Week_5_-_Networks_and_Cloud_Computing

Network Fundamentals

• Computer Network: A system connecting two or more computers for communication.

  • Network Nodes: Devices and computers within the network.

• Networks facilitate sharing of hardware, software, and databases among users.

Network Topology

Definition

• Network Topology: Physical or logical arrangement of devices on a network.

Common Types

• Star Topology: Devices connect to a central hub.

• Bus Topology: All devices connect to a single backbone line.

• Mesh Topology: Multiple connections among devices to ensure network resilience.

Network Types

Categories

• Personal Area Network (PAN): Connects devices close to a single user.

• Local Area Network (LAN): Connects devices in a limited area, like an office or home.

• Metropolitan Area Network (MAN): Covers larger areas like a city or campus.

• Wide Area Network (WAN): Connects devices over large geographic areas, often through leased telecom links.

Client/Server Systems

• Client/Server Architecture: Dedicated services for tasks like database management.

  • Clients request services; servers fulfill these requests with specified data.

Channel Bandwidth

• Channel Bandwidth: Data exchange rate, typically measured in bits/sec.

• Broadband Communications: High-speed data transmission.

Communications Media

Categories

• Guided (Wired) Media: Signals transmitted through physical means (e.g., cables).

• Wireless Media: Signals broadcast over airwaves (radio, microwave).

Guided Media Types

• Twisted-pair Wire: Basic, cost-effective, but limited in speed.

• Coaxial Cable: Better for data transmission, but more expensive.

• Fiber-optic Cable: Premium bandwidth with minimal distortion, expensive to install.

Wireless Technologies

• NFC: Short-range communication for consumer devices.

• Bluetooth: Connects multiple device types wirelessly.

• Wi-Fi: Uses radio signals for wireless data transmission across networks.

Communications Hardware

Common Devices

• Modem: Converts digital data for transmission.

• Fax Modem: Combines functionalities of fax and modem.

• Multiplexer: Allows multiple signals over one medium.

• Bridge: Connects similar networks (LAN-to-LAN).

• Router: Directs data packets between networks.

• Gateway: Entry point for connecting different networks.

Communications Software

Types

• Network Operating System (NOS): Manages network devices (e.g., Linux, Windows Server).

• Network Management Software: Safeguards software from illegal actions.

• Mobile Device Management (MDM): Manages mobile device settings and security remotely.

• Software-Defined Networking (SDN): Programmable control of networking without extensive physical access.

The Internet and World Wide Web

Growth Overview

• Internet users are continuously increasing globally.

Key Features

• The Internet connects devices internationally.

• Influences global politics and user interactions.

• ARPANET: The precursor to the Internet established by the U.S. Department of Defense in 1969.

• IP Protocol: System governing message routing between computers.

How the Internet Works

• Internet Backbone: Main high-speed communication lines.

• IP Address: Unique identifier for computers on the Internet.

• Routing: The process of sending data across networks.

Accessing the Internet

Connection Methods

• LAN Server: For organizations managing local networks.

• Internet Service Providers (ISP): Facilitate Internet access with accounts and necessary software/devices.

• Dial-up: Standard option using telephone lines.

• Broadband: Cable, DSL, satellite, and wireless connections are common today.

How the Web Works

• Web Browsers: Clients that access and display web pages.

• HTML: Standard language defining the structure of web pages.

• CSS: Defines the visual presentation of content in web pages.

Web Programming Languages

Key Languages

• JavaScript: For interactive web functionality.

• Java: An object-oriented programming language for web applets.

Web Services and Development

• Standards and Tools: Facilitate Web service communication.

• Amazon Web Services (AWS): A comprehensive service platform for online catalog access.

• Tools: Software like Adobe Dreamweaver aids in web page creation.

Internet and Web Applications

Web 2.0

• Social networking and user interaction platforms.

Applications

• Provides real-time news, educational resources, job information, and online communications.

Online Media

• Involves streaming and downloaded entertainment content.

Intranets and Extranets

• Intranet: An internal network for an organization.

• Extranet: Links an intranet with external partners via web standards.

• VPN: Secure connection method for accessing resources remotely.

The Internet of Things (IoT)

Overview

• A network of physical objects with sensors for data exchange.

Applications

• Usage spans various industries: agriculture, manufacturing, traffic monitoring, etc.

Cloud Computing

Definition and Benefits

• Software and storage accessed via the Internet.

Service Models

• Public Cloud: Shared infrastructure provided by third-party services.

• Private Cloud: Dedicated infrastructure for a single organization.

• Hybrid Cloud: Combination of public and private cloud services.

Autonomic Computing

• Systems managing themselves to adapt and self-optimize in computing environments.

Summary

• Networks are crucial for achieving organizational objectives in the digital landscape of the Internet and the World Wide Web, with IoT creating opportunities for data analysis and cloud computing providing cost-effective IT solutions.