{
"daLayer": "celestia",
"name": "Blobstream",
"relayerType": {
"value": "Permissioned",
"sentiment": "warning",
"description": "Only whitelisted relayers can post attestations to this bridge."
},
"risks": {
"committeeSecurity": {
"value": "Validator set",
"sentiment": "good",
"description": "The committee requires an honest minority (less than 1/3) of members (or the network stake) to prevent the DA bridge from accepting an unavailable data commitment. \n Participation in the committee is permissionless, based only on stake requirements and an honest majority of validators processing the new operator's request to join the active set.",
"orderHint": 2
},
"upgradeability": {
"value": "No delay",
"sentiment": "bad",
"description": "There is no delay in the upgradeability of the bridge. Users have no time to exit the system before the bridge implementation update is completed."
},
"relayerFailure": {
"value": "No mechanism",
"sentiment": "bad",
"description": "The relayer role is permissioned, and the DA bridge does not have a Security Council or a governance mechanism to propose new relayers. In case of relayer failure, the DA bridge will halt and be unable to recover without the intervention of a centralized entity."
}
},
"technology": {
"description": "\n ## Architecture\n \n \n \n The Blobstream bridge is a data availability bridge that facilitates data availability commitments to be bridged between Celestia and Ethereum.\n The Blobstream bridge is composed of three main components: the **Blobstream** contract, the **Succinct Gateway** contracts, and the **Verifier** contracts. \n By default, Blobstream operates asynchronously, handling requests in a fulfillment-based manner. First, zero-knowledge proofs of Celestia block ranges are requested for proving. Requests can be submitted either off-chain through the Succinct API, or onchain through the requestCall() method of the Succinct Gateway smart contract.\n Alternatively, it is possible to run an SP1 Blobstream operator with local proving, allowing for self-generating the proofs.\n Once a proving request is received, the off-chain prover generates the proof and relays it to Blobstream contract. The Blobstream contract verifies the proof with the corresponding verifier contract and, if successful, stores the data commitment in storage. \n \n Verifying a header range includes verifying tendermint consensus (header signatures are 2/3 of stake) and verifying the data commitment root.\n By default, Blobstream is updated by the Succinct operator at a regular cadence of 1 hour. Note that the update interval can vary across chains.\n ",
"references": [
{
"title": "SP1 Blobstream Operator",
"url": "https://github.com/succinctlabs/sp1-blobstream/blob/b35c92bfcfc9a1711ea014cc871d6dd610dd5392/script/bin/operator.rs"
},
{
"title": "Succinct Gateway - Etherscan",
"url": "https://etherscan.io/address/0x6c7a05e0AE641c6559fD76ac56641778B6eCd776#code#F1#L148"
}
],
"risks": [
{
"category": "Funds can be lost if",
"text": "the DA bridge accepts an incorrect or malicious data commitment provided by 2/3 of Celestia validators."
},
{
"category": "Funds can be frozen if",
"text": "excluding L2-specific DA fallback - the permissioned relayers are unable to submit DA commitments to the Blobstream contract."
}
]
},
"usedIn": [
{
"id": "rari",
"name": "RARI Chain",
"slug": "rari"
}
],
"usedIn": [],
"validationType": {
"value": "Validity Proof",
"description": "The DA attestation requires onchain SNARK proof verification to be accepted by the bridge. Operators signatures and their corresponding stake are verified as part of the proof.",
"zkCatalogId": "sp1"
}
}
{
"badges": [
{
"id": "EVM",
"type": "VM",
"name": "EVM",
"description": "This project uses the Ethereum Virtual Machine to run its smart contracts and supports the Solidity programming language",
"action": {
"type": "scalingFilter",
"id": "vm",
"value": "EVM"
}
},
{
"id": "CelestiaBlobstream",
"id": "DAC",
"type": "DA",
"name": "Celestia with Blobstream",
"description": "This project utilizes Celestia and has Blobstream enabled, facilitating the bridging of data availability commitments between Celestia and Ethereum.",
"name": "Data Availability Committee",
"description": "There is a Data Availability Committee that provides/attests to data availability",
"action": {
"type": "publicDaHighlight",
"slug": "celestia"
"type": "selfDaHighlight"
}
},
{
"id": "Espresso",
"type": "DA",
"name": "Espresso",
"description": "This project is posting its data to Espresso",
"action": {
"type": "publicDaHighlight",
"slug": "espresso"
}
},
{
"id": "Orbit",
"type": "Stack",
"name": "Built on Arbitrum Orbit",
"description": "The project is built on Arbitrum Orbit",
"action": {
"type": "scalingFilter",
"id": "stack",
"value": "Arbitrum"
}
},
{
"id": "Arbitrum",
"type": "L3ParentChain",
"name": "Built on top of Arbitrum",
"description": "The project has Arbitrum as its host chain",
"action": {
"type": "scalingFilter",
