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<title>RFC-0138: Election mechanism for invulnerable collators on system chains - Polkadot Fellowship RFCs</title>
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<ol class="chapter"><li class="chapter-item expanded affix "><a href="../introduction.html">Introduction</a></li><li class="spacer"></li><li class="chapter-item expanded affix "><li class="part-title">Newly Proposed</li><li class="spacer"></li><li class="chapter-item expanded affix "><li class="part-title">Proposed</li><li class="chapter-item expanded "><a href="../proposed/0150-voting-while-delegating.html">RFC-150: Allow Voting While Delegating</a></li><li class="chapter-item expanded "><a href="../proposed/0154-multi-slot-aura.html">RFC-0154: AURA Multi-Slot Collation </a></li><li class="chapter-item expanded "><a href="../proposed/0155-pUSD.html">RFC-0155: pUSD (Polkadot USD over-collateralised debt token)</a></li><li class="chapter-item expanded "><a href="../proposed/0156-bls-signatures.html">RFC-0156: Add BLS12-381 Host Functions</a></li><li class="spacer"></li><li class="chapter-item expanded affix "><li class="part-title">Approved</li><li class="chapter-item expanded "><a href="../approved/0001-agile-coretime.html">RFC-1: Agile Coretime</a></li><li class="chapter-item expanded "><a href="../approved/0005-coretime-interface.html">RFC-5: Coretime Interface</a></li><li class="chapter-item expanded "><a href="../approved/0007-system-collator-selection.html">RFC-0007: System Collator Selection</a></li><li class="chapter-item expanded "><a href="../approved/0008-parachain-bootnodes-dht.html">RFC-0008: Store parachain bootnodes in relay chain DHT</a></li><li class="chapter-item expanded "><a href="../approved/0009-improved-net-light-client-requests.html">RFC-0009: Improved light client requests networking protocol</a></li><li class="chapter-item expanded "><a href="../approved/0010-burn-coretime-revenue.html">RFC-0010: Burn Coretime Revenue</a></li><li class="chapter-item expanded "><a href="../approved/0012-process-for-adding-new-collectives.html">RFC-0012: Process for Adding New System Collectives</a></li><li class="chapter-item expanded "><a href="../approved/0013-prepare-blockbuilder-and-core-runtime-apis-for-mbms.html">RFC-0013: Prepare Core runtime API for MBMs</a></li><li class="chapter-item expanded "><a href="../approved/0014-improve-locking-mechanism-for-parachains.html">RFC-0014: Improve locking mechanism for parachains</a></li><li class="chapter-item expanded "><a href="../approved/0017-coretime-market-redesign.html">RFC-0017: Coretime Market Redesign</a></li><li class="chapter-item expanded "><a href="../approved/0022-adopt-encointer-runtime.html">RFC-0022: Adopt Encointer Runtime</a></li><li class="chapter-item expanded "><a href="../approved/0026-sassafras-consensus.html">RFC-0026: Sassafras Consensus Protocol</a></li><li class="chapter-item expanded "><a href="../approved/0032-minimal-relay.html">RFC-0032: Minimal Relay</a></li><li class="chapter-item expanded "><a href="../approved/0042-extrinsics-state-version.html">RFC-0042: Add System version that replaces StateVersion on RuntimeVersion</a></li><li class="chapter-item expanded "><a href="../approved/0043-storage-proof-size-hostfunction.html">RFC-0043: Introduce storage_proof_size Host Function for Improved Parachain Block Utilization</a></li><li class="chapter-item expanded "><a href="../approved/0045-nft-deposits-asset-hub.html">RFC-0045: Lowering NFT Deposits on Asset Hub</a></li><li class="chapter-item expanded "><a href="../approved/0047-assignment-of-availability-chunks.html">RFC-0047: Assignment of availability chunks to validators</a></li><li class="chapter-item expanded "><a href="../approved/0048-session-keys-runtime-api.html">RFC-0048: Generate ownership proof for SessionKeys</a></li><li class="chapter-item expanded "><a href="../approved/0050-fellowship-salaries.html">RFC-0050: Fellowship Salaries</a></li><li class="chapter-item expanded "><a href="../approved/0056-one-transaction-per-notification.html">RFC-0056: