{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"What are the security issues and challenges of blockchain technology?","a":"Node Security: The security of nodes in a blockchain network is crucial for the overall security of the blockchain system. However, nodes are vulnerable to malicious attacks such as DDoS attacks and Sybil attacks,  which may affect the stability of the blockchain network."}]}],"pr":"f33523bf80e615b4af84bd339b52e8b283c4fb3515622551efe19744590eeb9f"}