This is a proof of concept to demonstrate how Blockchain brings the CSPs on single Blockchain Hyperledger network which enables direct exchange of information with transactions that are immutable and executed based on consensus model using smart contract rules.

This business network defines:

Participants: Home Operator Roaming Partner

Assets: Subscriber Sims

Transactions: discovery authentication updaterate callout overagecheck callend callpay addUser

There are four scenarions covered :

1. Roaming Subscriber Identification A subscriber moves to a new location out of home network. Is discovered by Roaming Partner. discovery transaction is executed. Roaming Partner authenticates Roaming Subscriber as a visitor from Home Operator. authentication transaction is executed. Home Operator register Roaming Subscriber accordingly. updaterate transaction is executed.
2. Roaming Subscriber Billing Now that authorized, Roaming Subscriber uses Roaming Partner network to initiate a call. callout and callend transactions are executed. The charges for network usage are instantaneously recorded between Home Operator and Roaming Partner based on their agreement. callpay transaction is executed.
3. Fraud Identification Addition of a Fraudulent Subscriber is simulated. addUser transaction is executed. Fraudulent Subscriber tries to registered to access the Home Operator network using the same MSISDN of an existing user Authentication step identifies the subscriber and prevent the fraud. authentication transaction is executed.
4. Overage Management A roaming subscriber intiates a call/ Smart contract recognizes that subscriber is potentially reaching overage threshold. callout transaction is executed. Operator notifies the Overage Subscriber of the potential tariff change. overagecheck transaction is executed.

Audience level : Intermediate Developers

If you have an IBM cloud lite account, you can also use the Starter Plan for 30 days to do this pattern.

• Hyperledger Fabric
• Hyperledger Composer

• Blockchain
• Containers
• Cloud

• Install Hyperledger Composer development tools
• Configure and start Hyperledger Fabric network
• Generate the Business Network Archive file
• Deploy the Business Network Archive using Composer Playground
• (Alternative method) Deploy the Business Network Archive on Hyperledger Composer running locally

1. Generate the Business Network Archive (BNA)
2. Deploy the Business Network Archive using Composer Playground
3. Deploy the Business Network Archive on Hyperledger Composer running locally

To check that the structure of the files is valid, you can now generate a Business Network Archive (BNA) file for your business network definition. The BNA file is the deployable unit -- a file that can be deployed to the Composer runtime for execution.

Use the following command to generate the network archive:

npm install

You should see the following output:

Creating Business Network Archive

Looking for package.json of Business Network Definition
	Input directory: /Users/<user-name>/Documents/git-demo/roaming

Found:
	Description: Telecom Roaming Demo
	Name: my-network
	Identifier: [email protected]

Written Business Network Definition Archive file to
	Output file: ./dist/my-network.bna

Command succeeded

The composer archive create command has created a file called my-network.bna in the dist folder.

You can test the business network definition against the embedded runtime that stores the state of 'the blockchain' in-memory in a Node.js process. From your project working directory, open the file test/foodTest.js and run the following command:

npm test

You should see the following output :

> [email protected] test /Users/<user-name>/Documents/demo/roaming
> mocha --recursive

  #composer.food.supply
    ✓ Transfer ProductListing to Importer (67ms)
    ✓ Exempt Check for ProductListing (98ms)
    ✓ Transfer ProductListing to Retailer (95ms)

  3 passing (2s)

Hyperledger Composer is a programming model containing a modeling language, and a set of APIs to quickly define and deploy business networks and applications that allow participants to send transactions that exchange assets. You can experience Hyperledger Composer with the browser-based UI called Hyperledger Composer Playground. Playground is available as a hosted version (no install necessary) or a local install (good for editing and testing sample business networks offline).

Open Composer Playground, by default the Basic Sample Network is imported. If you have previously used Playground, be sure to clear your browser local storage by running localStorage.clear() in your browser Console.

Now import the my-network.bna file and click on Deploy button.

You can also setup Composer Playground locally.

