Ethereum 1.x: On blockchain interop and scaling

Vlad Zamfir and Vitalik Buterin present their latest research on blockchain interoperability and scaling as part of DEVCON 0.

The Path to the Ethereum Light Client

Vitalik Buterin and Dr. Gavin Wood take a look at the Ethereum light client roadmap.

Scalability

Ethereum's Dr. Gavin Wood moderates a panel with Vitalik Buterin, Martin Becze, Dominic Williams and Vlad Zamfir on scalability with Ethereum.

The Pathway to Ethereum Adoption

A panel focusing on "The Pathway to Ethereum Adoption" with Vinay Gupta (https://twitter.com/leashless), Gavin Wood (https://twitter.com/gavofyork), Joseph Lubin (https://twitter.com/ethereumJoseph) and William Mougayar (https://twitter.com/wmougayar).

Scalable Blockchains & Asynchronous Programming

Ethereum's Vitalik Buterin presents on scalability and asynchronous programming.

Universal Hash Time

Jeff Coleman of Ledger Labs (http://ledgerlabs.io/) presents on the Universal Hash Time + State Channels.

The Mauve Revolution

Proof of stake and sharding present two of the biggest upcoming milestones in the ongoing development of the Ethereum protocol. Proof of stake offers the promise to greatly reduce the cost of consensus and increase security guarantees, while sharding presents an approach to allow on-chain scaling to tens of thousands of transactions per second while still retaining a network that can, if needed, run on nothing but a sufficiently large set of consumer laptops. The Casper approach to proof of stake also introduces a number of novel concepts, including consensus-by-bet and fork choice by value-at-loss.

A Fast and Scalable Blockchain for Enterprise Users

Almost every bank and major financial institution inChina as well as across the world is eager to revamp their computing infrastructure through blockchain. What a blockchain designed for them should look like? Is it enough to replace PoW with PBFT? What else can we do to leverage the resources enterprise users have? You will find the answers in CITA.

The Raiden Network

Raiden is a payment channel technology for fast, cheap, scalable off- chain token transfers. Introduction for developers planning to prototype applications on top of the Raiden Network testnet as well as μRaiden.

Build and Operate Internet-Scale Ethereum dApps on Celer Network

Current Ethereum dApps have low throughput because each operation needs to be processed by the vast majority of nodes to reach on-chain consensus. Off-chain scaling techniques such as state channel are able to support truly scale-out dApps with better privacy and no compromise on the trust-free guarantee. Despite its high potentials, off-chain scaling is still in its infancy with challenges remaining unsolved. For example, how to construct state channels that support arbitrary state transitions with minimal on-chain operations? How to route payments to achieve high throughput in an off-chain network that is fundamentally different from data networks? How to help developers to easily build and operate scalable off-chain dApps? How to guarantee that off-chain states are always available for possible disputes? In this talk, we will describe how Celer Network meets these challenges. Celer embraces a layered architecture with clean abstractions that enable rapid evolution of each individual component, including generalized state channels that supports fast and generic off-chain state transitions; a provably optimal payment routing algorithm that achieves orders of magnitude higher throughput compared to state-of-the-art solutions; a powerful development framework and runtime for off-chain dApps; and an incentive-aligned mechanism that provides stable liquidity and high off-chain state availability.

Building a state channel application

State channels are a great tool for building high-performance, low-cost dapps today. By moving some of your dapp behaviour off-chain you can save transaction fees and confirmation times, while continuing to bootstrap security and trustlessness from the underlying blockchain. In order to understand how an application can benefit from state channels, it’s important to understand the mechanics behind them. The good news is that once you’ve managed to model part of your application as a state channel interaction, there are already tools available to help make the switch.In this interactive workshop, we will dig into an existing state channel application. We’ll cover the fundamentals of state channels, as well as the main design decisions behind modeling the interactions and architecting the application. You’ll test your understanding by completing key sections of the code, leaving the session with a functioning state channel application, built with react on top of the force-move games framework!