Enforce only one transaction per notification</a></li><li class="chapter-item expanded "><a href="../approved/0059-nodes-capabilities-discovery.html">RFC-0059: Add a discovery mechanism for nodes based on their capabilities</a></li><li class="chapter-item expanded "><a href="../approved/0078-merkleized-metadata.html">RFC-0078: Merkleized Metadata</a></li><li class="chapter-item expanded "><a href="../approved/0084-general-transaction-extrinsic-format.html">RFC-0084: General transactions in extrinsic format</a></li><li class="chapter-item expanded "><a href="../approved/0091-dht-record-creation-time.html">RFC-0091: DHT Authority discovery record creation time</a></li><li class="chapter-item expanded "><a href="../approved/0097-unbonding_queue.html">RFC-0097: Unbonding Queue</a></li><li class="chapter-item expanded "><a href="../approved/0099-transaction-extension-version.html">RFC-0099: Introduce a transaction extension version</a></li><li class="chapter-item expanded "><a href="../approved/0100-xcm-multi-type-asset-transfer.html">RFC-0100: New XCM instruction: InitiateAssetsTransfer</a></li><li class="chapter-item expanded "><a href="../approved/0101-xcm-transact-remove-max-weight-param.html">RFC-0101: XCM Transact remove require_weight_at_most parameter</a></li><li class="chapter-item expanded "><a href="../approved/0103-introduce-core-index-commitment.html">RFC-0103: Introduce a CoreIndex commitment and a SessionIndex field in candidate receipts</a></li><li class="chapter-item expanded "><a href="../approved/0105-xcm-improved-fee-mechanism.html">RFC-0105: XCM improved fee mechanism</a></li><li class="chapter-item expanded "><a href="../approved/0107-xcm-execution-hints.html">RFC-0107: XCM Execution hints</a></li><li class="chapter-item expanded "><a href="../approved/0108-xcm-remove-testnet-ids.html">RFC-0108: Remove XCM testnet NetworkIds</a></li><li class="chapter-item expanded "><a href="../approved/0122-alias-origin-on-asset-transfers.html">RFC-0122: Asset transfers can alias XCM origin on destination to original origin</a></li><li class="chapter-item expanded "><a href="../approved/0123-pending-code-as-storage-location-for-runtime-upgrades.html">RFC-0123: Introduce :pending_code as intermediate storage key for the runtime code</a></li><li class="chapter-item expanded "><a href="../approved/0125-xcm-asset-metadata.html">RFC-0125: XCM Asset Metadata</a></li><li class="chapter-item expanded "><a href="../approved/0126-introduce-pvq.html">RFC-0126: Introduce PVQ (PolkaVM Query)</a></li><li class="chapter-item expanded "><a href="../approved/0135-compressed-blob-prefixes.html">RFC-0135: Compressed Blob Prefixes</a></li><li class="chapter-item expanded "><a href="../approved/0139-faster-erasure-coding.html">RFC-0139: Faster Erasure Coding</a></li><li class="chapter-item expanded "><a href="../approved/0146-deflationary-fee-proposal.html">RFC-0146: Deflationary Transaction Fee Model for the Relay Chain and its System Parachains</a></li><li class="chapter-item expanded "><a href="../approved/0149-rfc-1-renewal-adjustment.html">RFC-0149: Renewal Adjustment</a></li><li class="spacer"></li><li class="chapter-item expanded affix "><li class="part-title">Stale</li><li class="chapter-item expanded "><a href="../stale/0000-pre-elves_soft.html">RFC-0000: Pre-ELVES soft concensus</a></li><li class="chapter-item expanded "><a href="../stale/0000-rewards.html">RFC-0000: Validator Rewards</a></li><li class="chapter-item expanded "><a href="../stale/0004-remove-unnecessary-allocator-usage.html">RFC-0004: Remove the host-side runtime memory allocator</a></li><li class="chapter-item expanded "><a href="../stale/0006-dynamic-pricing-for-bulk-coretime-sales.html">RFC-0006: Dynamic Pricing for Bulk Coretime Sales</a></li><li class="chapter-item expanded "><a href="../stale/0034-xcm-absolute-location-account-derivation.html">RFC-34: XCM Absolute Location Account Derivation</a></li><li class="chapter-item expanded "><a href="../stale/0035-conviction-voting-delegation-modifications.html"> RFC-0035: Conviction Voting Delegation