How to use SRT to distribute live streams

The Stream Targets feature in Wowza Streaming Engine™ live streaming software allows you to send live streams to widely distributed destinations. For example, you can send a live stream from Wowza Streaming Engine to any Secure Reliable Transport (SRT) destination. This allows you to use the SRT destination to deliver the stream to viewers.

This article explains how to set up Wowza Streaming Engine so that you can send a single live stream to any generic SRT destination for distributed delivery. If you're ingesting a source stream in multiple bitrates or transcoding in Wowza Streaming Engine and want to send an adaptive bitrate set of streams to your destination, you must create a Stream Target for each rendition and configure a corresponding stream in your destination. The process will be similar to what's documented here, but see the documentation provided by the destination CDN or service for help configuring it to ingest multiple bitrate streams.

Notes:
  • Wowza Streaming Engine 4.7.3 or later is required to use the Stream Targets feature to send streams to SRT destinations.
  • Important: SRT stream targets are only supported in Linux and Windows installations of the Wowza Streaming Engine software.

Contents


Configure the SRT destination to receive and distribute the stream
Create an application in Wowza Streaming Engine to ingest the live source video
Create a stream target to send the stream to the SRT destination
Enable Stream Targets
Test the connection
More resources

Configure the SRT destination to receive and distribute the stream


Your SRT destination might be almost anything--a third-party CDN or a video-sharing site, perhaps. Sign in to the destination's dashboard or video management tool and create an application or stream that will deliver the live event to viewers. You may need to provide the site with information about your Wowza Streaming Engine setup such as the IP address of the server running Wowza Streaming Engine. You can find the IP address in the Connection Settings panel of the Home page of Wowza Streaming Engine Manager.

After you've configured the live stream or application in the MPEG-TS destination, make note of the stream name and host domain or IP address. You'll need this information when you create the live application in Wowza Streaming Engine that sends the stream to the SRT destination.

Create an application in Wowza Streaming Engine to ingest the live source video


Create a live application in Wowza Streaming Engine that will receive the live stream from an H.264 encoder or camera and send it to the SRT destination for distributed delivery.
 
  1. Sign in to Wowza Streaming Engine Manager, click the Applications tab at the top of the page, and then click live in the contents panel.
     
    Note: This article uses the live application that installs with Wowza Streaming Engine. If you want to use a different live application, select it instead from the contents panel.
  2. In the contents panel, click Sources (Live).
     
  3. Select the camera or encoder that you want to use as your video source, and complete the process of connecting the source to Wowza Streaming Engine. For more information, see How to connect a live source to Wowza Streaming Engine
Notes: Wowza Streaming Engine requires RTMP and RTSP sources to provide a username and password to connect to a live application. For information on how to turn off authentication, see Managing live source authentication settings.

Create a stream target to send the stream to SRT


After the live application is created in Wowza Streaming Engine, it must be configured to send the stream to SRT.
 
  1. In the contents panel, click Stream Targets and then click Add Stream Target.
     
  2. On the Add Stream Target page under Generic Target Destinations click SRT.
     
  3. On the SRT Configuration page, provide the following information:

    • Stream Target Name - A descriptive name for this target setup in Wowza Streaming Engine. The name must be unique and can't contain less-than (<), greater-than (>), colon ( : ), quotation (' and "), forward slash (/), backslash (), pipe (|), question mark (?), asterisk (*), double-dot (..), or tilde (~) characters. For clarity, we recommend including the bitrate in the Stream Target Name.
    • Source Stream Name - The name of the incoming stream that that you specified in Wowza Streaming Engine when you set up the video source. 
    • Destination Host - The hostname or IP address of the SRT destination.
       
    • Destination Port - The port number for your connection.
    • Recovery Buffer - The size, in milliseconds, of the recovery buffer for the SRT stream. If not specified, the default value of 400 is used.
       
    • Secure SRT -  Select the Use secure SRT check box if your source stream is secured with AES encryption. If Use secure SRT is selected, you must specify the Key Length and Passphrase.
      Note: The source stream must be secure for the SRT stream target to use Secure SRT settings. If the source stream is not secure, the stream target's Secure SRT settings aren't used.
      • Key Length - The type of AES encryption determines the length of the key (passphrase). AES-128 uses a 16-character (128-bit) passphrase, and AES-256 uses a 32-character (256-bit) passphrase.
      • Passphrase - The passphrase used to secure the SRT stream. For AES-128 encryption, you must enter a 16-character passphrase; for AES-256, you must enter a 32-character passphrase.

  4. Click Add this target.
Note: If you're sending a stream that has multiple bitrates to your SRT target, you must create a stream target for each rendition. Repeat the steps above in Create a stream target to send the stream to the SRT destination for each rendition that you want to send to the SRT destination for adaptive bitrate playback. The easiest way to do this is to create the first stream target, and then click the Copy icon for the target and change the Stream Target Name, Source Stream Name, and Destination Stream Name in the new target. For clarity, we recommend including the bitrate in the Stream Target Name.

Enable Stream Targets


Before you stream, you must enable the Stream Targets feature for the Wowza Streaming Engine application and the stream target you created.

If you don't see a checkmark next to Stream Targets in the contents panel of the application, click Stream Targets in the contents panel and then click Enable Stream Targets. When prompted, click Restart Now so your change takes effect. When Stream Targets is enabled, a checkmark appears next to Stream Targets in the contents panel and the Stream Targets page shows Status is Enabled.

If the Status of an individual stream target is Disabled, click the Enable icon for the stream in the Actions column.




When a stream target is enabled, its status on the Stream Targets page is one of the following:
 
  • Waiting. The target is enabled but not yet pushing the stream to the target destination because either the target's configured source stream isn't connected to the Wowza Streaming Engine input or Wowza Streaming Engine hasn't finished initializing the connection to the target destination.
  • Active. The stream is actively being pushed to the configured Destination Host IP address and Destination Port(s). The status may also appear as Active if Wowza Streaming Engine is attempting to connect to the SRT destination, but will change to Waiting or Error if the connection fails.
  • Error. The Wowza Streaming Engine instance unsuccessfully tried to push the stream to the configured Destination Host IP address and Destination Port(s). Make sure the target's configured source stream is connected to the Wowza Streaming Engine input. Errors might be due to an invalid target configuration.
The status of each stream target updates automatically if your Wowza Streaming Engine application has fewer than 100 stream targets. If your application has more than 100 stream targets, you can click Refresh to update the status.

Test the connection


Configure your encoder and then test the live stream.
 
  1. Start the stream in the H.264 camera or encoder that's sending the stream to the live application in Wowza Streaming Engine. The live application ingests the live stream and sends it to SRT.
     
  2. In Wowza Streaming Engine Manager, verify that the stream is working:
     
    • Click Incoming Streams in the contents panel and then click the stream name. The stream detail page displays the Status of the stream (Active) as well as details about connections, uptime, and throughput for the live stream.
       
    • Click Stream Targets in the contents panel. The Status of the target should be Active.
  3. Verify that your SRT destination is receiving, publishing, and distributing the stream as you've configured it to do.
  4. Stop the stream in the source camera or encoder to end your test connection.

More resources


 

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