Analyze phone call data with Stream Analytics and visualize results in Power BI dashboard
This tutorial teaches how to analyze phone call data using Azure Stream Analytics. The phone call data, generated by a client application, contains some fraudulent calls which will be filtered by the Stream Analytics job.
In this tutorial, you learn how to:
- Generate sample phone call data and send it to Azure Event Hubs
- Create a Stream Analytics job
- Configure job input and output
- Define a query to filter fraudulent calls
- Test and start the job
- Visualize results in Power BI
Before you start, make sure you have the following:
- If you don't have an Azure subscription, create a free account.
- Log in to the Azure portal.
- Download the phone call event generator app TelcoGenerator.zip from the Microsoft Download Center or get the source code from GitHub.
- You will need Power BI account.
Create an Azure Event Hub
Before Stream Analytics can analyze the fraudulent calls data stream, the data needs to be sent to Azure. In this tutorial, you will send data to Azure by using Azure Event Hubs.
Use the following steps to create an Event Hub and send call data to that Event Hub:
Log in to the Azure portal.
Select Create a resource > Internet of Things > Event Hubs.
Fill out the Create Namespace pane with the following values:
Setting Suggested value Description Name myEventHubsNS A unique name to identify the event hub namespace. Subscription <Your subscription> Select an Azure subscription where you want to create the event hub. Resource group MyASADemoRG Select Create New and enter a new resource-group name for your account. Location West US2 Location where the event hub namespace can be deployed.
Use default options on the remaining settings and select Create.
When the namespace has finished deploying, go to All resources and find myEventHubsNS in the list of Azure resources. Select myEventHubsNS to open it.
Next select +Event Hub and enter the Name as MyEventHub or a different name of your choice. Use the default options on the remaining settings and select Create. Then wait for the deployment to succeed.
Grant access to the event hub and get a connection string
Before an application can send data to Azure Event Hubs, the event hub must have a policy that allows appropriate access. The access policy produces a connection string that includes authorization information.
Navigate to the event hub you created in the previous step,MyEventHub. Select Shared access policies under Settings, and then select + Add.
Name the policy MyPolicy and ensure Manage is checked. Then select Create.
Once the policy is created, select to open the policy, and find the Connection string–primary key. Select the blue copy button next to the connection string.
Paste the connection string into a text editor. You need this connection string in the next section.
The connection string looks as follows:
Endpoint=sb://<Your event hub namespace>.servicebus.windows.net/;SharedAccessKeyName=<Your shared access policy name>;SharedAccessKey=<generated key>;EntityPath=<Your event hub name>
Notice that the connection string contains multiple key-value pairs separated with semicolons: Endpoint, SharedAccessKeyName, SharedAccessKey, and EntityPath.
Start the event generator application
Before you start the TelcoGenerator app, you should configure it to send data to the Azure Event Hubs you created earlier.
Extract the contents of TelcoGenerator.zip file.
TelcoGenerator\TelcoGenerator\telcodatagen.exe.configfile in a text editor of your choice (There is more than one .config file, so be sure that you open the right one.)
<appSettings>element in the config file with the following details:
- Set the value of the EventHubName key to the value of the EntityPath in the connection string.
- Set the value of the Microsoft.ServiceBus.ConnectionString key to the connection string without the EntityPath value (don't forget to remove the semicolon that precedes it).
Save the file.
Next open a command window and change to the folder where you unzipped the TelcoGenerator application. Then enter the following command:
telcodatagen.exe 1000 0.2 2
This command takes the following parameters:
- Number of call data records per hour.
- Percentage of fraud probability, which is how often the app should simulate a fraudulent call. The value 0.2 means that about 20% of the call records will look fraudulent.
- Duration in hours, which is the number of hours that the app should run. You can also stop the app any time by ending the process (Ctrl+C) at the command line.
