Introduction to Information Systems

Posted on Aug 21, 2024 in Computers

Meaning of System: A set of things neatly interrelated, contributing to a given objective.

Elements of a System:

  • System components.
  • The relations between them that determine the structure of the system.
  • The purpose of the system.
  • The system environment: that which surrounds it, within which it is located.
  • The system boundaries: the boundary between what the system is and what constitutes the environment.

For data to be transformed into information, data operations are needed that add value to the user.

  • Capture: Act of recording data.
  • Verify: Validating.
  • Classifying: Separated by categories.
  • Sort: Place them in sequence.
  • Summarize and Calculate: To give a logical sense.
  • Storing: Action to save.
  • Recover
  • Copy: An example of PC role.
  • Distributed: Give the user.

Characteristics of Information:

  • Available: Easy and fast to obtain.
  • Precise: No errors.
  • Relevant: Used for the decision that requires it.
  • Timely
  • Clear: Ambiguous expressions free.
  • Flexible: More than one decision and more than one user.
  • Verifiable: Multiple users, equal decision.

An information system is the set of functions, processes, and data that make an organization or that are designed to perform.

Automated Information System (CIS)

An SI does not need to exist, be mandatory based on the use of computers. The SI is always present, mechanized or not.

The application of computers to SI produces information systems or computer-based Automated Information Systems (CIS).

Positive Effects of Computerized Systems

  • Information processing speed.
  • Accuracy of calculations.
  • Easy to handle large volumes of information.
  • Storage capacity.
  • Quality of presentation of results.
  • Reducing long-term costs.
  • Quick information to make decisions.
  • Allows users to share information.

Negative Effects of Computerized Systems

  • High initial costs.
  • Dependence of system performance.
  • Rapid obsolescence of hardware and software.
  • Automation Staff.
  • Requires training and expertise.
  • Susceptibility to viruses.
  • Staff resistance to change.
  • Wastage Equipment.

Transactional Information Systems

Significant achievements of labor, because they automate operational tasks of the organization.

They are gatherers of information due to the intense input and output information.

These systems are responsible for integrating a large amount of information handled in the organization.

Its cost is easily justified to the overall direction because its benefits are visible and palpable.

They are easily adaptable to application packages which are in the market.

Management Information System

They provide end-user management, information products that support most of their needs for routine decision-making.

EIS Executive Information Systems (GSS)

Management information systems tailored to the strategic information needs of senior management.

  • The goal is to provide senior management with immediate access and easy access to selective information on key factors that are critical to achieving strategic objectives of an enterprise.

How are the elements of the hardware?

  • Processor
  • Main Memory
  • Input Devices
  • Output Devices
  • Secondary Storage Devices

Processor Consisting of two elements:

  • Arithmetic-Logic Unit (UAL): Run the arithmetic and logical operations with data.
  • Control Unit (CU): Managing the computer resources. Direct the flow of data to the UAL.

Main Memory Types:

  1. ROM (Read-Only Memory)
  2. RAM (Random Access Memory)

The BIOS (Basic Input/Output System)

In personal computers, the firmware is responsible for loading the operating system of the computer and checking the hardware components available.

Cache Memory

You can reside in two locations:

  • Within the CPU (L1 Cache)
  • Between the CPU and RAM (L2 Cache)

Why is the ROM called firmware?

Because it results from the integration of hardware and software.

Types of Buses:

  • Data Bus: Set of tracks (cables) for which data or pulses travel to and from the processor. These cables connect the CPU to memory and other hardware devices.
  • Address Bus: Tracks (wires) where they travel memory addresses, which provide access to data and computer programs. These cables connect the CPU and RAM.

Classification of Software

  • Base-Software: A set of programs that enable computer resources.
  • Systems-Software: A set of programs that let you manage and control the resources of a computer.
  • Application Software
  • Software Package
  • Expert Systems
  • Artificial Intelligence

Programming languages are called the set of rules, instructions, and rules necessary by means of which human beings can relay commands to the computer. – Algara Redondo

Classification

  • High-Level Languages: They have a resemblance to the written form as human beings we communicate, so the computer is closer to man.
  • Mid-Level Languages: They have a syntax similar to the high-level languages and incorporate both directions and low-level functions allowing greater control over the hardware.
  • Low-Level Languages: Are essentially very similar to the binary code that manages the computer through a sequence of zeros and ones which are then transformed into electrical impulses.

Types

  • Machine-Language: They are built on the basis of sequences of zeros and ones.
  • Procedure-Oriented Languages: Allow writing a single statement instead of many annoying machine language instructions.
  • Object-Oriented Language: The emphasis is placed on the object that executes the action and not in the same action as in the procedure-oriented. Its hierarchical structure from top to bottom makes it easy to design and understand the programs.

Network Operating System

  • Provides basic services to computers on a network.
  • Coordinates the activities of various devices.
  • Provides customers access to network resources.
  • Permits data and device security.
  • Supports both mechanisms that allow applications to communicate with each other.
  • Is integrated with other known operating systems.

Types of Network (Type):

  • Point-to-Point
  • Client-Server

Scope of Network:

  • Local Area Network (LAN)
  • Wide Area Network (WAN)
  • Metropolitan Area Network (MAN): A network covering a metropolitan area, for example, a city or a suburban area. A MAN usually consists of one or more LANs within a common geographical area.

Network Adapter:

Receive data and convert it to electrical signals, controls the flow of data through the cable.

Network Cable:

  • Twisted Pair
  • Coaxial
  • Fiber-Optic

Network Topologies

  • Linear Topology: A bus topology uses a single backbone cable to be terminated at both ends. All hosts are connected directly to this backbone.
  • Star Topology: Connect all the cables with a central point of concentration.
  • Ring Topology: Connect a host to the next and the last host to the first. This creates a physical ring of cable.
  • Mesh Topology: Is implemented to provide maximum protection to avoid interruption of service.
  • Hybrid Topology: Star-linear, star-ring.
  • Extended Star Topology: Connecting individual stars to each other by connecting hubs or switches. This topology can extend the scope and coverage of the network.
  • Star Hierarchical Topology: Similar to an extended star. But instead of connecting hubs or switches together, the system connects to a computer that controls traffic in the topology.

Expansion or Extension of Network

  • Repeater
  • Hub
  • Bridge
  • Switch
  • Router
  • Gateways
  • Types of Remote Access Connectivity