Zcash 将 NU7 主网升级定于 11 月 5 日

The Zcash NU7 main network upgrade is scheduled for November 5: The ecosystem team reached an agreement that the test network will be deployed on October 6.

The Zcash development team has set the target date for the NU7 main network upgrade as November 5. Previously, the engineering team within the ecosystem reached an agreement on upgrade plans including 25-second block intervals, version 4 transaction deactivations, and the Network Sustainability Mechanism. Currently, the activation plan for testnet is scheduled for October 6.

Core Summary

• Time planning: Zcash targets to activate the NU7 main network on November 5, and the test network deployment is scheduled for October 6.
• Technical changes: According to draft ZIP-218, NU7 will shorten the block generation interval from 75 seconds to 25 seconds.
• Community voting results: Token holders retained the existing halving mechanism with a support rate of 98.9% and agreed to launch a reissue of the network sustainability mechanism in February 2031 with a support rate of 96.6%.
• Security upgrade: Disable version 4 transactions upon activation to prevent legacy Sprout funds from being spent.
• Final Decision: Developers will make a final decision on whether to advance the upgrade of the main network on October 20 after carefully reviewing the performance of the NU7 test network.

Development progress and unified consensus

Sean Bowe 在9月17日的社区更新中表示，Zcash 基金会、Project Tachyon、Valar Group、ZODL、Shielded Labs 以及相关工程团队已对计划的范围和日程表达成了“一致同意”。尽管11月5日的日期已确定，但仍需经过10月20日的最终主网决策环节，该决策取决于开发人员对测试网表现的评估。

目前的开发时间表设定9月30日为功能完成的截止日期。根据 Bowe 的时间线，旨在纳入 NU7 的代码应在此日期前实现并准备好用于测试网升级。测试网随后于10月6日激活。开发人员计划观察两周的网络行为，然后于10月20日决定主网激活的高度。只有在完成这一审查后，原定的11月5日主网上线日期才会正式生效。

公告的范围并未引入新的交易格式。Bowe 指出，钱包软件预计不需要因 NU7 本身进行重大更改，但全节点、索引器和区块浏览器可能需要调整以适应新的共识规则。

ZIP-218：区块时间从75秒缩短至25秒

ZIP-218 提案建议将 Zcash 的目标区块间隔从75秒减少到25秒，这将使相同时间段内产生的区块数量增加约三倍。为了保持每日 ZEC 发行量不变，该提案通过减少每个区块支付的补贴来适应更快的出块速度。

草案指出，平均确认时间将从原来的75秒缩短至25秒。开发人员认为，这一变化对于支付、交易所存款以及当前需要等待一个或多个区块确认的跨链操作具有实用价值。

性能提升与限制：

更快的区块生成伴随着新的动作限制。ZIP-218 规定每个区块中所有池的动作总数上限为330个，其中包括最多330个 Orchard 动作、300个 Sapling 输入和输出的组合，以及25个 Sprout JoinSplits。

据草案估算，该配置将使双动作交易的 Orchard 吞吐量从每秒约2.9笔提升至6.6笔。同时，在指定的拒绝服务攻击场景下，其模型将最大屏蔽钱包同步带宽从每天271 MB降低至169 MB。

潜在风险：

更多的区块意味着额外的开销。ZIP-218 估计，钱包每天将下载约200 KB的紧凑区块头数据。由于需要在可比时间内处理三倍的区块，全节点的同步需求也会上升。

测试还考察了 stale-block（陈旧区块）风险增加的情况。草案估算，在25秒间隔下，理论上的 stale-rate 约为3.26%。在一次拥有99个地理分布的 Zebra 节点且区块大小为2 MB 的 devnet 测试中，stale-block 率达到4.86%，分叉率为0.37%。

该提案目前仍分类为“草案”，意味着在最终部署之前，技术规范仍可能发生变化。

Retain halving mechanism, postpone NSM re-issuance until 2031

The latest governance results show that the community has refused to replace Zcash's existing halving mechanism with the original issuance policy smoothing proposal.

Token holders representing 2,375,932.375 ZEC voted to retain the halving mechanism, while only 22,384.875 ZEC supported a smooth issuance curve. On this issue, the halving option received approximately 98.9% of the participation votes. Regarding when ZECs removed through the Network Sustainability Mechanism (NSM) will begin to return to circulation, 2,319,643.750 ZECs support will be in February 2031, approximately 70,240 ZECs will be in support of starting as soon as possible, and 6,283 ZECs will be in February 2027.

The Zcash Foundation, Project Tachyon, ZODL, Shielded Labs and Valar Group subsequently agreed to adopt the February 2031 timeline, describing it as the most conservative interpretation of mixed community voting results. They said the date may be revisited with another vote in the future.

Bowe's NU7 timeline therefore cites an alternative NSM implementation that allows future re-releases starting in 2031 while retaining the halving mechanism. The ordinary ZIP-234 draft still describes smoothing subsidies through an exponential decay formula, so it should not be confused with the configuration chosen after the September vote.

ZIP-235 stipulates that at least 60% of transaction fees will be removed from circulation and the remaining 40% can be used for miners. The removed ZEC is designed to be gradually returned through future block subsidies rather than permanently destroyed. The selected February 2031 timetable means that, assuming the planned rules pass the final technical review, fee derived ZECs collected through NSM may remain out of circulation for years before the reissue begins.

Version 4 trading deactivation will stop Sprout's capital spending

Nu7 is expected to disable version 4 trading when the upgrade is activated. ZIP-2003 states that the discontinuation of v4 prevents Sprout funds from being spent because the newer v5 transaction format does not support the original Sprout shield pool.

The proposal does not technically destroy or unpublish the remaining Sprout balance. Its specification retains the possibility for developers to restore the search mechanism in the future, but does not promise any such future search capabilities. The Sprout pool has been almost unused for years. Governance materials from the Zcash Foundation show that when the NU7 question was asked to voters, the pool held less than 23,000 ZECs, accounting for less than 0.1% of the total transaction volume.

In the September vote, token holders supported the immediate discontinuation of v4 on NU7. The decision follows Zcash's migration to Sapling, Orchard and the newer Ironwood architecture, which was activated with NU6.3 in early 2026.

The current production version of Zebra already supports NU6.3, and the foundation is committed to strengthening node behavior in 2026 to prepare for subsequent upgrades. Early versions of Zebra expanded the local rollback window from 99 blocks to 1,000 blocks as a defense against long-term consensus splits.

ZEC prices rose, but main-net dates remained conditional

During the governance process, ZEC prices rose significantly, although the market trend cannot be attributed solely to NU7.

CoinMarketCap data shows that on the morning of September 18, ZEC trading price was close to US$1,485, up about 9.6% in 24 hours, and trading volume exceeded US$2.6 billion. The token has received other market catalysts in September, including institutional activity and the recent U.S. launch of Zcash investment products.

According to reports, ZEC rose more than 20% on September 16 to approximately US$1,337, with market optimism and network upgrade expectations being one of the main driving factors. Back in early September, ZEC broke the $1,000 mark as Grayscale converted its Zcash Trust to a ZCSH exchange-traded product traded on NYSE Arca. According to reports, the fund's initial assets were approximately US$304 million, which grew further as ZEC prices rose.

For NU7 itself, September 30 is the next engineering checkpoint. Depending on the method preferred by token holders, features that are not ready by that deadline will be removed from the upgrade, followed by a testnet activation on October 6 and a mainnet decision on October 20.

主网激活高度尚未最终确定。开发人员计划在审查测试网升级后于10月20日设定该高度，因此11月5日作为当前预定日期，仍受此决定的约束。