How to demonstrate that you own a blockchain address

You may have heard about blockchain, blockchain addresses and private keys. It is good to learn how they relate to each other.
In essence, a Private key is a gigantic random number, Public key is derived from the Private key. Address is simply another, more human-friendly, way to write down the Public key.

Eliptic Curve Cryptography (ECC)

ECC, an alternative technique to RSA, is a powerful cryptography approach. It generates security between key pairs for public key encryption by using the mathematics of elliptic curves.

Blockchains operate by signing transactions with ECSDA private keys. This is the essence of blockchain security, as only owner of some address can produce valid ECDSA signatures associated with this address.

In cryptography, the Elliptic Curve Digital Signature Algorithm (ECDSA) offers a variant of the Digital Signature Algorithm (DSA) which uses elliptic-curve cryptography. — wikipedia

Signing arbitrary messages

Now when you know blockchains work with ECDSA signatures, let’s learn how to sign arbitrary messages with ECDSA private key in the Peercoin web wallet.

Message signing process where a person proving the identity or ownership of the address is signing the text message with their private key and…