# Creating a transport stream flow that uses an entitled source
Transport stream flow, entitled source

Transport stream flows transport compressed content that is muxed into a single stream. An entitled source is content that comes from another AWS account. 

## Prerequisites

+ **NDI® configuration (for NDI use cases only)**

  We recommend reviewing the [NDI outputs](outputs-using-ndi.md) documentation to familiarize yourself with this feature before getting started.

  If you want to add an NDI output to your flow, you need a VPC with NDI discovery servers provisioned in your network. MediaConnect connects to these servers, but it doesn't create them for you. 
  + For a quick start with VPCs, you can use our [AWS CloudFormation VPC template](https://docs.aws.amazon.com/vpc/latest/userguide/create-vpc.html) to automatically create a VPC with public and private subnets. For more information about VPCs, see the [Amazon VPC User Guide](https://docs.aws.amazon.com/vpc/latest/userguide/). 
  + For NDI discovery server deployment, AWS provides guidance on automated setup across multiple Availability Zones using AWS CloudFormation, including best practices for installation and configuration. For instructions, see [Setting Up NDI Discovery Servers for Broadcast Workflows](https://aws.amazon.com/solutions/guidance/programmatic-deployment-of-ndi-discovery-servers-for-broadcast-workflows-on-aws/). 
  + We recommend that you configure your security groups with a self-referencing ingress rule and egress rule. You can then attach this security group to the EC2 instances where your NDI servers are running within the VPC. This approach automatically allows all necessary NDI communication between components in your VPC, and all required network traffic is permitted. For guidance on setting up self-referencing security group rules, see [Security Group Referencing](https://docs.aws.amazon.com/vpc/latest/userguide/security-group-rules.html#security-group-referencing) in the Amazon VPC User Guide.

## Procedure


**To create a transport stream flow that uses an entitled source (console)**

1. Open the MediaConnect console at [https://console.aws.amazon.com/mediaconnect/](https://console.aws.amazon.com/mediaconnect/).

1. On the **Flows** page, choose **Create flow**.

1. In the **Details** section, for **Name**, specify a name for your flow. This name will become part of the ARN for this flow.
**Note**  
MediaConnect allows you to create multiple flows with the same name. However, we encourage you to use unique flow names within an AWS Region to help with organization. After you create a flow, you can't change the name.

1. For **Availability Zone**, choose one of the following options:
   + Select **Any** (recommended)
   + Select a specific Availability Zone (useful if you're setting up redundant flows)

   If you use the default setting (**Any**), MediaConnect will randomly assign an Availability Zone within the current AWS Region. If your source comes from a VPC, the service will assign the Availability Zone of the VPC subnet to the flow.
**Note**  
If your source comes from your VPC, the Availability Zone of your flow must match that of your VPC subnet. We recommend that you leave this as **Any** and let the service ensure that the Availability Zone is set correctly.

1. Under **Flow size**, select the size that matches your use case. For more information about flow sizes, see [Flow sizes and capabilities](flow-sizes-capabilities.md).

   **For medium flows:**
   + Proceed directly to step 6.

   **For large flows:**
   + If you don't need NDI outputs for your flow, proceed directly to step 6.
   + If you want to add NDI outputs to your flow, configure the NDI settings as follows:

     1. Set **Flow NDI support** to **Enabled**.

     1. (Optional) Enter an **NDI machine name**.
        + This name is used as a prefix to help you identify the NDI sources that your flow creates. For example, if you enter **MACHINENAME**, your NDI sources will appear as **MACHINENAME** `(ProgramName)`.
        + If you don’t enter a name, MediaConnect generates a unique 12-character ID as the prefix. This ID is derived from the flow's Amazon Resource Name (ARN), so the machine name references the flow resource.
**Tip**  
Thoughtful naming is especially important when you have multiple flows creating NDI sources. For example, a production environment with 100 NDI sources would benefit from clear, descriptive machine name prefixes like `STUDIO-A`, `STUDIO-B`, `NEWSROOM`, and so on. 

     1. Add up to three **NDI discovery servers**. For each server, provide the following information:
        + Enter the server IP address from your existing NDI infrastructure.
        + Select the VPC interface adapter to control network access.
        + (Optional) Specify a port number. If you leave this blank, MediaConnect uses the NDI Discovery server default of TCP-5959.
**Tip**  
You can add up to three discovery servers. Having multiple discovery servers improves reliability and helps ensure your NDI sources are discoverable across your network.

1. In the **Source** section:
   + For **Source type**, choose **Entitled source**.
   + For **Entitlement ARN**, choose the appropriate entitlement. This list includes all entitlements that have been granted to you.
**Tip**  
You can click in this field and start entering the entitlement name. MediaConnect will filter the list to include only entitlements with a name that matches what you enter.

1. Under **Source monitoring configuration**, choose which monitoring features you want to enable.

   1. Turn on **Thumbnails state** to generate source thumbnails that you can preview in the console.

   1. Turn on **Content quality analysis state** to monitor for the following audio and video quality issues.

      1. (Optional) Turn on **Black frames** to detect periods of black video frames in the stream.

      1. (Optional) Turn on **Frozen frames** to detect periods of unchanging video frames in the stream.

      1. (Optional) Turn on **Silent audio** to detect periods of audio silence in the stream.

      1. (Optional) Set a duration threshold between 10 and 60 seconds for each metric that you enable. The default is 30 seconds.

1. Choose **Create flow**.

## Next steps


Now that you've created a flow, complete these steps to start delivering your content:
+ [Add outputs](outputs-add.md) to specify where you want your MediaConnect flow to send your content
+ [Grant entitlements](entitlements-grant.md) to allow users of other AWS accounts to subscribe to your content
+ [Start your flow](flows-start.md) to begin content delivery

## Additional resources


For more information about source monitoring options for your flow, see the following pages in this guide:
+ [Viewing thumbnails of the source video](monitor-with-thumbnails.md)
+ [Monitoring with content quality analysis in AWS Elemental MediaConnect](https://docs.aws.amazon.com/mediaconnect/latest/ug/monitor-content-quality-analysis.html)