Modifications</a></li><li class="chapter-item expanded "><a href="../stale/0044-rent-based-registration.html">RFC-0044: Rent based registration model</a></li><li class="chapter-item expanded "><a href="../stale/0054-remove-heap-pages.html">RFC-0054: Remove the concept of "heap pages" from the client</a></li><li class="chapter-item expanded "><a href="../stale/0070-x-track-kusamanetwork.html">RFC-0070: X Track for @kusamanetwork</a></li><li class="chapter-item expanded "><a href="../stale/0073-referedum-deposit-track.html">RFC-0073: Decision Deposit Referendum Track</a></li><li class="chapter-item expanded "><a href="../stale/0074-stateful-multisig-pallet.html">RFC-0074: Stateful Multisig Pallet</a></li><li class="chapter-item expanded "><a href="../stale/0077-increase-max-length-of-identity-pgp-fingerprint-value.html">RFC-0077: Increase maximum length of identity PGP fingerprint values from 20 bytes</a></li><li class="chapter-item expanded "><a href="../stale/0088-broker-pallet-slashable-deposit-purchaser-reputation-reserved-cores.html">RFC-0088: Add slashable locked deposit, purchaser reputation, and reserved cores for on-chain identities to broker pallet</a></li><li class="chapter-item expanded "><a href="../stale/00xx-secondary-marketplace-for-regions.html">RFC-0001: Secondary Market for Regions</a></li><li class="chapter-item expanded "><a href="../stale/00xx-smart-contracts-coretime-chain.html">RFC-0002: Smart Contracts on the Coretime Chain</a></li><li class="chapter-item expanded "><a href="../stale/0102-offchain-parachain-runtime-upgrades.html">RFC-0000: Feature Name Here</a></li><li class="chapter-item expanded "><a href="../stale/0106-xcm-remove-fees-mode.html">RFC-0106: Remove XCM fees mode</a></li><li class="chapter-item expanded "><a href="../stale/0111-pure-proxy-replication.html">RFC-0111: Pure Proxy Replication</a></li><li class="chapter-item expanded "><a href="../stale/0112-compress-state-response-message-in-state-sync.html">RFC-0112: Compress the State Response Message in State Sync</a></li><li class="chapter-item expanded "><a href="../stale/0114-secp256r1-hostfunction.html">RFC-0114: Introduce secp256r1_ecdsa_verify_prehashed Host Function to verify NIST-P256 elliptic curve signatures</a></li><li class="chapter-item expanded "><a href="../stale/0117-unbrick-collective.html">RFC-0117: The Unbrick Collective</a></li><li class="chapter-item expanded "><a href="../stale/0120-referenda-confirmation-by-candle-mechanism.html">RFC-0120: Referenda Confirmation by Candle Mechanism</a></li><li class="chapter-item expanded "><a href="../stale/0124-extrinsic-version-5.html">RFC-0124: Extrinsic version 5</a></li><li class="chapter-item expanded "><a href="../stale/0138-invulnerable-collator-election.html" class="active">RFC-0138: Election mechanism for invulnerable collators on system chains</a></li><li class="chapter-item expanded "><a href="../stale/0152-decentralized-convex-preference-coretime-market-for-polkadot.html">RFC-0152: Decentralized Convex-Preference Coretime Market for Polkadot</a></li><li class="chapter-item expanded "><a href="../stale/RFC-114 Adjust Tipper Track Confirmation Periods.html">RFC-114: Adjust Tipper Track Confirmation Periods</a></li><li class="chapter-item expanded "><a href="../stale/TODO-stale-nomination-reward-curve.html">RFC-TODO: Stale Nomination Reward Curve</a></li><li class="chapter-item expanded "><a href="../stale/xxxx-improve-the-security-of-proof-of-possession.html">RFC-XXXX: Adding customized mandatory context to proof of possession statement</a></li></ol>
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<h1 class="menu-title">Polkadot Fellowship RFCs</h1>
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<p><a href="https://github.com/polkadot-fellows/RFCs/pull/138">(source)</a></p>
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<p><strong>Table of Contents</strong></p>
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<ul>
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<li><a href="#rfc-0138-election-mechanism-for-invulnerable-collators-on-system-chains">RFC-0138: Election mechanism for invulnerable collators on system chains</a>
