WGU C182 Introduction to IT

Information Technology

The technology used in creating, maintaining, and making information accessible.

IT Professional Roles

Administration and Support

System Administrator

Maintains all aspects of the system including hardware, software, and programming.

Network Administrator

In charge of all aspects of the computer network

Database Administrator

Focuses on the design, development, and support of database management systems (DBMSs).

Security Administrator

Installs, configures, and administers firewall security to protect systems and proactively work to stop intrusions.

Web Administrator

Installs, configures, maintains, secures, and troubleshoots web severs.

Support IT Professionals

Help desk and training.

Information

Processed data.

DIKW Hierarchy

Defines the transition of data to information to knowledge to wisdom. (Data Information Knowledge Wisdom)

Data in DIKW

The input directly received by the user (or computer). It is generally not usable until it has been converted into a relevant form.

Information in DIKW

Having been inferred from data; one or more processes have been applied to the data to transform it into a more useful form.

Knowledge in DIKW

Information that has been put to use; information placed into a context. Refined information such that the user of the knowledge is able to call forth only relevant portions of information when needed.

Wisdom in DIKW

Provides a social setting to knowledge; an understanding of the "why". Can only come by having both knowledge and experience.

Information Systems

A collection of data and information used to support the management of an organization. Also refers to the technical components and human resources that enable the assembly, storage, and processing of data and the delivery of information. This has existed for a lot longer than computers.

Characteristics of Quality Data

Relevance - the data being used must apply directly to the decision being made

Timely - data must be efficient and must be provided in a timely manner

Thorough - the data must be complete

Accurate - data should be captured only once, where possible and should be captured as close to the point of activity as possible.

Reliable - data should reflect stable and consistent data collection processes across collections points and over time

IPOS

The Input-Procession-Output-Storage Cycle

Input

Raw data is entered by the user.

Processing

Raw data is organized or structured for usefulness.

Output

Information is output so user can see results.

Storage

Processed information is stored for permanent record.

Computer System

A collection of components that work together to meet the needs of the user; typically categorized as either hardware, software, networks, or users.

Hardware

Physical components of a computer system which include the system unit and its components and peripheral devices; tangible aspects of the computer.

Software

Computer programs that tell the computer what to do--how to execute commands and process information

Network

A collection of computers and resources connected by various media so that they can communicate with each other.

User

Those who use a computer.

Software Categories

Systems Software and Applications Software

Evolution of Users

First users were the engineers who built and programmed computers, then employees who had received specialized training were users, and now today, anyone and everyone can be a user.

Protocol

Rules provided by which networks communicate with each other.

TCP/IP

Transmission Control Protocol/Internet Protocol. Most commonly used protocol; is required of all computers that communicate over the Internet.

Protocol Stack

A collection of protocols. TCP/IP is an example.

Components of a Computer

CPU, Memory and Storage, Peripheral Devices

CPU

Executes programs' instructions and commands various components in the computer. Referred to as the "chip".

Memory

Stores the programs being executed and the data they are using.

I/O Subsystem

All peripheral devices where long term storage devices are used.

Bus

Permits information to move between each component; electrical channels that enable communication among the electronic components

System Unit

Critical component of all computer based systems; consists of most of the hardware the computer needs in order to run; comes in a variety of shapes and sizes.

Internal Components of the System Unit

Case, Internal Bays, Buses, Ports, Hard Drive, Motherboard, CPU, CPU Cooler, Memory Module (RAM), Power Supply Unit (PSU), Expansion Slots/Cards

Parts of the CPU

Control Unit (CU) - retrieves the instructions and the raw data that is input and coordinates or controls the sending of those instructions and data to the ALU

Arithmetic Logic Unit (ALU) - does the actual processing of the data; completing mathematical calculations and logical operations to process the data and converting the input of the keyboard text entry to output displayed on the screen

System Clock

Controls the speed at which instructions are processed.

RAM

Stands for Random Access Memory.

It temporarily stores data before it is processed and sent to your screen or printer.

It is volatile (means data or information stored disappears when the computer is turned off or loses power).

You can choose the amount of RAM your computer has.

Types of RAM

Dynamic RAM (DRAM) - typically called main memory

Static RAM (SRAM) - cache memory and registers

BIOS ROM

BIOS stands for Basic Input Output System; ROM stands for Read Only Memory.

Typically stored in ROM chip on the motherboard.

Is software not hardware, ("basic" operating system that runs when the computer is first turned on).

Runs tests of memory and the CPU and initializes hardware components so that the actual Operating System can be loaded from the hard disk.

Can't choose the amount or contents.

