Bitcoin RIPEMD160 purpose

1

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?

Jamol

Posted 2018-04-26T16:03:27.807

Reputation: 13

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 2018-04-26T22:20:58.733

Answers

2

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.

Jonas Schnelli

Posted 2018-04-26T16:03:27.807

Reputation: 5 465

Thanks Jonas Schnelli, does it also give advantage for being used together with SHA256 in terms of double hashing?Jamol 2018-04-26T21:16:50.393

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 2018-04-27T20:10:36.103