Kyber Network Whitepaper

Thursday, May 10, 2018
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KyberNetwork A​ ​trustless​ ​decentralized​ ​exchange​ ​and​ ​payment​ ​service Loi​ ​Luu​ ​,​ ​Yaron​ ​Velner [loiluu,​ ​yaron]@kyber.network (v0.8,​ ​updated​ ​on​ ​27​ ​August,​ ​2017) Abstract. ​We design and build KyberNetwork, an on-chain protocol which allows instant exchange and conversion of digital assets (e.g. crypto tokens) and cryptocurrencies (e.g. Ether, Bitcoin, ZCash) with high liquidity. KyberNetwork will be the first system that implements several ideal operating properties of an exchange including trustless, decentralized execution, instant trade and high liquidity. Besides serving as an exchange, KyberNetwork also provides payment APIs that will allow Ethereum accounts to easily receive payments from any crypto tokens. As an example, any merchant can now use KyberNetwork APIs to allow users to pay in any crypto tokens,​ ​but​ ​the​ ​merchant​ ​will​ ​receive​ ​payments​ ​in​ ​Ether​ ​(ETH)​ ​or​ ​other​ ​preferred​ ​tokens. Although running on the Ethereum network, KyberNetwork’s roadmap includes supporting cross-chain trades between different cryptocurrencies using relays and future protocols like Polkadot and Cosmos. Ethereum accounts will be able to safely receive payment from Bitcoin, ZCash and other cryptocurrencies via our payment APIs, through this trustless payment service. Derivatives will be introduced to mitigate the exposure to the risk of volatilities for the users of KyberNetwork Crystals (KNC) and selected cryptocurrencies. This will allow users to participate in​ ​the​ ​price​ ​movements​ ​synthetically. 1

Table​ ​of​ ​contents 1.​ ​Introduction 1.1.​ ​Motivation 1.1.1.​ ​Risk​ ​of​ ​centralization 1.1.2.​ ​Lack​ ​of​ ​instant​ ​exchanges 1.1.3.​ ​Problem​ ​of​ ​existing​ ​decentralized​ ​exchanges 1.1.4.​ ​The​ ​problem​ ​of​ ​having​ ​many​ ​digital​ ​assets 1.2.​ ​The​ ​KyberNetwork 2.​ ​KyberNetwork’s​ ​Design 2.1.​ ​Actors​ ​in​ ​the​ ​KyberNetwork 2.2.​ ​Dynamic​ ​Reserve​ ​Pool 2.3.​ ​Main​ ​System​ ​Components 2.4.​ ​KyberNetwork​ ​APIs 2.4.1.​ ​User​ ​API 2.4.2.​ ​Reserve​ ​Contributor​ ​API 2.4.3.​ ​Reserve​ ​Manager​ ​API 2.4.4.​ ​KyberNetwork​ ​Operator​ ​API 2.5.​ ​Support​ ​trustless​ ​trading​ ​cross-chain 3.​ ​System​ ​Properties 3.1.​ ​Trustless​ ​and​ ​secure 3.2.​ ​Instant​ ​trade 3.3.​ ​On-chain​ ​exchange 3.4.​ ​Compatibility 3.5.​ ​Comparison​ ​to​ ​existing​ ​systems 4.​ ​Applications 4.1.​ ​Instant​ ​and​ ​secure​ ​exchange 4.2.​ ​Generic​ ​payment​ ​APIs​ ​with​ ​any​ ​token 4.3.​ ​Trusted​ ​on-chain​ ​source​ ​for​ ​rate​ ​quotes 4.4.​ ​Mitigate​ ​the​ ​risks​ ​of​ ​price​ ​fluctuations 4.5.​ ​Forwards 4.6.​ ​Options 5.​ ​Road​ ​map 5.1.​ ​Phase​ ​0:​ ​Testnet​ ​deployment 5.2.​ ​Phase​ ​1:​ ​Basic​ ​mainnet​ ​deployment 5.3.​ ​Phase​ ​2:​ ​Supporting​ ​arbitrary​ ​pairs​ ​of​ ​tokens 5.4.​ ​Phase​ ​3:​ ​Trading​ ​advanced​ ​financial​ ​instruments 5.5.​ ​Phase​ ​4:​ ​Support​ ​cross-chain​ ​trades 2

6.​ ​Crowdsale​ ​and​ ​the​ ​KyberNetwork​ ​Crystal 6.1.​ ​Use​ ​of​ ​tokens 7.​ ​Acknowledgement 8.​ ​The​ ​team 8.1.​ ​Core​ ​members 8.2.​ ​Advisors 3

