Overview
Learn about rate limit middleware, a middleware that can be used in combination with token transfers (ICS-20) to control the amount of in and outflows of assets in a certain time period.
What is Rate Limit Middleware?
The rate limit middleware enforces rate limits on IBC token transfers coming into and out of a chain. It supports:
- Risk Mitigation: In case of a bug exploit, attack or economic failure of a connected chain, it limits the impact to the in/outflow specified for a given time period.
- Token Filtering: Through the use of a blacklist, the middleware can completely block tokens entering or leaving a domain, relevant for complicance or giving asset issuers greater control over the domains token can be sent to.
- Uninterupted Packet Flow: When desired, rate limits can be bypassed by using the whitelist, to avoid any restriction on asset in or outflows.
How it works
The rate limiting middleware determines whether tokens can flow into or out of a chain. The middleware does this by:
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Check transfer limits for an asset (Quota): When tokens are recieved or sent, the middleware determines whether the amount of tokens flowing in or out have exceeded the limit.
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Track in or outflow: When tokens enter or leave the chain, the amount transferred is tracked in state
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Block or allow token flow: Dependent on the limit, the middleware will either allow the tokens to pass through or block the tokens.
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Handle failures: If the packet timesout or fails to be delivered, the middleware ensures limits are correctly recorded.