Computer Networking and Programming Concepts

Technology in Action - Chapter 7: Networking: Connecting Computing Devices

• Chapter 7 of Technology in Action, 16th Edition, covers networking, focusing on connecting computing devices.
• Learning objectives include describing computer networks and their pros/cons, explaining network definition methods, defining transmission media, detailing network hardware, describing necessary software, summing available broadband internet options, and summarizing wireless internet access. Additionally, learning objectives are presented for setting up home networks, troubleshooting wireless issues, and securing wireless home networks.
• A computer network connects two or more computers to enable communication. Each connected device is called a node. Nodes can be computers, peripherals (printers, game consoles), or network devices (routers).
• Network benefits include sharing high-speed internet, printers, devices, and facilitating common communications.
• Networks have a disadvantage in setup and administrative time.

Learning Objectives (detailed)

• 7.1: Describe computer networks and their advantages and disadvantages.
• 7.2: Explain different ways networks are defined (by distance, administration, or protocols).
• 7.3: Outline the different types of transmission media used in networks (wired and wireless).
• 7.4: Detail the hardware necessary for a network (network adapter, NIC, modem, router, switch).
• 7.5: Describe the software necessary for networks.
• 7.6: Summarize broadband internet access options (cable, DSL, fiber-optic).
• 7.7: Summarize how to access the internet wirelessly.
• 7.8: Explain factors to consider before creating a home network.
• 7.9: Explain the process of setting up a home network.
• 7.10: Describe potential problems with wireless networks and solutions.
• 7.11: Describe how to secure a wireless home network.

Networking Fundamentals (Objective 7.1)

• Computer networks connect two or more computers to enable communication with each other.
• Each device on a network is a node, which can be a computer, peripheral, or network device.
• Networks offer advantages such as sharing Internet access, printers, and files.
• The main disadvantage of a network is its setup time and administration.

Networking Fundamentals (Benefits of Networks)

• Sharing high-speed Internet connections
• Sharing printers and peripheral devices.
• Sharing files.
• Common communications.

Networking Fundamentals (Disadvantages of Networks)

• Setup and administration.

Networking Fundamentals (How data moves)

• Data transfer rate (bandwidth) is the maximum speed data can be transmitted.
• Throughput is the actual speed data is transferred.
• Data transfer rate and throughput are generally measured in Mbps or Gbps.

Network Architectures (Objective 7.2)

• Networks can be classified by distance (PAN, LAN, HAN, MAN, WAN), levels of administration (client/server, peer-to-peer), and protocols (Ethernet, Wi-Fi, GbE).

Network Components (Objective 7.3)

• Networks require a method of connecting nodes (cables, wireless technology).
• Hardware (like network adapters and routers) enable communication and data transfer.
• Software controls and enables network operation.
• Transmission media can be wireless or wired and establish communication channels between network nodes.

Network Components—Wired (Objective 7.3)

• UTP cable: Twisted copper wires surrounded by a plastic jacket.
• Coaxial cable: Single copper wire surrounded by layers of plastic.
• Fiber-optic cable: Plastic or glass fibers.

Network Components—Hardware (Objective 7.4)

• Network adapter (NIC): An integrated adapter.
• Modem translates broadband signals to digital.
• Router transfers packets between networks.
• Switch is like a network traffic signal. Data packets are sent in bundles called packets.

Network Components—Software (Objective 7.5)

• Operating systems support peer-to-peer networks or client/server communication.

Connecting to the Internet (Broadband, Objective 7.6)

• Broadband (cable, DSL, or fiber-optic) is the preferred internet access method.
• ISPs provide Internet access.
• Households may also opt for Cellular or Dial-up access.

Connecting to the Internet (Wireless, Objective 7.7)

• Wireless internet is increasingly accessed when away from home networks.
• Mobile hotspots and wireless ISPS offer such connection methods.
• Data plans are required for sustained internet access.

Installing and Configuring Home Networks (Objectives 7.8 & 7.9)

• Planning your home network involves considering connected devices.
• Using the most current standards and equipment helps with performance.
• Routers and switches are key to device connectivity.

Installing and Configuring Home Networks—Specialized Devices

• NAS devices provide centralized storage and access for network data.
• Home network servers share files across the network.
• Network-ready devices are connected directly to the network (wired or wireless).

Installing and Configuring Home Networks—Troubleshooting Problems

• Wireless Network problems stem from interference (walls, large metal objects).
• Placement of access points influences signal strength.
• Wireless range extenders help amplify Wi-Fi signals.

Managing and Securing Wireless Networks (Objectives 7.10 & 7.11).

• Using encryption and security protocols protects wireless networks.
• Changing SSIDs reduces vulnerability.
• Disabling SSID broadcast makes data more secure.
• Changing default passwords and creating complex passphrases improve security.
• Implementing media access controls, limiting signal range, keeping router firmware updated, and disabling remote access further enhance security.

