Modelisation of a blockchain

Question

I would like to model a blockchain in UML. Here are the requirements that I came up with:

• User can transfer money
• Money can be transferred from a bank account to a digital wallet
• Money can be transferred from a digital wallet to a bank account
• Money can be transferred to a user (from the contact list)
• User can consult the balance of his portfolio

Here my UML class diagram:

Since I am new to the blockchain technology, I would like to know: is this diagram correct? Did I miss something?

Answer 1

I'm not a blockchain expert. However, I can give you feedback on your diagram:

• When you use verbs to label the association indicate the direction it should be read.
• Owner and Contact are Users (Specialization)
• Users are organized in a hierarchy (One to many relation between users). I'm not sure that this is your intent. I suppose that you wanted to indicate that an Owner can have several Contacts .
• It is not clear what Money is: is it a all the money a user have ? Or is it a blockchain entry (transaction) ? Make sure that the associations are in line with your definition.
• One Money instance can be transferred to several Bank Account . Not sure it's your intent.
• Is it normal that a Wallet doesn't have a User or an Owner ?

In addition, I miss the following basic elements of the technology: the block, the chain fo blocks, the (decentralised) ledger(s), and the transactions ?