1.​ ​Introduction Emerging cryptocurrencies such as Bitcoin, Ethereum and others have been gaining tractions of late because they allow users to transact, manage their digital assets in a decentralized and trustless model without relying on a third party. More interestingly, Ethereum network, with its turing complete scripting language and trustless smart contracts, makes its easier for people to issue and digitalize their own crypto tokens which either represents some real-world asset (e.g. Digix Gold token) or has values in some platform (GolemNetwork token, Gnosis token, Augur token and so on). To date, the total market capitalization of the most popular cryptocurrency assets is 72 Billion USD1. This total market cap has tripled in the last 5 months and is still growing. 1.1.​ ​Motivation 1.1.1.​ ​Risk​ ​of​ ​centralization As the Blockchain market grows and more crypto assets are being introduced, the need to convert and exchange between crypto tokens is ever increasing. The trade volume between, for example, ETH and Bitcoin is worth hundreds of million of dollars per day on major exchanges. The total trade volume between ETH and other crypto tokens on its network, most of which are less than 2 years-old, is also in the order of millions of dollars. However, despite the decentralized and trustless natures of cryptocurrencies and crypto tokens, most of the trades happening on centralized exchanges are vulnerable to internal fraud and external hacking. This is an ongoing concern and a number of hacking incidents has been reported at various exchanges2​ ​affecting​ ​thousands​ ​of​ ​users​ ​and​ ​loss​ ​of​ ​hundreds​ ​of​ ​million​ ​of​ ​dollars. 1.1.2.​ ​Lack​ ​of​ ​instant​ ​exchanges Existing exchanges, including centralized and decentralized ones, often require user to wait for several​ ​minutes​ ​before​ ​allowing​ ​them​ ​to​ ​withdraw​ ​their​ ​funds. 1.1.3.​ ​Problem​ ​of​ ​existing​ ​decentralized​ ​exchanges The quests to build decentralized exchanges have been initiated by several parties on the Ethereum network3. Although these parties build decentralized and trustless exchanges, they are still vulnerable to external manipulation since there is a delay when an order is created and when​ ​it​ ​is​ ​accepted​ ​in​ ​a​ ​block​ ​(read​ ​more​ ​here​). 1 ​ ​https://coinmarketcap.com/charts/ 2 ​ ​For​ ​example,​ ​MtGox​,​ ​Bitfinex​,​ ​Shapeshift​. 3 ​ ​See​ 0​ xProject​,​ ​OasisIndex​​ ​and​​ ​EtherDelta​. 4

There are other possible reasons that existing decentralized exchanges are not as popular as expected despite having better security features. These exchanges keep an orderbook of users on the chain. As a result, adjustment or cancellation of bid orders can be expensive to regular users. Repeated revisions of orders will compound the issues as the cost will escalate until a match​ ​between​ ​buy​ ​and​ ​sell​ ​order​ ​is​ ​found. Some exchanges4 hope to resolve this issue by making the price discovery and negotiation process done offline via intermediate parties. A trade is done on-chain only after the two parties have agreed on the rate. This raises the issues of trust in the role of the intermediate party in finding the best counterparty for the trade. We also note that no-fees orders are susceptible to adversarial​ ​sybil​ ​or​ ​denial-of-service​ ​attacks. 1.1.4.​ ​The​ ​problem​ ​of​ ​having​ ​many​ ​digital​ ​assets As the number of ICOs increases, so does the introduction of new crypto tokens. It is logical to assume that investors will acquire a variety of desired crypto tokens as part of their investment strategy. The convertibility of one crypto token to another represents a new challenge for both investors and operators alike. For example, it may be a challenge for any party to allow an already​ ​deployed​ ​contract​ ​to​ ​accept​ ​new​ ​crypto​ ​tokens​ ​as​ ​a​ ​form​ ​of​ ​payment. It also introduces more room for implementation bugs and security flaws. As an example, recently, in the DAO Token ICO, there was ​a major bug that distributed more tokens to SNGLS contributors than to ETH contributors, although they contributed the same amount. Thus, there is a need to simplify the payment procedure for both token holders, merchants and users in the network. 1.2.​ ​The​ ​KyberNetwork We introduce KyberNetwork, an on-chain decentralized exchange providing several useful applications, including building a practical exchange and providing payment APIs for merchants and users to instantly convert tokens effortlessly and “trustlessly”. There is no orderbook. Users will know the conversion rate before sending the transaction and receive the corresponding amount. Users don’t pay any extra fees (other than the gas fees for the transaction). KyberNetwork​ ​benefits​ ​through​ ​pricing​ ​a​ ​reasonable​ ​spread​ ​in​ ​the​ ​conversion​ ​rate. Our users can also send their existing token A, by converting to a different type of token B and sending it to another user, who only accepts payment in B all in one transaction. More interestingly, KyberNetwork introduces a new standard contract wallet to allow existing contracts, which only accepts few tokens, to receive payments from any future tokens without 4 ​ ​Swap.tech​​ ​and​ 0 ​ xproject 5