Chapter 9: Securing Your System: Protecting Your Digital Data and Devices

• Cybercrime includes FBI-related scams, identity theft, etc.
• Malware is software with malicious intent.
• Types of malware include Adware, Spyware, and Keystroke Loggers.
• Spam is unwanted email/software.
• Cookies are small text files received when you visit a website (they don't invade your privacy.)

Identity Theft and Hackers (Objectives 9.1 & 9.2)

• Cybercrime is any criminal action done using computers, networks, or the internet.
• Cybercriminals exploit computers, networks, and the internet to commit crimes, and may use four categories: FBI-related scams, identity theft, nonauction fraud, and advance-fee fraud.
• Hackers are individuals who violate the security of a computer system for various purposes, which fall into different categories: white-hat (ethical hackers), black-hat (illegal activity), and grey-hat (selling services for illegal access).
• Trojan horses give the appearance of useful software but actually run malicious code, while backdoor programs and rootkits allow hackers to gain access to a system.
• Packet analyzers (sniffers) examine data packets, while keyloggers record user input.

Identity Theft and Hackers (Zombies and Botnets)

• A zombie is a computer under a hacker's control; often used in denial-of-service attacks.
• When many zombies act in coordination against a target system, it's known as a botnet.
  • DDoS Attacks (Distributed Denial of Service) utilize botnets to overwhelm a target with malicious requests, causing it to shut down.

Identity Theft and Hackers (Exploit Kits)

• Exploit kits are malicious programs run on servers, searching for security vulnerabilities in other computer systems.

Computer Viruses (Objective 9.3 & 9.4)

• Viruses are programs that attach to other programs to spread to other computers. Their goal is to replicate themselves and copy code to as many host files as possible.
• Examples of virus types include boot sector, logic bombs, and time bombs, worms, script/macro viruses, email viruses, and encryption viruses.

Computer Viruses (Types of Viruses)

• Boot-sector viruses replicate themselves onto a hard drive's master boot record.
• Logic Bombs are triggered when conditions are met (opening a file, running a program, or after a time), or time bombs rely on passage of time.
• Worms are self-replicating and do not need host file execution.
• Script/macro viruses are written as a series of commands; they execute without user intervention.
• Email viruses spread by using address books in mail systems.
• Encryption viruses (ransomware) encrypt files and demand payment to release decryption keys.

Computer Viruses (Detection Avoidance)

• Polymorphic viruses change their code,
• Multi-partite viruses attack multiple file types,
• Stealth viruses conceal themselves (temporarily deleting their code or hiding in active memory).

Online Annoyances and Social Engineering (Objective 9.5)

• Spyware (unwanted software) automatically downloads with other software and runs in the background. It can use cookies to track information.
• Adware displays sponsored advertisements.
• Malware is any software with malicious intent.
• Keystroke loggers record keystrokes for illegal use.
• Spam is unwanted or junk email.

Online Annoyances and Social Engineering (Social Engineering)(Objective 9.6).

• Social engineering, using social skills, is any technique to lure individuals to reveal sensitive information.
• Pretexting creates a legitimate-sounding scenario to prompt such information.
• Phishing involves luring users to reveal personal information.
• Pharming involves planting malicious code.

Protecting Data: Firewalls (Objective 9.7)

• Firewalls (software or hardware) protect computers from hackers.
• They filter out unwanted packets sent to specific ports; and can block certain ports entirely.

Protecting Data: Antivirus (Objective 9.8)

• Antivirus software is designed to detect and prevent virus infection.

Protecting Data: Antivirus techniques:

• Virus signatures are unique portions of virus code.
• Quarantining is placing viruses in a secure location, so they don't damage other files.
• Inoculation records key attributes about files on a computer to help with identification.

Preventing Virus Infections (Objective 9.8)

• Drive-by downloads exploit system weaknesses by downloading viruses onto a computer. Keeping operating systems updated prevents this.

Authentication: Passwords and Biometrics (Objective 9.9)

• Strong passwords should be at least eight characters long and include uppercase/lowercase letters, numbers, and symbols.
• Biometrics include fingerprint, iris pattern, voice authentication and face recognition.

Chapter 10: Behind the Scenes: Software Programming

• Programming converts a task into commands that a computer can execute.

Life Cycle of an Information System (Objective 10.1)

• Careers in programming offer various advantages including job opportunities, strong salary, and remote work options.
• Programming is necessary when a task doesn't already have corresponding existing software.
• Macros can condense complex sequences that otherwise would take multiple steps into a single command.

Life Cycle of an Information System—System Development Life Cycle (Objective 10.2).

• An Information System is a collection of pieces working together to accomplish a shared goal and comprises People, Procedures, Data, Hardware, and Software.
• The System Development Life Cycle (SDLC) is a process for developing information systems, typically involving six steps. a. Problem and opportunity identification, b. Analysis through program specifications, c. Systems design (data flow diagrams), d. System development, e. Testing and installation f. Maintenance and evaluation

Life Cycle of a Program: Problem Statement (Objective 10.4)

• The problem statement clearly describes tasks, highlights programming goals, and helps programmers interact with users about the task, data (the initial input), intended outputs, and necessary steps.

