WIP

Author: daira

README.template

@@ -63,9 +63,9 @@ and the following additional ZIPs:
 - `ZIP 2006: Restricting Transfers to the Orchard Pool <zips/zip-2006.rst>`__
 - `ZIP 318: Orchard to Ironwood Migration <zips/zip-0318.rst>`__
 - `ZIP 326: NU6.3 Consequences for Wallets <zips/zip-0326.rst>`__
-
-`ZIP 209: Prohibit Negative Shielded Chain Value Pool Balances <zips/zip-0209.rst>`__
-and `ZIP 317: Proportional Transfer Fee Mechanism <zips/zip-0317.rst>`__ will be updated.
+- `ZIP 209: Prohibit Out-of-Range Chain Value Pool Balances <zips/zip-0209.rst>`__ (updated)
+- `ZIP 213: Shielded Coinbase <zips/zip-0213.rst>`__ (updated)
+- `ZIP 317: Proportional Transfer Fee Mechanism <zips/zip-0317.rst>`__ (updated).
 
 
 NU7 Candidate ZIPs

protocol/protocol.tex

@@ -1321,10 +1321,10 @@ @misc{ZIP-208
 @misc{ZIP-209,
    presort={ZIP-0209},
    author={Sean Bowe and {Daira\nbh{}Emma} Hopwood},
-   title={Prohibit Negative Shielded Value Pool Balances},
+   title={Prohibit Out-of-Range Chain Value Pool Balances},
    howpublished={Zcash Improvement Proposal 209. Created February~25, 2019.},
    url={https://zips.z.cash/zip-0209},
-   urldate={2020-11-05}
+   urldate={2020-07-06}
 }
 
 @misc{ZIP-211,

protocol/zcash.bib

@@ -1,7 +1,7 @@
 ::
 
   ZIP: 209
-  Title: Prohibit Negative Shielded Chain Value Pool Balances
+  Title: Prohibit Out-of-Range Chain Value Pool Balances
   Owners: Sean Bowe <ewillbefull@gmail.com>
           Daira-Emma Hopwood <daira@jacaranda.org>
   Status: Final
@@ -29,6 +29,10 @@ The "Orchard chain value pool balance" for a given block chain is the negation o
 ``valueBalanceOrchard`` fields for transactions in the block chain. (Before NU5 has activated,
 the Orchard chain value pool balance is zero.)
 
+The "Ironwood chain value pool balance" for a given block chain is the negation of the sum of all
+``valueBalanceIronwood`` fields for transactions in the block chain. (Before NU6.3 has activated,
+the Ironwood chain value pool balance is zero.)
+
 The terms "Testnet" and "Mainnet" are to be interpreted as described in section 3.12 of the
 Zcash Protocol Specification [#protocol-networks]_.
 
@@ -37,35 +41,33 @@ Abstract
 ========
 
 This proposal defines how the consensus rules are altered such that blocks that produce negative
-shielded chain value pool balances are prohibited.
+shielded chain value pool balances, or that cause total supply to exceed $\mathsf{MAX\_MONEY}$
+zatoshi, are prohibited.
 
 
 Motivation
 ==========
 
-It is possible for nodes to monitor the total value of notes that are shielded to, or unshielded from,
-each of the Sprout, Sapling, and Orchard value pools. If the total value that is unshielded exceeds the
-total value that was shielded for a given pool, a balance violation has occurred in the corresponding
-shielded transaction protocol.
+It is possible for nodes to monitor the total value of notes that are shielded to, or unshielded
+from, each of the *Sprout*, *Sapling*, *Orchard*, and *Ironwood chain value pools*. If the total
+value that is unshielded exceeds the total value that was shielded for a given pool, a balance
+violation has occurred in the corresponding shielded transaction protocol.
 
-It would be preferable for the network to reject blocks that result in the aforementioned balance violation.
-However, nodes do not currently react to such an event. Remediation may therefore require chain rollbacks
-and other disruption.
+It would be preferable for the network to reject blocks that result in the aforementioned balance
+violation. However, nodes do not currently react to such an event. Remediation may therefore
+require chain rollbacks and other disruption.
 