any modification to the contract code. This allows contracts or merchants to access to a wider class​ ​of​ ​users,​ ​receives​ ​payments​ ​and​ ​contributions​ ​in​ ​any​ ​tokens​ ​that​ ​KyberNetwork​ ​supports. KyberNetwork’s​ ​design​ ​has​ ​several​ ​novel​ ​constructions​ ​to​ ​support​ ​all​ ​these​ ​applications. ● Instead of maintaining a global order book, we maintain a reserve warehouse which holds an appropriate amount of crypto tokens for purposes of maintaining exchange liquidity. The reserve is directly controlled by the Kyber contract, and the contract has a conversion rate for each exchange pair of tokens by fetching from all the reserves. The rates are frequently updated by the reserve managers, and Kyber contract will select the best rate for the users. When a request to convert from token A to token B arrives, the Kyber contract checks if the correct amount of token A has been credited to the contract, then sends the corresponding amount of token B to the sender’s specified address. The amount​ ​of​ ​token​ ​A,​ ​after​ ​the​ ​fees,​ ​is​ ​credited​ ​to​ ​the​ ​reserve​ ​that​ ​provides​ ​the​ ​token​ ​B. ● We introduce a new standard contract wallet to enable some of our interesting applications. Specifically, our new standard contract wallet allows the Kyber contract to send a user’s newly converted tokens to his/ her destination address on the user’s behalf. The destination address will receive the converted tokens as if the tokens were sent​ ​from​ ​the​ ​sender,​ ​not​ ​the​ ​Kyber​ ​contract. ● Our long-term plan also includes employing future features of the EVM language to build an efficient ZCash-Relay on Ethereum. A ZCash-Relay on Ethereum will allow us to support cross-chain trades between ETH and ZEC. We also leverage future platforms like​ ​Polkadot​ ​and​ ​Cosmos​ ​to​ ​enable​ ​more​ ​cross-chain​ ​trading​ ​and​ ​payments. ● The Kyber contract is designed with extensibility-focus which has well modularized components. Specifically, we allow dynamically adding any new tokens or delisting existing​ ​tokens.​ ​Thus,​ ​we​ ​are​ ​able​ ​to​ ​work​ ​with​ ​any​ ​tokens​ ​or​ ​digital​ ​assets​ ​in​ ​the​ ​future. 2.​ ​KyberNetwork’s​ ​Design 2.1.​ ​Actors​ ​in​ ​the​ ​KyberNetwork There​ ​are​ ​5​ ​roles​ ​for​ ​the​ ​actors​ ​in​ ​the​ ​network: 1. Users who send and receive token5 to and from the network. Users in KyberNetwork includes​ ​individual​ ​users,​ ​smart​ ​contract​ ​accounts​ ​and​ ​merchants. 2. A reserve entity(ies) provides liquidity to the platform. This can be our own reserve or other third party reserves that are registered by other market makers. Reserves can also be classified into public and private reserves which do and do not take contributions from the​ ​public. 3. Reserve contributors who provide capital to the reserve entity and share the platform profit. This actor only exists in public reserves which accept contributions from public to build​ ​up​ ​the​ ​reserve. 5 ​ ​For​ ​the​ ​rest​ ​of​ ​this​ ​paper​ ​a​ ​token​ ​also​ ​refers​ ​to​ ​the​ ​Ether​ ​currency. 6

4. Reserve manager who maintains the reserve, determines exchange rates and feeds the rates​ ​to​ ​the​ ​KyberNetwork. 5. KyberNetwork operator who is responsible to add and remove reserve entities, list/delist pairs of tokens in the network. Initially the Kyber team will act as the KyberNetwork operators to bootstrap the platform in the early phases. Later on, a proper decentralized governance​ ​will​ ​be​ ​set​ ​up​ ​to​ ​take​ ​over​ ​the​ ​task. Each of the actors interacts with the smart contract independently in a different way. The users send and receive tokens within a single transaction, without waiting for any response from the reserve or the KyberNetwork operator. The KyberNetwork operator is responsible for adding and removing reserves, while the reserve manager determines and feeds the exchange rates to the contract for a fixed period (several seconds basis). The main contract relies on the reserve entity​ ​to​ ​guarantee​ ​high​ ​liquidity. The​ ​diagram​ ​below​ ​illustrates​ ​the​ ​interaction​ ​of​ ​each​ ​of​ ​the​ ​actors. 2.2.​ ​Dynamic​ ​Reserve​ ​Pool KyberNetwork guarantees high liquidity by leveraging the existing reserves in the network. Different reserves are directly managed by different reserve managers, which may and may not be associated to KyberNetwork operator. KyberNetwork allows multiple reserves to co-exist to enable better prices (by eliminating monopoly of reserve), guarantee better liquidity (by utilising 7