Life Cycle of a Program: Algorithm Development (Objective 10.5)

• Algorithms are step-by-step instructions for a program to complete a given task.
• Flowcharts visually represent algorithm steps and patterns, utilizing symbols like rectangles, ovals, and diamonds to show program flow and decisions.
• Pseudocode is a text-based approach to documenting algorithms.

Life Cycle of a Program: Coding (Objective 10.6)

• Converting an algorithm to machine instructions (CPU instructions) is called coding.
• Programmers use programming languages (with special words or strict rules) to control the CPU, without needing detailed knowledge of its hardware. Different generations of languages exist.

Life Cycle of a Program: Coding—Portability (Objective 10.6)

• Portability means a program will run on different types of computer systems.
• Variables hold inputs and outputs.
• Comments explain sections of code.

Life Cycle of a Program: Coding—Compilation (Objective 10.6)

• Compilation translates code into machine language (binary or 1s and 0s).
• Interpreters translate code line by line.

Life Cycle of a Program: Coding—IDE (Objective 10.6)

• IDEs (Integrated Development Environments) are tools that ease code writing and testing.

Life Cycle of a Program: Debugging (Objective 10.7)

• Debugging involves identifying and clearing errors in a program.
• A testing plan shows the expected input values and resulting output for various conditions. Logical errors happen when a program runs but produces the wrong result; while runtime errors arise during execution of the program.

Life Cycle of a Program: Testing and Documentation (Objective 10.8).

• Internal testing is done within the developing team.
• External testing includes evaluation by users.
• Beta testing assesses software before release.
• Release to Manufacturers (RTM) signifies the product's readiness to be released to vendors/clients.
• Documentation describes the program.
• General Availability (GA) marks the product's release and availability for the public.

Many Programming Languages (Objective 10.9)

• Several programming languages are in demand. Programming languages, like C/C++ and Java, are popular in various industries.
• Introductory courses in programming include topics such as design, algorithm development, debugging techniques, and project management.

Many Programming Languages—Selecting the Right Language: (Objective 10.10)

• Programming teams consider factors such as available space, speed requirements, organizational resources, and the target application type when choosing a language.
• Visual languages (like Scratch and App Inventor) use graphical blocks representing elements/variables for easy program creation.

Exploring Programming Languages (Objective 10.11)

• Java and C# are languages often used for collecting information from networked computers. These languages are considered architecture neutral. Objective-C and Swift are often used to program applications on Apple products.

Chapter 11: Behind the Scenes: Databases and Information Systems

• Databases are collections of related data that can be stored, organized, sorted, and queried (accessed).
• Database advantages include efficient data management, information sharing, and data integrity. Data integrity ensures accurate and reliable data.

Database Types—Flat Databases (Objective 11.2)

• Flat databases store data in a simple table format, and can lead to redundancy, inconsistency, or inappropriate/incomplete data.

Database Types—Relational Databases (Objective 11.3)

• Relational databases organize data into tables with relationships between them.
• Common fields (i.e., primary/foreign keys) link data across multiple tables. Relationships can be one-to-many, one-to-one or many-to-many.

Using Databases—Components & Functions (Objective 11.7).

• DBMS (Database Management Systems) are software allowing a computer to manage database functions. Main functions include:
• Storing and defining database data.
• Viewing, adding, deleting, and modifying data.
• Querying (extracting) data.
• Outputting (displaying/printing reports).

Using Databases—Data Types (Objective 11.7).

• Data types categorize data (Short/Long text, Number/Large number/Currency, Date/Time, Yes/No, Calculated fields, OLE object, Hyperlink).

Using Databases—Field Properties (Objective 11.7).

• Field properties define aspects such as field size, default values, and captions.

Using Databases—Inputting & Managing Data (Objective 11.8).

• Input forms are used to control how new data enters a system by using various checks, like Range checks, field constraints, completeness checks, consistency checks, and alpha or numeric checks. Data validation is the process of using these checks to prevent incorrect data from entering the database.

Using Databases—Viewing & Sorting (Objective 11.8)

• Data viewing & sorting enable reordering and display of data.

Using Databases—Extracting/Querying (Objective 11.8).

• Extracting data from databases involves using queries or filters to retrieve specific data meeting particular criteria.

Using Databases—Outputting Data (Objective 11.8).

• Outputting data from databases can be through displaying or printing a report. It can be transferred to another program/application.

Data Warehousing and Data Mining (Objective 11.10)

• Data mining is the process of analyzing data to identify patterns and trends (such as analyzing customer behaviors).

Data Warehousing and Storage—Data Mining Techniques

• Techniques utilized in data mining include anomaly detection and identification, association/affinity groupings, classification, clustering, estimation, and visualization.

Test your knowledge of fundamental concepts in computer networking and programming. This quiz covers algorithms, object-oriented programming features, network types, and security threats. Perfect for students in computer science or IT courses.