Skip to content

What is Cloud Computing?

The Client and the Server

Let's start with how the exchange between a user and website, which is fundamentally just a server, works.

graph LR
  A[🧑‍💻 User] -----> B((Internet)) -----> C[ Server ];
  C --> B;
  B --> A;

A user on his device be it a laptop, tablette or a mobile phone, tries to access a page on a website i.e. a server. For them to find each other, the user and the server, on the network they need to have IP addresses. The server's IP address allows the user to know where on the network is the server to which he wants to send a request. And the Client's IP server allows the server to know who requested what and where to send the data requested.

A more detail version of the exchange between a client, the user with his device, and the server:

graph LR
    A[Client IP: 192.168.1.100] -->|HTTP Request| B((Internet))
    B -->|DNS Lookup| C[DNS Server]
    C -->|Returns IP| B
    B -->|Forward Request| D[Web Server IP: 203.0.113.10]
    D -->|HTTP Response| B
    B -->|Return Data| A

    style A fill:#f9f,stroke:#333
    style D fill:#bbf,stroke:#333

Lets breakdown the exchange:

  • First, your browser sends an HTTP request to a domain (e.g., google.com).
  • The DNS server translates the domain to the server's IP (like 203.0.113.10)
  • The Request travels through internet routers to reach server
  • The Server processes request and sends response
  • The Response returns through internet to your device

The IP addresses work like postal addresses for the internet, enabling two-way communication between client and server.

The DNS server works like a phone book that allows us to find the physical address thanks to the name, the URL (e.g. google.com).

What is a Server?

A server is a computer or a device that provides resources, data, or services to other computers or devices, known as clients, over a network. Servers are designed to handle requests from multiple clients simultaneously and are typically more powerful than standard desktop computers in terms of processing power, memory, and storage capacity.

A Server is composed of several parts: CPU, RAM, Storage, Network Interface, Power Supply.

graph TD
    A[CPU] -->|Processes| B[RAM]
    B -->|Stores in| C[Storage/HDD]
    A -->|Manages| D[Network Card]
    E[Power Supply] -->|Powers| A
    E -->|Powers| B
    E -->|Powers| C
    E -->|Powers| D

    style A fill:#f96,stroke:#333
    style B fill:#9cf,stroke:#333
    style C fill:#9f9,stroke:#333
    style D fill:#f9f,stroke:#333
    style E fill:#ff9,stroke:#333

To know more about servers

Having a server is useful to allow users to access whatever you have to offer them, but it comes with few drawbacks.

Drawbacks of owning a server

  • You need a place to keep it, you will need to pay a rent or pay for the electricity.
  • Replacing hardware takes time and might be costly, which limits the scalability of your server.
  • You will require a team be able to monitor the infrastructure 24/7/
  • And if there is a disaster you loose everything.