"id": "hostChain",
"value": "Arbitrum"
}
},
{
"id": "EspressoPreconfs",
"type": "Other",
"name": "Espresso Preconfs",
"description": "The project integrates with Espresso preconfirmations. The chain batch poster publishes blocks to Espresso Network and runs in a Trusted Execution Environment (TEE) programmed to verify that only Espresso-validated batches reach the host chain.",
"action": {
"type": "scalingFilter",
"id": "other",
"value": "Espresso Preconfs"
}
},
{
"id": "Caldera",
"type": "RaaS",
"name": "Caldera",
"description": "This project was deployed via the rollup-as-a-service provider Caldera",
"action": {
"type": "scalingFilter",
"id": "raas",
"value": "Caldera"
}
}
],
"description": "RARI Chain embeds royalties on the node level to guarantee royalty payments. A secure, low-cost, decentralized Ethereum L3 blockchain powered by Arbitrum.",
"links": {
"websites": [
"https://rarichain.org/"
],
"bridges": [
"https://bridge.arbitrum.io/?destinationChain=rari-mainnet&sourceChain=arbitrum-one"
],
"documentation": [
"https://rari.docs.caldera.dev/"
],
"explorers": [
"https://mainnet.explorer.rarichain.org/"
],
"repositories": [
"https://github.com/OffchainLabs/nitro"
],
"socialMedia": [
"https://twitter.com/RariChain"
]
}
}
scalingInfo+1-1
{
"capability": "universal",
"daLayer": [
"Celestia",
"DAC",
"Espresso"
],
"hostChain": {
"id": "arbitrum",
"slug": "arbitrum",
"name": "Arbitrum One"
},
"layer": "layer3",
"proofSystem": {
"type": "Optimistic"
},
"purposes": [
"Universal",
"NFT"
],
"raas": "Caldera",
"reasonsForBeingOther": [
{
"label": "Closed proofs",
"shortDescription": "There are less than 5 external actors that can submit challenges",
"description": "Projects without a sufficiently decentralized set of challengers rely on few entities to safely update the state. A small set of challengers can collude with the proposer to finalize an invalid state, which can cause loss of funds."
}
],
"stacks": [
"Arbitrum"
],
"stage": "Not applicable",
"type": "Other",
"vm": [
"EVM"
]
}
scalingRisks+8-6
{
"host": {
"stateValidation": {
"value": "Fraud proofs (INT)",
"description": "Fraud proofs allow actors watching the chain to prove that the state is incorrect. Interactive proofs (INT) require multiple transactions over time to resolve.",
"executionDelay": 172800,
"challengeDelay": 549816,
"sentiment": "good",
"orderHint": null,
"initialBond": "3600.0",
"secondLine": "8d 8h challenge + execution delay"
},
"dataAvailability": {
"value": "Onchain",
"description": "All of the data needed for proof construction is published on Ethereum L1.",
"sentiment": "good",
"orderHint": null
},
"exitWindow": {
"value": "10d",
"description": "Non-emergency upgrades are initiated on L2 and go through a 8d delay on L2 and a 3d delay on L1. Since there is a 1d delay to force a tx (forcing the inclusion in the following state update), users have 10d to exit.",
"sentiment": "warning",
"orderHint": 864000,
"warning": {
"value": "The Security Council can upgrade with no delay.",
"sentiment": "bad"
}
},
"sequencerFailure": {
"value": "Self sequence",
"description": "In the event of a sequencer failure, users can force transactions to be included in the project's chain by sending them to L1. There can be up to a 1d delay on this operation.",
"sentiment": "good",
"orderHint": 86400,
"secondLine": "1d delay"
},
"proposerFailure": {
"value": "Self propose",
"description": "Anyone can be a Proposer and propose new roots to the L1 bridge.",
"sentiment": "good",
"orderHint": 0
}
},
"self": {
"stateValidation": {
"value": "Fraud proofs (INT)",
"description": "No actor outside of the single Proposer can submit fraud proofs. Interactive proofs (INT) require multiple transactions over time to resolve. The challenge protocol can be subject to delay attacks. There is a 6d 8h challenge period.",
"challengeDelay": 549816,
"sentiment": "bad",
"orderHint": 1,
"initialBond": "0.1",
"secondLine": "6d 8h challenge period"
},
"dataAvailability": {
"value": "External",
"description": "Proof construction and state derivation fully rely on data that is posted on Celestia. Sequencer tx roots are checked against the Blobstream bridge data roots, signed off by Celestia validators.",
"sentiment": "warning"
"value": "External (DAC)",
"description": "Proof construction relies fully on data that is NOT published onchain. There exists a Data Availability Committee (DAC) with a threshold of 1/1 that is tasked with protecting and supplying the data.",
"sentiment": "bad",
"orderHint": 1
},
"exitWindow": {
"value": "None",
"description": "There is no window for users to exit in case of an unwanted regular upgrade since contracts are instantly upgradable.",
"sentiment": "bad",
"orderHint": -86400
},
"sequencerFailure": {
"value": "Self sequence",
"description": "In the event of a sequencer failure, users can force transactions to be included in the project's chain by sending them to L1. There can be up to a 1d delay on this operation.",