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<ul>
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<li><a href="#summary">Summary</a></li>
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<li><a href="#motivation">Motivation</a></li>
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<li><a href="#stakeholders">Stakeholders</a></li>
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<li><a href="#explanation">Explanation</a>
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<ul>
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<li><a href="#proposal">Proposal</a></li>
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<li><a href="#how-it-works">How it works</a></li>
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<li><a href="#motivations-behind-the-particularities-of-this-mechanism">Motivations behind the particularities of this mechanism</a></li>
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<li><a href="#corner-cases">Corner cases</a></li>
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</ul>
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</li>
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<li><a href="#drawbacks">Drawbacks</a></li>
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<li><a href="#testing-security-and-privacy">Testing, Security, and Privacy</a></li>
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<li><a href="#performance-ergonomics-and-compatibility">Performance, Ergonomics, and Compatibility</a>
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<ul>
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<li><a href="#performance">Performance</a></li>
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<li><a href="#ergonomics">Ergonomics</a></li>
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<li><a href="#compatibility">Compatibility</a></li>
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</ul>
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</li>
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<li><a href="#prior-art-and-references">Prior Art and References</a></li>
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<li><a href="#unresolved-questions">Unresolved Questions</a></li>
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<li><a href="#future-directions-and-related-material">Future Directions and Related Material</a></li>
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</ul>
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</li>
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</ul>
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<h1 id="rfc-0138-election-mechanism-for-invulnerable-collators-on-system-chains"><a class="header" href="#rfc-0138-election-mechanism-for-invulnerable-collators-on-system-chains">RFC-0138: Election mechanism for invulnerable collators on system chains</a></h1>
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<div class="table-wrapper"><table><thead><tr><th></th><th></th></tr></thead><tbody>
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<tr><td><strong>Start Date</strong></td><td>28 January 2025</td></tr>
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<tr><td><strong>Description</strong></td><td>Mechanism for electing invulnerable collators on system chains.</td></tr>
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<tr><td><strong>Authors</strong></td><td>George Pisaltu</td></tr>
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</tbody></table>
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</div>
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<h2 id="summary"><a class="header" href="#summary">Summary</a></h2>
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<p>The current election mechanism for permissionless collators on system chains was introduced in
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<a href="https://github.com/polkadot-fellows/RFCs/blob/main/text/0007-system-collator-selection.md">RFC-7</a>.
