Cloud Computing and Computer Networks Fundamentals

Posted on Sep 22, 2025 in Communications Electronic Engineering

Cloud Computing Fundamentals

Cloud computing is a technology enabling users to access and store data, applications, and services over the Internet, rather than on a local computer or server. It provides on-demand computing resources such as servers, storage, databases, networking, and software.

Key Concepts of Cloud Computing

  • On-Demand Service: Resources like storage, processing power, and software are available whenever needed.
  • Internet-Based Access: All cloud services are accessed through the internet using devices like mobile phones and laptops.
  • Resource Pooling: Multiple users share the same physical resources while their data and tasks remain separate.
  • Scalability: Cloud services can be scaled up or down based on user requirements.
  • Pay-as-you-go Model: Users pay only for what they use, similar to utility bills.
  • Multi-Tenancy: A single cloud infrastructure is securely shared by multiple customers.
  • Automatic Updates: Software and security updates are managed by cloud service providers without user intervention.

Benefits of Cloud Computing

  • Cost-effective: Eliminates the need for heavy infrastructure and maintenance.
  • Flexible: Access from anywhere, anytime.
  • Reliable: Strong backup and disaster recovery features.
  • Efficient: Faster deployment and performance of applications and services.

Common Examples of Cloud Services

  • Google Drive: Cloud storage.
  • Dropbox: File sharing and backup.
  • Microsoft Azure / AWS: Cloud platforms for hosting applications and websites.

Computer Network Basics

A computer network is a group of two or more interconnected computers that share resources, data, applications, and services. Connections can be wired or wireless, enabling communication between devices.

Key Components of a Computer Network

  • Nodes (Devices): Computers, smartphones, printers, etc., connected to the network.
  • Transmission Media: The medium used for data transfer, such as cables (wired) or radio signals (wireless).
  • Network Interface Card (NIC): Hardware connecting a device to the network.
  • Switches and Hubs: Devices connecting multiple computers within a local network.
  • Routers: Devices connecting different networks, often linking a LAN to the internet.
  • Protocols: Sets of rules defining data transmission (e.g., TCP/IP).

Types of Computer Networks

  • LAN (Local Area Network): Covers a small area like a home, office, or school. It is fast and inexpensive.
  • MAN (Metropolitan Area Network): Covers a city or town. It is larger than a LAN and slower.
  • WAN (Wide Area Network): Covers a large geographical area; the internet is the largest example.

Basic Network Topologies

  • Bus Topology: All devices connected to a single cable.
  • Star Topology: All devices connected to a central hub.
  • Ring Topology: Each device connected to two others in a circular path.
  • Mesh Topology: Every device connected to every other device.

Importance of Networks

  • Resource Sharing: Enables sharing of printers, files, and internet access.
  • Communication: Facilitates emails, messages, and calls.
  • Data Security & Backup: Provides centralized control over data and security.
  • Cost Efficiency: Reduces costs through resource sharing.

Concept of Distributed Systems

A distributed system is a collection of independent computers that work together, appearing as a single system to users. These computers are networked and coordinate actions by sharing resources and communicating.

Key Features of Distributed Systems

  • Multiple Independent Systems: Consists of multiple computers (nodes or hosts) performing different tasks.
  • Transparency: Users perceive a single system, even though tasks are spread across many machines.
  • Resource Sharing: Hardware (printers, storage) and software (databases, applications) are shared across the system.
  • Scalability: Easy to add more systems to handle increased load or users.
  • Fault Tolerance: If one system fails, others can continue operating, enhancing reliability.
  • Concurrency: Multiple processes can run simultaneously on different machines.

Examples of Distributed Systems

  • Google Search Engine: Runs on thousands of distributed servers.
  • Cloud Computing Platforms: Such as AWS, Azure, Google Cloud.
  • Online Banking Systems: Data is securely shared across many branches.
  • Social Media Platforms: Handle millions of users via distributed servers.

Advantages of Distributed Systems

  • Improved performance and speed.
  • Higher reliability and fault tolerance.
  • Better resource utilization.
  • Easier expansion and maintenance.