"sentiment": "good",
"orderHint": 86400,
"secondLine": "1d delay"
},
"proposerFailure": {
"value": "Self propose",
"description": "Anyone can become a Proposer after 12d 17h of inactivity from the currently whitelisted Proposers.",
"sentiment": "good",
"orderHint": 1099632,
"secondLine": "12d 17h delay"
}
},
"stacked": {
"stateValidation": {
"value": "Fraud proofs (INT)",
"description": "No actor outside of the single Proposer can submit fraud proofs. Interactive proofs (INT) require multiple transactions over time to resolve. The challenge protocol can be subject to delay attacks. There is a 6d 8h challenge period.",
"challengeDelay": 549816,
"sentiment": "bad",
"orderHint": 1,
"initialBond": "0.1",
"secondLine": "6d 8h challenge period"
},
"dataAvailability": {
"value": "External",
"description": "Proof construction and state derivation fully rely on data that is posted on Celestia. Sequencer tx roots are checked against the Blobstream bridge data roots, signed off by Celestia validators.",
"sentiment": "warning"
"value": "External (DAC)",
"description": "Proof construction relies fully on data that is NOT published onchain. There exists a Data Availability Committee (DAC) with a threshold of 1/1 that is tasked with protecting and supplying the data.",
"sentiment": "bad",
"orderHint": 1
},
"exitWindow": {
"value": "None",
"description": "There is no window for users to exit in case of an unwanted regular upgrade since contracts are instantly upgradable.",
"sentiment": "bad",
"orderHint": -86400
},
"sequencerFailure": {
"value": "Self sequence",
"description": "In the event of a sequencer failure, users can force transactions to be included in the project's chain by sending them to L1. There can be up to a 2d delay on this operation.",
"sentiment": "good",
"orderHint": 172800
},
"proposerFailure": {
"value": "Self propose",
"description": "Anyone can become a Proposer after 12d 17h of inactivity from the currently whitelisted Proposers.",
"sentiment": "good",
"orderHint": 1099632
}
}
}
scalingDa+6-7
[
{
"layer": {
"value": "Celestia",
"value": "DAC",
"sentiment": "warning",
"description": "The data is posted to Celestia.",
"projectId": "celestia"
"description": "The data is posted off chain and a Data Availability Committee (DAC) is responsible for protecting and supplying it."
},
"bridge": {
"value": "Blobstream",
"sentiment": "warning",
"description": "The Blobstream DA bridge is used to attest to the data availability on Celestia.",
"projectId": "blobstream"
"value": "1/1 DAC Members",
"sentiment": "bad",
"description": "There is a threshold of 1/1 members that must sign and attest that the data is correct and available.",
"orderHint": -0.01
},
"mode": {
"value": "Transaction data",
"secondLine": "Compressed"
}
},
{
"layer": {
"value": "Espresso",
"sentiment": "warning",
"description": "The data is posted to Espresso.",
"projectId": "espresso"
},
"bridge": {
"value": "None",
"sentiment": "bad",
"description": "There is no bridge that can attest if the data has been made available.",
"orderHint": -2
},
"mode": {
"value": "Transaction data",
"secondLine": "Compressed"
}
}
]
scalingTechnology+7-8
{
"architectureImage": "orbit-optimium-blobstream-espresso",
"dataAvailability": [
{
"name": "Data is posted to Celestia",
"description": "Transactions roots are posted onchain and the full data is posted on Celestia. The blobstream bridge is used to verify attestations from the Celestia validator set that the data is indeed available.",
"name": "Data is not stored on chain",
"description": "Users transactions are not published onchain, but rather sent to external trusted parties, also known as committee members (DAC). Members of the DAC collectively produce a Data Availability Certificate (comprising BLS signatures from a quorum) guaranteeing that the data behind the new transaction batch will be available until the expiry period elapses (currently a minimum of two weeks). This signature is not verified by L1, however external Validators will skip the batch if BLS signature is not valid resulting. This will result in a fraud proof challenge if this batch is included in a consecutive state update. It is assumed that at least one honest DAC member that signed the batch will reveal tx data to the Validators if Sequencer decides to act maliciously and withhold the data. If the Sequencer cannot gather enough signatures from the DAC, it will \"fall back to rollup\" mode and by posting the full data directly to the L1 chain. The current DAC threshold is 1 out of 1.",
"risks": [
{
"category": "Funds can be lost if",
"text": "the sequencer posts an unavailable transaction root.",
"text": "the external data becomes unavailable.",
"isCritical": true
},
{
"category": "Funds can be lost if",
"text": "the data is not available on the external provider.",
"isCritical": true
"category": "Users can be censored if",
"text": "the committee restricts their access to the external data."
