3.1.4.1 Request to Retrieve Caching Information

This event can occur when the application is a caching proxy server. Possible uses for this event include allowing the higher layer to check whether content is available or whether the content can be cached.

The higher layer MUST provide the URL that will be used in the request.

If the InitialRequest value is 0, then the client MUST perform the initialization of the protocol, as specified in section 3.1.3, and set the InitialRequest value to 1.

The client MUST then establish a TCP connection to the server by using the host and port number obtained by parsing the URL.

The client MUST send a GetContentInfo request to the server, adhering to the syntax specified in section 2.2.7.4.

In addition, the common processing steps, as specified in section 3.1.5.1, MUST be followed when sending the GetContentInfo request.

After sending the request, the client MUST wait for the response to be received. How to process the response is specified in section 3.1.5.3.