CompTIA Network+ and MIS Comprehensive Notes
Module 1: Introduction to Networking
- Instructor: Jill West
- Book: CompTIA Network+ Guide to Networks, Ninth Edition. © 2022 Cengage. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.
Icebreaker: Interview Simulation
- Students pair up to interview each other on interesting or unusual facts.
- Each pair introduces one another to the class with a relevant story connected to the course topics.
Module Objectives
By the end of this module, you should be able to:
- Distinguish between peer-to-peer and client-server networks
- Identify types of applications and protocols used on a network
- Describe various networking hardware devices and the most common physical topologies
- Describe the seven layers of the OSI model
- Explain best practices for safety when working with networks and computers
- Describe the seven-step troubleshooting model for troubleshooting network problems
Network Models
- A computer network is defined as a collection of interconnected computing devices (nodes) such as computers, servers, and printers that exchange data and share resources.
- Networks can be either wired (using Ethernet or fiber optic cables) or wireless (using Wi-Fi).
- They enable communication, internet access, and file sharing, from small home networks to the global Internet.
Network Models & Topology
- Topology: Refers to how different parts of a network are arranged.
- Physical Topology: Relates to the network's hardware layout (e.g., cables, devices).
- Logical Topology: Describes how data flows within the network and how software controls access.
- Network Operating System (NOS): Essential for client-server models, facilitating access to the network.
Client-Server Network Model
- Resources are managed by the NOS via a centralized directory database.
- Windows Domain: A logical group of computers managed by a Windows Server.
- Active Directory (AD): Centralized directory database containing user account details and security information.
- Users can access resources from any computer on the network managed by Active Directory Domain Services (AD DS).
- A computer requesting data or services is termed a client.
Responsibilities of the NOS
- Managing client data and resources - Ensuring authorized user access
- Controlling user file access
- Restricting network access
- Dictating communication rules
- Supplying applications and data to clients
Requirements for Servers
- Need more memory, processing power, and storage capacity
- Generally equipped with special hardware for network management functions
Client-Server Applications
- Network Services: Applications and data resources available to users.
- Example: A web browser (client application) requests a web page from a web server (server application), and the server returns the requested data.
Peer-to-Peer Network Model
- In peer-to-peer (P2P) networks, each computer's OS controls access to its resources without centralized control.
- Nodes or Hosts: Each computer acts independently within the logical group.
Advantages and Disadvantages of P2P
- Advantages:
- Simple configuration
- Less expensive to set up
- Disadvantages:
- Not scalable
- Security issues
- Not suitable for large installations
Network Services & Their Protocols
- Protocols: Defined as methods and rules governing communication between devices on a network.
- Two primary network protocols:
- TCP (Transmission Control Protocol)
- IP (Internet Protocol)
Examples of Client-Server Applications
- Web services
- Email services
- DNS services
- FTP services
- Database services
- Remote access services
Knowledge Check (Activity 1-1)
- Question: Which protocol could not be used to access a server in a nearby building?
- Options: Telnet, RDP, TLS, SSH
- Answer: c. TLS (Transport Layer Security) does not provide remote access, only encryption underlying other protocols.
Network Hardware
- LAN (Local Area Network): Typically covers a small area and includes components such as computers, printers, and switches, often using a star topology.
- Switch: Receives incoming data from ports and redirects it to intended destinations.
Key Concepts of Switches
- NIC (Network Interface Card): A network port for devices to connect to a network; also called a network adapter.
- A LAN may contain multiple switches. A backbone connects network segments.
Role of Routers
- Routers manage traffic between multiple networks.
- Can determine the best path for traffic to travel between networks.
- SOHO (Small Office/Home Office) networks: Use routers to connect to the internet.
- Industrial-Grade Routers: May include multiple ports for various networks.
Comparison: Routers vs. Switches
- A router connects different local networks (acting as a gateway), whereas a switch operates within a local network only.
MANs and WANs
- WAN (Wide Area Network): Connects multiple LANs over broader geographic areas.
- MAN (Metropolitan Area Network): Connects LANs within a specific geographic area, sometimes referred to as a campus area network (CAN).
- PAN (Personal Area Network): Represents local device networks like smartphones and computers.
