{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"What is the Tombstone concept in blockchain?","a":"The Tombstone concept in blockchain refers to the situation when a node fails or leaves the network, its data and transaction records on the blockchain are  marked as obsolete and gradually isolated in subsequent blocks. This concept is mainly used to describe the historical data processing method of failed nodes in the blockchain, ensuring the decentralization and security of the blockchain. In this process, the data of the failed node will be bundled into new blocks but marked as invalid, preventing security risks if the failed node reappears in the network. This handling method enables the blockchain network to automatically clean up failed nodes and maintain the healthy operation of the network."}]}],"pr":"39a82dd29569cef201ca7ab29defad07ebe35c7e24db86b491695d4258ce9d90"}