1st Generation of Computers

Vacuum tubes, relay switches, the need to program in machine language

2nd Generation of Computers

Transistor components, magnetic core memory, smaller size, easier to program, disk drives and drums, called mainframe computers

3rd Generation of Computers

Silicon chips (known as ICs - integrated circuits), reduced cost, called mini computers, networks introduced via dumb terminals

4th Generation of Computers

Single chip processor, called microcomputer, first personal computer, rudimentary computer graphics, home use

Moore's Law

Doubling of transistor count roughly every 18 - 24 months (exponential increase); observation, not physical law

Evolution of Storage

Punch cards, magnetic tape, hard disks, floppy disks, optical discs, flash memory, cloud storage

Machine/Low-level Language

Written for a specific machine by the engineers who built and ran the computers; no need for OS since only one program could run at a time

Assembly Language

Easier than machine but still required detailed, precise low level instructions

Language Translator Programs

Function is to translate one program language into another; take source code and convert it to another form; source code by itself cannot be read by a computer

Complier

Improve language translator; requires that the components of the software all be defined before compilation can begin; code is more effcient

Structured Programming

Programmer is limited to high level control constructs such as while loops, for loops, and if/else statements and not allowed to use primitive GOTO statements

Object Oriented Programming

Initially introduced in Smalltalk in 1970's and early 80's

Interpreted Code

Runs inside a special environment; is better for testing

Shell Scripting

Small programs that place Linux commands or DOS batch files into a file

Local Computer

The computer that the user is using; physically present with

Remote Computer

A computer being accessed over the network

Network Hub

Connects multiple computers together; broadcasts the transmission, sending the data to every device in the network

Network Switch

More functional than a hub; records and recognizes the local network addresses (MAC or IP) or all computers connected to it

Router

Connects multiple networks together; can be used to directly connect computers to a network; will relay messages to computers with appropriate IP addresses

Wireless Access Point

Can be connected to hub, switch, or router; many routers now also act as a wireless access point; sends out a wireless signal so computers on the network can connect without a cable

Circuit Switched Network

Requires that a full pathway, or circuit, be est. before transmission can begin and maintained during the entire transmission

Packet Switched Network

A message's pathway is only est. as it is sent; the choice of pathway is based on availability and amount of message traffic

Workstations

Creates and maintains client network connections to remote servers

Virtual Machine (VM)

A software emulator program that permits a computer user to use multiple computers and multiple platforms without the expense of purchasing multiple computers; allows a user to run software for different OS platform in their computer that would not otherwise be able to run that software; this allows multiple users on a network to access the software to support collaboration.

Server

Computers that have greater hard disk storage, faster response time and are used to respond to request from other computers on the network

Client-server Network

Contains one or more servers; client is a computer that will request information from another computer; server is a computer that takes requests and responds with the requested information; the software used facilitates communication with remote servers

File Server

Sends files over the network at the request of clients.

Responds over LAN, within one location/site.

Support both application software and data files.

Web Server

Stores data files (web pages) and programs (scripts).

Responds from anywhere on the Internet.

Database Server

Responds to queries by pulling from the database.

Typically only to local clients.

Print Server

Monitors print jobs

Mail Server

Two email servers communicate with each other

FTP Server

Like web server or file server in that requests are for files and responses are the files

Point-to-Point Network

Link between two resources.

Simplest for of a network.

Limits how devices can communicate with each other

Bus Network

Devices connected along a single cable.

Size of network is restricted.

Star Network

Each device is connected to a central devices such as a hub or switch.

Ring Network

Each device is connected directly to its neighbors, and messages are forwarded from device to device until the proper destination is reached.

Mesh Network

Every device is connected directly to every other device in the network.

Domain Name Server (DNS)

Used to translate from an IP alias to an IP address

Parts of URL (Uniform Resource Locator)

Protocol, Domain name, Resource/Filename

Domain Name

Identifies the server on which the web page can be found

Domain Name Parts

Top level domain (TLD) name and Host name

Host Name

Identifies the organization that is responsible for the information on the page or provides the server space where the information is stored

TLD(Top Level Domain) Name

Always ends with a period and a three or two letter extension which signifies the type of organization or country associated with the page

Resource/Filename ID

Indicates the name of the file you are accessing, or the location of the document on the server

CIA

Confidentiality, Integrity, Availability

Confidentiality

Requires that data bet kept secure so that they are not accidentally provided or obtained by unauthorized users

Integrity

Requires that data is correct

Availability

Requires that information is available when needed

Data Integrity Efforts

1st - Must include a component that ensures the accuracy of the collected data

2nd - Must be entered into the system accurately

3rd - Data modification must be tracked

Strategic Risk Analysis

1. Identify the organization's information assets

2. Identify vulnerabilities of each asset

3. Determine threats

4. Prioritizing risks

5. Develop and enact policies that will reduce threats

Information Security Classifications

Public - available through public sources; includes names and addresses

Sensitive - not considered a threat to a person's privacy if others learn of it; include email addresses

Private - information that could be a threat if disclosed to others; includes social security and credit card numbers

Confidential - information that an organization will keep secret; includes patentable information and business plans

Defense in Depth

Protecting every layer that surrounds data

Phishing

Emails to people to redirect them to a website to perform some operation but the website is a fake and just takes the information

SQL Injection

An attacker issues a SQL command to a web server as part of the URL or as input to a form on a company's website; web server might pass the command onto the database which then allows potentially anything to be done to the database

Buffer Overflow

Placing malicious code into the buffer so that it can be executed once stored in memory; oldest and most well known software exploit; software engineers can protect against this when writing code

Hacking

When an individual obtains unauthorized access to a host

White Hat Hacker

Informs companies of potential problems with software so companies can fix