 
 Specification
 =============
 
-If any of the Sprout chain value pool balance, Sapling chain value pool balance,
-Orchard chain value pool balance, transparent chain value pool balance, or
-deferred development fund chain value pool balance would become negative in the
-block chain created as a result of accepting a block, then all nodes MUST reject
-the block as invalid.
+If the chain value pool balance for any of the *Sprout*, *Sapling*, *Orchard*, *Ironwood*,
+*transparent*, or *deferred development fund pools* would become negative in the block chain
+created as a result of accepting a block, then all nodes MUST reject the block as invalid.
 
-If the sum of these chain value pool balances (i.e. the total supply, computed
-without possibility of overflow) would become greater than $\mathsf{MAX\_MONEY}$
-zatoshis in the block chain created as a result of accepting a block, then all
-nodes MUST reject the block as invalid.
+If the sum of these chain value pool balances (i.e. the total supply, computed without possibility
+of overflow) would become greater than $\mathsf{MAX\_MONEY}$ zatoshis in the block chain created
+as a result of accepting a block, then all nodes MUST reject the block as invalid.
 
 Nodes MAY relay transactions even if one or more of them cannot be mined due to the aforementioned
 restriction.
@@ -83,8 +85,10 @@ will be produced that violate it, potentially leading to network fragmentation.
 sufficiently unlikely that the benefits of enforcing this consensus rule sooner are overwhelming.
 
 This specification was deployed in zcashd v2.0.4 for Testnet, and in zcashd v2.0.5 for Mainnet.
-The application to the Orchard chain value pool balance will be deployed from NU5 activation
-[#zip-0252]_.
+The application to the *Orchard chain value pool balance* will be deployed from NU5 activation
+[#zip-0252]_. A tightening of the rules applied by zcashd was deployed as described in [#zip-0256]_.
+The application to the *Ironwood chain value pool balance* will be deployed from NU6.3 activation
+[#zip-0258]_.
 
 
 References

zips/zip-0209.rst

@@ -147,7 +147,7 @@ References
 .. [#protocol] `Zcash Protocol Specification, Version 2021.2.16 or later <protocol/protocol.pdf>`_
 .. [#zip-0200] `ZIP 200: Network Upgrade Mechanism <zip-0200.rst>`_
 .. [#zip-0205] `ZIP 205: Deployment of the Sapling Network Upgrade <zip-0205.rst>`_
-.. [#zip-0209] `ZIP 209: Prohibit Negative Shielded Value Pool <zip-0209.rst>`_
+.. [#zip-0209] `ZIP 209: Prohibit Out-of-Range Chain Value Pool Balances <zip-0209.rst>`_
 .. [#zip-0251] `ZIP 251: Deployment of the Canopy Network Upgrade <zip-0251.rst>`_
 .. [#zip-0308] `ZIP 308: Sprout to Sapling Migration <zip-0308.rst>`_
 .. [#zerocash] `Zerocash: Decentralized Anonymous Payments from Bitcoin (extended version) <https://eprint.iacr.org/2014/349>`_

zips/zip-0211.rst

@@ -58,6 +58,8 @@ rules preventing coinbase transactions from containing shielded outputs were ext
 cover Sapling outputs. Therefore, it is now necessary to modify the consensus rules in
 order to enable miners to start using Sapling addresses. It will also be possible for
 miners to use Orchard addresses starting from activation of the NU5 upgrade [#zip-0252]_.
+After the NU6.3 upgrade, it is only possible to mine to an Orchard address by sending the
+funds to the *Ironwood pool*.
 
 
 Specification
@@ -105,11 +107,16 @@ Once the Heartwood network upgrade activates:
 
 Once the NU5 network upgrade activates:
 
-- Coinbase transactions MAY contain Sapling and/or Orchard outputs.
+- Coinbase transactions MAY contain Sapling-pool and/or Orchard-pool outputs.
 
 This does not require any change to the consensus rule given above; it is a consequence
 of other rules as of NU5 activation.
 
+Once the NU6.3 network upgrade activates:
+
+- Coinbase transactions MAY contain Sapling-pool and/or Ironwood-pool outputs.
+- Coinbase transactions MUST NOT contain any Orchard-pool component.
+
 
