Multi-CDN

You may leverage multiple Content Delivery Networks (CDNs) to deliver your content. This type of setup provides higher availability and better performance by providing the means through which traffic can be shifted when a CDN is experiencing network congestion or issues. It also allows traffic distribution to be tailored according to geographic region, in order to leverage regional performance benefits.

Terminology

Key terms for understanding Multi-CDN are described below.

Term	Description
Playback Session	A playback session identifies the time period during which a viewer plays your content. A playback session starts when the player initiates playback. At which time, the system assigns a unique ID to the player's session. This session persists until the user closes the player/web browser/device playback environment or the session has been inactive for an extended time period. A single playback session may represent the playback of multiple assets and/or channels. Example: A user loads a web page that contains an autoplay video. This causes the video player on that web page to initiate a new playback session. Alternatively, playback requests that occur halfway through the video simply continue an existing playback session.
Profile	A profile is a configuration that identifies one or more CDNs and when playback sessions may leverage them. A profile configuration defines its priority, identifies traffic via rule sets, and determines how playback sessions will be distributed between one or more CDN(s).
Priority	Priority, which is a profile setting, determines the order in which profiles evaluate playback sessions. Profiles with lower priority values are evaluated before those with a higher priority value. A playback session will be assigned the first profile whose rule set(s) it can satisfy.
Rule Sets	A rule set identifies playback sessions by content, playback session ID, and/or by player-specific information A profile leverages one or more rule sets to identify playback sessions.
CDN Distribution	This profile setting defines the percentage of playback sessions that will be distributed to each CDN.

How Does It Work?

A CDN service provider is assigned to a playback session using the following workflow:

Step	Name	Description
1	Profile Selection	A playback session will be assigned the profile with the highest priority for which it qualifies. The criteria defined within the rule set(s) associated with a profile determine whether the profile may be applied to the playback session. If a playback session does not qualify for any of your profiles, then it will be assigned the catch_all profile. View this profile from the Profiles tab of the Multi CDN Settings page.
2	CDN Selection	A CDN will be assigned to the playback session according to weighted values.

Setting up Multi-CDN

Setting up Multi-CDN involves the following steps:

1. Contact your account manager to activate the desired CDN service providers on your account.

   Your account manager will inform you when you may proceed with your Multi-CDN setup.

2. Determine how playback sessions may be identified by creating one or more rule sets.
3. Define how the traffic identified in the previous step will be distributed via one or more profiles.

Rule Sets

A rule set identifies playback sessions by content, playback session ID, and/or by player-specific information.

Assign one or more rule sets to a profile to identify the type of playback sessions for which it can assign a CDN for content delivery.

A default rule set called catch_all cannot be modified or deleted. This rule set matches all playback sessions.

To create a rule set

1. Navigate to the Rule Sets tab of the Multi CDN Settings page. How?From the main menu, navigate to Settings. From the side navigation bar, click Multi CDN Settings.
2. Click + Rule Set.
3. From the Rule Set name option, type the desired name and then click Add.

4. Add the desired criteria through which playback sessions will be identified.

   1. Navigate to the Content Rules, Playback Rules, or Client Rules tab.

      Learn more about fields.

   2. Click + Add New Rule.
   3. From the Field option, select the desired field.

   4. From the Operator option, select the desired mathematical operator.

      Learn more about mathematical operators.

   5. Click Add Rule.
   6. From the Value to Match option, type the desired value.
5. Repeat step 4 as needed.
6. Click Apply Changes to create this rule set.

To update a rule set

1. Navigate to the Rule Sets tab of the Multi CDN Settings page. How?From the main menu, navigate to Settings. From the side navigation bar, click Multi CDN Settings.
2. From the Rule Sets list, select the desired rule set.

3. Perform one of the following actions:

   • Add a field match condition to this rule set by performing the following steps:

     1. Navigate to the Content Rules, Playback Rules, or Client Rules tab.

        Learn more about fields.

