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--- research:ambientrefs [2006/07/11 21:17] – changed tvcutsem
+++ research:ambientrefs [2007/03/22 17:06] – tvcutsem
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 ===== Ambient References =====
+[[http://prog.vub.ac.be/~tvcutsem/|Tom Van Cutsem]]
 {{ ambientrefs.jpg }}
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 === Design ===
-Ambient references unify two concepts: they are both a peer-to-peer discovery channel //and// an asynchronous communication channel to a remote object. When an ambient reference is **unbound** (i.e. it is a dangling pointer), it is acting as a discovery channel, actively looking for remote service objects in the environment to bind to. Once such a suitable ((What exactly constitutes a "suitable" service is discussed below.)) service object is found, the ambient reference becomes **bound**. Once bound, an ambient reference is a true remote object reference to the remote service. An ambient reference carries //asynchronous// message sends only.
+Ambient references unify two concepts: they are both a peer-to-peer discovery channel //and// an asynchronous communication channel to a remote object. When an ambient reference is **unbound** (i.e. it is a dangling pointer), it is acting as a discovery channel, actively looking for remote service objects in the environment to bind to. Once such a suitable ((What exactly constitutes a "suitable" service is discussed later.)) service object is found, the ambient reference becomes **bound**. Once bound, an ambient reference is a true remote object reference to the remote service. An ambient reference carries //asynchronous// message sends only.
 When the service object to which an ambient reference is bound moves out of communication range, the ambient reference can become unbound again. It becomes a dangling pointer anew and immediately becomes a peer discovery mechanism again: the ambient reference will try to //rebind// to the same or another matching service.
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 In this example code ''<-'' denotes asynchronous message passing. The message passing semantics is as follows: if the ambient reference is unbound when it receives the ''print'' message, the message is //buffered// and kept for later forwarding; if the ambient reference is bound, it immediately forwards the message to its bound service object. Using these basic parameter passing semantics, a programming may safely abstract from the internal state of the ambient reference: even if the reference is unbound at the time it receives the message, it is smart enough to store the message and forward it whenever a matching service is found.
-One may wonder how return values can be acquired from such asynchronous message sends. We use the concept of a **future**, which is a very well known concept that unifies asynchronous message passing with return values. More specifically, the futures employed in the language AmbientTalk are based on the non-blocking futures of the [[www.erights.org|E programming language]]. For more details, we refer to the paper below, but as a teaser, here's how one can notify the user when the print job has been sent:
+One may wonder how return values can be acquired from such asynchronous message sends. We use the concept of a **future**, which is a very well known concept that unifies asynchronous message passing with return values. More specifically, the futures employed in the language AmbientTalk are based on the non-blocking futures of the [[http://www.erights.org|E programming language]]. For more details, we refer to the paper below, but as a teaser, here's how one can notify the user when the print job has been sent:
 <code javascript>
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 === Further Reading ===
-Ambient References: Addressing Objects in Mobile Networks. Tom Van Cutsem, Jessie Dedecker, Stijn Mostinckx, Elisa Gonzalez Boix, Theo D'Hondt, Wolfgang De Meuter. In //Technical Report VUB-PROG-TR-06-10, Vrije Universiteit Brussel//, 2006 [ [[http://prog.vub.ac.be/Publications/2006/vub-prog-tr-06-10.pdf|download]] ]
+  * Object-oriented Collaboration in Mobile Ad Hoc Networks. Tom Van Cutsem, Jessie Dedecker, Wolfgang De Meuter. In //Proceedings of the 9th International Conference on Coordination Models and Languages//, Cyprus, 2007 [ [[http://prog.vub.ac.be/Publications/2007/vub-prog-tr-07-03.pdf|download]] ]
+  * Ambient References: Addressing Objects in Mobile Networks. Tom Van Cutsem, Jessie Dedecker, Stijn Mostinckx, Elisa Gonzalez Boix, Theo D'Hondt, Wolfgang De Meuter. In //Proceedings of the Dynamic Language Symposium - OOPSLA '06: Companion of the 21st annual ACM SIGPLAN Conference on Object-Oriented Programming, Systems, Languages and Applications.// Portland, U.S.A. ACM Press., 2006 [ [[http://prog.vub.ac.be/Publications/2006/vub-prog-tr-06-22.pdf|download]] ]
+  * Ambient References: Addressing Objects in Mobile Networks. Tom Van Cutsem, Jessie Dedecker, Stijn Mostinckx, Elisa Gonzalez Boix, Theo D'Hondt, Wolfgang De Meuter. In //Technical Report VUB-PROG-TR-06-10, Vrije Universiteit Brussel//, 2006 [ [[http://prog.vub.ac.be/Publications/2006/vub-prog-tr-06-10.pdf|download]] ]
 Also see the [[research:posters]] section for a poster describing ambient references graphically.