HTTP/2 Support in Azure CDN
HTTP/2 is a major revision to HTTP/1.1. It provides faster web performance, reduced response time, and improved user experience, while maintaining the familiar 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.
HTTP/2 Benefits
The benefits of HTTP/2 include:
Multiplexing and concurrency
Using HTTP 1.1, multiple 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 of resources have priority.
Server push
Server push allows the server to pre-emptively pushing the responses it thinks the client will need into the client's cache.
Note
Server push is not supported in Azure CDN.
HTTP/2 Browser Support
All of the major browsers have implemented HTTP/2 support in their current versions. Non-supported browsers will automatically fallback 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 Azure CDN from Akamai profiles. No further action is required from customers.
HTTP/2 with Azure CDN from Verizon profiles is not currently supported.
Next Steps
To see the benefits of HTTP/2 in action, see this demo from Akamai.
To learn more about HTTP/2, visit the following resources:
To learn more about Azure CDN's available features, see the Azure CDN Overview.