Suggestion: Partial file transfer.

A suggestion for a new Header field to support partial file transfer. In the normal 
use of HTTP with HTML, many (most?) transfer activities are aborted. This makes a 
cache much less efficient, as it have to re-start the file transfer from its 
beginning.

The suggestion is to add a header field "Starting-Position:" to define the requested 
position in the file.
The server reply header will also hold this entry, but only for requests that used 
it. The absence of the Starting-Position implies that the entire file is returned.

The Content-Length: field is left unchanged, as the entire file size.
The client program should validate that the Date and Content-Length fields didn't 
change from the original file, to make sure that the partial transfer is indeed of 
the same file.

The usage of "Starting-Position" should be limited to client application (not cache 
servers), and are valid for the same session only.

Client program can safely use this option with any server, as it is simply ignored 
by older (current) servers, and by returning the entire file.

Received on Thursday, 24 August 1995 12:48:24 UTC