What is Telegraph

Telegraph is a community-driven blockchain oracle that aims to make cross-chain communication for smart contracts across multiple blockchains both easily accessible and affordable.
Current blockchain bridge node networks keep their systems behind registrations and approvals, which in turn stifles innovation as smaller developers are unable to take their smart contracts to the next level. With Telegraph, developers will finally have a cross-chain bridge that they can integrate into their project with a few lines of code. No registration required. Rather than downloading the full blockchain, Telegraph validators will use external Full Node providers to communicate with the chains in question. This will keep the validators lightweight, and fast to set up.
The Telegraph oracle itself is an off-chain set of validator nodes that share control over multiple multi-signature smart contracts known as "ports". These ports act as relay points on each supported chain, and always require a threshold of validators to supply their signature in order to approve a transaction. Using this method, each validator is able to retain privacy with control over their own private keys while being able to sign the messages off-chain. This means that only one final transaction has to be sent to the destination blockchain, rather than one transaction from each validator.