other sources). Furthermore, allowing different people, apart from KyberNetwork operator, to manage their own reserves permits KyberNetwork to support low-trading-volume tokens by off-loading the management efforts of those tokens to corresponding reserve managers. Thus, different parties who wish to take the risk of trading/ converting low-trading-volume tokens can create their own reserve of those tokens and register with KyberNetwork. Note that KyberNetwork does not hold any funds of the reserves that register with it. Their funds are stored​ ​on​ ​their​ ​reserve​ ​contracts​ ​which​ ​will​ ​follow​ ​KyberNetwork​ ​ground​ ​principles. When a trade/ conversion request arrives, KyberNetwork will fetch the conversion rates from all reserves that can process the request. KyberNetwork then selects the best rates and executes the request. We guarantee that both the reserves and the users are safe, namely we do not keep​ ​any​ ​party’s​ ​funds​ ​and​ ​all​ ​transactions​ ​are​ ​atomic. We note that when we launch KyberNetwork, it is likely to have only a single reserve provided by us in the network. This reserve will be the main source of liquidity for the system before other reserves​ ​are​ ​registered. Why other reserves should join KyberNetwork? ​KyberNetwork creates a platform for reserve managers to monetize their otherwise idle assets. By serving trade requests from users, reserves earn profit from the spread, which they can decide on their own. Of course the reserves can always do the trading without joining KyberNetwork, however they will get higher volume due to network effects in KyberNetwork. We will bring more users to KyberNetwork by having​ ​collaborations​ ​with​ ​wallet​ ​providers​ ​and​ ​other​ ​token​ ​projects. In addition, KyberNetwork also provides a reserve dashboard software to help reserve managers manage their reserve portfolio. The reserve dashboard will include standard and popular trading algorithms/ strategies to allow reserve managers to automatically make prices and rebalance their portfolio. Our reserve dashboard is flexible enough that reserve managers can​ ​always​ ​implement​ ​and​ ​deploy​ ​their​ ​own​ ​strategies​ ​when​ ​and​ ​where​ ​they​ ​see​ ​fit. How to keep the reserves safe? ​The security of reserves becomes a major concern in KyberNetwork, especially for public reserves that take contributions from other members in the network. One of the primary concerns is that a bad/unethical reserve manager may quote and trade​ ​bad​ ​prices​ ​to​ ​him/herself​ ​to​ ​drain​ ​all​ ​coins​ ​from​ ​the​ ​reserve. Let us categorize the reserves into two types: (1) private reserves which do not accept contributions and (2) ​public reserves which take external contributions and share profits with contributors. Whilst still a valid concern, if reserve managers of private reserves follow good security practices, the risk exposure of private reserves can be confined to an acceptable range, especially since the reserves are handled locally and other parties cannot interfere without permission. On the other hand, public reserves are subject to greater risk exposure due to its open nature. To mitigate the security risks of public reserves, we will employ a transparent fund management model, for example MelonFund (developed by MelonPort), so that contributors of the reserve can track all trading activities done by reserve managers. On top of that, we also plan to introduce restrictions to protect open reserves. For example, the funds of the reserves 8

can only be transferred to predefined addresses in the contracts, such as the reserve contract itself, and other exchanges that the reserves interact with. Hence, the risk of unwarranted extraction of funds out of the system is removed. Also, to prevent reserve managers from deliberately setting up false and unreasonable exchange rates, e.g. one million Golem Network Token (GNT) per Ether when the spot rate is only five hundred GNT to one Ether, just so that the manager can buy GNTs at a cheap price, we employ both on-chain mechanisms (e.g., prevent unreasonable changes in price without special authorization) and by off-chain mechanisms. For example, a background monitor that will halt transactions when the system detects dubious activities that undermine the integrity of the network can watch and flag out suspicious​ ​behaviours​ ​from​ ​any​ ​reserve​ ​manager​ ​in​ ​the​ ​network. 2.3.​ ​Main​ ​System​ ​Components KyberNetwork​ ​consists​ ​of​ ​the​ ​following​ ​major​ ​components​ ​in​ ​its​ ​system. ● Smart contracts: KyberNetwork contains several contracts, including the main contract which serves as the main entrance to the system for users and reserve managers. We also have different contracts to maintain the reserves, and a contract wallet which provides​ ​convenient​ ​interface​ ​to​ ​all​ ​features​ ​that​ ​Kyber​ ​supports. ● User’s wallet: Wallet apps with friendly interfaces to support users. Integrations with existing wallet apps like Status, Token, Metamask and so on will help improve the adoption​ ​of​ ​KyberNetwork. ● Reserve manager portal: aids the management of the reserve by displaying their performance, network stats, supporting different strategies and algorithms to make prices/ rebalance. Reserve managers interact with the network (or the Kyber contract) via​ ​this​ ​portal. ● Operator dashboard: Helps KyberNetwork operator manage the entire system. Operator can​ ​add​ ​and​ ​remove​ ​new​ ​reserves,​ ​change​ ​network​ ​parameters​ ​via​ ​this​ ​dashboard. A minimum-viable-product has been released in August 2017. The readers can find more details in​ ​our​ ​release​ ​blog​ ​post​ 6​ . 2.4.​ ​KyberNetwork​ ​APIs KyberNetwork​ ​supports​ ​different​ ​API​ ​commands​ ​for​ ​users,​ ​reserve​ ​and​ ​reserve​ ​contributors. 2.4.1.​ ​User​ ​API User​ ​API​ ​can​ ​be​ ​called​ ​by​ ​any​ ​Ethereum​ ​account,​ ​including​ ​normal​ ​account​ ​and​ ​contract​ ​ones. Transfer(​ ​amount,​ ​source​ ​tokens,​ ​destination​ ​token​ ​name,​ ​destination​ ​address) Transfer function converts ​amount of source tokens (token A) to destination tokens (token B) and​ ​sends​ ​type​ ​B​ ​tokens​ ​to​ ​destination​ ​address.​ ​For​ ​example,​ ​users​ ​can​ ​call 6 ​ ​https://blog.kyber.network/kybernetwork-mvp-release-e8440a79346f 9

