Why Do Some Nodes Have a Minimum Fee Threshold for Relaying?

Nodes set a minimum fee threshold to protect themselves from denial-of-service (DoS) attacks and to manage the local resources (like mempool memory). If a transaction offers a fee below this threshold, the node will not accept it into its mempool or relay it to other peers.

This mechanism helps prioritize transactions that compensate the network for the cost of processing and storage.

What Are the Security Risks Associated with Operating a Large Mining Pool?
What Happens to a Transaction If It Stays in the Mempool for Too Long without Being Confirmed?
How Does a Node Decide Which Low-Fee Transactions to Drop from Its Mempool?
How Have Flash Loan Attacks Impacted the DeFi Ecosystem?
What Is the Role of a “DAG File” in Memory-Hard Mining Algorithms?
How Do Miners Prioritize Transactions with the Same Nonce but Different Gas Prices?
Does the Merkle Tree Structure Itself Consume Significant Memory?
What Is the Purpose of Setting a Minimum Fee in a Blockchain Protocol?

Glossar