Smart contracts on Ethereum are fully self contained and any information or access to off-chain data is restricted. Tellor solves this problem by creating a system where parties can request the value of an off-chain data point (e.g. ETH/USD) and miners compete to add this value to an on-chain data bank, accessible by all Ethereum smart contracts. Inputs to a data series are secured by a network of staked miners. The main Tellor smart contract creates a time series of each requested data series and aims to become the standard source of high value data for decentralized applications. This oracle, “Tellor”, utilizes similar incentive mechanisms to other cryptocurrency systems through the issuance of Tellor’s token, Tributes, that are used to request a particular data series from miners.
Wrapped Bitcoin Tokens (WBTC) is an ERC20 token fully backed by real BTC. The proof of reserves is on-chain, showing the exact 1:1 ratio between minted WBTC tokens and BTC stored by the custodians. A collaborative effort with a community of partners to bring Bitcoin to the Ethereum network will bring the stability and value of Bitcoin to Ethereum's expansive ecosystem of decentralized applications.