Need to make a smart-contract, which is signed once and executed on a regular basis.
For example, a salary contract.
Say, an employee signs the contact with the employer on the conditions that a certain amount will be transferred to him monthly. Then the contract is executed monthly and the movement of funds is made without parties involvement.
How this type of contracts is called?
There is indeed a way, but it can be a bit costly. you can Use Oraclize to set up a query in the future, and make the callback function call a specific function you would like it to and thereby also trigger the next scheduled function call. There is a tutorial/doc here.
Since there's no idea of transactions that aren't started by an external source in Ethereum, e.g. recurring payments still have to be initiated by someone each time, the way people usually do this is with a withdrawal approach. So the employee sends a call to the salary contract, basically saying "pay me", and the contract then calculates how much is owed to the employee and sends it.
