Zcash NU7 Testnet Launch Speeds Up Block Times to 25 Seconds
Zcash has activated its NU7 network upgrade on the testnet, marking a significant step toward its potential mainnet implementation. The upgrade, which went live on October 4 at block 4,465,026, introduces several key changes, including a reduction in block times from 75 seconds to 25 seconds. This adjustment aims to speed up transaction confirmations, enhancing the efficiency of payments, deposits, and cross-chain transactions. Despite the faster block times, the ZEC supply will remain unchanged due to adjustments in block rewards.
NU7 also includes enhancements to shielded transactions, with restrictions designed to improve capacity and reduce the risk of spam transactions overwhelming lightweight wallets. Additionally, the upgrade introduces the Network Sustainability Mechanism (NSM), which allocates 60% of transaction fees to an account for future emission costs, while the remaining 40% goes to miners. The upgrade will also disable version 4 transactions, potentially affecting users with ZEC in Sprout shielded addresses.
The NU7 upgrade is currently being tested on the public testnet, with developers evaluating its effects on miners, wallet software, and other node software. A planned mainnet rollout is set for November 5, but this is not yet confirmed. Developers will review testnet results on October 20 to decide on the mainnet activation, including the specific block height for the upgrade.
The Zebra 7.0.0-rc.0 release, which supports NU7, was launched on October 2, encouraging node operators to test the upgrade in a live network environment. This upgrade is part of Zcash's ongoing efforts to improve its protocol, following previous upgrades like the Ironwood-related proposals.