Day 1 of devops

Working of internet diagram

🚀 Networking Basics Explained for Everyone

1. IP Address 🏠 – The Digital Home Address

Think of an IP Address like the home address of your computer or mobile phone on the internet.

✅ Simple Example:
When you order pizza, you give your home address so the delivery person knows where to go.
Similarly, when you browse YouTube, your IP address tells YouTube where to send the videos.

✅ Types:

• IPv4: Like 192.168.1.10 (most common)

• IPv6: Like 2001:abcd:… (for future internet, more advanced)

💡 In DevOps: You need IP addresses to connect servers, websites, and apps.

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2. Public vs Private IP 🌍🏠 – Internet vs Home Address

Imagine you have two types of addresses:

• 🌍 Public IP: Your official address that anyone (even outside your city) can use to contact you.

• 🏠 Private IP: Like your flat number inside your apartment building, only used within your building.

✅ Real-Life Example:

• Public IP → Pizza delivery guy can find your main building.

• Private IP → Once inside, the security guard uses your flat number to direct them to your door.

💡 In DevOps:

• Servers with public IP can be accessed from anywhere 🌍.

• Servers with private IP are protected, used inside secure networks 🏠.

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3. DNS (Domain Name System) 🔠➡️🏠 – The Phonebook of the Internet

You don’t memorize your friends' phone numbers anymore—you just save their names in your phone 📱.

✅ DNS is like the Internet’s Phonebook:

• You type www.netflix.com → DNS finds the real IP address (like 13.227.80.55) and connects you.

✅ Example:

• You: “Call Mom” → Phone looks up number.

• You: “Open Netflix” → DNS finds the server’s IP.

💡 In DevOps: DNS connects your website name (like yourbusiness.com) to the correct server 🖥️.

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4. Subnet 🧱 – Rooms Inside a Building

If your office building 🏢 is your network, then subnets are like different rooms or sections inside it:

• Marketing Team in Room A,

• IT Team in Room B,

• Sales Team in Room C.

✅ Why Use Subnets?

• 🛡️ Security: Only authorized people can enter specific rooms.

• 🛜 Organization: Easier to manage groups within one big building.

💡 In DevOps: Subnets keep servers organized and safe—like public websites in one room and secure databases in another.

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5. CIDR (Classless Inter-Domain Routing) 🎫 – Group Tickets for Network Seats

Think of CIDR like grouping seats in a movie theatre 🎫.

✅ Example:

• “Row A, Seats 1-20” means 20 seats are reserved together.

• CIDR like /24 means 256 IP addresses grouped together.

✅ Why It’s Cool?

• 🎟️ Easier ticketing (network management).

• 🛡️ Access control: You can allow or block big groups of devices at once.

💡 In DevOps: CIDR blocks help you manage large groups of devices or servers easily.

🚀 Networking Basics Part 2

6. Routing 🚗🗺️ – Google Maps for Your Data

Routing is like Google Maps but for your internet traffic!

✅ Simple Example:
Imagine you want to go to a coffee shop ☕:

• Google Maps finds the best route, sometimes via the highway, sometimes via shortcuts.

✅ With Computers:

• When your computer sends data to a website, routers decide the best route through the internet to get it there.

💡 In DevOps: You set up routing tables so your servers know how to talk to each other or reach the outside world.

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7. Firewall 🔥🛑 – Security Guard for Your Network

Think of a firewall like a bouncer at a club 🎶:

• It allows good people in and blocks troublemakers from entering.

✅ Example:

• You let friends in 🟢 but block strangers 🚫.

• Similarly, a firewall allows certain traffic (like website visitors) and blocks dangerous traffic (like hackers).

💡 In DevOps:

• AWS has Security Groups, Azure has NSGs (Network Security Groups)—both are firewalls for your servers.

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8. Load Balancer ⚖️ – Traffic Police Officer

A Load Balancer is like a traffic police officer 🚦 at a busy junction:

• When cars (visitors) come in, it directs them to less crowded roads (servers), so traffic flows smoothly.

✅ Example:

• Netflix gets millions of visitors. A load balancer spreads them across many servers, so no one server crashes.

💡 In DevOps:

• Helps websites and apps handle lots of users without downtime.

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9. VPC (Virtual Private Cloud) 🏰 – Your Private Internet Castle

A VPC is like your own private castle 🏰 in the big internet world 🌍.

✅ Example:

• You decide who can enter, who stays inside, and who can leave.

• Inside the VPC you have rooms (subnets), guards (firewalls), and rules (routes).

💡 In DevOps:

• AWS → VPC

• Azure → Virtual Network (VNet)

• GCP → VPC Network
  VPC helps you build safe, private spaces for your apps on cloud.

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10. VPN (Virtual Private Network) 🕵️‍♂️🔒 – Secret Tunnel to Your Office

A VPN is like a secret tunnel 🛣️ between your home and office.

✅ Example:

• You work remotely 👨‍💻, but use a VPN to safely access office servers as if you were sitting inside the office.

✅ Why VPN?

• 🛡️ Keeps data private.

• 🕵️‍♂️ Hides your real location.