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This RFC proposes a mechanism to facilitate replacements in the invulnerable sets of system chains
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by breaking down barriers that exist today.</p>
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<h2 id="motivation"><a class="header" href="#motivation">Motivation</a></h2>
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<p>Following RFC-7 and the <a href="https://github.com/paritytech/polkadot-sdk/pull/1340">introduction of the collator election
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mechanism</a>, anyone can now collate on a system
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chain on the permissionless slots, but the invulnerable set has been a contentious issue among
|
|
current collators on system chains as the path towards an invulnerable slot is almost impossible to
|
|
pursue. From a technical standpoint, nothing is preventing a permissionless collator, or anyone for
|
|
that matter, from submitting a referendum to remove one collator from the invulnerable set and add
|
|
themselves in their place. However, as it quickly becomes obvious, such a referendum would be very
|
|
difficult to pass under normal circumstances.</p>
|
|
<p>The first reason this would be contentious is that there is no significant difference between
|
|
collators with good performance. There is no reasonable way to keep track of arbitrary data on-chain
|
|
which could clearly and consistently distinguish between one collator or another. Collators that
|
|
perform well propose blocks when they are supposed to and that is what is being tracked on-chain.
|
|
Any other metrics for performance are arbitrary as far as the runtime logic is concerned and should
|
|
be reasoned upon by humans using public discussion and a referendum.</p>
|
|
<p>The second reason for this is the inherently social aspect of this action. Even just proposing the
|
|
referendum would be perceived as an attack on a specific collator in the set, singling them out,
|
|
when in reality the proposer likely just wants to be part of the set and doesn't necessarily care
|
|
who is kicked. In order to consolidate their position, the other invulnerables will rally behind the
|
|
one that was challenged and the bid to replace one invulnerable will probably fail.</p>
|
|
<p>Existing invulnerables have a vested interest in protecting any other invulnerable from such attacks
|
|
so that they themselves would be protected if need be. The existing collator set has already
|
|
demonstrated that they can work together and subvert the free market mechanism offered by the
|
|
runtime when they agreed to not outbid each other on permissionless slots after the new collator
|
|
selection mechanism was introduced.</p>
|
|
<p>The existing invulnerable set on a given system chain are there for a reason; they have demonstrated
|
|
reliability in the past and were rewarded by governance with invulnerable slots and a bounty to
|
|
cover their expenses. This means they have a solid reputation and a strong say in governance over
|
|
matters related to collation. The optics of a permissionless collator actively challenging an
|
|
invulnerable, even when it's justified, combined with the support of other invulnerables, make the
|
|
invulnerable set de facto immutable.</p>
|
|
<p>While there should be strong guarantees of stability for invulnerables, they should not be a closed
|
|
circle. The aim of this RFC is to provide a clear, reasonable, fair, and socially acceptable path
|
|
for a permissionless collator with a proven track record to become an invulnerable while preserving
|
|
the stability of the invulnerable set of a system parachain.</p>
|
|
<h2 id="stakeholders"><a class="header" href="#stakeholders">Stakeholders</a></h2>
|
|
<ul>
|
|
<li>Infrastructure providers (people who run validator/collator nodes)</li>
|
|
<li>Polkadot Treasury</li>
|
|
</ul>
|
|
<h2 id="explanation"><a class="header" href="#explanation">Explanation</a></h2>
|
|
<h3 id="proposal"><a class="header" href="#proposal">Proposal</a></h3>
|
|
<p>This RFC proposes a periodic, mandatory, round-robin, two-round election mechanism for
|
|
invulnerables.</p>
|
|
<h3 id="how-it-works"><a class="header" href="#how-it-works">How it works</a></h3>
|
|
<p>The election should be implemented on top of the current logic in the <code>collator-selection</code> pallet.