}
],
"references": [
{
"title": "Introducing Blobstream: streaming modular DA to Ethereum",
"url": "https://blog.celestia.org/introducing-blobstream/"
"title": "Inside AnyTrust - Arbitrum documentation",
"url": "https://developer.offchainlabs.com/inside-anytrust"
}
]
},
{
"name": "Data is posted to Espresso",
"description": "Transactions roots are posted onchain and the full data is posted on Espresso. Since the HotShot Light Client contract is not used, availability of the data is not verified against Espresso validators, meaning that the Sequencer can single-handedly publish unavailable roots.",
"risks": [
{
"category": "Funds can be lost if",
"text": "the sequencer posts an unavailable transaction root.",
"isCritical": true
},
{
"category": "Funds can be lost if",
"text": "the data is not available on the external provider.",
"isCritical": true
}
],
"references": [
{
"title": "Espresso Light Client",
"url": "https://docs.espressosys.com/network/learn/the-espresso-network/internal-functionality/light-client"
}
]
}
],
"exitMechanisms": [
{
"name": "Regular messaging",
"description": "The user initiates L2->L1 messages by submitting a regular transaction on this chain. When the block containing that transaction is settled, the message becomes available for processing on L1. The process of block finalization usually takes several days to complete.",
"risks": [],
"references": [
{
"title": "Transaction lifecycle - Arbitrum documentation",
"url": "https://developer.offchainlabs.com/tx-lifecycle"
},
{
"title": "L2 to L1 Messages - Arbitrum documentation",
"url": "https://developer.offchainlabs.com/arbos/l2-to-l1-messaging"
},
{
"title": "Mainnet for everyone - Arbitrum Blog",
"url": "https://offchain.medium.com/mainnet-for-everyone-27ce0f67c85e"
}
]
},
{
"name": "Autonomous exit",
"description": "Users can (eventually) exit the system by pushing the transaction on L1 and providing the corresponding state root. The only way to prevent such withdrawal is via an upgrade.",
"risks": [],
"references": []
}
],
"forceTransactions": {
"name": "Users can force any transaction",
"description": "Because the state of the system is based on transactions submitted on the underlying host chain and anyone can submit their transactions there it allows the users to circumvent censorship by interacting with the smart contract on the host chain directly. After a delay of 1d in which a Sequencer has failed to include a transaction that was directly posted to the smart contract, it can be forcefully included by anyone on the host chain, which finalizes its ordering.",
"risks": [],
"references": [
{
"title": "SequencerInbox.sol - source code, forceInclusion function",
"url": "https://arbiscan.io/address/0xF39c8d67B55Fef4851f9267304aA1A030E0DecAC#code"
},
{
"title": "Sequencer Isn't Doing Its Job - Arbitrum documentation",
"url": "https://docs.arbitrum.io/how-arbitrum-works/sequencer#unhappyuncommon-case-sequencer-isnt-doing-its-job"
}
]
},
"operator": {
"name": "The system has a centralized sequencer",
"description": "While forcing transaction is open to anyone the system employs a privileged sequencer that has priority for submitting transaction batches and ordering transactions.",
"risks": [
{
"category": "MEV can be extracted if",
"text": "the operator exploits their centralized position and frontruns user transactions."
