Zcash has begun testing its NU7 upgrade on the public testnet, lowering the targeted block interval from 75 seconds to 25 seconds. The live trial gives exchanges, wallets and developers a chance to assess the changes ahead of the expected November mainnet deployment.
The upgrade activated at block 4,465,026. Zakura, which monitors the Zcash network and verifies transactions, now recognizes the new consensus rules as active on the public testnet. The separate test network used during earlier development has been shut down.
Zcash blocks contain groups of transactions, meaning a shorter target interval could reduce the time required for merchants to accept payments and exchanges to process deposits. If a service continues to require three confirmations, the targeted waiting period would drop from 225 seconds to about 75 seconds. Actual block production can vary from the target.
Because the public testnet uses coins with no monetary value, developers and infrastructure operators can test the upgrade without exposing real ZEC to the changes.
The two main Zcash node implementations have also added support for the trial. Zakura released its implementation on Oct. 1, followed by the Zcash Foundation’s test version of Zebra on Oct. 2. Network operators must use compatible software to connect to the upgraded testnet.
NU7 Redirects Transaction Fees
The upgrade introduces changes to Zcash’s fee allocation as well. Miners will receive 40% of transaction fees, while 60% will be removed from circulation and placed into a reserve intended to finance mining rewards in the future.
The faster block schedule does not mean ZEC issuance will accelerate threefold. Instead, the reward assigned to each block will be reduced to one-third, maintaining the planned overall issuance schedule.
NU7 will also disable transactions associated with Sprout, the oldest private-payment system in Zcash. Users with funds held through Sprout would need to move them before mainnet activation if they want to continue spending those funds through the existing system.
Developers are expected to assess the testnet results on Oct. 20 and decide whether to proceed with mainnet activation. Nov. 5 remains the targeted rollout date, although Zcash has not yet assigned a specific activation block for mainnet.
