From Network World Fusion: "The PAP (Push And Pull) and POP (Push Or Pull) protocols could
become standard ways for information providers to push updates to
clients in some cases, and let clients pull those updates from a server
in other cases, said Krithi Ramamritham, a professor at the Indian
Institute of Technology (IIT) in Bombay, who presented the concept in
a paper at WWW10."
May 3, 2001