M365 Changelog: Changes to private Content Delivery Networks (CDN)

MC236026 – A content delivery network is a temporary cache storage location designed to optimizethe user experience by providing static files like images, JavaScript, stylesheets, and font files directly from cache locations closest to the user.

In SharePoint Online there are two primary CDNs that are available to handle your static files. One CDN is public and manages JavaScript, stylesheets, and font files. The other CDN is private and is designed to manage images. The public CDN will remain unchanged at this time and should be enabled to handle your JavaScript, stylesheets, and font files, subject to approval by your compliance, security, and privacy teams.

The current private CDN is moving from being hosted by our 3rd party provider Akamai, to Microsoft Azure. Microsoft Azure CDN is a core service for SharePoint. Microsoft Azure CDN complies with all Microsoft data handling and temporary cache storage standards and as such will be a default feature enabled for all customers.

Key Points:

• Timing: the new private CDN will start rolling out during March 2021 and is expected to be available by June 2021.
• Action: for your information no action required

How this will affect your organization:

Microsoft will automatically enable the new private CDN for your tenant and there is no action required.

If you have already enabled private CDN, or are considering enabling it, then we recommend that you continue to plan to enable the feature as it will immediately benefit your users and optimize your pages. Microsoft will automatically transition existing private CDN configurations from Akamai to Microsoft Azure CDN and no further action is required.

What you need to do to prepare:

You do not need to do anything to prepare.

If you would like to learn more about Microsoft data security, visit the Trust center.

If you have SharePoint sites that contains highly confidential content that should be specifically excluded from using Azure private CDN, then sensitivity labels can be created and added to the CDN exclusion list. Excluding a site from using private CDN may impact the overall performance of the site since images will no longer use the CDN to optimize the viewing experience.

Learn more

• Use sensitivity labels to protect content in Microsoft Teams, Microsoft 365 groups, and SharePoint sites
• How to configure CDN in Office 365 (Office 365 Content Delivery Network (CDN) Quickstart)
• Use Office 365 Content Delivery Network (CDN) with SharePoint Online