Purchase Ethereum for rewarding users

Question

How can I purchase some Ethereum so that I can award it to our users for winning quiz. I am thinking of making a system where we can invoke RPC calls like this:

curl -d '{"jsonrpc":"2.0","method":"eth_sendTransaction","params": [{"from":"0xcd3b9926a4415fe1ac1090b6e2c61ff33a7be5e7", "to":"0xB708D7dF86180d1D6a486ecbc49683bb2633abE2", "value": 2e18}], "id":1}' -X POST http://localhost:8545/

The call will transfer the Ether from our totalSupply of Ether to one of our users account who wins the Quiz.

Also is it possible to create Ether accounts linked with Users using Curl request ? I want to map users in our database with the Ether account. How will we convey the Ethereum account credentials to users so that they can access it and sell Ether for real cash ?

Answer 1

You post contains too many questions to answer them at once. Moreover it seems that you miss some key concepts of Ethereum, like what accounts are and how to accessed them.

1. Account creation is just a generation of a Private Key. That might be done offline.

Creating a key is tantamount to creating an account.

• You don’t need to tell anybody else you’re doing it

• You don’t need to synchronize with the blockchain

• You don’t need to run a client

• You don’t even need to be connected to the internet

http://ethdocs.org/en/latest/account-management.html

2. I would recommend that the users will create accounts on their own and when registering to a quiz they would provide their account number. Or you may "record" their addresses capturing msg.sender inside your quiz smart contract. http://solidity.readthedocs.io/en/develop/units-and-global-variables.html?highlight=sender#block-and-transaction-properties

3. You may purchase Ethereum on crypto-currency exchange such as Kraken or Bitfinex or mine it. Maybe consider taking entrance fee from users that will participate in the quiz.