Let's try to understand why the network needs to be synchronized. We currently have a decentralized blockchain network that consists of five nodes. The data across these nodes is not consistent; data on each node might vary, which would lead to the failure of the purpose of having a blockchain. Let's try to understand this situation with the help of an example. Go to Postman and send a sample transaction, as shown in the following screenshot:
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Send this transaction to the node that's hosted on localhost:3001 by clicking on the Send button. This transaction will appear in the pendingTransactions array of localhost:3001/blockchain, which you can observe in the following screenshot:
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Now, go to any of the other nodes and check for the transactions that were sent. We won't be able to view the transactions in the...