|
|
In this mechanism, candidates would register for the first round of the next election by placing
|
|
deposits.</p>
|
|
<p>When the period between elections passes, the first round of the election starts with every
|
|
candidate that registered, excluding the incumbent, as an option on the ballot. Votes should be
|
|
expressed using tokens which should not be available for other transactions while the election is
|
|
ongoing in order to introduce some opportunity cost to voting. After a certain amount of time
|
|
passes, the election closes and the candidate who wins the first round of the election advances to
|
|
the second and final round of the election. The deposits held for voting in the first round must be
|
|
released before the second round.</p>
|
|
<p>In the second round of the election, the winner of the first round has the chance to replace the
|
|
invulnerable currently holding the slot. A referendum is submitted to replace the incumbent with the
|
|
winner of the first round of the election, turning the second round of the election into a
|
|
<code>conviction-voting</code> compatible referendum. If the referendum fails, the incumbent keeps their slot.</p>
|
|
<p>The period between elections should be configurable at the <code>collator-selection</code> pallet level. A full
|
|
election cycle ends when the pallet held an election for every single invulnerable slot. To qualify
|
|
for the ballot, candidates must have been collating for at least one period from a permissionless
|
|
slot or be the incumbent.</p>
|
|
<h3 id="motivations-behind-the-particularities-of-this-mechanism"><a class="header" href="#motivations-behind-the-particularities-of-this-mechanism">Motivations behind the particularities of this mechanism</a></h3>
|
|
<ul>
|
|
<li>Round-robin - It is not desirable to allow any election of the entire invulnerable set at once
|
|
because the main purpose of invulnerables is to ensure the stability, reliability and liveness of
|
|
the parachain. It is safer to change them one by one and, in case mistakes happen, governance has
|
|
time to react without endangering the liveness of any chain.</li>
|
|
<li>Two-round voting - it's useful to separate the election process into two distinct steps: the
|
|
first, less important step of determining the challenger at the pallet level through deposits; the
|
|
second, more important step of actually trying to replace the invulnerable by referendum, which is
|
|
the same mechanism the invulnerable used to acquire the slot in the first place. It is not so
|
|
important who is trying to replace the incumbent as long as they meet the requirements and they
|
|
have a clear way to get to the second round of the election. </li>
|
|
<li>Mandatory - The runtime, not any particular individual, is actively pushing the invulnerables to
|
|
convince people that they not only deserve to keep their invulnerable slots, but that they deserve
|
|
it more than any of the other candidates that registered; the rules of the chain enforce this
|
|
mechanism so no blame or ill-intent can be attributed to other individuals.</li>
|
|
<li>Periodic - In order to provide a reasonable path towards an invulnerable slot, no seat can be
|
|
permanent and should be challenged periodically.</li>
|
|
<li>Ballot qualification - Any invulnerable collator must have a proven track record as a collator, so
|
|
allowing only current permissionless collators to run against the current invulnerable minimizes
|
|
the chance of human error by restricting the number of incompatible choices.</li>
|
|
</ul>
|
|
<h3 id="corner-cases"><a class="header" href="#corner-cases">Corner cases</a></h3>
|
|
<ul>
|
|
<li>If no candidate registers for an election, the slot will become empty, unless the number of
|
|
collators is lower than the minimum number allowed by the pallet configuration, defined in
|
|
<code>MinEligibleCollators</code>.</li>
|
|
<li>In case of equality for the first and second positions, the candidate that registered first wins the election.</li>
|
|
<li>In case no collator registers or qualifies for the first round of the election, the incumbent is
|
|
automatically granted the win and gets to keep the invulnerable slot.</li>
|
|
</ul>
|
|
<h2 id="drawbacks"><a class="header" href="#drawbacks">Drawbacks</a></h2>
|
|
<p>The first major drawback of this proposal is that it would put more responsibility on governance by
|
|
having people vote regularly in order to maintain the invulnerable collator set on each chain. Today
|
|
the <code>collator-selection</code> pallet employs a fire-and-forget system where the invulnerables are chosen
|
|
once by governance vote. Although in theory governance can always intervene to elect new
|
|
invulnerables, for the reasons stated in this RFC this is not the case in practice. Moving away from
|
|
this system means more action is needed from governance to ensure the stability of the invulnerable
|
|
collator sets on each system chain, which automatically increases the probability of errors.
