BLAKE2 is an optimized version of the SHA-3 finalist BLAKE that is faster than using the MD5 algorithm on Intel x86_64 CPUs. Target applications according to its developers are cloud storage, revision control tools, software distribution, host-based intrusion detection, and digital forensics.
While BLAKE2 is faster, its developers don't believe they have cut any corners in terms of security. "We do not think that this superior software performance comes at a cost of reduced security. We argue that much of the extensive security analysis performed on BLAKE during the SHA-3 process applies to BLAKE2 and shows no cause for concern about BLAKE2's security."
BLAKE2 software is implemented as a basic single-threaded linear mode along with optimized versions for 32-bit architectures, SIMD/multi-core processors, Merkle-Tree applications, and for message integrity checking. "I'm particularly keen on the SIMD/multicore variant, a parallelized mode named "BLAKE2*p", because almost all modern CPUs — even a lot of the cheap and power-efficient 32-bit ARM chips — come with efficient SIMD features. It looks like it will be possible to have 4-way or 8-way parallelized BLAKE2*p which are many *times* as efficient as MD5, on both short files and long files. Once we've finished porting, measuring, and experimenting with the different modes of BLAKE on different machines, we intend to write a "b2sum" command-line tool, which we hope will eventually replace "md5sum" in the unix user's toolset."
More information on BLAKE2 can be found from the announcement made on Friday to the cryptography mailing list.
The BLAKE2 project site is blake2.net.