The Linux Foundation’s Hyperledger project is an umbrella initiative under which communities are developing interoperable enterprise-grade, open source permissioned blockchain tools and frameworks. Hyperledger currently has over 170 members, including major software and hardware vendors, system integrators, and blockchain early adopters. Its most active project, the Hyperledger Fabric blockchain framework for developing permissioned blockchains, forms the basis of the blockchain services that a number of major vendors (such as IBM, Oracle, and SAP) have taken to market during 2017.
Hyperledger aims to bring permissioned blockchain technology to the masses
More than a single project, the Linux Foundation’s Hyperledger initiative is the umbrella for multiple, freely available open source and interoperable projects. Its vision is to develop robust standards, tools, and frameworks that help mainstream businesses (across a raft of industries) adopt permissioned blockchain technology, aided by the provision of rich, easy-to-use APIs and application development tools.
Hyperledger Fabric layers business relationships on blockchain networks
Hyperledger Fabric supports a variety of pluggable consensus algorithms and different network node (peer) types, enabling its blockchain networks to be better tuned to particular industry requirements and overarching business relationships. The Hyperledger community is further supporting specific industry use case deployments through best practice and proof-of-concept advice (Finance, and Healthcare now; Supply Chain to come).
Hyperledger Burrow and the inter-ledger divide
The Ethereum-derived Hyperledger Burrow project executes Ethereum smart contracts and has the potential to enable permissioned Hyperledger networks to integrate with Ethereum ones – opening up opportunities for inter-ledger interoperability.
What is Hyperledger?
Hyperledger is not a single project; rather, it was conceived as an umbrella initiative, hosted by the Linux Foundation, for communities to develop interoperable, enterprise-grade, open source permissioned blockchain tools and frameworks. It’s a little like the Apache Foundation’s Hadoop project, with all its related tools, which has acted as a powerhouse of innovation in Big Data software.
Hyperledget was announced in 2015 (initially attracting 17 supporters), and now boasts over ten times that many members including big name software vendors, system integrators, hardware vendors, and blockchain early adopters (such as IBM, SAP, Oracle, R3, ConsenSys, VMware, J.P.Morgan, Accenture, Cap Gemini, Deloitte, EY, Intel, Cisco, NEC, Hitachi, Samsung, Fujitsu, Bosch, Airbus, American Express, Daimler, Wells Fargo, and ABN AMRO). Vendors such as IBM, Oracle and SAP have brought Hyperledger-based blockchain services to market during 2017.
Hyperledger’s goal is to promote the use of permissioned blockchain technologies for business applications across a broad array of industries, as well as contributing code its members are sharing best practices and providing assistance in Proof-of-Concept (PoC) testing across a range of industry specific use cases. To date (reflecting the relative levels of maturity and adoption of blockchain in different sectors, as borne out by spread of projects captured in MWD Advisors’ blockchain project tracker), Hyperledger has published industry-focused use case and PoC guidance in Finance and Healthcare, with Supply Chain / Manufacturing dues to follow.
There are a number of projects live or in incubation under Hyperledger at the moment, providing frameworks and tools tuned to a variety of use case scenarios (reflecting the breadth of interests represented by the Hyperledger community membership).
- Sawtooth (open sourced by Intel in 2015; now an active Hyperledger project) is a modular blockchain platform designed to address the scalability, security, and privacy concerns associated with large and distributed validator populations. It implements Proof-of-Elapsed-Time (PoET) consensus, using Intel’s secure Software Guard Extensions CPU instructions to ensure the safety and randomness (and minimise the resource requirement) of its ‘leader-election lottery’ algorithm (where it’s the leader that proposes the block to be appended to the chain). Pluggable Transaction Families create a tailored smart contract architecture for different domains (such as supply chain tracking, blockchain network performance testing, etc.). Sawtooth demonstrators have been developed in the areas of supply chain traceability, asset settlement, and digital asset exchange.