​ ​Transfer(​ ​100,​ ​“DGD”,​ ​“Melon”,​ ​“0xb794f5ea0ba39494ce839613fffba74279579268”​) to convert 100 DigixDao tokens to Melonport tokens and transfer all converted Melonport tokens to​ ​“0xb794f5ea0ba39494ce839613fffba74279579268”. GetExchangeRate(​ ​token​ ​A,​ ​token​ ​B) Returns the conversion rate between token A and token B. In the future we can support different exchange​ ​rates​ ​for​ ​different​ ​trade​ ​volumes. 2.4.2.​ ​Reserve​ ​Contributor​ ​API Reserve Contributor APIs can be called by any account in the Ethereum network, though some API only works if the account already contributed. There will be two different reserve types in KyberNetwork: private ones which do not take public contributions and public ones which allow others to contribute funds. The APIs for public reserves highly resemble ones from ​MelonFund (decentralized​ ​hedge​ ​fund​ ​platform​ ​built​ ​by​ ​MelonPort).​ ​Here​ ​we​ ​list​ ​the​ ​main​ ​ones. ContributeReserve(token​ ​type,​ ​amount) Contribute some amount of tokens of a certain token type to the reserve. For every contribution, the contributor will receive some amount of reserve tokens/ shares to represent their contribution to the platform. We refer the readers to Melonport’s greenpaper for more technical details. WithdrawProfits() Profits are distributed proportionally to the contributions of the contributors. The exact formula to distribute​ ​the​ ​platform​ ​profits​ ​will​ ​depend​ ​on​ ​the​ ​implementation​ ​of​ ​the​ ​reserve. WithdrawContribution(KNC​ ​amount,​ ​token​ ​type) An existing contributor can withdraw their contribution from the reserve. The contributor can specify in which token type that he wishes to receive for his withdrawn contribution, we do the conversion​ ​in​ ​the​ ​background. 2.4.3.​ ​Reserve​ ​Manager​ ​API SetRate(​ ​token​ ​A​ ​,​ ​token​ ​B,​ ​rate) To set a conversion rate between an existing pair of token A and token B. In the real deployment, this API will be replaced by a different API which updates the rates of all existing pairs​ ​in​ ​one​ ​transaction.​ ​The​ ​purpose​ ​of​ ​batch-update​ ​is​ ​mainly​ ​to​ ​reduce​ ​the​ ​gas​ ​cost. 2.4.4.​ ​KyberNetwork​ ​Operator​ ​API ListPair​ ​(token​ ​A,​ ​token​ ​B,​ ​initial​ ​rate) To​ ​introduce​ ​a​ ​new​ ​pair​ ​of​ ​tokens​ ​that​ ​KyberNetwork​ ​supports. 10

DelistPair​ ​(token​ ​A,​ ​token​ ​B) To​ ​stop​ ​accepting​ ​trade​ ​between​ ​a​ ​pair​ ​of​ ​tokens. AddReserve​ ​(reserveAddress) Add​ ​a​ ​new​ ​reserve​ ​to​ ​the​ ​network.​ ​The​ ​reserve​ ​is​ ​managed​ ​by​ ​its​ ​own​ ​manager. RemoveReserve​ ​(reserveAddress) Remove an existing reserve from KyberNetwork. The removal is due to low liquidity, bad price and​ ​other​ ​reasons. 2.5.​ ​Support​ ​trustless​ ​trading​ ​cross-chain Chain relays, e.g. BTCRlay, enables communication between different blockchains. The launches of protocols like Polkadot and Cosmos will make cross-chain interactions even easier. KyberNetwork will leverage these technologies to allow Ethereum accounts to receive payments from​ ​different​ ​cryptocurrencies. 3.​ ​System​ ​Properties 3.1.​ ​Trustless​ ​and​ ​secure The KyberNetwork operator does not hold the tokens of the users. Hence, by design, user’s tokens are secured from theft losses. Users need not trust the intentions of the reserve entity and the KNC token holders, as the integrity of the operator is enforced/ensured by the smart contract. 3.2.​ ​Instant​ ​trade An exchange or convert request is executed immediately within a single transaction. Users get their exchanged token at the exact moment they transferred their original token. No deposit or confirmation or waiting time is needed. This efficient and user friendly feature distinguishes KyberNetwork​ ​from​ ​most​ ​other​ ​existing​ ​and​ ​future​ ​exchanges. 3.3.​ ​On-chain​ ​exchange The exchange runs on chain and is accessible for all accounts, including normal accounts and smart contracts. That allows smart contracts to directly interact with the exchange without a third party intervention to receive funds/ payments from different tokens that they do not support 11

originally. This feature enables usKyberNetwork to be an on-chain proxy payment platform for all​ ​accounts,​ ​including​ ​normal​ ​accounts​ ​and​ ​smart​ ​contracts. 3.4.​ ​Compatibility KyberNetwork does not require any modification in the underlying protocol of Ethereum and existing smart contracts to function. Our payment API can communicate with existing contracts without​ ​any​ ​change​ ​on​ ​their​ ​side. That said, we also introduce a new contract wallet that holds all user Ether and tokens. The wallet allows the user to pay with token A to a contract that expects token B, where the conversion from A to B is seamlessly done by the KyberNetwork. The receiver will receive the payment​ ​as​ ​if​ ​it​ ​was​ ​sent​ ​by​ ​the​ ​original​ ​user. 3.5.​ ​Comparison​ ​to​ ​existing​ ​systems We compare KyberNetwork to existing systems in the table below. We left out Bancor intentionally as they claim (from our private conversation) to be a platform that focus on community​ ​tokens,​ ​rather​ ​than​ ​general​ ​purpose​ ​exchange. Exchange Trading Trustless Instant On-chain Guaranteed SecureAgainst Cost​ 7​ Trades Liquidity Attacks Kraken/Poloniex Low No No No Yes No Shapeshift Low No Yes No Yes No Coinbase Low No Yes No Yes No EtherDelta High Yes No Yes No Yes Oasis​ ​Index Swap.tech Low Somewh- No Hybrid No Not​ ​sure9 0xProject Low at8 KyberNetwork Low Yes Yes Yes Yes Yes 7 ​ ​Cost​ ​to​ ​execute​ ​a​ ​trade,​ ​apart​ ​from​ ​the​ ​trading​ ​fees. 8 ​ ​Users​ ​need​ ​to​ ​trust​ ​the​ ​relays​ ​to​ ​match​ ​them​ ​the​ ​best​ ​counterparties 9 ​ ​Attackers​ ​can​ ​create​ ​fake​ ​orders​ ​without​ ​any​ ​cost.​ ​No​ ​guarantee​ ​that​ ​a​ ​trade​ ​can​ ​be​ ​settled. 12

