_section: Other Providers Others... _subsection: FallbackProvider @ @INHERIT<[[provider]]> @SRC The **FallbackProvider** is the most advanced [[provider]] available in ethers. It uses a quorum and connects to multiple [Providers](provider) as backends, each configured with a //priority// and a //weight// . When a request is made, the request is dispatched to multiple backends, randomly choosen (higher prioirty backends are always selected first) and the results from each are compared against the others. Only once the quorum has been reached will that result be accepted and returned to the caller. By default the quorum requires 50% (rounded up) of the backends to agree. The //weight// can be used to give a backend Provider more influence. _property: new ethers.providers.FallbackProvider(providers [ , quorum ]) Creates a new instance of a FallbackProvider connected to //providers//. If quorum is not specified, half of the total sum of the provider weights is used. The //providers// can be either an array of [[provider]] or [[provider-fallback-config]]. If a [[provider]] is provided, the defaults are a priority of 1 and a weight of 1. _property: provider.providerConfigs => Array<[[provider-fallback-config]]> The list of Provider Configurations that describe the backends. _property: provider.quorum => number The quorum the backend responses must agree upon before a result will be resolved. By default this is //half the sum of the weights//. _heading: FallbackProviderConfig @ _property: fallbackProviderConfig.provider => [[provider]] The provider for this configuration. _property: fallbackProviderConfig.priority => number The priority used for the provider. Higher priorities are favoured over lower priorities. If multiple providers share the same prioirty, they are choosen at random. _property: fallbackProviderConfig.stallTimeout => number The timeout (in ms) after which another [[provider]] will be attempted. This does not affect the current Provider; if it returns a result it is counted as part of the quorum. Lower values will result in more network traffic, but may reduce the response time of requests. _property: fallbackProviderConfig.weight => number The weight a response from this provider provides. This can be used if a given [[provider]] is more trusted, for example. _subsection: IpcProvider @ @INHERIT<[[provider-jsonrpc]]> @SRC The **IpcProvider** allows the JSON-RPC API to be used over a local filename on the file system, exposed by Geth, Parity and other nodes. This is only available in //node.js// (as it requires file system access, and may have additional complications due to file permissions. See any related notes on the documentation for the actual node implementation websites. _property: ipcProvider.path => string The path this [[provider]] is connected to. _subsection: UrlJsonRpcProvider @ @INHERIT<[[provider-jsonrpc]]> @SRC This class is intended to be sub-classed and not used directly. It simplifies creating a [[provider]] where a normal [[provider-jsonrpc]] would suffice, with a little extra effort needed to generate the JSON-RPC URL. _property: new ethers.providers.UrlJsonRpcProvider([ network [ , apiKey ] ]) Sub-classes do not need to override this. Instead they should override the static method ``getUrl`` and optionally ``getApiKey``. _property: urlJsonRpcProvider.apiKey => any The value of the apiKey that was returned from ``InheritedClass.getApiKey``. _property: InheritingClass.getApiKey(apiKey) => any This function should examine the //apiKey// to ensure it is valid and return a (possible modified) value to use in ``getUrl``. _property: InheritingClass.getUrl(network, apiKey) => string The URL to use for the JsonRpcProvider instance. _subsection: Web3Provider @ @INHERIT<[[provider-jsonrpc]]> The Web3Provider is meant to ease moving from a [web3.js based](link-web3) application to ethers by wraping an existing Web3-compatible (such as a [Web3HttpProvider](link-web3-http)[Web3IpcProvider](link-web3-ipc) or [Web3WsProvider](link-web3-ws)) and exposing it as an ethers.js [[provider]] which can then be used with the rest of the library. _property: new ethers.providers.Web3Provider(web3Provider [, network ]) Create a new **Web3Provider**, which wraps an [EIP-1193 Provider]() or Web3Provider-compatible Provider. _property: web3Provider.provider => Web3CompatibleProvider The provider used to create this instance.