}
],
"references": [
{
"title": "Sequencer - Arbitrum documentation",
"url": "https://docs.arbitrum.io/how-arbitrum-works/inside-arbitrum-nitro#the-sequencer"
}
]
},
"otherConsiderations": [
{
"name": "EVM compatible smart contracts are supported",
"description": "Arbitrum One uses Nitro technology that allows running fraud proofs by executing EVM code on top of WASM.",
"risks": [],
"references": [
{
"title": "Inside Arbitrum Nitro",
"url": "https://developer.offchainlabs.com/inside-arbitrum-nitro/"
}
]
}
],
"sequencing": {
"name": "Espresso TEE sequencer",
"description": "Integration with Espresso sequencing. \n In addition to providing regular pre-confirmations, the sequencer publishes blocks to the Espresso Network.\n The integration expects the transaction batch poster to run inside a Trusted Execution Environment (TEE), and it is programmed to verify batch inclusion in a Espresso Network block before publishing it to the host chain.\n However, the confirmations provided by Espresso Network are additive, and the batch poster can skip Espresso inclusion checks should the Espresso Network be down or unavailable.\n To ensure the batch poster is running inside a TEE, the SequencerInbox contract on the host chain was updated so that the data posting function also includes a TEE attestation as input (a \"quote\" / signature) that is verified onchain by the EspressoTEEVerifier for each batch transaction. \n The verifier checks whether the signature originates from inside the TEE and reverts if unsuccessful.",
"references": [
{
"url": "https://github.com/EspressoSystems/nitro-espresso-integration/blob/7ddcc6c036fa05cc47560552c85f30b5adedf32c/arbnode/batch_poster.go#L574",
"title": "Nitro Espresso Integration"
},
{
"url": "https://gramine.readthedocs.io/en/stable/sgx-intro.html#:~:text=The%20SGX%20quote%20is%20a%20signed%20report%20that%20contains%20the%20enclave%20measurement%20and%20the%20signer%20measurement%20of%20the%20enclave%20and%20the%20signer%20of%20the%20signer%20process%20that%20created%20the%20report.",
"title": "SGX Quote"
}
],
"risks": [
{
"category": "Withdrawals can be delayed if",
"text": "the owner of EspressoTEEVerifier updates the contract verification values (enclave hash, signer) and it is no longer possible to verify the TEE quote."
}
]
},
"stateValidation": {
"description": "Updates to the system state can be proposed and challenged by a set of whitelisted validators. If a state root passes the challenge period, it is optimistically considered correct and made actionable for withdrawals.",
"categories": [
{
"title": "State root proposals",
"description": "Whitelisted validators propose state roots as children of a previous state root. A state root can have multiple conflicting children. This structure forms a graph, and therefore, in the contracts, state roots are referred to as nodes. Each proposal requires a stake, currently set to 0.1 ETH, that can be slashed if the proposal is proven incorrect via a fraud proof. Stakes can be moved from one node to one of its children, either by calling `stakeOnExistingNode` or `stakeOnNewNode`. New nodes cannot be created faster than the minimum assertion period by the same validator, currently set to 15m. The oldest unconfirmed node can be confirmed if the challenge period has passed and there are no siblings, and rejected if the parent is not a confirmed node or if the challenge period has passed and no one is staked on it.",
"risks": [
{
"category": "Funds can be stolen if",
"text": "none of the whitelisted verifiers checks the published state. Fraud proofs assume at least one honest and able validator.",
"isCritical": true
}
],
"references": [
{
"title": "How is fraud proven - Arbitrum documentation FAQ",
"url": "https://docs.arbitrum.io/get-started/arbitrum-introduction"
}
]
},
{
"title": "Challenges",
"description": "A challenge can be started between two siblings, i.e. two different state roots that share the same parent, by calling the `startChallenge` function. Validators cannot be in more than one challenge at the same time, meaning that the protocol operates with [partial concurrency](https://medium.com/l2beat/fraud-proof-wars-b0cb4d0f452a). Since each challenge lasts 6d 8h, this implies that the protocol can be subject to [delay attacks](https://medium.com/offchainlabs/solutions-to-delay-attacks-on-rollups-434f9d05a07a), where a malicious actor can delay withdrawals as long as they are willing to pay the cost of losing their stakes. If the protocol is delayed attacked, the new stake requirement increases exponentially for each challenge period of delay. Challenges are played via a bisection game, where asserter and challenger play together to find the first instruction of disagreement. Such instruction is then executed onchain in the WASM OneStepProver contract to determine the winner, who then gets half of the stake of the loser. As said before, a state root is rejected only when no one left is staked on it. The protocol does not enforces valid bisections, meaning that actors can propose correct initial claim and then provide incorrect midpoints.",
"references": [
{
"title": "Fraud Proof Wars: Arbitrum Classic",
"url": "https://medium.com/l2beat/fraud-proof-wars-b0cb4d0f452a"
}
]
}
]
},
"stateValidationImage": "orbit",
"warning": "Fraud proof system is fully deployed but is not yet permissionless as it requires Validators to be whitelisted."
}