4.​ ​Applications 4.1.​ ​Instant​ ​and​ ​secure​ ​exchange First and foremost, KyberNetwork is an exchange. Unlike most exchanges, however, KyberNetwork performs trade requests instantly. Moreover, KyberNetwork does not hold users’ tokens,​ ​thus​ ​any​ ​theft​ ​or​ ​loss​ ​of​ ​tokens​ ​is​ ​prevented​ ​by​ ​design. This contrasts sharply to most exchanges where confirmation time of several minutes is typically needed. Any malfunction during that period could potentially result in inconvenience or in the worst​ ​case​ ​scenario,​ ​loss​ ​of​ ​funds. 4.2.​ ​Generic​ ​payment​ ​APIs​ ​with​ ​any​ ​token Conducting an exchange over a smart contract allows user to pay for any service or product with any crypto token they prefer. The contract will provide instant conversion to Ether and securely pay on behalf of the user to any contract he wishes. The figure below describes how a user could participate in an ICO that accepts only Ether with any token. The entire process occurs within a single transaction, and the KyberNetwork never has a possession on the user tokens​ ​(neither​ ​token​ ​A​ ​nor​ ​token​ ​B). 4.3.​ ​Trusted​ ​on-chain​ ​source​ ​for​ ​rate​ ​quotes KyberNetwork exchange rates are visible to other smart contracts. Hence, it enables the implementation of advanced financial instruments such as swap contracts. The quotes provided by KyberNetwork are secure as they reflect the real rates which are being used to trade between​ ​pairs​ ​of​ ​tokens. 13

4.4.​ ​Mitigate​ ​the​ ​risks​ ​of​ ​price​ ​fluctuations Due to the illiquidity of crypto assets, the exchange rates often seem too volatile due to irregular demand and supply. This issue is aggravated further due to lack of parties that are willing to warehouse crypto-assets. The lack of options means now that it is almost impossible for users of crypto assets to hedge themselves for future requirements. The KyberNetwork will be addressing this challenge by introducing derivatives in the forms of forwards and options to provide​ ​more​ ​alternatives​ ​to​ ​users. 4.5.​ ​Forwards A forward is a contract whereby parties agree to trade an asset at a later date at a price specified in the present. One of the common problems as ICOs become mainstream is the need for some users to convert between tokens, such as from Melon to ETH, in preparation to participate in an upcoming ICO. The user could either acquire ETH at current market rate or commit to a forward contract to negate the risk of the price fluctuations in the ETH as an viable alternative. 4.6.​ ​Options Options contracts allow users to hedge against adverse price movement for a fee called premium. A call option gives the owner of the contract the right to purchase the crypto asset at an agreed price. A put option is an opposite. The premium is calculated using the implied volatility​ ​of​ ​the​ ​underlying​ ​crypto​ ​asset. The user of crypto assets that need to prepare for a future purchase or sale commitments can pay a premium to buy a call or put option. As an example, holders of iced tokens are able to write​ ​call​ ​options​ ​to​ ​earn​ ​premiums​ ​while​ ​forgoing​ ​the​ ​upside​ ​of​ ​the​ ​price. 5.​ ​Road​ ​map The​ ​road​ ​map​ ​of​ ​KyberNetwork​ ​includes​ ​several​ ​phases. 5.1.​ ​Phase​ ​0:​ ​Testnet​ ​deployment Est.​ ​delivery:​ ​August​ ​2017 Develop an MVP version of our platform, including the KyberNetwork wallet, the main KyberNetwork contract and our reserve dashboard. The purpose of this phase is to create a basic and functional version of KyberNetwork with all the main functionalities and applications. The MVP will be released publicly, and the related contracts will be deployed and tested on the Ethereum​ ​testnet. 14

