Instances

An instance allows:

• An encoder to push streams to our network.
• Our servers to determine how a stream will be published.
• A media player to optimize the viewing experience by dynamically requesting streams of varying quality.

Key information:

• The following actions may take up to an hour before they take effect:

  • Creating an instance
  • Deleting an instance
• A set of unique publishing point URLs and playback URLs are assigned to an instance upon its creation.

• All CDN URLs, including publishing point and player URLs, are case-sensitive.

  It is recommended to copy and paste these URLs when setting up an encoder and media player(s).

• An instance may not be modified after it has been created.
• Learn more about instance settings.
• An instance may be configured to automatically archive live streams to CDN storage.

Creating an Instance

An instance may be created for each live event. Alternatively, once a live event is over, an instance may be reused to stream a different live event.

To create an instance configuration

1. Navigate to the Dynamic Cloud Packaging - Live page.
2. Click New Instance.
3. In the Instance Name option, type the name of the instance that will be created.

4. HLS Only: Use the Encrypt HLS option to determine whether streams generated for this instance should be encrypted.

   Learn more.

5. Use the DVR option to determine whether DVR will be enabled for this instance. Upon enabling this option, define the length, in minutes, of the DVR window.
6. Click Add to create a new instance configuration.

7. View the desired publishing point and playback URLs.

   1. Expand the instance configuration by clicking on it.
   2. From the Publish URL option, select the location closest to the encoder. The corresponding publishing point URL will be displayed directly to the right of that option.
   3. From the Playback URL option, select either "HLS" or "MPEG-DASH." The corresponding playback URL will be displayed directly to the right of that option.

It may take up to an hour before all clients can connect to your newly created instance.

Deleting an Instance

Delete an instance by performing the following steps:

1. Navigate to the Dynamic Cloud Packaging - Live page.
2. Expand the desired instance by clicking on it.
3. Click Delete.
4. When prompted, confirm the deletion of the instance.

An instance configuration can be deleted even if there are clients connected to it. The deletion of an instance will cause all connections to that stream to be dropped.

Reusing an Instance

A single instance configuration may be reused to stream different live events. Before pointing an encoder to a previously used instance configuration, make sure that the following conditions have been met:

• The instance is not currently in use by another encoder.
• The instance's DVR window has elapsed.

• Rules Engine: If a custom cache policy has been applied to the manifest files or the file chunks generated for an instance, then either of the following actions must take place:

  • The TTL for the corresponding manifest files and file chunks must expire.
  • The corresponding manifest files and file chunks must be purged.

Attempting to reuse an instance that does not meet the above conditions may result in playback issues.

Settings

Each instance configuration setting is described below.

Option	Description
Instance Name	Defines the name that will be assigned to the streaming configuration. This name will be incorporated into both the publishing point and playback URL.
Enable SSA	Determines whether the live streams generated from an instance will be archived to CDN storage. This capability is known as Server-Side Archiving (SSA). Learn more. Both Encrypted HLS and Encrypted Key Rotation are incompatible with Server-Side Archiving. This option is only available when the Server-Side Archiving feature has been activated on your account. If this option is not available when creating an instance, please contact your CDN account manager to activate this feature.
Encrypt HLS	Determines whether streams associated with this instance will undergo AES-128 encryption. Encrypted streams can only be decrypted by players that support encrypted HLS (e.g., iOS devices, QuickTime, and Android devices). Key information: Both Encrypted HLS and Encrypted Key Rotation are incompatible with Server-Side Archiving. This option is only available when the Encrypt HLS feature has been activated on your account. If this option is not available when creating an instance, please contact your CDN account manager to activate this feature. This feature does not require additional CDN or player configuration. A player that supports encrypted HLS can automatically play encrypted streams. This feature only affects HLS streams. MPEG-DASH streams are always served in an unencrypted format.
Encrypt Key Rotation	Determines whether the encryption key generated for encrypted HLS will be rotated. If enabled, it also determines the time interval, in seconds, at which the key will be rotated. Both Encrypted HLS and Encrypted Key Rotation are incompatible with Server-Side Archiving. The Encrypt Key Rotation option is only available when the Encrypted Key Rotation feature has been activated on your account. If this option is not available when creating an instance, please contact your CDN account manager to activate this feature.
DVR	Determines whether DVR will be enabled on the current instance and the length of the DVR window (in minutes). For the purpose of this document, DVR provides a viewer with the capability to pause and rewind a live stream. The length of time from the present moment that a viewer can rewind a live stream is known as the DVR window. The length of this DVR window can be set from 5 to 180 minutes (i.e., 3 hours). Upon the completion of a live event, viewers may continue to view the live stream on delay for whichever of the following two conditions is shorter: DVR window length Total live stream length View Sample Scenarios. Sample Scenario #1: In this scenario, viewers will be able to view the live stream until 5 p.m. Live Stream Start Time: 2 p.m. Live Stream End Time: 4 p.m. DVR Window: 60 minutes Sample Scenario #2: In this scenario, viewers will be able to view the live stream until 4:30 p.m. Live Stream Start Time: 3:30 p.m. Live Stream End Time: 4 p.m. DVR Window: 60 minutes A live stream must have a minimum buffer window of 60 seconds. This window exists regardless of whether DVR has been enabled on a stream. Disconnecting a media encoder from our service does not affect an instance's DVR window. This ensures that viewers watching a live stream on delay may view it in its entirety.
Segment Size	This is an advanced setting that requires careful planning. Changing the default value for this setting may cause player incompatibility and playback issues. For more information, please consult your media player's documentation. Determines the size of the segments that will be generated for the instance. Segment size, which is defined in seconds, can be set from 1 - 20 seconds. Default value: 10 seconds Apple recommends segments of 10 seconds to achieve a balance between latency, startup time, and network overhead.