Hello everyone,
I just thought about the limitation of not being able to transfer funds from an external account to the trading account. Like it is shown in the image below.
It is interesting to me where the problem occur.
When we go through the legitimate way it would look like this:
- External Private Key signs transaction to Personal Account Public Key
- Personal Account Private Key signs transaction to the Trading Contract(account) associated with the Personal Account
External --> Personal --> Trading Contract
When we go through the illegitimate way it would look like this:
- External Private Key signs transaction to the Trading Contract(account) associated with the Personal Account
External --> Trading Contract
Problem: The Trading Contract(account) only communicates with the Personal Account, therefore this transaction will be rejected
But there could be a third way:
- Personal Account Private Key signs a transaction to the Trading Contract(account) associated with the Personal Account, where the transaction contains a transaction, already signed with the External Private Key, from the External Account to the Public Key of the Personal Account.
Personal(External-->Personal) --> Trading Contract
Hopefully I didn’t confused you too much with the last sentence 
Problem: I do not have an idea, if a blockchain or the trading contract would understand this kind of “coupled transactions”.
Why I’m asking this? I would really be happy, if there is a solution to reduce the transactions on the blockchain to a minimum before entering the trading options on the exchange.