5.2.​ ​Phase​ ​1:​ ​Basic​ ​mainnet​ ​deployment Est.​ ​delivery:​ ​Q1​ ​2018 We deploy the first version of KyberNetwork on the mainnet. We start off with supporting trades and proxy payments between any tokens to and from Ether. It is likely that our reserve will be the the main one that serves all the trades, though we plan to partner with big token holders and other market makers to introduce their reserve in KyberNetwork. The tokens that we support will be​ ​the​ ​popular​ ​tokens​ ​that​ ​have​ ​high​ ​demand​ ​and​ ​high​ ​trading​ ​volumes​ ​in​ ​the​ ​market. We will also partner with wallet providers like MyEtherWallet, Status, Jaxx and others to implement the core features of KyberNetwork. Since most users stay with their favourite wallet, bringing​ ​our​ ​features​ ​to​ ​the​ ​wallets​ ​is​ ​the​ ​best​ ​way​ ​to​ ​increase​ ​the​ ​ ​adoption​ ​of​ ​KyberNetwork. 5.3.​ ​Phase​ ​2:​ ​Supporting​ ​arbitrary​ ​pairs​ ​of​ ​tokens Est.​ ​delivery:​ ​Q2​ ​2018 This phase can be easily achieved following the smooth implementation of phase 1. By then, we expect to have more reserves (i.e. market makers) to join KyberNetwork. The number of supporting​ ​tokens​ ​will​ ​increase​ ​as​ ​we​ ​can​ ​get​ ​more​ ​reserves​ ​in​ ​our​ ​platform. KyberNetwork will also work with other strategic partners to build APIs to allow users in their platforms to efficiently withdraw tokens/ shared fees in prefered tokens. For example, many platforms, projects are employing the fees sharing model in which token holders share all the platform fees (which may be spread in many tokens) collected from platform users. Token holders in these platforms may get their shared fees in, for example, ETH seamlessly via KyberNetwork​ ​if​ ​these​ ​platforms​ ​use​ ​our​ ​related​ ​APIs. 5.4.​ ​Phase​ ​3:​ ​Trading​ ​advanced​ ​financial​ ​instruments Est.​ ​delivery:​ ​Q4​ ​2018 Once our development and operations stabilizes, we will deploy phase 3 of KyberNetwork, in which​ ​we​ ​support​ ​trading​ ​advanced​ ​financial​ ​instruments​ ​as​ ​discussed​ ​in​ ​Section​ ​4. We plan to work with decentralized hedge fund platforms (e.g. provided by Melonport) that allow people to invest in trustless hedge fund and get the profit share from efficient fund managements. Our team needs to discuss, exchange and build APIs between the related platforms to enable us to do what we aim to do in a secure way. Similarly, collaborations with ICOs​ ​projects​ ​that​ ​have​ ​vesting​ ​schemes​ ​for​ ​their​ ​founders,​ ​advisors​ ​are​ ​also​ ​important. 5.5.​ ​Phase​ ​4:​ ​Support​ ​cross-chain​ ​trades Est.​ ​delivery:​ ​End​ ​2018/​ ​Early​ ​2019 The deployment in this phase allows users to trade between Ether/ tokens to Bitcoin, ZCash, ETC and so on. There are two ways to enable this goal: using chain relays (e.g. BTCRelay and ZecRelay) or using interchain communication protocols (e.g. Cosmos, Polkadot). We will watch 15

the development of these protocols and relays closely to decide which solution will be employed in​ ​KyberNetwork. 6.​ ​Crowdsale​ ​and​ ​the​ ​KyberNetwork​ ​Crystal A fixed number of KyberNetwork Crystal tokens (KNC) will be distributed to the public in exchange for Ether contribution. The details of how many KNC are distributed, and how the sale is​ ​conducted​ ​will​ ​be​ ​publicly​ ​available​ ​in​ ​our​ ​blog​ ​posts​ ​and​ ​website. 6.1.​ ​Use​ ​of​ ​tokens KyberNetwork Crystal (KNC) tokens are required for reserves to participate in the network and to​ ​reward​ ​various​ ​parties​ ​who​ ​will​ ​help​ ​generate​ ​more​ ​trading​ ​activities​ ​in​ ​the​ ​platform. KyberNetwork will rely on various partners, including both software and hardware wallets, blockchain explorers, and on-chain smart contracts to direct users to the platform. These partners​ ​will​ ​be​ ​paid​ ​in​ ​KNC​ ​for​ ​every​ ​trade​ ​that​ ​they​ ​introduce​ ​to​ ​KyberNetwork. Before operating, KyberNetwork reserves need to pre-purchase and store KNC tokens. In every trade, a small fraction (exact numbers are TBD) of the trade volume will be paid by the reserve to KyberNetwork platform in KNC. This small fee represents the reserve's payment in return for the right to be able to operate and earn profits from trading activities in KyberNetwork. The collected KNC tokens from the fees, after paying for the operation expenses and to the supporting partners, will be ​burned​, i.e. taken out of circulation. The burning of tokens could potentially increase the appreciation of the remaining KNC tokens as the total supply in circulation reduces. In order to determine the network fees, the conversion rate between KNC and ETH will be updated frequently to the Kyber contract by KNC operators, based on the trading​ ​rates​ ​on​ ​various​ ​exchanges. As an example, for a trade volume of 10 ETH with a 0.01% fee, a corresponding 0.001 ETH worth of KNC will be paid by the chosen reserve to KyberNetwork as a fee for the use of the reserve dashboard and access to network users. Suppose the rate of KNC at the trading time is 1 KNC for 0.1 ETH, the reserve needs to pay 0.01 KNC to the Kyber platform. The wallet/ website that helped the user initiate the trade will get, supposedly, 5% of the fees, or 0.0005 KNC.​ ​The​ ​remaining​ ​95%​ ​of​ ​the​ ​fees,​ ​or​ ​0.0095​ ​KNC​ ​will​ ​be​ ​burned​ ​forever. This approach would increase the demand of existing KNC tokens as the trading volume happening on KyberNetwork increases. The approach also properly rewards all participants who help grow the ecosystem. KNC token holders can easily track the total supply by reading from the​ ​contract,​ ​without​ ​relying​ ​on​ ​any​ ​off-chain​ ​accounting​ ​firm. 16