Cryptoeconomics at Scale

The next wave of internet applications will not only compete on functionality, but also incentives. With cryptoeconomic research we are witnessing the beginnings of incentive analysis being applied to the architecture of internet protocols. As this body of research grows, common methodologies are beginning to emerge. These methodologies are also beginning to be composed to produce even more sophisticated and scalable protocols. This talk provides an overview of these cryptoeconomic methodologies and calls for help in the quest to build a fairer web.

Fraud Proofs: Maximising Light Client Security and Scaling Blockchains with Dishonest Majorities

Light clients are nodes which only download a small portion of all of the data in a blockchain, and try to use indirect means to verify that a given chain is valid. Typically, instead of validating block data, they assume that the chain favoured by the blockchain's consensus algorithm only contains valid blocks, and that the majority of block producers are honest. By allowing such clients to receive fraud proofs generated by fully validating nodes that a block violates the protocol rules, we can eliminate the assumption that the majority of consensus-participating nodes are honest, and instead assume that there is at least one honest fully validating node that can distribute fraud proofs within a maximum network delay, and a minimum number of honest light clients to reconstruct missing data from blocks. Fraud proofs and data availability proofs are key to enabling on-chain scaling of blockchains (e.g. via sharding or bigger blocks) without significantly reducing the ability of end-user wallets to have assurance that all on-chain data is available and valid. We present, implement, and evaluate a novel complete fraud proof and data availability proof system. Research paper draft (work-in-progress): https://www.dropbox.com/s/3zj3burdfrw5v69/fraudproofs-paper.pdf Data availability code: https://github.com/musalbas/rsmt2d Fraud proofs prototype (work-in-progress): https://github.com/asonnino/fraudproofs-prototype

From Scalability to Inclusion: Enabling Mass Adoption

David Lee Kuo Chuen gives his talk on Enabling Mass Adoption.

FunFair Technologies' Fate Channels: Lessons learned Implementing State Channels

Jeremy Longley, CTO of FunFair Technologies, will offer a post-mortem on the delivery of their own version of state channels, Fate Channels, to Mainnet. There have been significant challenges along the way, and there's likely to be many more to come as their use scales up. Having deployed a flexible and creative approach, Jeremy will outline how others can bypass these challenges and embrace state channels as best they can.

INCUBED - A trustless incentivized decentralized remote node network

To enable smart devices of the Internet of Things to be connected to the Ethereum blockchain, an Ethereum client needs to run on hardware. While running a full-node or even a light-client on most IoT devices with low performance or restricted resources is not possible or meaningful, today's state-of-the art solution uses a remote client. By using distinct remote-nodes, the advantages of a decentralized network without being forced to trust single players are undermined and there is a risk of malfunction or attack because there is a single point of failure.With the presented Trustless Incentivized Decentralized Remote Node Network, in short INCUBED, with a stateless minimal verification client it is possible to establish a decentralized and secure network of remote-nodes, which enables trustworthy and fast access to blockchain for a large number of low-performance IoT devices.

Introducing Pantheon, a Mainnet Java Client - Demo & Roadmap

This will be the launch of Pantheon, a Java client built for mainnet with an eye for meeting enterprise requirements. Having multiple, performant clients is important to the long-term viability of the Ethereum ecosystem, and enterprise adoption will draw greater resources. This will be a demo of the new client with a walk-through of our roadmap. By introducing a client in Java and building it open source, we’re hoping to draw in the massive Java community into the Ethereum ecosystem, support research and innovation led by the Ethereum Foundation, and add extensions to meet enterprise needs on privacy, permissioning, and others. We will also talk about some of our research efforts on top of Pantheon.

Less Gas, More Fun: Optimising Smart Contracts through Yul

Due to the relative simplicity of the Ethereum Virtual Machine, it is possible to perform heavy analyses in order to optimize bytecode. The jump operations are a main obstacle for this, because they might require a preservation of all basic blocks in the worst case. To overcome this, Solidity's new optimizer operates on an intermediate language called Yul, which is close to EVM bytecode (and also wasm) but abstracts jump operations through real function calls. Each of the many optimizing operations are simple local equivalence transforms whose effects can be inspected at any time and which in combination should be both more reliable and efficient than the classic optimizer.

