> For the complete documentation index, see [llms.txt](https://docs.lumia.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lumia.org/run-a-node/network-parameters.md).

# Network parameters

**Who this is for:** operators who need block time, finality, or endpoint values while running a node. Chain ID, RPC, and endpoint values live in [`/reference/networks`](https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/reference/networks-and-endpoints).

**You should already know:** which network you're running against, mainnet or Beam testnet. Confirm from [`/reference/networks`](https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/reference/networks-and-endpoints) before configuring anything; do not copy a chain ID or RPC URL from an old tutorial.

### What to look up, and where

* **Chain ID, RPC, explorer, faucet:** [`/reference/networks`](https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/reference/networks-and-endpoints).
* **Gas and fee parameters:** [`/reference/gas-and-fees`](https://app.gitbook.com/s/chmhPiVNAafGw48c4oU2/reference/gas-and-fees).

### A note on finality, for this architecture specifically

Lumia Prism's state validity is enforced by ZK proofs, not by an optimistic challenge window. There is no dispute-period concept to configure or wait out the way there would be on an optimistic rollup. What node operators actually see is the cadence at which the network's proof-settlement process finalizes L2 to L1 withdrawals on L1. That cadence is not published as a committed SLA; do not build automation that assumes a specific settlement window without confirming it independently.

Block time is **3.02 seconds on mainnet** and **about 10 seconds on Beam testnet**.

These are observed cadences, not a protocol guarantee. Measure again before building automation that depends on a tighter figure.