Quant Network’s Overledger: Part Four — Features Overledger provides to MAPPs

9 min readApr 5, 2019


Disclaimer: Please note this article was accurate to the best of my knowledge at the time of writing. This information should not be used as a reference source to make any investment decisions (as is the case with all my articles). The Quant team have removed multiple references surrounding tokenomics of the QNT token, including the original tokenomics paper, the Overledger Network for community paper (which you can find an copy on a 3rd party side here ) and archive of removal of medium articles written by Quant surrounding tokenomics can be found here). For clarification around any topics you should seek clarification from other sources rather than rely on any information found in this article.

This is Part Four in the series looking at Quant Network, where we look at some of the additional features Overledger provides to Developers building MAPPs . We look at what a DAPP and a MAPP are, Treaty Contracts which allow Smart Contracts to be used across multiple blockchains even those that don’t support Smart Contracts natively such as Bitcoin. As well as Quant IP connecting the Internet directly to blockchain and Quant Cyber offering additional security functionality with Firewalls, Intrustion Prevention etc and much more.

Part one can be found here and a link to the other parts can be found at the bottom of this article.

What is a DAPP?

As discussed in Part one, an DApp generally consists of a few components:

Front end- Front end is where the user interface is and is what the end user sees to interact with the application. When you browse to twitter.com in a web browser or open the app on your phone that is the front end. This is normally centralised but can also be decentralised by being stored on solutions such as IPFS

API — The front end Connects to the Back end via an API such as Javascript API utilising a library such as Web3.js that provides available options on how to interact with smart contracts

Smart Contracts — Smart Contracts run on Virtual Machines on the blockchain (such as Ethereum Virtual Machine EVM for Ethereum). These provide Interaction with the underlying Blockchain where the transactions / data are stored.

Blockchain — Decentralised network of nodes that is capable of running smart contracts such as Ethereum.

What is a MAPP?

A Mapp consists of the following components:

Front end- This can be easily integrated into existing apps that are running in locations such as Google Play Store, Apple Play Store, Traditional Web Servers or IPFS.

Quant have released an Overledger Software Developer Kit (SDK) which is embedded in the front End and enables apps to define the rules to interact with Overledger and define how to add messages or to read the output of a write to the various blockchains. The SDK is open source and is currently available in Java, Javascript with plans to add Python and Ruby later. As its open source the community can create their own version in their preferred programming language to define how to interact with Overledger.

API—This is Overledger’s (Blockchain Programmable Interface) which stores the rules the Mapps have defined through the SDK and allows interaction with the Overledger Operating system and the connected blockchains.

Treaty Contracts (Optional) — Treaty Contracts are smart contracts that are run off chain for higher performance and provide the ability to run smart contracts across multiple blockchains (even those such as Bitcoin which don’t support smart contracts). I talk in more detail about Treaty contracts later in this article.

Blockchains — Mapp is no longer restricted to a single blockchain and can utilise multiple as well as having the ability to easily migrate to anther if required. Decentralised networks of nodes that doesn’t have to include smart contract capability.

Treaty Contracts

A problem the team identified early on was the limitation of smart contracts to be recognised on multiple blockchains. If a smart contract is executed on Ethereum, why can’t the Hyperledger blockchain see that the contract is in place or has executed? Also why can’t the smart contract include code executed on other blockchains as part of its steps?

To understand more about this space they looked at how traditional contracts are structured. They looked at the principles of law in the UK, EU and internationally to understand how local laws are recognised when dealing in cross-border transactions. The principles in contracts usually contain a clause that refers back to a local legal system or court. In more international matters, countries sign up to conventions or treaties such as the Berne Convention of 1886 for the protection of literary and artistic works.

They want to enable entities to export their transactions that occur on one blockchain to be recognised and executed on other blockchains. The underlying operating system of Overledger will allow the transferability, recognition and execution of smart contracts from one blockchain to another.

What this was showing was our Treaty Contract operational. Ethereum smart contract listening to events on Ripple!!!! As permission less systems, then moving it not only to Hyperledger as a permissions system of record, but also decoding it and displaying a Google map to show the route.

Running smart contracts on platforms like Ethereum are slow though (it has to run the smart contract in an EVM on every node on the network (at one point Ethereum had 25,000 nodes). Ethereum also uses its own programming language Solidity to create the smart contracts, as do many others — Digital Assets DAML, Michelson for Tezos, K Framework for Cardano etc etc. As these are new, finding developers can be extremely difficult. Likewise, if you want to migrate from one blockchain to another, you are going to have to completely rewrite your smart contracts in the new blockchain’s programming language.

What Overledger will allow with Treaty contracts is to use popular programming languages such as Java and create a smart contract in Overledger that interacts with all of the connected blockchains. Even providing Smart contract functionality to blockchains that don’t support them such as Bitcoin. This means that developers don’t have to create all the smart contracts on each blockchain in all the different programming languages but instead just create them in Overledger using languages such as Java that are widely used today. If they need to use a different blockchain then it can be as easy as changing a line of code rather than having to completely rewrite the smart contracts.

Overledger isn’t a blockchain though, so how can it trusted with the smart contract? A Hash of the smart contract is published on any blockchain the MAPP developer requires and when called the smart contract is run its run through a hashing function to check that it matches the Hash value stored on the blockchain, ensuring that it has not been modified.

