Networking Today: Module 1 Notes

Module Objectives

  • Module Title: Networking Today
  • Module Objective: Explain the advances in modern technologies.
    • Networks Affect our Lives: Explain how networks affect our daily lives.
    • Network Components: Explain how host and network devices are used.
    • Network Representations and Topologies: Explain network representations and how they are used in network topologies.
    • Common Types of Networks: Compare the characteristics of common types of networks.
    • Internet Connections: Explain how LANs and WANs interconnect to the internet.
    • Reliable Networks: Describe the four basic requirements of a reliable network.
    • Network Trends: Explain how trends such as BYOD, online collaboration, video, and cloud computing are changing the way we interact.
    • Network Security: Identify some basic security threats and solutions for all networks.
    • The IT Professional: Explain employment opportunities in the networking field.

Network Components

  • Hosts: Every computer on a network is called a host or end device.

    • Servers: Provide information to end devices. Examples include:
    • Email Servers: Manage and deliver emails to client devices.
    • Web Servers: Host websites and serve web pages.
    • File Servers: Store files that can be accessed by clients.
    • Clients: Send requests to servers to retrieve information.

  • Client-Server Model:

    • Dedicated servers run server software while clients use client software to access resources provided by servers.
    • Both roles can exist in peer-to-peer networks, where devices can act as both clients and servers (recommended for very small networks).
    • Advantages: Easy to set up, lower cost; Disadvantages: No centralized management, less secure.

  • End Devices: Origin of messages where data flows from and to.

  • Intermediary Devices: These include switches, routers, and firewalls. Their roles include:

    • Regenerating data signals.
    • Providing path information.
    • Notifying devices of communication failures.

  • Network Media:

    • Metal Wires: Use electrical impulses for communication.
    • Fiber-Optic Cables: Utilize light pulses for data transfer.
    • Wireless Transmission: Employs electromagnetic waves for data transfer.

Network Representations and Topologies

  • Topology Diagrams:
    • Physical Topology: Shows physical layout of devices and cabling.
    • Logical Topology: Illustrates the data flow, devices, ports, and addressing schemes.

Common Types of Networks

  • Types of Networks:

    • Home Networks: Connecting a few devices.
    • Small Office/Home Office (SOHO) Networks: Remote offices connecting to a corporate network.
    • Medium to Large Networks: Hundreds/thousands of interconnected computers.
    • The Internet: A vast network connecting millions of devices globally.

  • LANs vs WANs:

    • Local Area Networks (LANs): Cover a small geographical area; administered by one organization.
    • Wide Area Networks (WANs): Span large geographical areas; interconnect multiple LANs through service providers.

  • Internet and Extranets: The Internet connects LANs/WANs and is maintained by organizations like IETF and ICANN. An intranet is an internal network for an organization; an extranet provides access to authorized external parties.

Internet Connections

  • Home/Small Office Connections:

    • Cable: High bandwidth from cable providers.
    • DSL: High bandwidth over telephone lines.
    • Cellular: Leverages cell phone networks.
    • Satellite: Beneficial in rural areas.
    • Dial-up: Low bandwidth, inexpensive.

  • Corporate Connections:

    • Dedicated Leased Lines: Reserved circuits for private networking.
    • Ethernet WAN: Extends LAN technology into WAN applications.
    • Business DSL: Various formats for higher business requirements.

Reliable Networks

  • Network Architecture: Technologies that support data movement across the network. Key characteristics include:
    • Fault Tolerance: Reducing failure impact via redundancy and multiple paths.
    • Scalability: Ability to expand without performance degradation.
    • Quality of Service (QoS): Ensures reliable delivery of content, especially for voice and video data; requires proper configuration to avoid bandwidth issues.
    • Security: Protects data integrity, confidentiality, and availability against various threats.

Network Trends

  • Technology Trends:
    • Bring Your Own Device (BYOD): Users access resources via personal devices.
    • Online Collaboration: Tools like Cisco WebEx enable remote teamwork.
    • Video Communication: Video conferencing enhances communication capabilities.
    • Cloud Computing: Allows data storage and application access over the internet, facilitated by data centers.

Network Security

  • Security Threats: Include viruses, internal misuse, and data breaches. Effective security involves multiple layers:
    • Home/Small Office: Antivirus software, firewalls.
    • Larger Networks: Dedicated firewalls, intrusion prevention systems (IPS), and Virtual Private Networks (VPNs) for enhanced security.

The IT Professional

  • CCNA Certification: Validates foundational technologies and necessary skills in networking.
  • Job Opportunities: Resources available through NetAcad for finding networking careers, emphasizing the demand for relevant skills.