Making Sense of Layer 2

This talk will be a high level overview of the state-of-the-art in "Layer 2" scaling tech. The goal is to give the audience a comparative understanding of techniques like state channels, plasma (and its various flavours), sidechains, etc. Introduce a basic taxonomy of layer 2 tech -What are the similarities and differences between them? -Comparative analysis - what is each technique good at and bad at? -Defining and explaining jargon used to discuss this tech -Distinguishing between "safety net preserving" techniques (plasma, state channels) and others (sidechains)

Mustekala Project: MetaMask to become a light client over libp2p

MetaMask Labs is doing research for the browser extension to become a light client running on top of libp2p. The project codename is Mustekala. As of now, we have fleshed out a comprehensive architecture (https://github.com/MetaMask/mustekala/blob/master/docs/architecture.md) of four layers, where we extract data from devp2p synchronized clients and make it available in libp2p using the IPLD format. Upstream, an overlay network of peers (named kitsunet) shares this information, allowing data redundancy and decentralization at face value. In terms of vision, in a close future low resource devices (browsers, mobile and IoT) should stop depending on JSON RPC communication with ethereum nodes. This is a huge problem today, as nodes became GB-sized machines. Last but not least, every MetaMask user will become a peer of a bigger and more inclusive ethereum network.

P2P Networking in Ethereum 2.0

Sharding and Casper promise to greatly improve performance, sustainability, and security of the Ethereum blockchain. Alongside a novel and much-discussed consensus protocol, they also entail fundamental changes to the requirements and constraints imposed on the peer-to-peer (p2p) networking layer. In this talk we report on ongoing research as well as the current implementation state of the latter. We begin by defining key qualitative and quantative properties the network should have. Then we discuss several options for both node discovery and gossip protocols, comparing their performance on the basis of simulationresults. Finally, we give an update on the current state and future developments of protocol implementations.

Plasma Implementers Call Live!

The Plasma Implementers Call is a biweekly call which discusses the cutting edge of Plasma research. We will be doing a LIVE session! This is a great group of 9 people:  Joseph Poon, Karl Floersch, Kelvin Fichter, Dan Robinson, David Knott, Xuanji Li, George Konstantopoulos, Alex Vlasov, & (if I can convince him) Vitalik! You can take a look at the YouTube channel here: https://www.youtube.com/channel/UCG2MeKuKDJRK4gFNk-dQuZQ  Please subscribe! ;)

Perun: Virtual Payment and State Channel Networks

In this talk, we will present the Perun Network: a general framework of 2nd layer protocols supporting off-chain payments and arbitrary smart contract off-chain execution. Perun allows its users to execute contracts off-chain via complex state channel networks possibly involving many intermediaries over which contract execution can be routed.   One distinctive feature of Perun is that its channels can be virtual, meaning that once a virtual channel is established transactions can be executed even without involvement of the intermediaries. This enables nearly real-time transaction execution with minimal latency at negligible costs. Moreover, privacy of transactions is significantly improved. An additional property of Perun is that its security is backed up by formal proofs using state-of-the-art scientific methods from cryptographic research. Besides presenting the main conceptual ideas of our system, we will outline some of the the major scientific challenges that need to be addressed when designing secure and efficient 2nd layer protocols. Further information available at https://perun.network/

Plasma Cash: Towards improved Plasma constructions

Plasma is a technique which is used to increase Ethereum transaction throughput, while maintaining network decentralization and security. We focus on the variant of Plasma called Plasma Cash, which allows for highly performant sidechains in production, today. We discuss Plasma Exits and Challenges as well as explore the User Interface choices for Plasma Apps. We go over the challenges encountered during the development and final implementation of a Plasma chain and contract. The presentation will highlight the advantages and disadvantages of using Plasma Cash, as well as practical examples of Plasma for Non Fungible Tokens and gaming. Finally, we'll talk about edge-cases such as griefing attacks, and future work towards making Plasma implementations more efficient, such as fast exits through liquidity providers, coin checkpointing through Plasma XT and arbitrary coin denominations through Plasma Debit. The audience is expected to walk away with a detailed understanding of how Plasma Chains should be built as well as the inner workings of the Plasma Cash technique. More experienced individuals who understand but are not following Plasma actively are expected to walk away with an overview of the current status of Plasma research and development, and motivated to tackle the existing open research problems.

