This post was written by Tim on Mar 29, 2022

An Introduction To The State Connector | Songbird Network

Scroll to the bottom for the 5 minute video.

Bridging assets between individual blockchains is inherently unsafe. As Vitalik “Vit-al-ik” Buterin says, the safest option is to keep blockchain-native tokens on their own blockchain. This is his view because of current bridging solutions having security concerns such as 51% attacks opening the possibility to double spending or the centralisation of bridges such as BitGo who holds BTC when wrapping it.

But what if we could mitigate the centralisation and security issues? Well… two words.. “State Connector”. This is Flare Networks solution to Vitaliks concerns and truly could close the gap between blockchains and host next generation interoperability.

Now.. something very important about the state connector.. While it’s a protocol which will drive the next generation of bridged assets, it has far more capability allowing for more complex interoperable applications as it has the ability to query any kind of data on another blockchain or even off chain in the real world! And to enable more data sources or blockchains, only an update made on Flare is required, not the underlying data source or blockchain making it very scalable. These additions can be voted in through governance.

The state connector boasts its ability to integrate with as many blockchains as possible which allows decentralised app developers to have access to multi-chain data, all from one location..

This is so game changing because the state connector does not require trust in centralised third parties or require infrastructure to be deployed on other blockchains to allow communication - unlike current solutions. It also has the ability to query the full history of a transaction to prove its validity - which just isn’t possible with solutions using technology like SPV (Simplified Payment Verification).

To allow all this to work Flare has introduced “Attestation Providers” who are a decentralised group and operate alongside Flare’s FTSO data providers and validators. Anyone can become an attestation provider with no capital requirement and their job is to confirm data proof that they receive. Basically checking over any and all data that network participants request from the state connector. This group of attestation providers can be defined by each Flare Node but also a default set is provided who meet the minimum requirements to make confirmations - that means they contribute the the outcome of the state connector. So while not all attestation providers will confirm state connector data, they will at the least act as watchdogs to ensure the default set is acting honestly which you’ll see why is some important shortly.

At the core of the state connector is its branching protocol, which deserves its own video to explain, but the concept allows each and every Flare node to override the default decision from the state connector using its own local set of attestation providers that it trusts. Since the branching protocol guarantees binary outcomes (correct or incorrect), the node will either agree or disagree with the state connector. This is important because if it doesn’t agree, the node will fork into a new branch and not accept unagreed data, maintaining what it believes to be the correct state of the Flare Network and safely halt.

If halted, the node operator will intervene and decide whether their node had made a mistake, which may mean updating their local attestation providers, and if a mistake was made, then they can simply switch back to the default branch and continue operating as normal.

An important use case of the node halting is to allow node operators of certain applications such as exchanges to decide the next step to take. If the node didn’t halt, for example they followed the wrong branch, they may be accepting transactions that shouldn’t have occurred. This is because the default branch continues to operate, processing blocks, until the default attestation provider set is corrected. So if the default branch is in fact incorrect, it will move backward and switch to the correct branch. This is however a rare occurrence which would require more than 50% of attestation providers to be faulty.

With this concept in mind, we can safely assume that an independent node operator will always stay on the correct branch of the Flare Networks state if it is correctly attesting and will temporarily stop if an issue with the networks state is detected.

This is the security innovation protecting new applications and protocols coming to Flare such as the FAsset system which aims to tap into the $1.4T of crypto tokens which are unable to run smart contracts. This is the portion of crypto missing out from participating in today’s decentralised economy.

All in all, it’s an amazing tool which will power trustless, universal bridging of data and assets.