cBridge Limit Parameters
Last updated
Last updated
There are certain rules limiting on source and destination chains for security purposes. When transferring assets through cBridge, it's essential to check these limit parameters beforehand.
The sending amount range is (minSend, maxSend], for Pool-based transfer, you can get the minSend/minMax on source chain Bridge contract, the address is the token address on source chain.
The screenshot is an example to get the USDC minSend Value on Ethereum.
Note if the transfer token is ETH, use the WETH token address as the query key.
The pool cap signifies the maximum volume allowed in this pool. Once the pool cap of the source chain is reached, transfers of the token from this chain are temporarily suspended until the volume decreases below the cap.
The sending amount should be matched the rule of sending amount + current volume <= pool cap
To check pool cap by handling the error in estimateAmt api when you quote the transfer.
The error code
Error Message:
You can transfer up to {remainning_amount} {token_symbol} at this moment. You may reduce your transfer amount. the remainning_amount = pool - current volume
(Aside) The pool cap limit value can be read from the inbound_lmt field in the configuration file.
If the sending amount is greater than an on-chain threshold, the transaction might be delayed for a while due to security reasons. You can retrieve these parameters from the destination chain.
delayThresholds: https://github.com/celer-network/sgn-v2-contracts/blob/4d742f6c337f06777947a73accd9f78239de92ee/contracts/safeguard/DelayedTransfer.sol#L15C40-L15C55
delayPeriod: https://github.com/celer-network/sgn-v2-contracts/blob/4d742f6c337f06777947a73accd9f78239de92ee/contracts/safeguard/DelayedTransfer.sol#L16C20-L16C31 indicates the transaction delay time in second.
The epoch volume cap restricts the amount of volume that can be transferred on the destination chain within a specific time frame.
Example code of calculating the accumulated volume
You can obtain the epochVolumeCaps , lastOpTimestamps, epochLength and corresponding token epochVolumes from the VolumeControl Contract, which has been implemented by the Bridge Contract. The accumulated volume in this period must be lower than the value specified by the "epochVolumeCaps".
