[Day 1] 2. COSA Revision

Server

• A server is a device that provides services to clients based on a request-response model.
• Example: When you enable a mobile hotspot and connect your laptop to access the internet, your mobile acts as a server.
• Common misconceptions about servers:
  • Servers are not always high-performance devices with large storage or computational power.
  • Even a small device can be a server if it provides a service.
  • Sometimes, a client device might have better specifications than the server.

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Purpose of a Website for an Organization

• Websites help organizations achieve various goals, such as:
  • Building an online presence.
  • Sharing information and services.
  • Enhancing customer interaction and engagement.
  • Promoting products or services to a wider audience.

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Firewalls

• What is a Firewall?
  • A security system that controls incoming and outgoing network traffic.
  • Helps protect systems using public IPs from potential hacking threats.
• Types of Firewalls:
  1. Whitelisted Firewalls:
     • Deny all traffic by default and explicitly allow certain traffic.
  2. Blacklisted Firewalls:
     • Allow all traffic by default and explicitly deny certain traffic.

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Cybersecurity Reality

• There are two types of people in the world:
  1. Those who know they've been hacked.
  2. Those who don’t know they’ve been hacked yet.

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Windows Server Editions

• Editions: Essential, Standard, and Datacenter.
• Trial Period: These operating systems come with a trial period of 180 days.

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Website Hosting Requirements

Example: Hosting a website like helloditiss.com

1. Domain Name Registration:

   • A domain name (e.g., helloditiss.com) is registered through organizations like ICANN (Internet Corporation for Assigned Names and Numbers).
   • Without a domain name, users must remember the website's IP address to access it.
   • A Record: Used in DNS (Domain Name System) for forward lookup, mapping the domain name to the IP address of the web server.

2. Public Static IP Address:

   • Required for the website to be accessible globally.
   • Why static?
     • If the IP changes, the DNS A record must be updated every time, causing inconvenience.

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Archive.org

• Use archive.org to see how websites looked in the past.
• Once information is on the internet, it’s nearly impossible to erase it completely.

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