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

# Polygon Blockchain Rails

> The settlement layer for the Open Money Stack: Polygon Chain for public settlement and Polygon CDK for dedicated, compliance-grade infrastructure.

Every component of the Open Money Stack depends on reliable settlement. The OMS offers two options depending on your requirements.

## Polygon Chain

**Public, permissionless settlement.**

Polygon Chain is the public Layer 2 network that serves as the default settlement layer for the OMS. It is open, permissionless, and production-proven at scale.

* Sub-2-second finality
* Average transaction cost of \$0.002
* \$54B in stablecoin transfer volume
* 6.4B total transactions
* 159M unique wallet addresses
* Major integrations by Revolut, Stripe, Flutterwave, and more

Polygon Chain is the right choice for applications that benefit from public auditability, open access, and the broadest possible ecosystem of tooling, liquidity, and users.

<Card title="Polygon Chain overview" icon="arrow-right" href="/pos/overview">
  Architecture, network stats, and how to start building on Polygon Chain.
</Card>

***

## Polygon CDK

**Dedicated, compliance-grade blockchain infrastructure.**

For institutions that need their own rails, Polygon Chain Development Kit (CDK) lets you launch a production-ready rollup with custom throughput, fee structures, and compliance requirements.

### Why Polygon CDK

* **20,000+ TPS** when optimized for payment workloads
* **Rollup mode** with pessimistic proof security via Agglayer, validium, or full zkRollup
* **Granular network control**: deploy as fully private or with gated access, API keys, and ACLs for read/write permissions
* **EVM-equivalent**: deploy existing smart contracts without modification; standard Ethereum tooling works without reconfiguration
* **Execution clients**: supports both op-geth and op-reth, giving operators flexibility in resource usage and performance tuning
* **Implementation providers**: Conduit and Gateway are building open source tooling and support both execution clients for production deployments
* **Migration paths**: zero-downtime migration for chains running Hyperledger Besu, preserving full data history

### Agglayer connectivity

Cross-chain interoperability and unified liquidity are native features of every Polygon CDK chain. Agglayer provides shared state, cross-chain messaging, and trustless bridging across connected networks, without additional infrastructure. This means enterprise chains are not isolated: they can interoperate with Polygon Chain and other connected L2s from day one.

### Operating modes

| Mode          | Description                                                                                     |
| ------------- | ----------------------------------------------------------------------------------------------- |
| **Sovereign** | Agglayer connectivity secured by pessimistic proofs. No prover required. Default configuration. |
| **Validium**  | ZK-secured execution with offchain data availability via a DAC.                                 |
| **zkRollup**  | Fully onchain zero-knowledge rollup for maximum security and Ethereum-aligned trust.            |

### Who Polygon CDK is for

* **Banks and financial institutions** needing dedicated settlement infrastructure with compliance controls and public auditability
* **Asset issuers** that need custom compliance rules, token economics, or throughput requirements on dedicated chain infrastructure
* **Enterprises and governments** building payment infrastructure that requires a sovereign rollup with full control over sequencing, fee policy, and data availability

<Card title="Polygon CDK docs" icon="arrow-right" href="/chain-development/cdk/index">
  Explore Polygon CDK capabilities, operating modes, and how to get started.
</Card>

***

## Choosing between them

|                      | Polygon Chain                               | Polygon CDK                                                                 |
| -------------------- | ------------------------------------------- | --------------------------------------------------------------------------- |
| **Access**           | Public, permissionless                      | Private or gated                                                            |
| **Throughput**       | 110 TPS                                     | 20,000+ TPS (payment-optimized)                                             |
| **Fee control**      | Network-determined                          | Operator-defined                                                            |
| **Compliance**       | Application-level                           | Chain-level controls, ACLs, API keys                                        |
| **Infrastructure**   | Shared public network                       | Dedicated rollup                                                            |
| **Interoperability** | Native ecosystem access                     | Via Agglayer                                                                |
| **Best for**         | Open apps, broad reach, ecosystem liquidity | Regulated institutions, high-volume payment rails, sovereign infrastructure |

Most applications start on Polygon Chain. Institutions with regulatory requirements, dedicated throughput needs, or custom fee structures deploy Polygon CDK chains that remain connected to the broader ecosystem via Agglayer.