IPP Mail Archive: IPP> PRO> HTTP Connection: close

IPP> PRO> HTTP Connection: close

Carl Kugler (kugler@us.ibm.com)
Wed, 9 Sep 1998 14:14:26 -0400

Section 4.1, General Headers, says
General Header: Connection
"close" only. Both client and server SHOULD keep a connection for the
duration of a sequence of operations. The client and server MUST includ=
e this
header for the last operation in such a sequence.
Consider the (presumably typical) case of an interactive IPP client wit=
h a user
interface. How is the client to know when the current operation is the=
last of
a sequence of user-initiated actions? Apparently, the only safe way to=
satisfy
the MUST (an absolute requirement of the specification) would be to sen=
d
"close" after each user-initiated action. But this would violate the S=
HOULD,
and is contrary to the recommendations of "HTTP Connection Management",=

http://www.ics.uci.edu/pub/ietf/http/draft-ietf-http-connection-00.txt=

Quoting:
"Authoritative knowledge that it is appropriate to close a connection=

can only come from the user. Unfortunately, that source is not to be=

trusted. First, most users don't know what a connection is, and
having them indicate it is okay to close it is meaningless. Second, =
a
user that does know what a connection is probably inherently greedy.=

Such a user would never surrender the attention that a connection to=

a server implies.
But this is talking about the client actually closing the connection, n=
ot
sending a header to the server to signal that the connection will be cl=
osed
after completion of the response. Obviously, the header can only be sen=
t as
part of a request. Also, "HTTP Connection Management" says clients SHO=
ULD
close connections before servers when possible.
How are you implementing this requirement?

-Carl,
=