IP Address Asliyat Mein Kya Hai?
IP (Internet Protocol) Address internet ki duniya ka Aadhaar Card ya Passport
hai. Bina iske aap internet par ek message bhi nahi bhej sakte.
Jab aap Google.com kholte hain, to aapka computer Google ke IP address par request bhejta hai, aur Google wapas
aapke IP address par result bhejta hai.
1. IPv4 vs IPv6 (Internet ka Evolution)
IPv4 (The Old Standard)
Ye 32-bit ka number hota hai. (Ex: 192.168.1.1).
Problem ye hai ki duniya mein sirf 4.3 Billion IPv4 addresses the, jo ab khatam ho chuke
hain.
IPv6 (The Future)
Ye 128-bit ka lamba address hai. (Ex: 2001:0db8:85a3...).
Ye itne zyada hain ki agar dharti ke har insaan ko 1 crore IP bhi de dein, tab bhi ye khatam nahi honge.
Yaad rakhne layak cheezein: IPv4 “dots” wali hoti hai (4 numbers), IPv6 “hex + colon” wali (long address). Future mein IPv6 normal hoga, lekin abhi bhi bahut saare networks IPv4 + NAT par chal rahe hain.
2. IP Address vs MAC Address (Confusing?)
Bahut log in dono mein confuse hote hain. Is example se samjhein:
- MAC Address (Physical Address): Ye aapke device ka Fingerprint hai. Ye kabhi change nahi hota (Manufacturing ke time fix hota hai).
- IP Address (Logical Address): Ye aapki Location hai. Jaise hi aap Delhi se Mumbai jayenge, aapki IP badal jayegi, lekin MAC same rahega.
Simple Rule
MAC = LAN ke andar device identify karne ke liye. IP = Network/Internet par routing ke liye.
Real-life Example
Courier: Building Address (IP) tak parcel aata hai, phir Flat Number/Nameplate (MAC/Local) se correct ghar tak pahunchta hai.
3. Public vs Private IP (NAT Concept)
Sochiye ek Building hai (Aapka Ghar) jisme bahut saare Apartments hain (Mobile, Laptop, TV).
Public IP (Building Gate)
Ye aapke Router ko milti hai (ISP se). Poori duniya aapko isi IP se pehchanti hai. Hacker ko yahi dikhti hai.
Private IP (Flat Number)
Ye Router aapke devices ko deta hai. (Ex: 192.168.1.5). Ye internet par kisi ko nahi dikhti,
sirf ghar ke andar kaam karti hai.
Note: Ek technology hoti hai NAT (Network Address Translation). Ye aapki Private request ko Public IP mein badal kar internet par bhejti hai.
Port (Chhota but Powerful Concept)
Internet par sirf IP hi nahi, Port bhi hota hai. Example: https mostly
443 port use karta hai. NAT “ports” ka use karke multiple devices ko ek hi Public IP share karwa
deta hai.
Port Forwarding (Danger + Useful)
Agar aap home server/camera chalate ho to port forwarding hota hai. Lekin galat setting se device internet par expose ho sakta hai. Isliye UPnP bina samjhe ON mat rakho.
4. Static vs Dynamic IP (DHCP)
Kya aapne notice kiya hai ki Router restart karne par IP badal jati hai?
- Dynamic IP: Ye temporary hoti hai. DHCP Server (jo Router ke andar hota hai) devices ko rent par IP deta hai. Restart karne par nayi IP milti hai. (Normal users ke liye).
- Static IP: Ye fix rehti hai. Iske liye ISP ko extra paise dene padte hain. (Servers aur Cameras ke liye use hoti hai).
5. Subnet Mask & CIDR (Basics, No Fear)
Aapne kabhi dekha hoga: 192.168.1.15 ke saath 255.255.255.0 ya /24 likha
hota hai.
Ye batata hai ki “ghar ka network” kitna bada hai.
Subnet Mask kya karta hai?
Ye decide karta hai ki IP ka kaunsa part Network hai aur kaunsa part Device (Host).
CIDR ka matlab
/24 ka simple meaning: same network mein generally 256 addresses (approx)
possible. Home routers mein mostly 192.168.1.x/24 common hai.
6. Reserved IP Ranges (Jo Internet par “real address” nahi)
Kuch IP ranges special hoti hain. Inka kaam internet par “public identity” banna nahi hota.
- Private IPv4:
10.0.0.0/8,172.16.0.0/12,192.168.0.0/16(Home/Office ke andar) - Loopback:
127.0.0.1(Aapka computer khud se baat karta hai) - Link‑local (APIPA):
169.254.x.x(Jab DHCP se IP nahi milti)
7. IP aapko milti kaise hai? (ISP, Router, Mobile Network)
Public IP mostly ISP deta hai (Fiber/DSL/4G/5G). Phir aapka router DHCP se ghar ke devices ko Private IP distribute karta hai.
CGNAT (Carrier‑Grade NAT)
Kai ISPs ek Public IP ko multiple customers ke saath share karwate hain (IPv4 shortage ki wajah se). Is case mein “true public IP” aapke router par nahi hota.
Iska impact kya?
Port forwarding/gaming servers/remote camera access kabhi‑kabhi problem kar sakta hai. Solution: ISP se Static/Public IP ya IPv6 support.
⚠️ Hacker IP se kya kar sakta hai?
Log darte hain ki "Mera IP leak ho gaya, phone hack ho jayega". Sach ye hai:
- ✅ Wo aapki Approximate Location (City/Area) dekh sakta hai.
- ✅ Wo aapko internet se disconnect kar sakta hai (DDoS Attack).
- ❌ Sirf IP se wo aapke phone ke files/photos access nahi kar sakta (Jab tak router me kami na ho).
Attackers usually kya try karte hain?
Open ports scan, weak router password, old firmware vulnerabilities, remote management ON hona, ya DDoS.
Protection Checklist (Must‑do)
Router ka admin password strong rakho, firmware update, Remote Management OFF, UPnP OFF (agar zaroori nahi), aur unknown devices ko Wi‑Fi se block karo.
💻 Tech Corner: IP Detective
Chaliye dekhte hain aapke device ki IP kya hai.
Task: Google par search karein "What is my IP". Wo jo dikhega, wo aapki Public IP hogi. Note karein ki wo CMD wali IP se alag hogi.
🛠️ Troubleshooting Corner (Internet Slow/Not Working?)
Agar Wi‑Fi connected hai par internet nahi chal raha, to ye simple checks try karein:
Agar 8.8.8.8 ping ho raha hai lekin google.com nahi, to mostly DNS
issue hota hai.
📝 Quiz Time
Q1: Router restart karne par IP badal gayi. Ye kaunsi IP thi?
Q2: Kaunsa address kabhi change nahi hota (Device ka Fingerprint)?
Q3: Ghar ke andar devices ko IP kaun deta hai?
Q4: 127.0.0.1 ka use kis liye hota hai?