There’s a new kid on the block — RollApps. RollApps are Dymension’s solution to scaling. They are application-specific blockchains minus the consensus overhead, leaving just a highly scalable execution environment. RollApps use a common shared security framework, the Dymension Hub. The IBC-enabled hub allows for a connection to all other IBC-enabled chains, as well as communication between deployed Dymension RollApps, creating greater network effects as more applications are deployed.
RollApps are autonomous, think Texas, not USA. Texas is free to focus on attracting quality companies to head over and build (Howdy Elon!), all while not having to directly deal with the security overhead of uncle sam’s army.
Back to crypto, what do we mean by autonomous? Each Dymension RollApp maintains its own token as the network fee. So no more paying Ethereum when you are using Curve (think more use-cases and value accrual to Curve token holders). Users pay fees to the RollApp rather than Dymension, boosting app sustainability. At this stage some may wonder what role does Dymension play in all of this? RollApp security and agreed upon state of the application is maintained by the Dymension settlement layer which requires RollApp sequencers (the operators of the application) to stake DYM tokens to participate as part of the ecosystem.
As the name implies RollApps are app-specific rollups which come with their own set of advantages compared to blockchains — namely orders of magnitude of higher throughput and much lower latency (If you’re not too familiar with what are roll ups take a look at our previous article). In short, they execute transactions off-chain and post data and state updates on-chain. With the data posted, anyone can submit a fraud proof and earn slashing rewards in case of a fraudulent state update.
RollApps operate under fraud proof design allowing for greater scale and relying on just one honest participant for a well functioning system. One honest participant means that only one actor needs to prove that a malicious action was committed by the RollApp sequencer and if so the sequencer gets slashed. In technical jargon this is known as 1 of N trust assumptions¹. You can compare this to the usual N/2 of N consensus assumptions that PoW blockchains operate under.
To give a bit more context on where RollApps come from, we need to look at the Cosmos ecosystem. Cosmos is a decentralized network of independent, parallel blockchains (App-Chains) powered by Tendermint. One of the main factors that makes Cosmos’ tech extremely robust is the segregation of application logic and the consensus and networking. Although the Cosmos app-chain design is considered monolithic, it showcases the advantages of a modular architecture. This approach is amplified with RollApps, as the system is completely modular.
App-Chain Diagram
In many ways RollApps are very similar to App-chains. They too are a set of interconnected independent chains that compose a wider network. Similarly to App-chains, RollApps are also application-specific, and they too have their own token which can be used to pay for network fees. There will even be an SDK for rollups, the RollApp Development Kit (termed RDK). But, as much as they are alike, there are still a few major differences which constitutes the reason for their creation. Namely, allowing for higher throughput, lower latency and substantially easier bootstrapping than any monolithic blockchain.
So, a disaggregated execution layer from the settlement layer? Astute readers might think of Polkadot, but unlike Polkadot’s para-chains, deploying a RollApp is permission-less, does not require participating in an expensive auction and slots are virtually limitless. Similar to Cosmos, Dymension believes deployment should be made as easy as possible to encourage a thriving ecosystem. Dymension aims to enable developers to deploy RollApps as easy as deploying an AWS instance.
By design, Dymension’s settlement hub is a lean machine. In-line with the modular blockchain framework, data is passed down to a disaggregated Data Availability Layer² and a merklized state root is passed to Dymension’s settlement layer. Dymension’s validators are responsible for maintaining the current state and handling any fraud disputes or malicious RollApp sequencers. For example, if a RollApp is censoring its users, the user can force a RollApp to accept a transaction by interacting directly with the Dymension Hub.
In conclusion, RollApps architectural advantages mostly resemble the familiar app-chains, yet RollApps also possess impactful improvements for the future of decentralized applications. Dymension’s team is looking forward to the next steps in this exciting building process as we edge closer and closer to the release of the litepaper and a following testnet. Dymension welcomes new enthusiastic community members as a new optimal design space for developers is in the workings.
Join us:
⌘ Website: https://www.dymension.xyz/
⌘ Twitter: https://twitter.com/dymension
⌘ Telegram: https://t.me/dYmensionXYZ
⌘ Discord: https://discord.gg/dymension
Sources
1 https://vitalik.ca/general/2020/08/20/trust.html
2 https://medium.com/blockchain-capital-blog/wtf-is-data-availability-80c2c95ded0f