     2. Click + Add New Rule.
     3. From the Field option, select the desired field.

     4. From the Operator option, select the desired mathematical operator.

        Learn more about mathematical operators.

     5. Click Add Rule.
     6. From the Value to Match option, type the desired value.
   • Update a field match condition for this rule set by navigating to the desired tab and then making the desired changes inline.
   • Delete a field match condition from this rule set by clicking the x that appears directly to the right of it.
4. Repeat step 3 as needed.
5. Click Apply Changes to save your changes.

To delete a rule set

1. Navigate to the Rule Sets tab of the Multi CDN Settings page. How?From the main menu, navigate to Settings. From the side navigation bar, click Multi CDN Settings.
2. From the Rule Sets list, select the desired rule set.
3. Click Delete Rule Set.
4. When prompted, confirm the deletion by clicking Yes, Delete.

Profiles (CDN Distribution)

A profile determines how playback sessions will be distributed to each CDN. A profile identifies playback sessions via one or more rule set(s).

A default profile called catch_all cannot be modified or deleted. This profile is applied to all playback sessions that are not assigned to another profile.

The order in which profiles evaluate playback sessions is determined by priority. The profile with the lowest priority wins. Once a match is found, the playback session will be assigned that profile and no additional profiles will be evaluated.

Learn more about how playback sessions are assigned to a CDN.

Ensure that a specific profile is evaluated first by setting its priority to 1.

A profile's priority must be set to a unique value.

The order in which profiles are listed is irrelevant.

To create a profile

1. Navigate to the Profiles tab of the Multi CDN Settings page. How?From the main menu, navigate to Settings. From the side navigation bar, click Multi CDN Settings. Click the Profiles tab.
2. Click + Profile.
3. From the Profile name option, type the desired name and then click Add.
4. Determine whether to activate this profile via the Enabled option.

5. Mark the Override Client CDN option if a client's preferred CDN will be overridden to comply with the CDN distribution defined within this profile.

   Please contact your account manager to learn how a client can indicate a preferred CDN during playback.

6. From the Priority option, define a unique value between 1 and 499.

   This value determines the order in which profiles will evaluate playback sessions. The profile with the lowest priority value wins.

7. Add one or more rule sets to the profile by performing the following steps:

   1. From the Add Rule Set option, select the desired rule set and then click + Rule Set.
   2. Repeat the previous step as needed.

   A playback session will only be assigned to a profile when it satisfies all of the criteria defined within each rule set associated with the profile.

8. Determine the set of CDNs that will deliver content for the traffic identified in the previous step.

   1. From the Add CDN option, select the desired CDN service provider and then click + CDN Distribution.
   2. From the Percentage option, define the percentage of playback sessions that will served by the CDN selected in the previous step.
   3. Add another CDN by repeating steps i and ii.
   4. Verify that the sum of the percentages assigned to each CDN adds up to 100%. If it doesn't, please adjust the percentages until it does.
9. Click Apply Changes to create this profile.

To update a profile

1. Navigate to the Profiles tab of the Multi CDN Settings page. How?From the main menu, navigate to Settings. From the side navigation bar, click Multi CDN Settings. Click the Profiles tab.
2. From the Profiles list, select the desired profile.

3. Perform one of the following actions:

   • Add a rule set by selecting the desired rule set from the Add Rule Set option and then clicking + Rule Set.

   • Remove a rule set by clicking the x that appears directly to the right of it.
   • Add, modify, or delete a CDN distribution configuration as needed.
4. Repeat step 3 as needed.
5. Click Apply Changes to save your changes.

To delete a profile

1. Navigate to the Profiles tab of the Multi CDN Settings page. How?From the main menu, navigate to Settings. From the side navigation bar, click Multi CDN Settings. Click the Profiles tab.
2. From the Profiles list, select the desired profile.
3. Click Delete Profile.
4. When prompted, confirm the deletion by clicking Yes, Delete.