Set up an SRT stream using rendezvous mode

Secure Reliable Transport (SRT) is an open-source streaming protocol that offers quality, low latency streaming to CDNs and other SRT enabled decoders across unreliable Internet connections via UDP.

The easiest way to establish a link between the SRT source and destination devices is to use rendezvous mode. In rendezvous mode, both the SRT source and destination device are ready to establish the SRT connection as soon as an SRT stream starts.

Typically, no intervention is needed from your IT administrator to traverse a firewall in rendezvous mode. However, you can switch to SRT caller and listener modes if you experience difficulties streaming through a firewall in rendezvous mode, see Set up an SRT stream using caller and listener modes.

To establish the SRT connection between the source and destination devices in rendezvous mode, both devices must be configured and ready to establish the connection between them. Each must know the IP address of the other device and both must be configured to use the same port for the SRT stream.

In the following example, a Pearl-2 is setup as SRT Source A (192.168.1.10) with port 20000 and another Pearl-2 is setup as SRT Destination B (203.0.113.10) with port 20000.

Source A streams through Firewall A and Firewall B to Destination B, which ingests the SRT stream as a video input with embedded audio. All traffic received at Firewall B that's addressed to 168.112.1.1 on port 20000 passes through the firewall directly to Destination B (203.0.113.10) because of the port number.

What's needed for this setup

  • The public IP address of Source A (e.g. 198.51.100.20) and the public IP address of Destination B (e.g. 168.0.113.10).
  • The SRT streaming port that Source A is configured to use (e.g. port 20000).
  • Configure SRT Destination B to use the same port value as Source A for the SRT stream (e.g. 20000). If the destination device is another Pearl-2, you do this when adding the SRT stream as a video input source using the Admin panel, see Connect an SRT stream as an input.

When you're configuring an SRT stream on Pearl-2, you can also adjust the recovery bandwidth overhead using the Admin panel. This setting defines how much of the stream's total bandwidth is dedicated for the exchange of SRT control and recovery packets between the source and destination. Ensure that the total SRT stream bitrate (i.e. the bandwidth required for the stream plus the recovery bandwidth overhead) is less than the network bandwidth you have available.

Set up Pearl-2 as a streaming source in rendezvous mode using the Admin panel

  1. Login to the Admin panel as admin, see Connect to Admin panel.
  1. From the Channels menu, select the channel and click Streaming. The Streaming configuration page opens.
  2. Click New stream and choose SRT push. The new stream with the default name Stream 1 is created.

  1. Click the stream name to expand the stream settings.
  2. In the Connection mode field, select Rendezvous.
  3. Enter the URL of the SRT destination (decoder) using the format srt://<decoder-ip-address>:<port>, where the <decoder-ip-address> and <port> values are provided by the CDN, media server, or an SRT decoder device such as a second Pearl-2 at the destination.
  4. (Optional) Check Encryption and choose the AES key length if the SRT destination requires AES encryption. These settings must match the encryption settings of the destination device, see Set AES encryption and a passphrase for SRT.
  5. (Optional) If the SRT destination has a required security Passphrase along with the AES encryption, you can enter that here.
  6. (Optional) In the Latency field adjust the amount of latency to apply to the stream. The default value is 125 ms.

    7. We recommend using the default latency and recovery bandwidth overhead values for an initial test stream. After you perform a test stream, you can determine the Quality of Service (QoS) and calculate the latency requirements. To set the SRT stream latency, see Adjust latency and view the SRT stream status.

  7. (Optional) In the Recovery bandwidth overhead field, adjust the % value of the bandwidth that's dedicate for SRT control and recovery packets. The default value is 25%.
  8. (Optional) Rename the stream. Click the current name and enter a different name, then press Enter.

    9. Refresh your browser if the new stream name doesn't immediately display.

  9. Click Apply.
  10. When your ready to start streaming, click Start

What's next?

If you also need to set up Pearl-2 as an SRT destination and ingest an SRT stream from a remote source, you must add the SRT stream as a input, see Connect an SRT stream as an input.