7.​ ​Acknowledgement We thank our advisors, namely Wong Lee Hong, Vitalik Buterin, Leng Hoe Lon, Prateek Saxena and our friends, namely Tsun Ngai Lee, Stelian Balta, Reto Trinkler for their feedback on the earlier​ ​version​ ​of​ ​this​ ​paper. 8.​ ​The​ ​team 8.1.​ ​Core​ ​members 1. Loi​ ​Luu Loi Luu is a researcher working on cryptocurrencies, smart contract security and ​ nline​, and he distributed consensus algorithms. His research publications are available o is a regular invited speaker at Bitcoin and Ethereum workshops such as DevCon2, EdCon,​ ​Scaling​ ​Bitcoin. Loi believes in the force of the Ethereum and Blockchain technology. Much of his work revolves around this community. He developed Oyente, the first open-source security analyzer for Ethereum smart contracts. Next, he cofounded SmartPool, another open source project which embraces decentralization of mining pools in existing cryptocurrency. He continues to champion decentralisation and trustless properties of the Blockchain with KyberNetwork, taking inspiration and developing value for the community. 2. Yaron​ ​Velner Yaron Velner is a researcher and a co-founder of the SmartPool project. His research is focused on aspects of game theory incentives in blockchain protocols and formal verification of smart contracts. He holds a Phd in computer science from Tel Aviv University. In his Phd thesis he investigated applications of game theory techniques to formal​ ​verification​ ​of​ ​computer​ ​programs​ ​and​ ​systems. Yaron is also an experienced software developer with over 10 years of experience as a senior software engineer and a technical leader at EZchip semi-conductors (recently acquired by Mellanox technologies). At EZchip he was a member in the data structure and​ ​algorithm​ ​team,​ ​which​ ​developed​ ​novel​ ​data​ ​structures​ ​for​ ​IP​ ​routing. 3. Victor​ ​Tran Victor Tran is a senior backend engineer and Linux system administrator. He has experience in developing and building infrastructure for multiple social marketing platforms and advertising networks. He is interested in building high performance multi-platform​ ​applications. 17

Victor co-founded and was CTO of several startups in social marketing. He built and maintained platforms which handled millions of monthly active users. Victor is currently the​ ​lead​ ​engineer​ ​in​ ​the​ ​SmartPool​ ​project. 4. Cuong​ ​Nguyen Cuong is a senior web developer with several years building interesting web applications. He recently spends most of his time on experimenting with various blockchain​ ​platforms​ ​including​ ​Bitcoin,​ ​Ethereum​ ​and​ ​IBM's​ ​Fabric​ ​ledger. 8.2.​ ​Advisors 1. Wong​ ​Lee​ ​Hong Wong Lee Hong career spans across various industries over 3 decades. He has extensive distribution and business development experience in consumer electronic, multimedia, computer gaming, internet and the banking sectors. The second half of his career was spent developing the Internet Banking capability of a major financial institution, venture capital activities in strategic startups and regulatory management role, dealing with banking regulators in Asia in matters relating to banking technology and​ ​operations.​ ​At​ ​present,​ ​he​ ​is​ ​a​ ​Blockchain​ ​enthusiast​ ​and​ ​investor. 2. Leng​ ​Hoe​ ​Lon Leng Hoe Lon co-founded Shentilium with National University of Singapore, with the aim of using the latest data-driven technology to drive business decisions and gain competitive edge. He also co-founded TrackRecord Asia, with the vision that anyone can learn to trade in the financial markets profitably within a professional risk management framework. Prior to this, he held various positions in the financial industry including Deutsche Bank (London and Singapore), JPMorgan (Singapore), ABN Amro (Singapore). He was a Managing Director in Goldman Sachs’ Asia Macro Trading group in HK and Asian FX trader in London. He was also CEO of Tudor Capital Singapore, a global​ ​macro​ ​hedge​ ​fund. 3. Prateek​ ​Saxena Prateek Saxena is a research professor in computer science at National University of Singapore. He works on blockchains and computer security. His research has influenced the design of browser platforms, web standards and app stores widely used today. He has​ ​received​ ​several​ ​premier​ ​awards​ ​such​ ​as​ ​the​ ​MIT​ ​TR35​ ​Asia. 4. Vitalik​ ​Buterin Vitalik is the Founder and Chief Scientist of Ethereum. He is also both the Founder and a writer for Bitcoin Magazine, a venture that marked the beginning of his career in crypto in 2011. He is interested in creating secure, efficient, and trustworthy systems and advises a​ ​number​ ​of​ ​projects​ ​in​ ​the​ ​crypto​ ​space. 18

5. Pandia​ ​Jiang Pandia is the founder of LinkTime and an organizer of several Ethereum workshops in China and world wide. Pandia is an expert at building and managing community, providing crypto-business advisory​ ​in​ ​China. 19