Identifying malicious nodes in a blockchain network

A method in a blockchain network, the method comprising:

• receiving, by a blockchain node from a peer blockchain node, a total amount of messages indicating blockchain transactions, the total amount of messages including at least one announcement message that contains an identifier to uniquely identify a blockchain transaction and at least one entire-transaction message that contains description data to describe the blockchain transaction;
• determining, by the blockchain node based at least in part on receiving the total amount of messages, a first amount of announcement messages received from the peer blockchain node and a second amount of entire-transaction messages received from the peer blockchain node;
• calculating, by the blockchain node, a ratio of the second amount of messages to the total amount of messages;
• comparing, by the blockchain node, the calculated ratio to a predetermined threshold ratio;
• and
• determining, by the blockchain node based at least in part on a result of the comparison, whether a peer blockchain client being utilized by the peer blockchain node to operate in the blockchain network has been modified.

A non-transitory computer-readable medium configured to store instructions, which when executed by a processor associated with a blockchain node in a blockchain network, configure the processor to:

• receive, from a peer blockchain node, a total amount of messages indicating blockchain transactions, the total amount of messages including at least one announcement message that contains an identifier to uniquely identify a blockchain transaction and at least one entire-transaction message that contains description data to describe the blockchain transaction;
• determine, based at least in part on receiving the total amount of messages, a first amount of announcement messages received from the peer blockchain node and a second amount of entire-transaction messages received from the peer blockchain node;
• calculate a ratio of the second amount of messages to the total amount of messages;
• compare the calculated ratio to a predetermined threshold ratio;
• and
• determine, based at least in part on a result of the comparison, whether a peer blockchain client being utilized by the peer blockchain node to operate in the blockchain network has been modified.