User apparatus and manager apparatus included in blockchain network and controlling method thereof

A user apparatus connectable to a block chain system, the user apparatus comprising:

• a memory;
• a communication interface;
• and
• at least one processor configured to:
• divide a block chain consisting of a plurality of blocks into an active area and an inactive area based on a predefined standard,
• store blocks included in the active area in a first portion of the memory,
• based on a state database comprising summary information for the inactive area being received form a manager apparatus included in the block chain system, store the state database in a second portion of the memory,
• based on a transaction occurring in the block chain system, perform a validation for the transaction that occurred in the block chain system based on the state database in the second portion, and record information of the validated transaction in the blocks stored in the first portion of the memory, and
• control the communication interface to transmit to the manager apparatus, transaction information satisfying a predefined condition among a plurality of transaction information stored in the first portion of the memory.