By running the Smart contract off chain this also increases Scalability enormously. With a blockchain all nodes have to run the smart contract one after another rather than in parallel. Not only do you get the performance benefit of not having to run the code against every single node but you can also run them in parallel to others executing smart contracts.

Giving the Developer Choice and Flexibility

Each Blockchain has their own Strengths and Weaknesses and different capabilities, whether that be transactions per second, features, privacy, security, smart contracts, payments etc. An application can consist of many components which Developers of DAPPS have to choose which one chain offers the best features to cover all of the required components, resulting in tradeoffs. What a MAPP allows the Developer to do is to select the best Blockchain for each specific component rather and link them together. So, for example, part of the application that handles storage of sensitive data could utilise a permissioned blockchain (or multiple), components that handle payments could utilise Ripple or Stellar, components that utilise IOT could use IOTA etc. Resulting in the developer not having to make compromises by choosing just one chain to handle all but being able to achieve its true potential.

This also provides additional features such as not being locked into one chain with the ability to easily migrate and transfer your workload from one chain to another, an essential requirement for Enterprises. As we alluded to with Treaty contracts this also provides a single programming language to integrate with so doesn’t involve rewriting all the code.

In addition of being able to completely migrate from one blockchain to another Quant Network are adding Least Cost Routing to Overledger. What this will do is allow MAPPS to utilise multiple blockchains for a component but choose the one that costs the least in transaction fees at the time. If you had a component running on the Ethereum Blockchain and Cryptokitties was released causing the network to slow to a crawl and gas prices to rise through the roof, least cost routing would automatically utilise a different blockchain such as NEO as an example instead. Or for the Payments component you may utilise not only Ripple or Stellar but also integrate with Non Blockchain services such as SWIFT and this can automatically be selected depending on which method is the cheapest.

An important thing to note is that despite the developer potentially using multiple chains in the back end for the DAPP, the end user can just utilise one blockchain, meaning they don’t have to worry about having all the different Tokens of the connected chains as these are managed by the Developer via easy to integrate wallets. Depending on the APP the end user may not need to hold any of their own currency at all and don’t even realise they are using a blockchain, the wallet is created through the MAPP and handled by the developer. An example of this can be seen below at the QuantX presentation

Internet of Trust

Quant IP

Quant Network are also developing the ability to allow Developers to build MAPPs that integrate directly with the internet as well as blockchain Data. They will enable this via creating a new IP address for Blockchains which they are calling Quant IP which will enable traffic to be routed from an IP connection from the Internet through Overledger to the Blockchains.

An example of this is shown via a distributed search engine that is able to search and retrieve data from multiple blockchains and display them via html directly from the blockchain.

To mark the official launch of the European Commission-supported International Association of Trusted Blockchain Applications — INATBA where 105 organisations representing the full distributed ledger technology (DLT) ecosystem, announced their commitment to a new platform, the International Association of Trusted Blockchain Applications.

Using Overledger, with a single transaction we have written the INATBA hash on to Ethereum, Ripple and Bitcoin.

Launched with a ceremonial digital signing at the European Commission headquarters, INATBA will promote the use of blockchain technology by developing a predictable, transparent and trust-based global framework.

You can search for the INATBA hashes using Quant’s Multichain Search




This will allow Websites to be natively created and served directly from Blockchains, without the need to have, run and maintain web servers, web services, SSL certificates etc and all running in a completely trusted, extremely resilient / tamperproof environment. The implications of this are enormous and more details will be released by the team later on this exciting prospect.

Quant Network have also produced their own blockchain specifically built for large storage to facilitate the storage of Data, MAPPs front End etc as well as easily integrating to other storage solutions such as IPFS, Bittorent, Dropbox etc

Quant Cyber

Given the teams extremely strong Cybersecurity background, they will also be releasing a number of MAPPS as part of Quant Cyber. The first of these will be GoVerify mentioned in Part Three which protects people from impersonation and deception fraud. In addition they are also planning to offer solutions for Identity as a Service, Firewalls, Deep Packet Inspection (DPI) and Intrusion Prevention Systems (IPS) giving additional security controls to use with Blockchains which don’t exist today.

In Part Five I will look at why standards are Important and how Quant is playing an integral role in achieving these international standards involving 53 countries

Part One — Blockchain Fundamentals

Part Two — The Layers Of Overledger

Part Three — Verification and the Tokenisation of data

Part Four — Features Overledger provides to MAPPs (This Article)

Part Five — Creating the Standards for Interoperability

Part Six — The Team behind Overledger and Partners

Part Seven — The QNT Token

Part Eight — Enabling Enterprise Mass Adoption

Value Beyond Speculation — Why Quant has the potential to be an incredible long-term investment

Quant Network Enabling Mass Adoption of Blockchain at a Rapid Pace

Quant Network Partner with SIA, A Game Changer for Mass Blockchain Adoption by Financial Institutions

What is a blockchain operating system and what are the benefits? Introducing Overledger from Quant Network

Wall Street 2.0: How Blockchain will revolutionise Wall Street and a closer look at Quant Network’s Partnership with AX Trading

Large Enterprise Adoption of Blockchain is happening, enabled by Quant Network’s Overledger




DLT Enthusiast and Writer. Interoperability is key for DLT to achieve its true potential. Avalanche $AVAX