Subject: IPP> Re: IPP > FAQ - How should the server behave?

From: "Turner, Randy" <[email-masked]>
Date: Wed, 4 Feb 1998 04:24:29 -0800

The HTTP server that is doing NSAPI, ISAPI, or CGI to a back-end IPP
server will always know the state of it's end of the TCP connection. If
for any reason, the generic HTTP server receives an error indicating
termination of the connection to the client, it will throw away the
response from the CGI IPP server. In this case the IPP client will have
to reconnect and re-issue the IPP request.

On the 2nd issue regarding the 10GB (wow!) print job, unfortunately its
hard to predict what different generic HTTP servers will do with a
PRINT-JOB request to a back-end CGI implementation of an IPP server.
For a dedicated IPP server implementation that might be embedded in a
physical printer, the server would immediately respond back to a client
when an error was detected. And if the error was severe enough, the
server would close the connection to the client so that the remainder of
a very large job would not have to take up network bandwidth for no
reason.

	-----Original Message-----
	From:	[email-masked] [SMTP:[email-masked]]
	Sent:	Tuesday, February 03, 1998 11:55 PM
	To:	[email-masked]; [email-masked]
	Subject:	IPP> Re: IPP > FAQ - How should the server
behave?

	Carl,

	>> 1.     If an IPP-client transmit a request to the IPP-server
and close
	the
	>>   tcp-connection, should the IPP-server open a new
tcp-session and
	transmit the
	>>   esponse?

	>Impossible.  The client isn't listening on a server port.

	Well, maybe the IPP server doesn't know the state of the
tcp-connection.
	However, what
	should the HTTP-stack on the printserver do when it receives the
response
	from the IPP-server
	and the tcp-connection to the client is closed for some reasons.
Should the
	HTTP-stack open
	a new tcp-connection to the client?

	>> 2.     Must the IPP-server wait with the response, on a
print-job
	request, to
	>>   the whole job is received?

	>The server should respond to the request before accepting
appended
	document content.
	>See 3.1.7 and 15.4 in the model document.

	If the IPP-server rejects a 'print-job' request for some
reasons, must the
	server purge
	the appended document? If the document is 10 Gbytes, the server
has to
	purge 10 Gbytes
	data, what a waste of network traffic.

	>> 3.     How should a non-spooling IPP-server handle concurrent
print-job
	>>   requests?

	>Return server-error-service-unavailable (0x0502) to indicate
that the
	server is temporarily unable to >handle a request.

	How should the client respond to this? Is it an error if the
IPP-server is
	printing and
	a second 'print-job' occour? I don't think so!

	___________________________________________________________
	 Henrik Holst
	 Software engineer - developing embedded Printservers
	 i-data International
	 Vadstrupvej 35-43, 2880 Bagsvaerd, Denmark
	 Voice:  (45) 44366271
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