{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"What are the types of network topologies in a blockchain?","a":"Star topology: Taking a central node as the core, other nodes are directly connected to the central node. This topology has good scalability, but the central node  becomes a bottleneck for the entire network."}]}],"pr":"b26cc7828509295dd0621ff558fe899e701f5563248cfde8ba157164dd0b2e92"}