# Undesired Content and Viewers in IVS
<a name="undesired-content"></a>

Malicious users may try to re-stream undesired content (e.g., professional sports) on your platform. This kind of streaming can dramatically increase the amount of live-streamed video that your application is serving as well as the costs associated with it, without adding value to your business. In addition to providing you with controls to stop active streams, Amazon IVS provides resources to help detect and prevent this kind of behavior in the first place.

## Detecting Undesired Content
<a name="undesired-content-detect"></a>

### Anomaly Detection
<a name="undesired-content-anomaly-detection"></a>

You can detect and alert on the kind of anomalous spike in viewership that happens when certain undesired content is being streamed. (Once you detect that a spike has occurred, you can take the steps mentioned in [stop the stream and reset the stream key](#undesired-content-stop-stream), as discussed below.)

Amazon CloudWatch allows you to create alarms which can send alerts under specific circumstances; for example, when your viewership spikes. Amazon IVS automatically reports concurrent views (CCV) metrics to Amazon CloudWatch for all your channels, so you only need to set up an alarm. To set up an anomaly-detection alarm based on CCV, follow these steps:

1. Open the Amazon CloudWatch console at [https://console.aws.amazon.com/cloudwatch/](https://console.aws.amazon.com/cloudwatch/).

1. On the left navigation bar, select **Alarms**, then select **All alarms**.

1. On the top right of the page, select **Create alarm**.

1. Select **Select Metric**. Under *Metrics*, select **IVS**, then **All**, then select the checkbox next to **ConcurrentViews**.

1. On the lower right, select **Select metric**. A 4-step alarm-creation wizard opens.

1. Wizard: In **Step 1, Specify metric and conditions**, specify these settings:

   1. **Statistic** = **Maximum**

   1. **Period** = **1 minute**

   1. **Threshold type** = **Anomaly Detection**

   1. **Whenever concurrent views is…** = **Greater than the band**

   1. **Anomaly detection threshold** = **3**

      This threshold value is an initial suggestion. You may want to select a different value depending on your typical traffic patterns and needs. Use a lower value to watch your metrics more closely; a higher value, to get fewer alarms.

   1. Select **Next**.

1. Wizard: In **Step 2, Configuration actions**, choose an existing SNS topic or create a new one, to send email to an address you specify. To create a topic which sends an email, select **Create new topic**, provide a topic name, enter your email address, and select **Create topic**. Select **Next** to continue.

1. Wizard: In **Step 3, Add name and description**, add a name and optional description for the alarm, then select **Next**.

1. Wizard: In **Step 4, Preview and create**, verify that the information is correct, then select **Create alarm**.

1. Your alarm is created. If prompted, follow any instructions for confirming SNS subscriptions.

For more information, see:

1. [Monitoring Amazon IVS Low-Latency Streaming](stream-health.md)

1. [Creating a CloudWatch alarm based on anomaly detection](https://docs.aws.amazon.com//AmazonCloudWatch/latest/monitoring/Create_Anomaly_Detection_Alarm.html)

### Custom Content Moderation
<a name="undesired-content-custom-moderation"></a>

You can explore custom content-moderation solutions to detect undesired content via image recognition. Amazon IVS provides the ability to [automatically record Amazon IVS live streams to Amazon S3](record-to-s3.md), including the generation of thumbnail images for use in this kind of solution.

Consider these additional detection and prevention techniques:
+ The [Amazon IVS moderation with Amazon Rekognition](https://github.com/aws-samples/amazon-ivs-moderation-with-record-to-s3-web-demo/) demo showcases how to use IVS Auto-Record to S3 in conjunction with Amazon Rekognition to moderate live content.
+ [Add Hive content moderation to your Amazon IVS video streams](https://aws.amazon.com/blogs/media/add-hive-content-moderation-to-your-amazon-ivs-video-streams/)
+ [Creating Safer Online Communities with AI/ML Content Moderation ](https://dev.to/aws/creating-safer-online-communities-with-aiml-content-moderation-1bn)is a blog post about using Amazon Rekognition within an IVS application.

## Preventing Undesired Content and Viewers
<a name="undesired-content-prevent"></a>

### Stop the Stream and Reset the Stream Key
<a name="undesired-content-stop-stream"></a>

If you detect that a channel is being used to stream undesired content, you can use the Amazon IVS console to shut down the stream:

1. Open the [Amazon IVS console](https://console.aws.amazon.com/ivs). (You can also access the Amazon IVS console through the [AWS Management Console](https://console.aws.amazon.com).)

1. If needed, from the navigation bar, use the **Select a Region** drop-down to choose the region in which the channel is hosted.

1. Select the channel on which the stream that you want to stop is running.

1. On the channel page, navigate down to the **Live Stream** section and select **Stop stream**.

Even after you stop the stream, the broadcaster can restart the stream on that channel. To prevent this, reset the stream key; that prevents the broadcaster from restarting a stream without first acquiring a new stream key. To reset the stream key:
+ While still on the channel page, navigate down to the **Stream configuration** section and select **Reset stream key**.

You also can stop a stream and reset (delete/create) the stream key programmatically. See the [Amazon IVS Low-Latency Streaming API Reference](https://docs.aws.amazon.com/ivs/latest/LowLatencyAPIReference/Welcome.html).

