Page 32 - MSDN Magazine, March 2019

BLOCKCHAIN
Verify e-Documents with Smart Contracts in Azure Blockchain
Development Kit
Stefano Tempesta
The introduction of smart contracts in blockchain networks has created a business logic tier that was missing in the early iterations of blockchain. Smart contracts offer the ability to apply conditional logic to transactions before they’re executed. Still, smart contracts can operate only on data that’s stored on the blockchain digital ledger. Business processes, however, rarely run in isolation. They often need data integration with external systems and devices.
For example, processes may include transactions initiated on a distributed ledger that employs data sourced from an external system, service or device. External systems may be required to react to events raised by smart contracts in response to validation logic. This article describes how to automate document sign and verify workflows in SharePoint using the recently released Azure Blockchain Development Kit (aka.ms/bcdevkit) for persisting files’ hash and metadata on a blockchain digital ledger.
Azure Blockchain Development Kit
The release of the Azure Blockchain Development Kit, built on Microsoft’s serverless technology, represents a milestone in the adoption of blockchain technologies in the enterprise space. Thanks to the Blockchain Development Kit, you can now build solutions that seamlessly integrate blockchain with the best of Microsoft and third-party software applications. As mentioned on its release notes, the initial version of the kit prioritizes capabilities related to three key themes: connecting interfaces, integrating data and systems, and deploying smart contracts and blockchain networks.
Connection includes communication channels such as mobile and Web, SMS and voice, as well as IoT devices and even chat bots. Integration with line-of-business applications spans multiple sys- tems, including SharePoint, OneDrive for Business, Dynamics 365, open source, and any API-enabled platforms, as well as legacy protocols like file systems, FTP servers, or SQL databases. The deployment of smart contracts and blockchain networks will help mainstream blockchain technology in enterprise software devel- opment, and introduce governance and DevOps to the blockchain software development practice.
Blockchain Development Kit works in combination with Azure Logic Apps and Flow, which provide a visual design environment for workflows that include more than 200 connectors to Microsoft and third-party systems and services. In concert, they dramatically simplify the development of end-to-end blockchain applications
This article discusses:
• Signing and verification of electronic documents on a blockchain • Integration of SharePoint with Azure Blockchain Workbench
using the Blockchain Development Kit
Technologies discussed:
Blockchain, Smart Contract, Azure Blockchain Development Kit
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