 Interaction with the Founders' Reward
 -------------------------------------

zips/zip-0213.rst

@@ -443,7 +443,7 @@ References
 
 .. [#BCP14] `Information on BCP 14 — "RFC 2119: Key words for use in RFCs to Indicate Requirement Levels" and "RFC 8174: Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words" <https://www.rfc-editor.org/info/bcp14>`_
 .. [#zip-0200] `ZIP 200: Network Upgrade Mechanism <zip-0200.rst>`_
-.. [#zip-0209] `ZIP 209: Prohibit Negative Shielded Chain Value Pool Balances <zip-0209.rst>`_
+.. [#zip-0209] `ZIP 209: Prohibit Out-of-Range Chain Value Pool Balances <zip-0209.rst>`_
 .. [#zip-0224] `ZIP 224: Orchard <zip-0224.rst>`_
 .. [#zip-0227] `ZIP 227: Issuance of Zcash Shielded Assets <zip-0227.rst>`_
 .. [#zip-0227-specification-global-issuance-state] `ZIP 227: Issuance of Zcash Shielded Assets — Specification: Global Issuance State <zip-0227.rst#specification-global-issuance-state>`_

zips/zip-0226.rst

@@ -685,7 +685,7 @@ References
 .. [#zip-0032-key-path-levels] `ZIP 32: Shielded Hierarchical Deterministic Wallets — Key path levels <zip-0032.rst#key-path-levels>`_
 .. [#zip-0032-orchard-key-path] `ZIP 32: Shielded Hierarchical Deterministic Wallets — Orchard key path <zip-0032.rst#orchard-key-path>`_
 .. [#zip-0200] `ZIP 200: Network Upgrade Mechanism <zip-0200.rst>`_
-.. [#zip-0209] `ZIP 209: Prohibit Negative Shielded Chain Value Pool Balances <zip-0209.rst>`_
+.. [#zip-0209] `ZIP 209: Prohibit Out-of-Range Shielded Chain Value Pool Balances <zip-0209.rst>`_
 .. [#zip-0224] `ZIP 224: Orchard <zip-0224.rst>`_
 .. [#zip-0226] `ZIP 226: Transfer and Burn of Zcash Shielded Assets <zip-0226.rst>`_
 .. [#zip-0226-note-structure-and-commitment] `ZIP 226: Transfer and Burn of Zcash Shielded Assets — Note Structure and Commitment <zip-0226.rst#note-structure-and-commitment>`_

zips/zip-0227.rst

@@ -483,7 +483,7 @@ treating the note commitment tree anchor as authorizing data rather than effecti
 
 [^zip-0203]: [ZIP 203: Transaction Expiry](zip-0203.rst)
 
-[^zip-0209]: [ZIP 209: Prohibit Negative Shielded Chain Value Pool Balances](zip-0209.rst)
+[^zip-0209]: [ZIP 209: Prohibit Out-of-Range Shielded Chain Value Pool Balances](zip-0209.rst)
 
 [^zip-0224]: [ZIP 224: Orchard Shielded Protocol](zip-0224.rst)
 

zips/zip-0229.md

@@ -59,7 +59,7 @@ The following ZIPs have been updated in varying degrees to take into account Orc
 
 - ZIP 32: Shielded Hierarchical Deterministic Wallets [#zip-0032]_
 - ZIP 203: Transaction Expiry [#zip-0203]_
-- ZIP 209: Prohibit Negative Shielded Chain Value Pool Balances [#zip-0209]_
+- ZIP 209: Prohibit Out-of-Range Chain Value Pool Balances [#zip-0209]_
 - ZIP 212: Allow Recipient to Derive Ephemeral Secret from Note Plaintext [#zip-0212]_
 - ZIP 213: Shielded Coinbase [#zip-0213]_
 - ZIP 221: FlyClient - Consensus-Layer Changes [#zip-0221]_
@@ -230,7 +230,7 @@ References
 .. [#zip-0200] `ZIP 200: Network Upgrade Mechanism <zip-0200.rst>`_
 .. [#zip-0201] `ZIP 201: Network Peer Management for Overwinter <zip-0201.rst>`_
 .. [#zip-0203] `ZIP 203: Transaction Expiry <zip-0203.rst>`_
-.. [#zip-0209] `ZIP 209: Prohibit Negative Shielded Chain Value Pool Balances <zip-0209.rst>`_
+.. [#zip-0209] `ZIP 209: Prohibit Out-of-Range Chain Value Pool Balances <zip-0209.rst>`_
 .. [#zip-0212] `ZIP 212: Allow Recipient to Derive Ephemeral Secret from Note Plaintext <zip-0212.rst>`_
 .. [#zip-0213] `ZIP 213: Shielded Coinbase <zip-0213.rst>`_
 .. [#zip-0216] `ZIP 216: Require Canonical Point Encodings <zip-0216.rst>`_