PISA: Arbitration Outsourcing for State Channels

PISA alleviates the "always online assumption" for all channel protocols and it is necessary for Raiden, L4, Perun, etc. State channels are a leading approach for improving the scalability of blockchains and cryptocurrencies. They allow a group of distrustful parties to optimistically execute an application-defined a program amongst themselves, while the blockchain serves as a backstop in case of a dispute or abort. This effectively bypasses the congestion, fees and performance constraints of the underlying blockchain in the typical case. However, state channels introduce a new and undesirable assumption that a party must remain on-line and synchronised with the blockchain at all times to defend against execution fork attacks. An execution fork can revert a state channel’s history, potentially causing financial damage to a party that is innocent except for having crashed. To provide security even to parties that may go offline for an extended period of time, we present Pisa, a protocol which enables such parties to delegate to a third party, called the custodian, to cancel execution forks on their behalf. To evaluate Pisa, we provide a proof-of-concept implementation for a simplified Sprites and we demonstrate that it is cost-efficient to deploy on the Ethereum network. Blog+Paper: http://hackingdistributed.com/2018/05/22/pisa/

Practical Plasma: Gaming

Talk will explore how Plasma Cash is changing the blockchain gaming landscape. Viewers will come away with a strong understanding of how to add advanced functionality like real time battles and crosschain token transfers to their existing games. Also we will explore how Plasma Cash enables use of sidehains to speed up gaming. What are the UI/UX difficulties of Plasma Cash? What would having wallets on multiple chains look like. Can we have automatic sign transactions for users? First we will delve deeper into L2 solutions like sidechain and state channels. We will see how plasma cash enables token transfers to sidechains, enabling the game to be fully run on the secondary layer. We will compare from a high level some common L2 solutions. We will walk through the UI/UX choices, how existing wallets interact with Plasma contracts. Then we we will delve into the tradeoffs in UI to speed. Finally we will tie everything together, by showing a working game that uses plasma, on a sidechain. So the audience can get the feel of what the end result of all this work would look like. What kind of games are possible and open up ideas for their future titles.

Raiden Network: Getting to a production ready payment channel network

The Raiden Network is the payment channel network for Ethereum aiming to help scale Ethereum payment and all Dapps that utilize Ethereum for payments and rely on no on-chain side effects of the payments. There will be a small explanation of what is payment channels and a payment channel network, an explanation of the raiden network protocol and a demo of using Raiden (hopefully by then live on the mainnet). We will close with future plans, expansion of the protocol and showcasing potential applications.

Snarks for mixing, signaling and scaling

There is general interest in the ethereum community to scale ethereum by moving dapps inside snarks. The key to do this is to make an efficient signature function available inside a snark. We present this signature function https://github.com/barryWhiteHat/baby_jubjub_ecc designed to work efficiently inside a snark. Furthermore we describe an architecture to scale ethereum using snarks. We discuss the trade offs required and compare them to building a dapp inside the evm.

SpankChain: Payment Channels in Production

The original custodial payment hub architecture; Our motivation for upgrading to a non-custodial hub; The new perun-style hub architecture; How we conducted the upgrade; An overview of features: Streaming payments, Currency auto-conversion (+ price negotiation), 2-token exchange, Custodial payments, Fees; A discussion of various design decisions: Payment Channels vs. Plasma, Perun vs. Hashlocks, Unidirectional vs. Bidirectional Virtual Channels, Emphasizing the “Card”, de-emphasizing the wallet; BOOTY Maximalism vs. ERC20 agnosticism; Future Roadmap; Networked hubs; State channels; Integration into Wallets like Gnosis Safe; Delegated signing keys / permissions; Anticipated Ecosystem Impact; SDK - Everyone gets payment channels; As a foundation for state channels; As a focal point for experimentation.

