November 1, 2014
1. Define software. Explain how system software is different from application software. Describe networking operation system (NOS). Describe enterprise applications. Differentiate between a horizontal system and a vertical system. Define legacy systems.
Software is the computer programs that govern the operation of the computer.
System software is used for basic computer operations such as startup and printing for example Windows 7. Whereas, application software such as Microsoft Office 2010 allows you to perform specific tasks such as word processing and tabulation of numbers.
(Stair & Reynolds, 1992, p.14).
“A network operation system (NOS) is a systems software that controls the computer systems and devices on a network and allows them to communicate with each other” (Stair & Reynolds, 1992, p.254). Much like how the operating system software performs for the computer, NOS offers task management, memory, and coordination of hardware for the network. Some examples of this would be Novell NetWare and Windows 2008 (Stair & Reynolds, 1992, p.254).
“An enterprise application is a business application, obviously. As most people use the term, it is a big business application. In today’s corporate environment, enterprise applications are complex, scalable, distributed, component-based, and mission-critical. They may be deployed on a variety of platforms across corporate networks, intranets, or the Internet. They are data-centric, user-friendly, and must meet stringent requirements for security, administration, and maintenance. In short, they are highly complex systems” ("Chapter 1: What is an enterprise application?", 2014).
With horizontal systems you keep adding more systems to help with the increases in demand. So if you need have 3 systems that work on Node, and your load gets higher you add another system with Node to help with the load. Vertical systems references that instead of adding more systems, you get better machines to handle the load. So each client will play a different role. You will have one server that handles Authentication and another for Node (Milewski, 2011).
“In computing a legacy system is an old method, technology, computer system, or application program; of, relating to, or being a previous or outdated computer system. Often a pejorative term, referencing a system as "legacy" often implies that the system is out of date or in need of replacement. A more recent definition says that a legacy system is any corporate computer system that isn't Internet-dependent” ("Legacy system", 2014).
2. Describe object-oriented analysis (O-O) and objects. Define class and properties. Define methods. Define messages.
Object-oriented analysis “views the system in terms of objects that combine data and process. Whereas Structured Analysis treats processes and data as separate components, object-oriented analysis combines data and processes that act on the data into things called objects. The objects represent actual people, things, transactions, and events. Compared to structured analysis, object-oriented phases tend to be more interactive. Some of the advantages that object oriented analysis offers are that it integrates easily with object oriented programming languages such as Java, Small talk, C++, and Perl. Programmers also like O-O code because it is modular, reusable, and easy to maintain. In other words, a major advantage of O-O designs is that systems analyst can save time and avoid errors by using modular objects, and programmers can translate the designs into code, working with reusable program modules that have been tested and verified” ("Object-Oriented (O-O) Analysis | System Development Method | System Design Development", 2012).
“In object-oriented programming, a class is an extensible program-code-template for creating objects, providing initial values for state (member variables) and implementations of behavior (member functions,