> For the complete documentation index, see [llms.txt](https://scdo-laboratory.gitbook.io/scdolab/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://scdo-laboratory.gitbook.io/scdolab/getting-started/networks.md).

# Networks and shards

## SCDO Shard0 EVM

| Field                 | Value                                                                               |
| --------------------- | ----------------------------------------------------------------------------------- |
| Network name          | `SCDO Shard0 EVM`                                                                   |
| Chain ID / network ID | `5680` (hex `0x1630`)                                                               |
| RPC URL               | `https://scdoscan.io/rpc/0`                                                         |
| Backup RPC URL        | `https://apeccapital.org/rpc/0`                                                     |
| Currency symbol       | `SCDO`                                                                              |
| Decimals              | 18                                                                                  |
| Block explorer        | `https://scdoscan.io`                                                               |
| Consensus             | Ethash proof-of-work (same as pre-merge Ethereum; 30,000-block epochs; not etchash) |
| Client                | core-geth v1.12.23 (SCDO fork)                                                      |
| Block target          | about 13 seconds                                                                    |
| Gas limit             | 30,000,000                                                                          |
| Fee model             | EIP-1559 active from block 0; base fee burned                                       |
| P2P port              | 30368                                                                               |
| ChainList             | <https://chainlist.org/chain/5680>                                                  |

### Notes for developers

* Set Solidity `evmVersion` to **`paris`**. Shanghai and later opcodes (`PUSH0`, `MCOPY`, `TLOAD`, `TSTORE`) are not enabled on Shard0 EVM.
* Send **legacy (type-0)** transactions.
* Shard0 nodes can follow company-signed checkpoints. See [Security practices](/scdolab/security-and-compliance/security.md#signed-checkpoints).

## SCDO Classic shards

SCDO Shard1 (Classic), Shard2 (Classic), Shard3 (Classic) and Shard4 (Classic) form SCDO's own original core chain.

| Item           | Value                                                                                 |
| -------------- | ------------------------------------------------------------------------------------- |
| Client         | go-scdo (source: GitHub `SCDOLAB/go-scdo`)                                            |
| Algorithm      | ZPoW                                                                                  |
| Address format | `1S01...` (Shard1), `2S02...` (Shard2), and so on                                     |
| Decimals       | 8                                                                                     |
| Wallets        | SCDO Web Wallet (<https://scdoscan.io/wallet/>) and desktop SCDO Wallet; not MetaMask |
| Accounts       | over 240,000 user accounts, searchable on the explorer                                |

The Classic chain is a fork whose genesis is at about block 2.98 million, so a fresh node starts there and syncs forward. A full node for all chains needs about 118 GB of disk.

## Classic SCDO and Shard0 EVM SCDO are separate

SCDO on the Classic shards (Shard1–4) and SCDO on Shard0 EVM are separate balances on separate chains. Classic-shard SCDO cannot be bridged or moved to Shard0 EVM, and the two are not currently interchangeable.

{% hint style="warning" %}
Always check that the sender uses the same network as your address. A `0x` address and a `1S01...` address are on different chains.
{% endhint %}