HTTP/2 Support in Azure Content Delivery Network
Important
Azure CDN Standard from Microsoft (classic) will be retired on September 30, 2027. To avoid any service disruption, it is important that you migrate your Azure CDN Standard from Microsoft (classic) profiles to Azure Front Door Standard or Premium tier by September 30, 2027. For more information, see Azure CDN Standard from Microsoft (classic) retirement.
Azure CDN from Edgio will be retired on Januray 15, 2025. You must migrate your workload to Azure Front Door before this date to avoid service disruption. For more information, see Azure CDN from Edgio retirement FAQ.
HTTP/2 is a major revision to HTTP/1.1. This technology delivers enhanced web performance, diminished response time, and an elevated user experience, all the while preserving the customary HTTP methods, status codes, and semantics. Though HTTP/2 is designed to work with HTTP and HTTPS, many client web browsers only support HTTP/2 over TLS (Transport Layer Security).
HTTP/2 Benefits
The benefits of HTTP/2 include:
Multiplexing and concurrency
Using HTTP 1.1, making multiple resource requests requires multiple TCP connections, and each connection has performance overhead associated with it. HTTP/2 allows multiple resources to be requested on a single TCP connection.
Header compression
By compressing the HTTP headers for served resources, time on the wire is reduced significantly.
Stream dependencies
Stream dependencies allow the client to indicate to the server which resources have priority.
HTTP/2 Browser Support
All major browsers implement HTTP/2 support in their current versions. Browsers that don't support it automatically falls back to HTTP/1.1.
| Browser | Minimum Version |
|---|---|
| Microsoft Edge | 12 |
| Google Chrome | 43 |
| Mozilla Firefox | 38 |
| Opera | 32 |
| Safari | 9 |
Enabling HTTP/2 Support in Azure CDN
Currently, HTTP/2 support is active for all Azure CDN profiles. No further action is required from customers.
Next Steps
To learn more about HTTP/2, visit the following resources:
To learn more about Azure CDN's available features, see the Azure CDN Overview.