a subscription mechanism configured to send {HEAD ~ a subscription message} containing said information file specification to a notification mechanism included within {TAIL ~ an information provider apparatus} comprising a server computer executing a server application 
a subscription mechanism configured to send { HEAD ~ a subscription message } containing said information file specification to a notification mechanism included within { TAIL ~ an information provider apparatus } comprising a server computer executing a server application
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH