The Lava Loans protocol (v2) is a scheme designed by Lava constructing upon Discreet Log Contracts (DLCs) to facilitate a trustless Bitcoin collateralized mortgage system. The large implosion out there final cycle attributable to centralized platforms facilitating Bitcoin backed loans confirmed that left unchecked, such services can current a large systemic danger to the whole market within the ecosystem.
Lava seeks to supply the identical utility customers of such centralized platforms sought in a decentralized and atomic trend, utilizing DLCs.
DLCs, for these unfamiliar with the idea, are a wise contract designed to settle a sure approach relying on the end result of some occasion outdoors of the Bitcoin protocol, i.e. the value of Bitcoin, the end result of a sports activities sport, and so forth. That is completed by relying on an oracle, or a set of a number of oracles, who signal a message testifying to the precise consequence of the actual world occasion. These signed messages are used as the idea for adapter signatures that unlock particular pre-signed transactions that settle the contract a sure approach.
The good thing about DLCs is they are often completed privately. So long as the oracle(s) publish the keys they are going to use to signal outcomes for particular occasions at particular occasions, any consumer can take that data and assemble pre-signed transactions to settle accurately based mostly on the vary of potential outcomes with out the oracle ever understanding {that a} contract exists. The oracle merely publicly broadcasts the signed message on the acceptable time, and that provides each customers all of the wanted data to settle the contract accurately.
Lava is designed to utilize a modified variant of DLCs, along with stablecoins on different networks, so as to facilitate a bitcoin collateralized mortgage that may be entered into atomically and trustlessly (i.e. guaranteeing that the lender can not acquire management of bitcoin with out releasing management of the stablecoin to the borrower).
Instantiation
The funding of the DLC is a two step course of within the Lava protocol, given the requirement that the stablecoins given in alternate for the collateral being locked within the contract should be atomic. Within the first part, the borrower creates a script that permits them to assert their coin again after a timelock, or permits the lender to finish the funding with a hash preimage and signature from the borrower. They then signal a transaction that strikes the cash from this staging handle into the DLC. The lender then exchanges a hashlock to be used later within the protocol with the borrower.
From this level, the lender must fund an analogous atomic alternate contract with the borrower on the chain internet hosting the stablecoin. This contract permits the borrower to assert the stablecoins with the identical preimage used to finalize the DLC on Bitcoin, or the lender to reclaim the stablecoins after a timeout. The contract on the alt-chain can be collateralized with additional stablecoins that stay within the contract, and can’t be claimed again by the lender till after the completion of the contract. This can be defined later.
After the setup part, the borrower releases the preimage to the hashlock, claims the stablecoins, and permits the lender to maneuver the bitcoin from the staging handle right into a finalized DLC. At this level the contract is lively.
Execution
Through the lifetime of the contract there are three ways in which the mortgage could be settled, both at expiry or throughout its lifetime. Firstly, the lender can execute the DLC with the borrower’s adaptor signature, and an attestation of the present worth from the oracle(s). Secondly, the borrower can execute with the lender’s adaptor signature and an attestation from the oracle(s). Lastly, the borrower can repay the mortgage on the alt-chain, enabling them to assert again bitcoin collateral when the lender claims their compensation and stablecoin collateral. All of those execution paths disperse the suitable quantity of bitcoin to each events based mostly available on the market worth attested to by the oracle(s).
The compensation path makes use of the second hash preimage that the lender generated throughout the setup. The DLC script is modified permitting the borrower to assert again the collateral at any time throughout the contract lifetime so long as they’ve the preimage to that the lender has generated. On the alt-chain, the stablecoin contract can be established to require the lender to disclose that preimage to assert again their compensation and collateral.
This building for compensation is added to cope with the motivation the place a compensation is made, however the lender doesn’t finalize the compensation as a result of the curiosity fee on the mortgage excellent is bigger than the curiosity that could possibly be earned from them issuing a brand new mortgage. That is additionally the rationale that the lender is required to collateralize the alt-chain contract with additional stablecoins, creating an incentive for them to redeem a compensation. With out doing so, they can’t declare the collateral again, thereby creating an incentive for them to honor the compensation and launch the bitcoin collateral even when there’s a monetary incentive because of the curiosity funds to not accomplish that.
As soon as the lender releases the preimage to assert again the compensation and the stablecoin collateral, the borrower is then able to unilaterally spending the DLC output through the use of the launched preimage. This ensures that the borrower is ready to unilaterally reclaim their bitcoin collateral after the lender takes possession of their mortgage compensation.
Liquidation and Secure Guards
Just like the DLC Markets proposal, Lava helps a liquidation process. Within the case that the oracle attests to a worth that’s beneath a pre-defined liquidation stage, pre-signed transactions similar to the liquidation occasion can be utilized by the lender to assert everything of the collateral. That is to ensure that throughout the occasion of a large worth swing that lowers the collateral worth past the mortgage worth, the lender is able to liquidating it when essential to cowl the stablecoin worth the borrower claimed. In any other case, they could possibly be confronted with the danger of ready till the contract expiry and being caught with bitcoin that’s much less priceless than what they’ve lent out, leading to a monetary loss for the lender.
Along with the liquidation process, there’s additionally an emergency restoration possibility out there lengthy after the contract expiry. Throughout arrange signatures for pre-signed transactions lengthy after the contract expiry are exchanged. These are used within the occasion that the oracle(s) fail to ship signatures on worth attestations, or within the occasion that the borrower stops cooperating with the lender, or vice versa.
The lender is able to utilizing one among these to assert everything of the bitcoin collateral within the occasion the oracle(s) don’t attest to the value, or the borrower turns into non-cooperative in that case. That is to make sure that the bitcoin within the DLC is rarely liable to being burned. For related causes, a transaction timelocked for lengthy after the lender’s is obtainable. This enables the borrower to finally declare again their collateral if the oracle(s) and lender change into unresponsive.
Conclusion
By barely modifying the DLC protocol to incorporate a fundamental hashlock, and the introduction of the liquidation mechanism just like DLC Markets, the Lava protocol has created a variant of DLCs completely suited to bitcoin collateralized lending. Whereas the dependence on oracles nonetheless exists, like with any DLC protocol or software, the entry and exit of the mortgage is totally atomic and trustless between the borrower and lender.
This proves an immense quantity of worth in subtly tweaking current Bitcoin contract buildings to suit particular use circumstances, and gives a pathway to assembly a broadly demanded want within the ecosystem that doesn’t current the systemic danger of instability that centralized equivalents created previously.
