Link-O-tron-3000

Inspiration

We live in the past when it comes to sending crypto. You don't have a list of wallets of your contacts. Collecting wallet addresses is confusing and prone to clipboard and phishing attacks. With Link-O-Tron 3000, you don't even need to know the wallet address. Simply send a link through your preferred channel.

What it does

Tron-O-Links are a new crypto primitive. They are a way to send and receive crypto assets using passwords.

Send tron without knowing someone's wallet address They can claim the Tron-O-Link by entering the password They will receive the crypto asset

Send Tron to Link-O-Tron 3000.

Receive a secret link with a unique ID.

Send the secret link to a friend

Your friend can claim the Tron by clicking the link## How we built it

Challenges we ran into

Frontrunning was the greatest challenge with this. Our use case is a textbook example for frontrunning. Alice (sender) wants to send money to anyone who knows a specific phrase (claimer). How can you do that on the blockchain, where you can't store private data?

First, we thought about ZK proofs because they're super cool. But gas cost of proving a zk-SNARK is relatively high, so we transitioned to a much cheaper two-phase time-locked transaction mechanism (commit-reveal), which is also super cool. This has a smaller attack surface and is a more mature method of doing things. The way it works is this: when someone wants to claim funds, they make a deposit to lock the smart contract for 15 minutes to only allow retrievals to their address. The deposit only gets refunded if the claimer then submits the correct passphrase. The required deposit amount can be set by the sender. The two-phase mechanic prevents denial of service attacks and the deposits make DoS attacks very costly.

Accomplishments that we're proud of

We are very proud that this is an. This means setting up the smart contract completely non-custodially, and hosting the frontend as a single static file. This is pretty unusual, and we had to adapt the tooling to us.