After a few seconds, the app starts displaying phone call records on the screen as it sends them to the event hub. The phone call data contains the following fields:
Record Definition CallrecTime The timestamp for the call start time. SwitchNum The telephone switch used to connect the call. For this example, the switches are strings that represent the country/region of origin (US, China, UK, Germany, or Australia). CallingNum The phone number of the caller. CallingIMSI The International Mobile Subscriber Identity (IMSI). It's a unique identifier of the caller. CalledNum The phone number of the call recipient. CalledIMSI International Mobile Subscriber Identity (IMSI). It's a unique identifier of the call recipient.
Create a Stream Analytics job
Now that you have a stream of call events, you can create a Stream Analytics job that reads data from the event hub.
To create a Stream Analytics job, navigate to the Azure portal.
Select Create a resource > Internet of Things > Stream Analytics job.
Fill out the New Stream Analytics job pane with the following values:
Setting Suggested value Description Job name ASATutorial A unique name to identify the event hub namespace. Subscription <Your subscription> Select an Azure subscription where you want to create the job. Resource group MyASADemoRG Select Use existing and enter a new resource-group name for your account. Location West US2 Location where the job can be deployed. It's recommended to place the job and the event hub in the same region for best performance and so that you don't pay to transfer data between regions. Hosting environment Cloud Stream Analytics jobs can be deployed to cloud or edge. Cloud allows you to deploy to Azure Cloud, and Edge allows you to deploy to an IoT edge device. Streaming units 1 Streaming units represent the computing resources that are required to execute a job. By default, this value is set to 1. To learn about scaling streaming units, see understanding and adjusting streaming units article.
Use default options on the remaining settings, select Create and wait for the deployment to succeed.
Configure job input
The next step is to define an input source for the job to read data using the event hub you created in the previous section.
From the Azure portal, open the All resources pane, and find the ASATutorial Stream Analytics job.
In the Job Topology section of the Stream Analytics job pane, select the Inputs option.
Select + Add stream input and Event hub. Fill out the pane with the following values:
Setting Suggested value Description Input alias CallStream Provide a friendly name to identify your input. Input alias can contain alphanumeric characters, hyphens, and underscores only and must be 3-63 characters long. Subscription <Your subscription> Select the Azure subscription where you created the event hub. The event hub can be in same or a different subscription as the Stream Analytics job. Event hub namespace myEventHubsNS Select the event hub namespace you created in the previous section. All the event hub namespaces available in your current subscription are listed in the dropdown. Event Hub name MyEventHub Select the event hub you created in the previous section. All the event hubs available in your current subscription are listed in the dropdown. Event Hub policy name Mypolicy Select the event hub shared access policy you created in the previous section. All the event hubs policies available in your current subscription are listed in the dropdown.
Use default options on the remaining settings and select Save.
Configure job output
The last step is to define an output sink for the job where it can write the transformed data. In this tutorial, you output and visualize data with Power BI.
From the Azure portal open All resources pane, and the ASATutorial Stream Analytics job.
In the Job Topology section of the Stream Analytics job pane, select the Outputs option.
Select + Add > Power BI. Then fill the form with the following details and select Authorize:
Setting Suggested value Output alias MyPBIoutput Dataset name ASAdataset Table name ASATable
When you select Authorize, a pop-up window opens and you are asked to provide credentials to authenticate to your Power BI account. Once the authorization is successful, Save the settings.
Define a query to analyze input data
The next step is to create a transformation that analyzes data in real time. You define the transformation query by using Stream Analytics Query Language. The query used in this tutorial detects fraudulent calls from the phone data.
In this example, fraudulent calls are made from the same user within five seconds but in separate locations. For example, the same user can't legitimately make a call from the US and Australia at the same time. To define the transformation query for your Stream Analytics job:
From the Azure portal open the All resources pane and navigate to the ASATutorial Stream Analytics job you created earlier.
In the Job Topology section of the Stream Analytics job pane, select the Query option. The query window lists the inputs and outputs that are configured for the job, and lets you create a query to transform the input stream.
