Hi I created the layers concept for the C++ Networking boost library. The layers I defined are: Layer 1 :- Light weight wrappers arround predominantl BSD socket concepts. Layer 2 :- Acceptor, Connector, Reactor, and Svc_Handler concepts ala ACE. Layer 3 :- An optional iostreams interface if desirable? Layer 4:- Applications layer - includes ftp, telent, http/s And user applications Please note there is no Layer 0 ( zero ) it does not exist. These layers are a key to understandable discussion on the list and avoidance of confusion. This makes Don G's propasal a Layer 2 porpasal IIUC. There have been other proposals at Layer 2. Boris has also been atempting bto model Layer 1 but keeps calling itlayer 0. we need a common nomenclture or confusion will reign. /ikh