From 246ce15ed2229e645d93cda574385a0c7c16e7dc Mon Sep 17 00:00:00 2001 From: Jack Grigg Date: Tue, 6 Aug 2024 20:41:03 +0000 Subject: [PATCH] ZIP 2001: Improvements to specification MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit - Add explicit consensus rules where missing. - Adjust spec to be solely modifications to other specs. - Improve definition of PoolValue_Deferred. Co-authored-by: Arya Co-authored-by: Conrado Gouvêa Co-authored-by: Daira-Emma Hopwood Co-authored-by: Kris Nuttycombe --- zips/zip-2001.rst | 118 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 104 insertions(+), 14 deletions(-) diff --git a/zips/zip-2001.rst b/zips/zip-2001.rst index 9be3855c..2d7e0c2f 100644 --- a/zips/zip-2001.rst +++ b/zips/zip-2001.rst @@ -63,15 +63,15 @@ that a funding stream may deposit funds into the deferred pool. Specification ============= -Deferred Development Fund Chain Value Pool Balance --------------------------------------------------- +Modifications to ZIP 207 [#zip-0207]_ +------------------------------------- -Full node implementations MUST track an additional -:math:`\mathsf{PoolValue}_{Deferred}` chain value pool balance, in addition to -the Sprout, Sapling, and Orchard chain value pool balances. This balance is -set to zero prior to the activation of Network Upgrade 6. +The following paragraph is added to the section **Motivation**: -ZIP 207 [#zip-0207]_ is modified as follows: + ZIP TBD [#draft-nuttycom-funding-allocation]_ directs part of the block reward + to a reserve, the distribution of which is to be determined via a future ZIP. + ZIP 2001 [#zip-2001]_ modified this ZIP to augment the funding stream mechanism + with a common mechanism to implement this proposal. In the section **Funding streams** [#zip-0207-funding-streams]_, instead of: @@ -84,15 +84,92 @@ it will be modified to read: MUST be either a transparent P2SH address, a Sapling address, or the identifier `DEFERRED_POOL`. -In the section **Consensus rules** [#zip-0207-consensus-rules]_, the following -will be added: +After the section **Funding streams**, a new section is added with the heading +"Deferred Development Fund Chain Value Pool Balance" and the following contents: - The "prescribed way" to pay to the `DEFERRED_POOL` is to add - :math:`\mathsf{FundingStream[FUND].Value}(\mathsf{height})` to - :math:`\mathsf{PoolValue}_{Deferred}`. + Full node implementations MUST track an additional + :math:`\mathsf{PoolValue}_{Deferred}` chain value pool balance, in addition to + the Sprout, Sapling, and Orchard chain value pool balances. -The protocol specification is modified to define the "total issued supply" such -that the total issued supply as of a given height is given by the function: + Define :math:`\mathsf{totalDeferredOutput}(\mathsf{height}) := \sum_{\mathsf{fs} \in \mathsf{DeferredFundingStreams}(\mathsf{height})} \mathsf{fs.Value}(\mathsf{height})` + where :math:`\mathsf{DeferredFundingStreams}(\mathsf{height})` is the set of + funding streams with a recipient of `DEFERRED_POOL` in the block at height + :math:`\mathsf{height}`. + + The :math:`\mathsf{PoolValue}_{Deferred}` chain value pool balance for a given + block chain is the sum of the values of payments to `DEFERRED_POOL` for + transactions in the block chain. + + Equivalently, :math:`\mathsf{PoolValue}_{Deferred}` for a block chain up to + and including height :math:`\mathsf{height}` is given by + :math:`\sum_{\mathsf{h} = 0}^{\mathsf{height}} \mathsf{totalDeferredOutput}(\mathsf{h})`. + + Note: :math:`\mathsf{totalDeferredOutput}(\mathsf{h})` is necessarily + zero for heights :math:`\mathsf{h}` prior to NU6 activation. + +In the section **Consensus rules** [#zip-0207-consensus-rules]_, instead of: + + - The coinbase transaction in each block MUST contain at least one output per + active funding stream that pays the stream's value in the prescribed way to + the stream's recipient address for the block's height. + +it will be modified to read: + + - In each block, for each active funding stream with a recipient other than + `DEFERRED_POOL` at that block's height, the block's coinbase transaction + MUST contain at least one output that pays the stream's value in the + prescribed way to that recipient. + +After the list of post-Canopy consensus rules, the following paragraph is added: + + The effect of the definition of :math:`\mathsf{PoolValue}_{Deferred}` above + is that payments to the `DEFERRED_POOL` cause + :math:`\mathsf{FundingStream[FUND].Value}(\mathsf{height})` to be added to + :math:`\mathsf{PoolValue}_{Deferred}` for the block chain including that block. + + +Modifications to the protocol specification +------------------------------------------- + +In section **7.1.2 Transaction Consensus Rules** [#protocol-txnconsensus]_, instead of: + + The total value in zatoshi of transparent outputs from a coinbase transaction, + minus :math:`\mathsf{v^{balanceSapling}}`, minus :math:`\mathsf{v^{balanceOrchard}}`, + MUST NOT be greater than the value in zatoshi of the block subsidy plus the transaction + fees paid by transactions in this block. + +it will be modified to read: + + For the block at height :math:`\mathsf{height}`: + + - define the "total output value" of its coinbase transaction to be the total value + in zatoshi of its transparent outputs, minus :math:`\mathsf{v^{balanceSapling}}`, + minus :math:`\mathsf{v^{balanceOrchard}}`, plus :math:`\mathsf{totalDeferredOutput}(\mathsf{height})`; + - define the "total input value" of its coinbase transaction to be the value in zatoshi + of the block subsidy, plus the transaction fees paid by transactions in the block. + + The total output value of a coinbase transaction MUST NOT be greater than its + total input value. + +where :math:`\mathsf{totalDeferredOutput}(\mathsf{height})` is defined consistently +with ZIP 207. + +Note: this ZIP and ZIP 236 both make changes to the above rule. Their combined effect +is that the last paragraph will be replaced by: + + [Pre-NU6] The total output value of a coinbase transaction MUST NOT be greater + than its total input value. + + [NU6 onward] The total output value of a coinbase transaction MUST be equal to + its total input value. + +Section **7.10 Payment of Funding Streams** [#protocol-fundingstreams]_ contains +language and definitions copied from ZIP 207; it should be updated to reflect the +changes made above. + +In section **3.4 Transactions and Treestates** [#protocol-transactions]_, a definition +of "total issued supply" will be added, such that the total issued supply as of a given +height is given by the function: .. math:: @@ -104,6 +181,12 @@ that the total issued supply as of a given height is given by the function: &+\,\; \mathsf{PoolValue}_{Deferred}(\mathsf{height}) \end{array} +The second paragraph of section **1.2 High-level Overview** [#protocol-overview]_ +should also be updated to take into account the deferred chain value pool. Since +that section of the specification is entirely non-normative, we do not give the +full wording change here. + + References ========== @@ -114,3 +197,10 @@ References .. [#zip-0207] `ZIP 207: Funding Streams `_ .. [#zip-0207-funding-streams] `ZIP 207: Funding Streams. Section: Funding streams `_ .. [#zip-0207-consensus-rules] `ZIP 207: Funding Streams. Section: Consensus rules `_ +.. [#draft-nuttycom-funding-allocation] `Draft ZIP: Block Reward Allocation for Non-Direct Development Funding `_ +.. [#zip-2001] `ZIP 2001: Lockbox Funding Streams `_ +.. [#protocol-overview] `Zcash Protocol Specification, Version 2023.4.0. Section 1.2: High-level Overview ` +.. [#protocol-transactions] `Zcash Protocol Specification, Version 2023.4.0. Section 3.4: Transactions and Treestates ` +.. [#protocol-txnconsensus] `Zcash Protocol Specification, Version 2023.4.0. Section 7.1.2: Transaction Consensus Rules ` +.. [#protocol-subsidies] `Zcash Protocol Specification, Version 2023.4.0. Section 7.8: Calculation of Block Subsidy, Funding Streams, and Founders’ Reward ` +.. [#protocol-fundingstreams] `Zcash Protocol Specification, Version 2023.4.0. Section 7.10: Payment of Funding Streams `