Encryption RPC api allows you to encrypt an arbitrary data bytes with some public key. Only owner of corresponding private key will be able to recover the original data stream.

Example

1. Let's generate new novacoin address first.

> getnewaddress
4NZFZZS9b8iawVA8sYtHsqNbpq57envuBz

2. Then run validateaddress to dump its public key

> validateaddress 4NZFZZS9b8iawVA8sYtHsqNbpq57envuBz
{
"isvalid" : true,
"address" : "4NZFZZS9b8iawVA8sYtHsqNbpq57envuBz",
"ismine" : true,
"watchonly" : false,
"isscript" : false,
"pubkey" : "023ca82f71f40d18f5cf6a696367a4172b87d7b3db5f45086bdb4bd4a3e3e9bde9",
"iscompressed" : true,
"account" : ""
}

3. Trying to encrypt hex representation of "Hello world!" string using this public key.

> encryptdata 023ca82f71f40d18f5cf6a696367a4172b87d7b3db5f45086bdb4bd4a3e3e9bde9 48656c6c6f20776f726c6421
02a2fe5afb10c40fc64552e1b81d8b4e991838d50c6a7129bd9f466eee29a5ab9def7cc5a3b1b526d59d06178fa4471b778e80bf8f72ae34889e58a4568f8ad2a3ecc9004a

4. Now we should be able to decrypt that cryptogram into original byte stream.

> decryptdata 4NZFZZS9b8iawVA8sYtHsqNbpq57envuBz 02a2fe5afb10c40fc64552e1b81d8b4e991838d50c6a7129bd9f466eee29a5ab9def7cc5a3b1b526d59d06178fa4471b778e80bf8f72ae34889e58a4568f8ad2a3ecc9004a
48656c6c6f20776f726c6421