- Iroha (open sourced by Japanese fintech frim Soramitsu, with contributions from Hitachi, NTT Data, and Colu; now an active Hyperledger project) is a modular C++ blockchain platform based on Hyperledger Fabric, designed to provide component libraries available for other Hyperledger projects to use. It’s focused on mobile application development, and features a Byzantine fault-tolerant consensus algorithm called Sumeragi.
Notable features include:
- Delineation of peer node types on the blockchain network – client nodes submit transaction-invocations to endorsers and broadcast transaction-proposals to orderers; peer nodes commit transactions and maintain the state and a copy of the ledger, execute the chaincode logic and interface with applications (additionally peers can be endorsing peers, able to endorse transactions before they’re committed); and orderer nodes deliver endorsed transactions to peers on the network to ensure the consistency of the blockchain.
- Modular consensus algorithms that don’t rely on expensive ‘mining’ and cryptocurrences, pluggable for different use case scenarios.
- Channels that address privacy concerns by isolating ledgers and providing a mechanism for sharing confidential information without resorting to network encryption – so not every party on a Hyperledger Fabric blockchain network needs to be aware of other parties or their transactions.
- CouchDB as a ‘world state’ database (previously only LevelDB was available) which, as a JSON document store, enables rich queries to be run when chaincode values are modelled as JSON data.
- A Bring-Your-Own-MSP model, providing modularity and interoperability across different membership standards and architectures.
- Endorsement policies that instruct a network peer how to determine whether a transaction is properly endorsed (i.e. that an appropriate number of endorsements are present, and that they originate from expected sources).
- Burrow (originally called “eris-db” and initially contributed by Monax in December 2014, co-sponsored by Intel; currently in incubation) is a modular blockchain client that includes a permissioned smart contract interpreter, partially developed to the specification of the Ethereum Virtual Machine (which runs Ethereum smart contracts in a sandboxed environment on each Ethereum node).
- Cello (originating from IBM and co-sponsored by Soramitsu, Huwaei and Intel; currently in incubation) is a toolkit designed to facilitate rapid blockchain deployment to cloud platforms. It provides a multi-tenant chain service on top of a variety of infrastructures, such as bare metal, virtual machine, and container platforms.
- Playground – a web-based tool for developers to model their business network, and deploy to a live blockchain network in which to test it.
- Business network archive – that captures and packages up core business network data (including the business model, transaction logic, and access controls) to deploy to a runtime environment.
- REST API support via a LoopBack connector – which exposes a running blockchain network as a REST API that can be consumed by, and integrated with, client applications and non-blockchain systems-of-record.
Although Composer does offer business-centric abstractions, sample apps, and devops processes, it’s still a pretty technical environment – business users will need to work in tandem with a skilled developer; it’s a long way from being the sort of business user-friendly module might encourage a wave of ‘citizen chaincoders’ (not everything is abstracted yet, either – channels and policy permissioning still need to be performed using a command line interface). Nevertheless, Composer does highlight Hyperledger’s intention to democratise not only processes on the blockchain for end users, but also access to developing the distributed Hyperledger applications that run on it.
- Explorer (initially contributed by IBM, Intel and DTCC; currently in incubation) is designed to create user-friendly web applications on top of Hyperledger Fabric. It can view, invoke, deploy or query a range of information store on the ledger (such as blocks, transactions and associated data, network information, chaincode and transaction families).
As well as the current crop of in-incubation and active projects – each with its own development roadmap as it builds upon its first production release (in the case of Fabric) or works towards general availability – a number of further frameworks and tools are promised as “coming soon” to the Hyperledger stable, including:
- Indy (contributed by the Sovrin Foundation) is due to bring tools, libraries, and reusable components for providing blockchain digital identities that can be used across applications and administrative domains, etc.
- Quilt is intended to provide a level of inter-ledger interoperability via the Interledger Protocol (ILP – designed to transfer payments between distributed ledgers and traditional databases).