Replace the existing query in the editor with the following query, which performs a self-join on a 5-second interval of call data:
SELECT System.Timestamp AS WindowEnd, COUNT(*) AS FraudulentCalls INTO "MyPBIoutput" FROM "CallStream" CS1 TIMESTAMP BY CallRecTime JOIN "CallStream" CS2 TIMESTAMP BY CallRecTime ON CS1.CallingIMSI = CS2.CallingIMSI AND DATEDIFF(ss, CS1, CS2) BETWEEN 1 AND 5 WHERE CS1.SwitchNum != CS2.SwitchNum GROUP BY TumblingWindow(Duration(second, 1))
To check for fraudulent calls, you can self-join the streaming data based on the
CallRecTimevalue. You can then look for call records where the
CallingIMSIvalue (the originating number) is the same, but the
SwitchNumvalue (country/region of origin) is different. When you use a JOIN operation with streaming data, the join must provide some limits on how far the matching rows can be separated in time. Because the streaming data is endless, the time bounds for the relationship are specified within the ON clause of the join using the DATEDIFF function.
This query is just like a normal SQL join except for the DATEDIFF function. The DATEDIFF function used in this query is specific to Stream Analytics, and it must appear within the
Save the query.
Test your query
You can test a query from the query editor using sample data. Run the following steps to test the query:
Make sure that the TelcoGenerator app is running and producing phone call records.
In the Query pane, select the dots next to the CallStream input and then select Sample data from input.
Set Minutes to 3 and select OK. Three minutes worth of data is then sampled from the input stream and you are notified when the sample data is ready. You can view the status of sampling from the notification bar.
The sample data is stored temporarily and is available while you have the query window open. If you close the query window, the sample data is discarded, and you'll have to create a new set of sample data if you want to test. Alternatively, you can use a sample data JSON file from GitHub, and then upload that JSON file to use as sample data for the CallStream input.
Select Test to test the query. You should see the following results:
Start the job and visualize output
To start the job, navigate to the Overview pane of your job and select Start.
Select Now for job output start time and select Start. You can view the job status in the notification bar.
Once the job succeeds, navigate to Power BI and sign in with your work or school account. If the Stream Analytics job query is outputting results, the ASAdataset dataset you created exists under the Datasets tab.
From your Power BI workspace, select + Create to create a new dashboard named Fraudulent Calls.
At the top of the window, select Add tile. Then select Custom Streaming Data and Next. Choose the ASAdataset under Your Datasets. Select Card from the Visualization type dropdown, and add fraudulentcalls to Fields. Select Next to enter a name for the tile, and then select Apply to create the tile.
Follow the step 5 again with the following options:
- When you get to Visualization Type, select Line chart.
- Add an axis and select windowend.
- Add a value and select fraudulentcalls.
- For Time window to display, select the last 10 minutes.
Your dashboard should look like the example below once both tiles are added. Notice that, if your event hub sender application and Streaming Analytics application are running, your PowerBI dashboard periodically updates as new data arrives.
Embedding your PowerBI Dashboard in a Web Application
For this part of the tutorial, you'll use a sample ASP.NET web application created by the PowerBI team to embed your dashboard. For more information about embedding dashboards, see embedding with Power BI article.
To set up the application, go to the PowerBI-Developer-Samples GitHub repository and follow the instructions under the User Owns Data section (use the redirect and homepage URLs under the integrate-dashboard-web-app subsection). Since we are using the Dashboard example, use the integrate-dashboard-web-app sample code located in the GitHub repository. Once you've got the application running in your browser, follow these steps to embed the dashboard you created earlier into the web page:
Select Sign in to Power BI, which grants the application access to the dashboards in your PowerBI account.
Select the Get Dashboards button, which displays your account's Dashboards in a table. Find the name of the dashboard you created earlier, powerbi-embedded-dashboard, and copy the corresponding EmbedUrl.
Finally, paste the EmbedUrl into the corresponding text field and select Embed Dashboard. You can now view the same dashboard embedded within a web application.
In this tutorial, you created a simple Stream Analytics job, analyzed the incoming data, and presented results in a Power BI dashboard. To learn more about Stream Analytics jobs, continue to the next tutorial:
Send feedback about: