DES, the previous
encryption standard, has a 56-bit key size, so AES with a 256-bit key size is
much safer than DES.
SHA-2
Secure Hash Algorithm-2 (SHA-2) is a set of cryptographic hash functions
designed by the National Security Agency (NSA).
SHA-2 has 224, 256, 384, and 512 bit hashes. Since SHA-2's hashes are longer
than SHA-1 (160 bits), SHA-2 is safer than SHA-1. Ricoh basically adopts the
256-bit hash.
Security
Enhanced Encryption
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GR-C1 Training
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