3.1.5.4 Receiving a GetContentInfo Response

The client MUST first follow the steps specified in section 3.1.5.3.

If the value of the Client-Token variable is "WMCacheProxy", and the HTTP status code in the response is equal to 400, and the server version is less than 9.0 according to the Server-Version variable, the client MUST set the value of the Client-Token variable to "NSServer" and use a Describe request instead of a GetContentInfo request to get the server's Cache-Control header. To resubmit the request as a Describe request, it will be necessary to establish a new TCP connection to the server. The client MUST then continue by following the steps specified in section 3.1.4.2.1.

Otherwise, if the HTTP status code indicates that the request succeeded, the server SHOULD report the information in the Cache-Control header to the higher layer.