Chunked Transfer Encoding

Add this behavior to allow or deny Chunked Transfer Encoding (CTE) requests to your origin.

Why you need it

Enable CTE if these points apply:

  • You have clients that might send CTE requests. If you have the HTTP/2 behavior enabled for your property, check whether any clients might send CTE requests. If so, it is important to enable the CTE behavior as well. Without it, our CDN responds to CTE requests with a DoS.

  • Your property uses both HTTP/2 and WebDAV behaviors. With both, you need to allow CTE. This will protect against a Denial of Service (DoS). Because of the way some browsers handle WebDAV, they might send HTTP/2 requests that ​Akamai​ must forward to your origin using CTE over HTTP/1.1. Allowing CTE in your property configuration and on your origin ensures that these requests can get to your origin.

How it works

CTE is a type of encoding that improves performance when a client request includes a large amount of content. CTE breaks the content into chunks and sends them separately, so that a single request with a longer download time doesn't continuously occupy a connection. Smaller requests are free to use the connection between chunks.

By default, ​Akamai​ denies requests to your origin that use Chunked Transfer Encoding (CTE). If you have any clients that might send CTE requests, enable this behavior to ensure those clients can access your website.

This behavior doesn't include any options. Specifying the behavior itself enables it.

Caveats and known issues

Consider these points when adding CTE support:

  • You need it on your origin server. If you configure your property to allow CTE, make sure you also enable it on your origin.

  • Older transfer encoding methods indicate the size of the content at the start of the request. CTE doesn't have this requirement, so it can start sending the request even if the length is unknown. This can improve performance by reducing the time to the first byte.