Public blockchains allow insertion of arbitrary data. Even specific-purpose blockchains like Bitcoin already contain a lot of non-financial data. Although this data insertion can be beneficial in some use cases (e.g. proof of existence), it can also cause damage. If a blockchain contained videos with instructions on how to torture someone, there would immediately be broad consensus that this data must be deleted. But since blockchains are supposed to be immutable databases, the question is: what can be done if this happens?
Elliptic curve cryptography is becoming more and more popular. One of its main supporters is the cryptocurrency system Bitcoin which uses an elliptic curve scheme for their digital signatures. Smaller key size, a more efficient implementation than the RSA system, and a similar level of security make elliptic curve cryptography an interesting alternative to RSA. […]