Project Introduction

Notional fixed-rate lending protocol, using a new on-chain automatic market maker AMM, can be used by DeFi, CeFi and institutional traders to borrow at fixed interest rates on the Ethereum network. Contributions include: concept of fCash, periodic maturity, portfolio and cash settlement.

fCash

fCash is a tokenized representation of fCash streams. It represents the number of tokens (i.e. Dai) that an account has the right to receive (CASH_RECEIVER) or is obliged to pay (CASH_PAYER) on its specified expiration date. For example, if an account holds a +100 fCash token that expires when the timestamp is 100, it has the right to obtain 100Dai at any time greater than or equal to the timestamp 100. Similarly, a -100 fCash token of the same period means that the account is obliged to pay 100Dai when the timestamp is 100. Next, we will introduce the lending mechanism in detail.

A fCash with an expiration date (i.e. expiration at timestamp 100) can be swapped with other fCash tokens with the same expiration date. However, it cannot be directly interchangeable with fCash of different periods. It should also be noted that the right to accept fCash (CASH_RECEIVER) is freely transferred, but the obligation to pay (CASH_PAYER) is not allowed.

Finally, fCash tokens are not strictly ERC20 tokens, because fCash tokens of different eligibility cannot be integrated with each other. fCash tokens can be represented under the ERC1155 token standard, which allows interoperability.