> For the complete documentation index, see [llms.txt](https://cascadia.gitbook.io/gitbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cascadia.gitbook.io/gitbook/network/chainid-and-address-prefix.md).

# ChainID & Address Prefix

ChainID is a number that identifies a specific blockchain. This number is used to ensure that transactions are processed on the correct blockchain, and not confused with transactions on another with a similar format. ChainID also prevents replay attacks, where a transaction is broadcast on multiple blockchains to trick users into accepting the same transaction on different chains.

Address format is used to identify unique users within a blockchain network.

**Cascadia's ChainID**

Cascadia uses several Chain IDs. Choose the correct ChainID when executing Cascadia in your local environment. \
\
The ChainID for Cascadia's devnet is `cascadia_11029-1`.

**Address Prefix**

BIP-0173 introduces a new format for segregated witness output addresses. With regard to the respective network type, Cascadia has many address prefixes, including:

<table data-header-hidden><thead><tr><th width="308.3333333333333"></th><th></th></tr></thead><tbody><tr><td>Testnet</td><td><code>cascadia</code></td></tr></tbody></table>

Cascadia employs the Bech32 address format. Bech32 encoding offers reliable data integrity checks. The human-readable component offers contextual cues, helping UI designers clear error messages.