Challenges of Distributed Systems

  • Complex to design and manage.
  • Data consistency issues.
  • Security risks.
  • Network dependency.

Cloud Infrastructure

Cloud infrastructure refers to the physical and virtual resources supporting cloud computing services. This includes servers, storage, networking, virtualization software, and data centers that enable cloud platforms.

Main Components of Cloud Infrastructure

  • Compute (Servers): Physical or virtual machines (VMs) performing processing tasks and handling applications, data, and services.
  • Storage: Cloud storage systems like block, file, and object storage (e.g., Amazon S3, Google Cloud Storage) for files, databases, and backups.
  • Networking: Includes routers, switches, firewalls, and load balancers, enabling communication between servers and users over the internet.
  • Virtualization: Technology allowing multiple virtual machines on a single physical machine, improving resource utilization and scalability.
  • Management and Monitoring Tools: Tools for monitoring usage, performance, billing, and automation (e.g., dashboards, APIs).
  • Data Centers: Physical locations housing servers and hardware for running cloud services.

Types of Cloud Infrastructure Services

  • IaaS (Infrastructure as a Service): Provides virtualized hardware over the internet. Examples: Amazon EC2, Google Compute Engine.
  • PaaS (Platform as a Service): Offers a platform and tools for application development. Examples: Google App Engine, Microsoft Azure App Services.
  • SaaS (Software as a Service): Delivers ready-to-use software over the internet. Examples: Gmail, Google Docs, Microsoft Office 365.

Advantages of Cloud Infrastructure

  • Scalable and flexible.
  • Cost-effective (pay-as-you-go).
  • Easy to manage and maintain.
  • High performance and availability.
  • Secure and reliable.

Pros and Cons of Cloud Computing

Cloud computing is widely adopted in IT, education, business, and daily life due to its flexibility and low cost. However, it presents both advantages and disadvantages.

Pros of Cloud Computing

  • Cost-Effective: No need to purchase expensive hardware or software; pay only for usage.
  • Scalability: Easily adjust resources based on demand, ideal for growing businesses.
  • Accessibility: Access data and applications from anywhere via the internet, supporting remote work and global collaboration.
  • Automatic Updates: Providers manage updates, backups, and security patches.
  • Disaster Recovery and Backup: Regular data backups and easy recovery after loss or failure.
  • Environmentally Friendly: Optimizes server usage and reduces energy waste.

Cons of Cloud Computing

  • Internet Dependency: Requires a stable internet connection; no access during network failures.
  • Data Security & Privacy: Storing sensitive data on cloud servers carries security risks if not adequately protected.
  • Limited Control: Users rely on the provider for system management and customization.
  • Downtime: Provider outages or technical issues can affect service access.
  • Hidden Costs: Unexpected charges may arise from usage or storage over time.
  • Vendor Lock-in: Difficulty switching providers due to compatibility issues.

Cloud Delivery Models

Cloud delivery models define how cloud services are provided. Each model offers different levels of control, flexibility, and management. The three main models are IaaS, PaaS, and SaaS.

1. Infrastructure as a Service (IaaS)

  • Definition: Provides basic IT resources like virtual machines, storage, and networking over the internet.
  • Users: IT administrators and developers seeking full infrastructure control.
  • Examples: Amazon EC2, Microsoft Azure VM, Google Compute Engine.
  • Benefits: High flexibility and control, scalable infrastructure, pay only for used resources.

2. Platform as a Service (PaaS)

  • Definition: Offers a development environment with tools, libraries, and infrastructure for building and deploying applications.
  • Users: Developers and programmers.
  • Examples: Google App Engine, Microsoft Azure App Services, Heroku.
  • Benefits: No need to manage hardware or OS, faster application development, automatic updates and scalability.

3. Software as a Service (SaaS)

  • Definition: Provides ready-to-use software applications over the internet.
  • Users: End-users who utilize software directly without installation or maintenance concerns.
  • Examples: Gmail, Google Docs, Microsoft Office 365, Dropbox.
  • Benefits: Accessible from any internet-connected device, no installation required, automatic maintenance and upgrades.