This statement, in the latest PRO, section 4, "Encoding of Transport Layer":
. Each HTTP operation MUST use the POST method where the request-URI is the object target of the operation...
conflicts with MOD section 3.1.5, "Operation Targets". In the scenario where the operation "target" is a Job specified by "printer-uri" + "job-id", the operation is "directed at" the Printer object. I presume this is done by placing the Printer's URI in the HTTP request-URI, even though the target in this case is a Job.
See the original message at http://www.egroups.com/list/ipp/?start=4886