Request/response pairs
----- Original Message -----
From: Martin Stecher
To: OPES Group
Sent: Sunday, February 16, 2003 12:33 PM
Subject: Request/response pairs
Hi.
Yet two other questions regarding OPES request/response pairs:
- Should the protocol require that there is always a response to each
request?
{RP}No, not at all, but I guess this is laid out on the protocol
requirements, isn't it?
While writing the ICAP extension draft, I was informed about an
additional method for logging that has been introduced.
This method sends only "requests" (better notifications) to the
server (to give a REQMOD service information about the downloaded
object from a former REQMOD request for logging purpose).
This method does not expect any response.
Are these messages w/o response something the OPES protocol should
consider or allow or forbid explicitly?
- While connections MUST only initiated from client to server, what is
about requests on that connection?
May it be useful to allow the callout server to send a request back
to the client?
{RP} well, requests back would be a response, isn't it? But I agree that
inside a connection the callout server can issue requests to the opes
processor. Keep alive is one example, various statistics is another,
fail-over is another.
I am thinking here about the keep-alive messages?
It is not only in the interest of the OPES device to check whether
the server is still alive. The callout server could also be concerned
that no new request is coming along an open connection and wants to
verify that the client is not down.
What are your thoughts on this?
Regards
Martin