- Notable types of networks:
- BAN (Body Area Network)
- SAN (Storage Area Network)
- WLAN (Wireless Local Area Network)
The Seven-Layer OSI Model
- Purpose: Describes how hardware, software, and protocols interact during communication.
- Layer 7: Application Layer: Interfaces applications on different devices.
- Layer 6: Presentation Layer: Responsible for data reformatting and encryption.
- Layer 5: Session Layer: Manages sessions, including synchronization and recovery of data.
- Layer 4: Transport Layer: Responsible for transferring application payloads. Uses two protocols:
- TCP: Connection-oriented, checks for data receipt.
- UDP: Connectionless, does not check for receipt.
- Layer 3: Network Layer: Moves messages between nodes, primarily uses IP.
- Layer 2: Data Link Layer: Interfaces with physical hardware. Data Link Layer messages are called frames.
- Layer 1: Physical Layer: Sends raw bit streams over physical medium. Data is transmitted as voltage, light, or wavelengths.
Protocol Data Unit (PDU)
- Defined as a group of bits as they move through the OSI layers.
Knowledge Check (Activity 1-2)
- Question: Which OSI layer adds both header and trailer?
- Options: Transport layer, Network layer, Data Link layer, Physical layer
- Answer: c. Data Link Layer.
Safety Procedures and Policies
- Technicians must know safety procedures to protect themselves and components.
Emergency Procedures
- Familiarize with emergency exits and fire suppression systems.
- Use portable fire extinguishers and understand security measures during system failures.
Safety Best Practices
- Electrical and Tool Safety: Adhere to OSHA guidelines.
- Lifting Heavy Objects: Maintain proper posture and techniques.
- Static Electricity Precautions: Ground yourself and protect against ESD (Electrostatic Discharge).
Troubleshooting Network Problems
Seven-Step Troubleshooting Model
- Identify the problem and its symptoms.
- Establish a probable cause theory.
- Test the theory to determine the cause.
- Create a problem resolution plan.
- Implement the solution or escalate.
- Verify functionality; implement preventative measures.
- Document findings and actions.
Summary of Module 1
- You should now be able to distinguish between P2P and Client-Server networks, identify applications and protocols, describe networking hardware types and topologies, understand the OSI model layers, explain safety best practices, and execute the troubleshooting model.
Module 2: Infrastructure and Documentation
Module Objectives
By the end of this module, you should be able to:
- Describe roles of various network and cabling equipment in commercial settings.
- Maintain network documentation.
- Manage network changes.
Structured Cabling
- Follow ANSI/TIA-568 standard aiming for optimal media installation to maximize performance.
- The structured cabling hierarchy is built on a star topology for networking.
From Demarc to Workstation
- Entrance Facility (EF): Where the network connects to the organization.
- Demarc Point: Where the service provider's network meets the organization's network.
- MDF (Main Distribution Frame): Central connection point for LAN or WAN.
- Data Room: Holds networking equipment.
- Rack Systems: Platforms for organizing network equipment; available in various configurations.
Cabling Types
- Patch Cable: Short run with connectors for immediate connection.
- Horizontal Cabling: Connects workstations to the nearest data room.
- Backbone Cabling: Connects network segments.
- Quality cable installation is critical for reducing network problems.
Cable Management
- Proper techniques for termination and management are vital for network functionality.
- Pay attention to grounding and electromagnetic interference (EMI) when routing cables.
Monitoring Environment and Security
- Data rooms include HVAC systems to control temperature and humidity.
- Access should be restricted to authorized IT personnel for security.
Network Documentation Importance
- Ensures efficient communication and speeds up troubleshooting with updated documentation.
Network Diagrams
- Graphical representations for physical and logical layouts of the network; essential for planning and changes.
Change Management
- Manage system changes with thorough planning and documentation to prevent disruptions.
Summary of Module 2
- You should be able to describe infrastructure roles, maintain documentation, and manage changes within networks.
Module 5: Cabling
Module Objectives
By the end of this module, you should be able to:
- Explain basic data transmission concepts.
- Describe physical characteristics and standards for cabling types.
- Compare benefits and limitations of various media.
- Select and use the appropriate tools for troubleshooting cable issues.
