Key Concepts

The classic IT infrastructure for computing is client-server model:

• Clients: Devices like your mobile phone, running a service booking app, act as clients. They send requests to access features and services online.

• Servers: These are specialised systems designed to handle multiple client requests, process them, and respond by sharing resources. A server can be a physical computer, a software or a virtual machine.

  Typically, servers are made by two elements -

• (1) CPU: Handles computation and processes client requests.

• (2) RAM: Stores temporary data to speed up processing, ensuring quick responses to clients.

• Servers often need to store and retrieve data, interacting with databases to fulfill client requests (e.g., booking an appointment). The database can run on the same server as the application or on a dedicated server, depending on the setup.

• A Database Management System (DBMS) helps to organises data in a structured way, making retrieval fast and efficient— which is crucial for real-time apps like booking services.

Hierarchy Summary:

• Devices encompass servers.

• Servers contain CPUs and RAM, hosting databases.

---

Five Characteristics of Cloud Computing

• Traditional IT infrastructure requires physical data centres house servers and networking equipment, power, and cooling systems.

• Cloud computing leverages data centres to deliver services over the internet. Networking is essential for cloud computing, enabling access to remote resources and support data centre’s communication.

Functional Example - Imagine an e-commerce website:

• A user on a device (laptop) sends a request via networking (internet) to a server in a data center. The server, using its CPU and RAM, processes the request by querying a database to retrieve product details.

• In a cloud computing scenario, the data centre is managed by a provider like AWS, and the server is a virtual instance (e.g., EC2) that scales automatically during high traffic, all accessed via networking.

Cost Comparison

Example: Streaming Music on Spotify

Think about the last time you played a song on Spotify (or any music streaming app). You picked a track, hit play, and enjoyed the music instantly. Did you realise you were using cloud computing? Probably not! Here’s how it works:

• Where’s the Music? The song isn’t stored on your phone or computer. Instead, it lives on powerful servers in a data center far away—maybe halfway across the world.

• How Do You Get It? When you press play, your device connects to those servers over the internet, and the music streams to you in real-time.

• Why Is This Cloud Computing? Cloud computing is all about accessing resources (like storage or processing power) from remote servers on-demand, without owning or managing the hardware yourself. With Spotify, you’re tapping into a massive library of music stored “in the cloud” instead of keeping it locally.

This happens so seamlessly that most of us don’t even think about the technology behind it.

An Analogy: Borrowing Books from a Library

To make this even clearer, let’s use an analogy. Imagine cloud computing is like visiting a library instead of buying every book you want to read:

• In the Past: If you wanted a book, you’d have to buy it, store it on your shelf, and maintain it (dust it off, fix torn pages, etc.). That’s like owning your own server to store music or data—expensive and time-consuming.

• With the Library (Cloud): You walk into the library, borrow the book you need, read it, and return it. You don’t own the book or worry about shelf space—you just use it when you want. Spotify is your digital library: the music is there when you need it, stored and managed by someone else, and you access it with a simple “membership” (your subscription or even a free account).

Just like borrowing a book, streaming music relies on someone else’s resources (servers in the cloud) rather than your own, making it convenient and efficient.

Benefits of Cloud Computing

Let us look at the value proposition of AWS Cloud, and related benefits of cloud computing.

Reference:

https://docs.aws.amazon.com/whitepapers/latest/aws-overview/six-advantages-of-cloud-computing.html

1. Economic Scale: AWS buy computing resources in bulk and maximised its resource utilisation to ensure the infrastructure is more efficiently and at a lower cost. By sharing these savings, AWS helps customers reduce their own IT expenses, as they don’t need to buy expensive machines or build a data centre for initial set up.

   • Why it matters:

     • Cost Savings: Lots of people use AWS, the cost of running everything gets split up, making it cheaper and less work for everyone.

2. Global Infrastructure: AWS has 100+ availability zones in 30+ regions.

   • Why it matters:

     • Great availability/reliability: By running applications closer to users around the world, it reduces delays (latency). The resources across different availability zones ensures that applications remain responsive even if one zone experiences outage while continues to detect and distribute the traffic to healthy instances to minimise downtime.

     • High agility: Enables businesses to expand quickly into new markets by deploying apps fast in different regions. Plus, by choosing where their data is stored, customers can meet local laws and regulations more easily.

3. Elasticity & Scalability: scale up or down easily based on the demand - can easily handle increased load by adding resources (e.g., servers, storage)

---

Stay Connected

Enjoyed this post? Follow me for more easy tech explainers!

• Instagram: @the5ththought

• X: @the5ththought

Acknowledgments

This blog reflects my own learning journey, pulling together ideas from various online articles, tutorials, and hands‑on practice. Thanks to the wider tech community for all the shared knowledge!