Bitcoin uses RIPEMD160 on top of SHA256. Is its sole purpose to make public key address shorter or does it strengthen security in any way?
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2Possible duplicate of Why does Bitcoin use two hash functions (SHA-256 and RIPEMD-160) to create an address? – Raghav Sood Apr 26 '18 at 22:04
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The question you mentioned has slightly different meaning where it asks why double hashing instead of simple SHA256. My curiosity was why use RIPEMD160 with SHA256, for ex: why not SHA256d. – Jamol Apr 26 '18 at 22:20
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RIPEMD160 was designed in the open academic community and not like SHA2 by a NSA competition... one may see this as security advantage.
160bit hashes do also have less space requirements (then sha256) on the blockchain as well as in indexes, etc.
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Thanks Jonas Schnelli, does it also give advantage for being used together with SHA256 in terms of double hashing? – Jamol Apr 26 '18 at 21:16
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Most hashes in bitcoin are using double sha256. But an additional RIPEMD does protect against possible weakness in SHA256 since addresses are hashed with SHA256 and RIPEMD160. – Jonas Schnelli Apr 27 '18 at 20:10
