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+
+Overview of the binder
+======================
+
+The ***binder*** provides the way to connect applications to
+the services that it needs. It provides a fast way
+to securely offer APIs to applications written in
+any language and running almost anywhere.
+
+The ***binder*** is developped for AGL.
+
+The ***binder*** is the usual name.
+The binary is named **afb-daemon**.
+
+The name **afb-daemon** stands for ***Application
+Framework Binder Daemon***. The word *daemon*, here,
+denote the fact that the ***binder*** makes witchcraft to
+connect applications to their expected services (note that usually
+the term of daemon denotes background process but not here).
+
+Each ***binder*** **afb-daemon** is in charge to bind
+one instance of an application or service to the rest
+of the system, applications and services.
+Within AGL, the connexion between services and/or
+applications is tuned by the AGL framework and
+the AGL system.
+
+The basis of the binder
+=======================
+
+The following figure shows main concepts linked to the ***binder***.
+
+<a id="fig-binder-basis"></a>
+![Figure: binder basis](pictures/basis.svg)
+
+The shown elements are:
+
+* The SECURITY CONTEXT
+
+  The primary intend of any ***binder*** is to provide
+  a secured environment for any application. On AGL, the
+  **security context** is ensured by [Smack][Smack] a security context,
+  the security context of the application or service.
+
+* The BINDER
+
+  This is the central element. It makes possible to run HTML5
+  applications and provides the unified access to APIs provided
+  by the ***bindings***.
+
+  Running a pure HTML5 application doesn't require any ***binding***.
+  in that case , the ***binder*** acts as a simple HTTP server for
+  the web runtime.
+
+* The BINDINGs
+
+  A ***binding*** adds one **API** to the ***binder***.
+
+  An **API** is a set of **verbs** that can be called
+  using either REST over HTTP or a kind of JSON RPC.
+  
+  ***bindings*** are either:
+
+   - dynamically loaded libraries in the ***binder*** process
+   - remote service running on the same host
+   - remote service running on other hosts
+
+  When acting as an HTTP server, the binder treats the language
+  settings of the HTTP resquests to provide internationalized
+  content as specified by
+  [widget specifications](https://www.w3.org/TR/widgets/#internationalization-and-localization).
+
+* The APPLICATION
+
+  An ***application*** connects to the binder to get access to
+  the **API** that it provides or to get its HTTP services to access
+  resources.
+
+Interconnection of binders
+==========================
+
+The AGL framework interprets the **widget/application** manifests
+to setup the ***bindings*** configuration of the ***binders***.
+
+The figure below shows that ***binders*** are interconnected.
+
+<a id="fig-binder-interconnection"></a>
+![Figure: binder interconnection](pictures/interconnection.svg)
+
+The figure shows 4 several **application/service**: **A**, **B**,
+**C** and **D**.
+
+The application **A** might use an **API** that is shown as a
+local ***binbing*** but that in reality runs within the context
+of **D**.
+
+The framework AGL takes care of making the plumbing working.
+