Re: holding connections open: a modest proposal

John Ludeman (
Mon, 12 Sep 1994 22:52:51 +0200

In article <>, David Kristol writes:
> There has been some discussion here about keeping connections open
> between client and server after a transaction is complete. I don't
> recall seeing a resolution, however, so I want to put forth what I
> think is a simple solution, and I don't recall seeing anything
> comparable proposed.

On the www-speed alias we discussed this a couple of months ago. One
of the (simple) solutions we came up with was suggested by Gary Adams.
He suggested adding a Pragma: Keep-connection header. The behaviour
goes something like:

1) Client sends "Pragma: Keep-connection\n" along with the rest of the headers.
2) If the server supports this pragma, in the reply headers to the
client, it includes "Pragma: Keep-connection\n" (real protocol negotition)

At this point, either party can terminate the connection. Generally,
the client will terminate the connection after it has retrieved all of
the pieces of the document being viewed (suggested behaviour) or the
server will terminate the connection based on inactivity by the client
or server load.

Code changes to support this on both the server and the client are very

We tended to stay away from MGET (as valuable as it may be) or other
new methods as those should really be part of the next HTTP definition.
The Keep-connection pragma allows good interop with virtually no
changes to clients while addressing the basic problem of numerous
session setups retrieving a single document. I think some people are
working on reference implementations now.

I haven't seen any complete digests of the www-speed alias. Can
somebody give a pointer?