• 🚀 Securely connects on-premise servers to cloud.

💡 In DevOps: Companies use VPNs to securely connect employees to internal tools or connect offices to cloud servers.

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11. NAT (Network Address Translation) 🎭 – Mask for Your Home Network

NAT is like a mask 🎭 your home uses to talk to the internet.

✅ Simple Example:

• In your house 🏠, multiple people (phones, laptops) use one public WiFi connection (one public IP) to browse the internet.

• NAT makes it look like all devices are one person talking to the outside world.

✅ Why?

• 🛡️ Security: People on the internet don’t see your personal devices directly.

• 🛜 Saves IPs: You don’t need a unique IP for every device.

💡 In DevOps: NAT Gateways allow servers in private subnets to access the internet safely without exposing themselves.

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12. Proxy Server 🪞 – Your Internet Middleman

A Proxy is like a middleman 🧑‍💼 who talks to websites on your behalf.

✅ Example:

• Instead of you calling the pizza shop 🍕, your assistant (proxy) calls, places the order, and brings it back.

✅ Why Use Proxies?

• 🛡️ Privacy: Hide your real identity.

• 🚀 Faster Browsing: Stores frequently accessed data.

• 🏢 Office Control: Companies use proxies to block certain websites.

💡 In DevOps:

• Forward Proxy → hides your requests.

• Reverse Proxy → hides your servers (Nginx, HAProxy).

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13. Ports 🚪 – Doors for Communication

Think of a port like a door 🚪 on your computer where specific conversations happen.

✅ Simple Example:

• Door 80 → 📃 websites (HTTP).

• Door 443 → 🔐 secure websites (HTTPS).

• Door 22 → 🖥️ remote login (SSH).

✅ Why It’s Useful:

• You can control which doors are open or closed on your server (extra safety!).

💡 In DevOps: You’ll configure which ports are open on cloud servers to allow or block traffic.

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14. OSI Model 🏗️ – The 7-Layer Cake of the Internet

The OSI Model is like a 7-layer cake 🎂 showing how data moves from your device to the internet.

✅ Simple Breakdown:

💡 In DevOps: You mostly focus on Layer 3–7, ensuring your services communicate properly.

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15. TCP vs UDP 📩⚡ – Reliable Mail vs Fast Postcards

✅ TCP (Reliable Mail 📩):

• Like courier delivery with tracking & delivery guarantee.

• Slower but reliable (e.g., banking websites, login systems).

✅ UDP (Fast Postcard ⚡):

• Like a postcard: fast but no tracking.

• Great for speedy tasks like video streaming, gaming, live chat.

💡 In DevOps: You decide which protocol to use based on whether you need speed or reliability.

Here’s the final part of the networking terms (16–20), explained in easy, non-technical language with examples and emojis so anyone can understand! 🚀

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16. Ingress & Egress 🚪⬅️➡️ – Entry and Exit Doors of Your Server

✅ Ingress = Incoming traffic (🚪⬅️)
✅ Egress = Outgoing traffic (🚪➡️)

✅ Simple Example:

• Ingress is like people entering your house (visitors knocking on your door).

• Egress is you leaving your house to go shopping.

✅ In Servers:

• Ingress → When users visit your website.

• Egress → When your server connects to the internet (e.g., downloading updates).

💡 In DevOps: You manage ingress and egress rules to control who can talk to your servers.

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17. SSL/TLS 🔒 – Secret Handshake for the Internet

✅ SSL/TLS is like a secret handshake 🤝 between you and a website.

✅ Example:

• Imagine you're sharing private messages with a friend 📨. You both use a special handshake to know it’s really each other, and encrypt messages so others can’t read them.

✅ Why It’s Important:

• 🛡️ Keeps data safe from hackers.

• 🔐 HTTPS uses SSL/TLS → websites with a lock symbol 🔒 are secure.

💡 In DevOps: You set up SSL certificates to make websites secure and trusted.

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18. Network Tools 🧰 – DevOps Toolbox

✅ Some network tools you’ll often use in DevOps jobs:

✅ Example:

• Think of these like plumbing tools 🧰—each tool fixes or optimizes a specific network-related problem.

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19. Ping & Traceroute 🏓📍 – Checking Internet Health

✅ Ping → Like a ping pong ball 🏓, you send a quick “hello” to a server and see how fast it responds.

✅ Traceroute → Like following a Google Maps route 📍, it shows the path your data takes to reach a server.

✅ Example:

• Ping tells you: “Is this website alive?”

• Traceroute tells you: “Which cities (routers) does my data travel through?”

💡 In DevOps: Helps check server health and network problems.

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20. Bandwidth vs Latency 🚀🐢 – Speed vs Delay

✅ Bandwidth (Speed 🚀) → How much data you can transfer at once.
✅ Latency (Delay 🐢) → How quickly the data starts moving.

✅ Example:

• 🛣️ Bandwidth = Size of the highway (more lanes = more cars at once).

• 🕰️ Latency = Traffic light speed (how soon cars start moving).

💡 In DevOps: You monitor both so websites run fast and smooth.

Source i followed for this is https://www.youtube.com/watch?v=mNTs-shuFno