We are trying to build a platform where a user can buy any coin with USD/BTC. The functionality is similar to that of Polonix (Deposit/Withdrawal). So, I was not sure on how to manage users' account.
I have expertise in ethereum. So, I know how to implement such functionality with ethereum based erc-20 standard token. I have created an ethereum node where each user will have an ethereum address. Once a user buys a coin we will add(transfer) the requested coin to that ethereum address.
But I am not sure on how to manage other coins like Ripple, Synereo AMP, Litecoin etc. Do we need to have a node of all such coins which have different blockchain than ethereum?
How does polonix does this? Currently, if I want to deposit Ripple, Polonix gives me an account where I can deposit XRP, does polonix has a ripple node too? Where does these address, private and public key of these addresses reside? Another such platform is Token Market
Do these guys have nodes/wallets for every coin they support?
Is there any better way to implement such functionality?
PS: This is more a type of development idea and not exactly an issue. But I think our community is the best platform to get positive inputs.