Q&A

What is Swingby Skybridge?

Swingby’s bridge protocol, Skybridge, builds trustless bridges between Bitcoin, Ethereum, Binance Chain, and other blockchains secured by a network of node groups that execute fast token swaps using ‘multi-party computing’ and layer 2 technology. Skybridge allows users to move Bitcoin tokens between the Bitcoin, Ethereum, and Binance Chain without relying on a central custodian, opening up a whole world of DeFi capabilities such as liquidity pooling and DEX trading with an easy-to-use user interface. Swingby plans to launch its Ethereum MainNet in December 2020, bringing Bitcoin to a vibrant ecosystem, with over $1BN BTC capital locked up in DeFi contracts. Building on exciting partnerships with projects such as Elrond, Waves, and Kira Protocol, Swingby aims to expand its reach to other chains and projects, adding support where the most value can be created.

Why will Bitcoin to Ethereum be the first bridge?

Swingby plans to add support for many more chains in the future. However, Bitcoin and Ethereum were chosen as the first bridge pair due to the popularity of ERC20 bitcoin tokens in the DeFi space and Bitcoin's market capitalization. Currently, it is impossible to move your native bitcoins into WBTC on Ethereum without the use of a centralized party (e.g., a centralized exchange), despite WBTC being, by far, one of the largest tokens (by market cap) on Ethereum. Skybridge solves this problem. However, Swingby is token-agnostic and its teams are enthusiasts to support the diversification of protocols. Thus, additional bridges with other Bitcoin tokens on Ethereum are being considered at the moment, once they match the required technological standard while being supported by market demand.

How can developers use Skybridge?

As of now, a developer who builds on Ethereum a set of smart contract can only interact with assets circulating on the Ethereum network. By integrating with Skybridge, all DeFi platforms such as DEXs, lending & borrowing protocols, and other AMM protocols can begin utilizing digital assets that weren't available on the network. ‍ What if you could swap your bitcoins for USD stablecoins in one click? With Skybridge, it becomes possible to route cross-chain orders with existing protocols, reaching new users on new blockchains. The world of crypto that we know and love suddenly becomes open.

Is this technology reliable? Why hasn't anyone used it before? Has its security been verified?

Threshold Signature Scheme ("TSS") is a relatively new technology with many advantages that works well for cross-chain swaps. This technology is used by at least a handful of other open-source projects. As all new technologies, it will require a phase of early-adopters where the usefulness and security are tested and confirmed. A full security review of the underlying cryptography used on Skybridge was carried out by Kudelski Security, a division of the Kudelski Group, and completed in October 2019. A copy of this report may be found here:

https://github.com/binance-chain/tss-lib/releases/download/v1.0.0/audit-binance-tss-lib-final-20191018.pdf

Since there are so many problems with DeFi, do you think anyone will continue to use DeFi? Why would people use and trust your new project?

Our goal is not to become a DeFi project, but rather to bridge a variety of DeFi applications across chains. That being said, we are supporters of the DeFi movement and acknowledge both the benefits and risks associated with such protocols. Early adopters will continue using DeFi at the stage we are at today; carrying inherent risks. However, we believe that when security and stability are proven across a longer time frame (and when it becomes easier to use), that’s when we will see users increase.

What protection does Swingby Skybridge have in place to prevent Sybil attacks?

A Sybil attack on Swingby Skybridge has two important thresholds that need to be considered: (1) when attacker control (n-t+1) nodes, and (2) when attacker control t nodes, where n is total number of nodes and t is the threshold number for signing transactions. A malicious actor controlling (n-t+1) nodes can in practice halt all swaps. If so, good actors would be unable to reach the threshold t required for signing. However, this type of attacks would bring no economic gain to the attacker, be expensive to attempt, and would be mitigated by a regroup mechanism and node assignment prioritized by node age. Sybil attacks with economic motive needs to attain t nodes. This is mitigated primarily by node assignment through node age.