Depending on how your application issues stream keys, you may need to take further measures to prevent any new stream keys from being acquired.

### Use Private Channels
<a name="undesired-content-private-channels"></a>

In many cases, undesired content is streamed to a large audience outside of your platform by simply embedding the playback URL in a third-party website. The best solution to prevent this kind of behavior is Amazon IVS private channels. By using private channels, you can restrict playback to viewers with valid playback tokens. Playback tokens are used to validate the viewer within the playback application, impeding viewership on unintended platforms. In addition, you can enable origin enforcement, which prevents viewers from watching streams on websites that aren't hosted on your domains. You can extend this protection to cover common streaming applications by also enabling strict origin enforcement.

Note that you can get the protection of private channels and authentication without forcing users to create and/or log in to formal accounts. Your playback application can simply acquire a token anonymously behind the scenes. You’ll still be able to take advantage of origin enforcement.

To learn more about private channels, see:
+ [Setting Up Private Channels](https://docs.aws.amazon.com//ivs/latest/LowLatencyUserGuide/private-channels.html) in the *IVS Low-Latency Streaming User Guide*. Within that document, to learn more about origin enforcement, see [Generate and Sign IVS Playback Tokens](https://docs.aws.amazon.com//ivs/latest/LowLatencyUserGuide/private-channels-generate-tokens.html).
+ [Creating a Private Channel for Authorized Live Stream Playback with Amazon IVS](https://dev.to/aws/creating-a-private-channel-for-authorized-live-stream-playback-with-amazon-ivs-2mdl) (blog post)

### Use Playback Restriction Policies
<a name="undesired-content-restriction-policies"></a>

If you do not want to use [private channels](#undesired-content-private-channels), you can still benefit from some of the same protections by leveraging playback restriction policies. These policies allow you to enable features such as GeoBlocking and origin enforcement on public channels. You create a playback restriction policy using the IVS console or API, then attach the policy’s ARN to your channels.

#### Console Instructions (Playback Restriction Policy)
<a name="console-playback-restrictions"></a>

1. Create a playback restriction policy

   1. [Open the Amazon IVS console](https://console.aws.amazon.com/ivs). On the left navigation pane, select **Playback security > Playback restriction policies**.

   1. Select **Create policy**.

   1. Optionally, name the policy.

   1. Optionally, toggle **Strict origin enforcement** (see note below).

   1. Specify **Allowed countries** and **Allowed origins**.

   1. Select **Create policy**.

1. Attach this policy to a new or existing channel

   1. Create a new channel or edit an existing channel.

   1. In the **Restrict playback section** (of the **Create channel** or **Update channel** window), select **Enable playback restriction**.

   1. From the **Playback restriction policy** drop-down list, select the policy you created in Step 1.

   1. Select **Create channel** (for a new channel) or **Save** (to update an existing channel).

**Note on strict origin enforcement:** This is an optional setting that can be used to strengthen the origin restriction specified with allowed origins. By default, the origin restriction applies only to the multivariant playlist. If strict origin enforcement is enabled, the server will enforce a requirement that the requesting origin matches the policy for all playback requests (including multivariant playlist, variant playlist, and segments). This means that all clients (including non-browser clients) will have to provide a valid origin-request header with each request. Use the `setOrigin` method to set the header in the IVS iOS and Android player SDKs. It is set automatically in web browsers except iOS Safari. For iOS Safari, you need to add `crossorigin="anonymous"` to the video element, to ensure that the origin request header is sent. Example: `<video crossorigin="anonymous"></video>`.

**Note on mapping between IP addresses and countries:** IVS determines the location of your users by using a third-party database. The accuracy of the mapping between IP addresses and countries varies by region. Based on recent tests, the overall accuracy is 99.8%. If IVS can't determine a user's location, IVS serves the content that the user requested.

#### CLI Instructions (Playback Restriction Policy)
<a name="cli-playback-restrictions"></a>

1. Create a playback restriction policy. Here is an example. *For the `allowed-countries` and `allowed-origins` fields, replace the example values below with your actual values, or delete one or both fields, depending on your use case.*

   ```
   aws ivs create-playback-restriction-policy --name test-playback-restriction-policy --enable-strict-origin-enforcement --allowed-countries "US","JP" --allowed-origins "https://example1.com","https://*.example2.com"
   ```

   This returns a new playback restriction policy. For its fields, see [PlaybackRestrictionPolicy](https://docs.aws.amazon.com//ivs/latest/LowLatencyAPIReference/API_PlaybackRestrictionPolicy.html) in the *IVS Low-Latency Streaming API Reference*.

1. Attach the new policy to a channel. For an existing channel, run `update-channel` and pass in the ARN of the playback restriction policy created in the previous step:

   ```
   aws ivs update-channel --arn "arn:aws:ivs:us-west-2:123456789012:channel/abcdABCDefgh" --playback-restriction-policy-arn "arn:aws:ivs:us-west-2:123456789012:playback-restriction-policy/abcdABCDefgh"
   ```

   For a new channel, include the `--playback-restriction-policy-arn` statement during [channel creation.](create-channel-cli.md)