Path: utzoo!utgpu!watserv1!watmath!att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!wuarchive!mit-eddie!uw-beaver!cornell!batcomputer!munnari.oz.au!brolga!uqcspe!batserver.cs.uq.oz.au!kerry From: kerry@batserver.cs.uq.oz.au (Kerry Raymond) Newsgroups: comp.protocols.iso Subject: Re: Transparent Distribution - Why no light-weight transport in OSI stack? Message-ID: <7328@uqcspe.cs.uq.oz.au> Date: 18 Feb 91 02:26:43 GMT Sender: news@uqcspe.cs.uq.oz.au Reply-To: kerry@batserver.cs.uq.oz.au Lines: 36 In article morse@quark.mpr.ca (Daryl Morse) writes: >OSI is pretty clearly aimed at the connection of systems. >This is reinforced by >the preliminary work that I have reviewed on the ODP (Open Distributed >Processing) Reference Model. This also seems to be clearly aimed >providing transparent distribution at the application level. >Why, then, is there no light-weight mechanism for applications to >communicate with other applications that might happen to be located on >the same system? One of the three main aims of ODP is to provide distribution transparency which should blur the distinction between local and remote. To that end, ODP wants to see communication between co-located and non-co-located applications done via the same interface. Whether the implementation of those interfaces is smart enough to realize that some light-weight mechanism can be used in certain circumstances depends on those implementing the lower-level protocols. I suspect that the problem is that the lightest-weight mechanism is usually the local IPC mechanism. However, the implementer wants to write something very portable which can run on many machines and hence isn't interested in including local IPC calls. >Perhaps I'm just impatient, and these issues will be addressed by the ODP work? I doubt that ODP will address the light-weight mechanism issue. I believe that the ODP group would regard that as a problem for lower layers of the OSI stack. =============================================================================== Dr Kerry Raymond, R & D Engineer kerry@citrus.citr.uq.oz.au Centre for Information Technology Research Phone: +61 7 365-4321 University of Queensland 4072 Australia Fax: +61 7 365-4399