Transmission Basics
- Frequency: Measured in MHz or GHz; indicates electrical signal changes.
- Bandwidth: Data theoretically transmitted over time.
- Throughput: Actual data transmitted over time.
Transmission Flaws
- Noise disrupts signal integrity; sources include EMI and cross-talk.
- Attenuation: Signal strength loss as it travels.
- Latency: Delay between signal transmission and receipt affecting performance.
Duplex Communication
- Full-Duplex: Signals travel in both directions simultaneously.
- Half-Duplex: Signals travel in both directions but only one direction at a time.
- Simplex: Signals travel in only one direction.
Multiplexing
- Technique allowing multiple signals through a single medium using multiplexers and demultiplexers.
- Types include Time Division Multiplexing (TDM), Frequency Division Multiplexing (FDM), and their optical equivalents (WDM).
Types of Cables
- Coaxial Cable: Used in networks, structured with an inner conductor, insulation, shielding, and sheath.
- Twinaxial Cable: Similar to coax but features two conducting cores for higher throughput.
- Twisted-Pair Cable: Composed of color-coded pairs; common in Ethernet networks categorized by cable type (e.g., Cat 3, Cat 5e).
Cable Management and Best Practices
- Follow defined standards for cable pinouts and ensure proper terminations for effective communication.
Knowledge Check (Activity 5-1)
- Question: What is the typical maximum segment length for Ethernet networks?
- Answer: 100 meters.
Fiber-Optic Characteristics
- Advantages include high throughput, noise resistance, and security.
- Fiber types: Single-Mode Fiber (SMF) and Multimode Fiber (MMF), with differing core diameters and optimal uses.
Troubleshooting Tools
- Tools include continuity testers, multimeters, and cable performance testers for effective diagnosis and corrections of signaling issues.
Summary of Module 5
- Consolidate knowledge of transmission concepts, cabling characteristics, comparison between networking media, and solutions for troubleshooting cable problems.
Module 2: Computers and Their Business Applications
Module Objectives
By the end of this module, you should be able to:
- Define a computer system and its components.
- Discuss the history of computer hardware and software.
- Analyze the impact of computing power factors.
- Summarize basic computer operations.
- Discuss types of input, output, and memory devices.
- Discuss computers in business applications.
- Explain major types of software applications.
- List the generations of programming languages.
- Define object-oriented programming.
Defining a Computer
- Computer Definition: A machine that accepts data, processes it, and outputs information.
- Instructions: Programs written in a machine-understandable language.
Components of a Computer System
- Main Memory: Stores data and instructions.
- CPU (Central Processing Unit): Composed of:
- ALU (Arithmetic Logic Unit): Executes arithmetic operations.
- Control Unit: Directs operations.
- Buses: Link devices, classified as internal (e.g., video cards) and external (e.g., USB).
- Processor Types: Single, Multi-core (dual, quad, hexa, octa-core).
Computer History
- Major advancements over the last 80 years.
- Evolution from silicon-based technology to gallium arsenide and carbon nanotubes for improved performance.
Factors Impacting Computing Power
- Speed: Measured in fractions of seconds (milliseconds to picoseconds).
- Accuracy: Digital systems exceed human error handling.
- Storage and Retrieval Capabilities: Bits as the fundamental unit; understanding binary encoding and ASCII.
Storage Area Networks and NAS
- SAN (Storage Area Network): Dedicated high-speed networks for managing shared storage devices.
- NAS (Network-Attached Storage): Provides file-based data storage services to other devices.
Classifications of Computers
- Types: Classified by cost, memory, speed, and sophistication including mainframes, supercomputers, servers, and personal computers.
- Top Supercomputers: List including Fugaku and Summit.
Software Overview
- Types of Software: System vs. Application software with control programs managing hardware resources.
- Commercial software examples: Word processors, spreadsheets.
Programming Languages
- Generations: Ranging from Machine languages (1GL) to High-level languages (4GL) and AI technologies (5GL).
- Popular languages: Python, Java, JavaScript among others.
Object-Oriented Programming
- Concepts involving classes, objects, and modular design lead to effective problem-solving and code reuse.
Summary of Module 2
- You should now be able to define computer systems, understand their components, analyze their historical impact, and articulate software usages in business applications.