Validating and Mining Transactions

Blockchain ledger structure

Validating Transactions

• Users must affix a digital signature using a cryptographic key to validate a transaction before submitting it.
• Once submitted, each node verifies the transaction to ensure:
  • Feasibility
  • Proper authentication
• If the transaction fails verification, it is rejected.
• If more than half of the nodes agree on the validity, the transaction is deemed legitimate and enters a queue.

Mining Transactions

• A mining node validates a set of queued transactions, grouping them into a block.
• The mining node then publishes the block across the network and adds it to the blockchain.
• Invalid transactions discovered during this process are discarded.

Impact of Transaction Modifications

• Any modification to a transaction will entirely change its hash code, affecting the block and all connected blocks.
• This creates a cascading effect across the blockchain.
• Nodes will detect the change and reject the modified transaction.