What is Equihash

Equihash is a Proof-of-Work algorithm.It is based on a computer science and cryptography concept called the Generalized Birthday Problem.
This is an optimized C++ implementation of Equihash, the memory-hard Proof-of-Work with fast verification.Equihash is an asymmetric proof-of-work algorithm based on a computationally hard generalized birthday problem, which requires a lot of memory to generate a proof, but is instant to verify. Equihash is adapted as the PoW in Zcash a public implementation of the cryptocurrency protocol Zerocash. It is possible to use Equihash in TLS as a client puzzle.

Equihash has two parameters: N (width in bits) and K (length), which determine the complexity of the underlying problem and thus the memory and time complexity of the Equihash PoW. The underlying hash function is Blake2b, but any collision-resistant hash function would work too.

If Bitcoin is like http for money, Zcash is https. Zcash offers total payment confidentiality, while still maintaining a decentralized network using a public blockchain. Unlike Bitcoin, Zcash transactions can be shielded to hide the sender, recipient, and value of all transactions on the blockchain. Only those with the correct view key can see the contents. Users have complete control and can opt-in to provide others with their view key at their discretion. Zcash transactions do not depend on the cooperation of other parties.

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