> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sundialprotocol.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Whitepaper

> Sundial Protocol: Architecture, Ledger Rules, and Implementation. What the whitepaper covers and how these docs relate to it.

**Sundial Protocol: Architecture, Ledger Rules, and Implementation** (version 1.0, 25 September 2026) is the full specification of the Sundial L2.

> **[Read the whitepaper](https://www.sundialprotocol.com/resources/whitepaper)**
>
> sundialprotocol.com/resources/whitepaper

It is licensed under CC BY-SA 4.0. The authors are Vic Genin and Sam Delaney, with specification contributors from Anastasia Labs, Fluid Tokens, P2P-Defi, IOG and the Cardano Foundation, and formal verification by IOG.

## What it covers

The whitepaper specifies the optimistic rollup. Bitcoin yield products that build on the ledger, such as Dawn and Solstice, are outside its scope and are documented under [Products](https://docs.sundialprotocol.com/products/yield-marketplace.md).

| Part | Chapters | Contents |
| - | - | - |
| I. Protocol | 1 to 7 | Ledger state, user events, the consensus contracts, the proof protocol, the 21 ledger rules and their fraud proofs, data availability, phase two validation |
| II. Implementation | 8 to 15 | The node: architecture, transaction ingress, the rule engine, block production, the data model, the SDK and the HTTP API |
| III. Operations | 16 to 20 | Deployment, service objectives, measured performance, security, verification and testing |
| Appendices | A to G | On-chain data structures, protocol parameters, reject codes, glossary, networks |

## Reading guide

* **Protocol designers and auditors:** Part I, then chapters 19 and 20. Start with chapters 3 and 5.
* **Integrators:** the introduction, then chapters 2, 8, 10 and 15, and section 19.6.
* **Node operators:** chapters 8 to 13 and Part III.

## How these docs relate to it

The [Sundial L2](https://docs.sundialprotocol.com/l2/overview.md) section of these docs summarizes the whitepaper chapter by chapter. Where the two differ, the whitepaper is authoritative.

| Docs page | Whitepaper |
| - | - |
| [Overview](https://docs.sundialprotocol.com/l2/overview.md) | Executive summary, introduction |
| [Ledger and transactions](https://docs.sundialprotocol.com/l2/ledger.md) | Chapter 1 |
| [Deposits, withdrawals and transaction orders](https://docs.sundialprotocol.com/l2/user-events.md) | Chapter 2 |
| [Consensus](https://docs.sundialprotocol.com/l2/consensus.md) | Chapter 3 |
| [Fraud proofs and ledger rules](https://docs.sundialprotocol.com/l2/fraud-proofs.md) | Chapters 4 and 5 |
| [Data availability](https://docs.sundialprotocol.com/l2/data-availability.md) | Chapter 6 |
| [Performance](https://docs.sundialprotocol.com/l2/performance.md) | Chapter 18 |
| [Security model](https://docs.sundialprotocol.com/l2/security-model.md) | Chapter 19 |
| [Protocol parameters](https://docs.sundialprotocol.com/reference/parameters.md) | Appendix C |
| [Reject codes](https://docs.sundialprotocol.com/reference/reject-codes.md) | Appendix D |

## Source material

The whitepaper's sources are public:

* Specification, formal models and code: [`sundial-protocol/sundial-monorepo`](https://github.com/sundial-protocol/sundial-monorepo)
* Supporting operational documents: [`sundial-protocol/internal-docs`](https://github.com/sundial-protocol/internal-docs)


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