Computer Networks Overview

Networks Affect Our Lives

• Networks are important for communication and connect people both locally and globally.

Network Components

• A host or end device refers to any computer connected to a network.
• Wireless Internet Service Providers (WISPs) connect subscribers to specific access points or hotspots primarily found in rural areas.
• Wireless broadband is a common solution for home and small businesses using cellular technology and external antennas.

Network Representations and Topologies

• Network diagrams visually represent network connections, outlining various components and their relationships.
• Network topologies describe the physical or logical arrangement of network devices.
• Common network topologies include:
  • Bus Topology
  • Star Topology
  • Ring Topology
  • Mesh Topology

Common Types of Networks

• Networks are categorized based on the geographical area coverage, number of users, services provided, and responsibility.
• Local Area Networks (LANs) connect devices in a limited geographical area.
  • LANs are typically administered by a single entity.
  • LANs provide high-speed bandwidth for internal devices.
• Wide Area Networks (WANs) connect LANs over broader geographical regions.
  • WANs are usually managed by one or more service providers.
  • WANs generally offer slower speeds compared to LANs.
• The internet comprises a global collection of interconnected LANs and WANs.
  • LANs connect to each other through WANs.
  • The internet is not controlled by any specific individual or group.

Internet Connections

• Internet Service Providers (ISPs) provide access to the internet.
• Common internet connection types include:
  • Dialup
  • DSL
  • Cable Modem
  • Satellite
  • Fiber-optic
  • Wireless

Reliable Networks

• Reliable networks possess four fundamental requirements:
  • Availability: Ensuring network accessibility for users.
  • Reliability: Maintaining network functionality and data integrity.
  • Scalability: Adapting to changes in network size and demand.
  • Security: Safeguarding the network and its data from threats.

Network Trends

• Bring Your Own Device (BYOD) allows users to access information and communicate using their personal devices such as laptops, tablets, and smartphones.
• Online collaboration tools enable users to work together on projects remotely.
  • Collaboration tools like Cisco WebEx facilitate instant communication and interaction.
• Video communication allows for visual communication with anyone regardless of location.
  • Video calls are becoming increasingly important for effective collaboration.
• Cloud computing enables storing and retrieving data remotely on internet-based servers.
  • Applications can also be accessed via the cloud.
  • Cloud computing offers flexibility and accessibility to devices anywhere.
• Four types of cloud services exist:
  • Public cloud: accessible to the general public through a pay-per-use model.
  • Private cloud: exclusive to a specific organization or entity.
  • Hybrid cloud: combines both public and private cloud components.
  • Community cloud: shared by a group of organizations with similar requirements.

Network Security

• Network security is essential for protecting data and resources from various threats.
• Security threats can be external or internal.
  • External threats originate from external sources and include:
    • Viruses, worms, and Trojan horses
    • Spyware and adware
    • Zero-day attacks
    • Threat Actor attacks
    • Denial of service attacks
    • Data interception and theft
    • Identity theft
  • Internal threats originate within the network and include:
    • Lost or stolen devices
    • Accidental misuse by employees
    • Malicious employees
• Security solutions are crucial for mitigating threats.
  • Security solutions for home or small office networks typically include:
    • Antivirus and antispyware software
    • Firewall filtering
  • Larger networks may also employ:
    • Dedicated firewall system
    • Access control lists (ACLs)
    • Intrusion prevention systems (IPS)
    • Virtual private networks (VPNs)

The IT Professional

• Cisco Certified Network Associate (CCNA) certification demonstrates knowledge of fundamental networking technologies.
  • CCNA validates skills for adopting next-generation network technologies.
  • The new CCNA focus emphasizes:
    • IP foundation and security
    • Wireless, virtualization, automation, and network programmability
• DevNet certifications validate software development skills at associate, specialist, and professional levels.
• Specialist certifications demonstrate proficiency in job-specific roles and areas of interest.

Explore the essential components, representations, and classifications of computer networks. This quiz covers various network topologies, common types of networks, and the role of networks in communication. Test your knowledge on how networks connect people and devices both locally and globally.