All ndau transaction data are permanently recorded in data structures called blocks, and blocks are organized into a linear sequence over time known as the ndau blockchain. You can view this activity live by visiting the ndau blockchain explorer.
The block rate is the rate at which blocks are added to the ndau blockchain.
If one or more transactions are presented to the ndau network, a new block containing all new transactions will immediately be created and added to the blockchain.
If no new transactions have arrived within 5 minutes an “empty block” is created and added to the blockchain. This is why you will see blocks with “no transactions” on the blockchain (example).