Users can upload their kyc documents to filecoin network through DE-KYC. Storage deal and Data access control will be done on server side of DE-KYC.
3rd party services like Twilio can be used to verify phone number and email. For verifying passport etc which require manual verification, combination of image processing and manual verification is used.
Zero knowledge proof is used for verification while maintaining privacy.
Used web3js package for offchain verification of KYC documents as it is easier to implement complex strategies as compared to onchain solidity code.
Since, Filecoin gives unique hash for each kyc file, multiple parties can verify the same document withou needing to upload again and again.