Once the bna is deployed , go to the Test tab

To test your Business Network Definition, first click on the Test tab:

Create CSPs using transaction resetCSP

Model:
resetCSP {
$class (string, optional): The class identifier for this type ,
noneed (string),
transactionId (string, optional): The instance identifier for this type ,
timestamp (string, optional)
}

Example Value:
{
  "$class": "org.gsc.roaming.resetCSP",
  "noneed": "string",
  "transactionId": "string",
  "timestamp": "2017-10-05T07:24:24.743Z"
}

Create Subscribers using transaction resetMSISDN

Model:
resetMSISDN {
$class (string, optional): The class identifier for this type ,
noneed (string),
transactionId (string, optional): The instance identifier for this type ,
timestamp (string, optional)
}

Example Value:
{
  "$class": "org.gsc.roaming.resetMSISDN",
  "noneed": "string",
  "transactionId": "string",
  "timestamp": "2017-10-05T07:24:24.749Z"
}

Scenario 1 :

execute transaction discovery

{
  "$class": "org.gsc.roaming.discovery",
  "asset": "string",
  "rp": "string",
  "location": "string",
  "lat": "string",
  "long": "string",
  "transtype": "string",
  "transactionId": "string",
  "timestamp": "2017-10-05T07:24:24.724Z"
}

execute transaction authentication

{
  "$class": "org.gsc.roaming.authentication",
  "asset": "string",
  "rp": "string",
  "transtype": "string",
  "roaming": "string",
  "flag": "string",
  "transactionId": "string",
  "timestamp": "2017-10-05T07:24:24.657Z"
}

execute transaction updaterate

{
  "$class": "org.gsc.roaming.updaterate",
  "asset": "string",
  "rp": "string",
  "ratetype": "string",
  "transtype": "string",
  "transactionId": "string",
  "timestamp": "2017-10-05T07:24:24.811Z"
}

Similar for other three scenarios.

Please start the local Fabric using the instructions. Now change directory to the dist folder containing my-network.bna file and type:

cd dist
composer runtime install --card PeerAdmin@hlfv1 --businessNetworkName my-network
composer network start --card PeerAdmin@hlfv1 --networkAdmin admin --networkAdminEnrollSecret adminpw --archiveFile food-supply.bna --file networkadmin.card
composer card import --file networkadmin.card

You can verify that the network has been deployed by typing:

composer network ping --card admin@my-network

You should see the the output as follows:

The connection to the network was successfully tested: events
	version: 0.18.1
	participant: org.hyperledger.composer.system.NetworkAdmin#admin
	identity: org.hyperledger.composer.system.Identity#1f95efceac5421ad34d73130c8f16fbc2d29b7dce0c3425afb3b5f077242b1fc

Command succeeded

To create the REST API we need to launch the composer-rest-server and tell it how to connect to our deployed business network. Now launch the server by changing directory to the roaming folder and type:

cd ..
composer-rest-server

Answer the questions posed at startup. These allow the composer-rest-server to connect to Hyperledger Fabric and configure how the REST API is generated.

• Enter admin@my-network as the card name.
• Select never use namespaces when asked whether to use namespaces in the generated API.
• Select No when asked whether to secure the generated API.
• Select Yes when asked whether to enable event publication.
• Select No when asked whether to enable TLS security.

Test REST API

If the composer-rest-server started successfully you should see these two lines are output:

Web server listening at: http://localhost:3000
Browse your REST API at http://localhost:3000/explorer

Open a web browser and navigate to http://localhost:3000/explorer

You should see the LoopBack API Explorer, allowing you to inspect and test the generated REST API. Follow the instructions to test Business Network Definition as mentioned above in the composer section.

• Hyperledger Fabric Docs
• Hyperledger Composer Docs

This code pattern is licensed under the Apache Software License, Version 2. Separate third party code objects invoked within this code pattern are licensed by their respective providers pursuant to their own separate licenses. Contributions are subject to the Developer Certificate of Origin, Version 1.1 (DCO) and the Apache Software License, Version 2.

Apache Software License (ASL) FAQ