The purpose of this articleis to define distributed system object messaging, classes, and application component tools that may support the future developmental efforts of the university.
Distributed systems are applications that operate on multiple servers through the utilization of various network protocols. These systems are highly scalable and available across geographical boundaries. They can run on various operating systems such as Linux, OSX, and Windows. They can also communicate using multiple protocols like SNA, TCP, Ethernet, and Token Ring (IBM, 2008). An important concept to learn when building applications on a distributed system is the client/server model. In this model there are servers that deliver the application logic and client that manages the display of data to the user. The client is isolated from the application logic so the back-end systems that manage the logic can be updated without affecting the client (IBM, 2008). For instance, if an application built on the client/server model needs to have its database switched from SQL to Oracle, it can without the need to make any changes to the client.
In a modern client/server model there are actually at least three tiers involved in the architecture, presentation, application and data. The presentation tier interacts with the user. The application tier contains the business logic and the data tier houses the databases and data integration services.
When developing distributed applications on a client/server model, it is necessary to implement a programming framework that will work within the model. One model is to use distributed object computing. Technologies such as Java and Microsoft .NET provide this framework by providing object oriented programming methodologies.
In an object-oriented framework, processes are programmed in classes and stored in the application tier. Classes retrieve data from the data tier and deliver it to the presentation tier. Specifically, a class will contain a number of methods that carry out specific tasks. These processes are broken down into a sender, a receiver and a message (Khor, 1995). Typically, a receiver will send a request via a message to the sender, which will respond to the receiver via another method. This process is known as distributed system object messaging.
When working with object-oriented frameworks in a distributed environment, it is helpful to become familiar with the tools that are available for a particular framework. When working with .Net, there are several tools that make development of applications easier. Some of these are ActiveX, .Net add-ins, Provided DLLs and Windows API. These tools are pre-written bits of code the Microsoft provides do developers don’t have to write them for each application they create.
In conclusion, the university should look deeper into these models and processes so they can build scalable and reusable applications that build upon each other rather than standing alone. This memo should provide a good start with its explanations of the relationships between distributed environments, client/server models and object-oriented programming.
Khor, k. (1995). What is Object Oriented Programming.
Retrieved September 2nd, 2009, from IBM
IBM. (2008). What is distributed computing.
Retrieved on September 2nd, 2009 from IBM.
Microsoft. (2009). Components Tools Guide.
Retrieved September 2nd, 2009, from Microsoft
Last Updated (Friday, 30 October 2009 22:42)