State Channels on Ethereum with Counterfactual

State channels are a critical "layer 2" scaling technology for ethereum. State channels let users conduct "off chain" transactions rapidly, without waiting for blockchain latency, but with each transaction still considered a "final" transfer of digital value or other valuable "state". However, they are difficult to engineer - today, many dapp developers have had to "roll their own" channels. Counterfactual aims to make it easy for developers to use channels in their applications, and get started making secure, scalable, performant ethereum dapps today. This talk will cover: - Overview of state channels technology - Introduction to the Counterfactual framework - How developers can get started using Counterfactual today

SWARM Team Update

Swarm aims to be the native data storage and content distribution infrastructure layer of the "Web 3.0".Since our last update at Devcon3 in Cancun, Swarm has seen major progress in its codebase. The long awaited network rewrite has been completed and several new features have been merged. In this talk members of the Swarm Team will present quick updates. For example, here are some of the updates we'd touch upon: -Encryption - Since the 0.3 release Swarm supports native encryption on the chunk level. Daniel will present a quick overview. -Access Control Trees - newly introduced in Swarm is the support for Access Control Trees. This feature increases the utility of Swarm to a wide range of use cases. Elad will sketch the main features. -Swarm Light Client - The requirements and limitations of the mobile phone present unique challenges for Swarm and we have begun to address them with the Swarm Light Client. Attila will give an update on this project. -PSS - The PSS protocol has matured significantly since last year. Lois will give the update. -Spam prevention in Swarm - new ideas for countering a flood of bad data. (dani & Aron) -Databases in Swarm (Viktor)

The EEA Technical Roadmap

Ron Resnick and Conor Svensson from the EEA present their technical Roadmap.

The Promise of Trusted Compute for Ethereum Scalability, Decentralization and Privacy

The Ethereum community has well known reservations about Trusted Compute and support those concerns. As Ethereum is becoming the dominant chain, scalability, decentralization and privacy will be the most important challenges. With the emergence of technologies such as PoS, Plasma and increasing use of staking and voting as design tenets, we believe Trusted Compute designed and deployed with decentralization as the objective can play a significant supporting role in not only preserving but also extending and democratizing the promise of decentralization. The presentation and related demonstrations are designed to engage with and trigger conversations within the Ethereum  community on the relevance of Trusted Compute.

Turbo-Geth: optimising Ethereum clients

As Ethereum network becomes gets more and more use, the load on the system grows, and the scalability becomes the primary concern. While concepts like Plasma, State Channels, and Sharding offer medium to long term solutions, client software optimisation have a potential to create enough runway in the short term. Turbo-Geth is an experiment to challenge various design choices made in major Ethereum clients and see the outcome. It is currently a fork of go-ethereum, but hopefully the insights are applicable to other client implementations too. This presentation will report on main experiments, findings, benchmarks, and the current state of Turbo-Geth project.

Optimistic Execution: Putting the Internet on Ethereum

Ethereum can serve as an arbiter of trust for the entire internet. To make this a reality we'll have to scale. Our best bet to scale is constructing a comprehensive layer 2.What do plasma, state channels, optimistic rollup, & ETH2 have in common? Optimistic execution! Or in other words, they each make inferences about future Ethereum state based on local information--think fork choice on top of a state machine. Using this concept we construct the Optimistic Virtual Machine (OVM), baking inference logic directly into wallet & application software. In this talk we discuss how the key role trust will play in the internet--from DeFi to timestamping--and how we can build the underlying infrastructure to support internet scale. These are exciting times for blockchain infrastructure. Now we just need to solve identity & UBI -- easy!

Scalabilty with zKSNARKs

Scalabilty with zKSNARKsThis session will introduce iden3’s zkSNARKs implementation and how it will be used at two scenarios: For the trustless relayer implementation at the identity management environment, allowing the identities to perform claims without cost at big scale.And the rollup project for Ethereum scalability, allowing verifiable computation off-chain to increase transaction throughput