|
|
However, governance is the ultimate source of truth on-chain and there is a lot more at stake in the
|
|
hands of governance than the invulnerable collator sets on system chains, so I think this risk is
|
|
acceptable.</p>
|
|
<p>The second drawback of this proposal is the imperfect voting mechanism. Probably the simplest and
|
|
most fair voting system for this scenario would have been First Past the Post, where all candidates
|
|
participate in a single election round and the candidate with the most votes wins the election
|
|
outright. However, the downside of such a system is the technical complexity behind running such an
|
|
election on-chain. This election mechanism would require a multiple choice referendum implementation
|
|
in the <code>collator-selection</code> pallet or at the system level somewhere else (e.g. on the Collectives
|
|
chain), which would be a mix between the <code>conviction-voting</code> and <code>staking</code> pallets and would
|
|
possibly communicate with all system chains via XCM. While this voting system could be useful in
|
|
other contexts as well, I don't think it's worth conditioning the invulnerable collator redesign on
|
|
a separate implementation of the multiple choice voting system when the Two-Round proposed achieves
|
|
the objectives of this RFC.</p>
|
|
<h2 id="testing-security-and-privacy"><a class="header" href="#testing-security-and-privacy">Testing, Security, and Privacy</a></h2>
|
|
<p>All election mechanisms as well as corner cases can be covered with unit tests.</p>
|
|
<h2 id="performance-ergonomics-and-compatibility"><a class="header" href="#performance-ergonomics-and-compatibility">Performance, Ergonomics, and Compatibility</a></h2>
|
|
<h3 id="performance"><a class="header" href="#performance">Performance</a></h3>
|
|
<p>The chain will have to run extrinsics to start and end elections periodically, but the impact in
|
|
terms of weight and PoV size is negligible.</p>
|
|
<h3 id="ergonomics"><a class="header" href="#ergonomics">Ergonomics</a></h3>
|
|
<p>The invulnerables will be the most affected group, as they will have to now compete in elections
|
|
periodically to secure their spots. Permissionless candidates will now have a clear, though not
|
|
guaranteed, path towards becoming an invulnerable, at least for a period of time.</p>
|
|
<h3 id="compatibility"><a class="header" href="#compatibility">Compatibility</a></h3>
|
|
<p>Any changes to the election mechanism of invulnerables should be compatible with the current
|
|
invulnerable set interaction with the collator set chosen at the session boundary. The current
|
|
invulnerable set for each chain can be grandfathered in when upgrading the <code>collator-selection</code>
|
|
pallet version.</p>
|
|
<h2 id="prior-art-and-references"><a class="header" href="#prior-art-and-references">Prior Art and References</a></h2>
|
|
<p>This RFC builds on RFC-7, which introduced the election mechanism for system chain collators.</p>
|
|
<h2 id="unresolved-questions"><a class="header" href="#unresolved-questions">Unresolved Questions</a></h2>
|
|
<ul>
|
|
<li>How long should the period between individual elections be? How long should the full election
|
|
cycle be?
|
|
<ul>
|
|
<li>There should be a bit more than one month between individual elections, so that if there are 5
|
|
invulnerables on system chains, a full election cycle would take 6 months.</li>
|
|
</ul>
|
|
</li>
|
|
<li>How long should the voting stay open?
|
|
<ul>
|
|
<li>It probably should just be a fixed period (e.g. 1 week) or maybe it can be the entire period
|
|
before the next election begins.</li>
|
|
</ul>
|
|
</li>
|
|
</ul>
|
|
<h2 id="future-directions-and-related-material"><a class="header" href="#future-directions-and-related-material">Future Directions and Related Material</a></h2>
|
|
<p>The main spinoff of this RFC might be a multiple choice poll implementation in a separate pallet to
|
|
hold a First Past the Post election instead of the Two-Round System proposed, which would prompt a
|
|
migration to the new voting system within the <code>collator-selection</code> pallet. Additionally, a more
|
|
complex solution where the voting for all system chains happens in a single place which then sends
|
|
XCM responses with election results back to system chains can be implemented in the next iteration
|
|
of this RFC.</p>
|
|
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