Changes between Initial Version and Version 1 of Tutorial/HowToAppPrototype

Timestamp:

Nov 30, 2007, 5:37:32 AM (17 years ago)

Author:

thierry

Comment:

—

Tutorial/HowToAppPrototype

@@ +1 @@
+Go back --> [wiki:Tutorial Tutorials]
+[[TOC(heading=Tutorial TOC, Tutorial, depth=2)]]
+
+= How to use execute an Application via a Prototype =
+
+=== Prerequisite ===
+
+This feature is only available in NodeHandler v4 and above.
+
+Before going through this tutorial, you should know the basics of writing and running an experiment script (see [wiki:Tutorial/HelloWorld here] and [wiki:Tutorial/HowtoWriteScripts here]).
+
+You should also have installed a disk image with Node Agent v4 on the nodes of the testbed you are using (e.g. "baseline.ndz"). See [wiki:Tutorial/HowToImage "How to install a disk image"].
+
+=== Goal ===
+
+In this tutorial, you will learn a method to execute an application using a prototype. This method is complementary to the two previous methods presented [wiki:Tutorial/HowToCommand here] and [wiki:Tutorial/HowToApplication here]. It is the recommended method if you have an application, which you would like to use in the long term with different (possibly dynamic) parameters. 
+
+For example, this would be the case of a traffic generator that can generate multiple type of traffic depending on the parameters given by the experiment script. Using a prototype to execute this generator within your experiment allows you to:
+ * run the application with different initial parameters without having to re-write any modified "wrapper" code, 
+ * change any eventual dynamic parameters during the application execution (e.g. change the rate of the generated traffic after 60sec)
+
+This method involves three steps:
+ * the definition of a "wrapper" around your original application. This step would correspond to the creation of a generic Node Handler-compatible version of your application.
+ * the definition of a so-called prototype. This step would correspond to the creation of a specific type or instance of your application.
+ * the definition of an experiment script, which would use your application via its prototype.
+
+In the context of the above traffic generator example:
+ * first step: you create an Node Handler-compatible application definition, which is a "wrapper" around your original application. This application definition will provide an interface to all the available parameters of your original application.
+ * second step: you specialize the previous application definition in a prototype definition. For example you decide to define an instance of your application (i.e. a prototype) which will only generate a given traffic model (e.g. pareto) but which still accepts different parameter (e.g. packet size, rate, etc...). You may also decide to define a second prototype, which will generate another type of traffic.
+ * third step: you define an experiment which will use this specialized application.
+
+The remainder of this tutorial describes these three steps and the execution of the related experiment script
+  
+=== Step 1: Application Definition ===
+
+=== Step 2: Prototype Definition ===
+
+=== Step 3: The Experiment Script ===
+
+This experiment is given in the attached script [attachment:a a]. 
+
+This file contains extensive comments that should help you understand the different steps involved in running an application on the nodes of a testbed.
+
+To run this example script, use the following command:
+
+ {{{
+  orbit exec tut_app_1
+ }}}
+
+=== The Results ===
+
+The experiment screen output should then look like [attachment:a this]. And the experiment log file should look like  [attachment:a this].
+
+=== More... ===