Video & slides from #ETHBerlin: Introducing OpenST Mosaic Protocol: Running meta blockchains on Ethereum to scale DApps to billions of users

Mosaic is token sharding at layer 2 that will work right now on Ethereum v1.0 to scale DApps — with an open, staked validator set, and asynchronous finalization of transactions on Ethereum.

On Friday 7 September, 2018 OST Chief Blockchain Scientist Benjamin Bollen presented OpenST Mosaic Protocol for the first time at ETHBerlin.

ETHBerlin was a fantastic community-driven event featuring substantive tech talks, workshops, and an incredibly inspiring hackathon. Huge props to the ETHBerlin community leaders for your tireless efforts. You rocked it! That was one of the best developer events we’ve ever participated in!

ETH Berlin marked the public introduction of OpenST Mosaic — the first time we presented the OpenST Mosaic Protocol in full details.

OpenST Mosaic is a protocol for scaling DApps on Ethereum to billions of users. While much of the current scalability work on Ethereum is focused on off-chain or hybrid on-chain/off-chain solutions, or preparing for ETH v2.0, OpenST Mosaic is on-chain token-sharding at layer 2 that will work right now on ETH v1.0 (and later on ETH v2.0 when it’s ready).

  • OpenST Mosaic is a consensus protocol to run meta-blockchains on top of Ethereum.
  • Each meta-blockchain runs in parallel and injects an additional state space into Ethereum.
  • Each meta-blockchain is secured by Ethereum with an open, staked validator set.
  • All transactions on meta-blockchains are asynchronously finalised and committed onto Ethereum.
  • Mosaic has a message-passing protocol between Ethereum and meta-blockchains (later directly between meta-blockchains).

To put Mosaic into context vs. other important Ethereum scalability projects:

  • Sharding + Casper are the work behind “Ethereum 2.0” to scale Ethereum in the future (2020 to 2022), first by a hybrid POW/POS consensus mechanism, and then ultimately moving to a full POS consensus mechanism and sharding. Sharding is intended to provide parallel processing of transactions. Each node can process its shard separately, while together nodes can work in parallel, increasing the network’s bandwidth and transaction speed by several times.
  • Plasma is a body of work designed to scale each DApp off-chain. Plasma is a technique for off-chain transactions while relying on the underlying Ethereum blockchain to ground its security. Other off-chain scalability projects include state channels and Truebit.
  • OpenST Mosaic is a new on-chain layer 2 specification for token sharding — building on many of the concepts behind Casper and Sharding but enabling them to work now, on-chain, as a layer-2 solution.

Here is the video from Ben’s talk on OpenST Mosaic.

Here are the slides in-full from the presentation:

At the end of the presentation we present an update on the current state of OST and OpenST development, and what’s next.

Current Status:

  • OST KIT & OpenST 0.9.2 used by 120+ external developer teams on Testnet
  • OST KIT & OpenST 0.9.2 used by 10+ external partners on Mainnet — 3 months ahead of schedule
  • OpenST 0.9.3 (cross-chain messaging) — completed
  • OpenST 0.9.4 (decentralized keys engine & token rules engine) — in progress

We are currently introducing OpenST Mosaic at several events like ETHBerlin to solicit community feedback. Upcoming:

  • Upbit Developer Conference, in South Korea, on September 13th
  • Hashed Lounge: Origin Protocol & OST Simple Token on September 14th in Seoul

Q3 2018

  • Publish OpenST Mosaic Paper for Community Feedback

Q4 2018

  • Continue Mainnet testing of OST, OpenST Protocol


  • Mosaic alpha
  • Mosaic beta — warm up validator pool
  • Widespread Deployments of OST, OpenST, Mosaic to mainstream businesses and DApps
  • smart contract calls across auxiliary chains
  • 2nd-order meta-blocks (aux-on-aux-on-ETHv1.0 or v2.0)


  • Mosaic fully released to decentralised validator pool

The complete OST & OpenST Project roadmap can be viewed here.

Community Feedback

We welcome all questions and feedback about OpenST Mosaic and about any aspect of the project. Please visit our Github, message us on Twitter, chat with our developers on Gitter, email Ben directly at ben at ost dot com, or connect with us on Telegram.

About OST

OST blockchain infrastructure empowers new economies for mainstream businesses and emerging DApps. OST leads development of the OpenST Protocol, a framework for tokenizing businesses. In September 2018 OST introduced the OpenST Mosaic Protocol for running meta-blockchains to scale Ethereum applications to billions of users. OST KIT is a full-stack suite of developer tools, APIs and SDKs for managing blockchain economies. OST Partners reach more than 200 million end-users. OST has offices in Berlin, New York, Hong Kong, and Pune. OST is backed by leading institutional equity investors including Tencent, Greycroft, Vectr Ventures, 500 Startups.