Technical Guide · Reviewed 1 November 2026 · Primary Sources: IETF RFC 791, RFC 8200, IANA
What Is an IP Address?
An Internet Protocol (IP) address is a numerical network identifier assigned to every device interface connected to a TCP/IP network so routers can forward data packets between a sender and a destination.
Packet Journey: How an IP Address Carries Traffic from Your Device to a Website
192.168.1.14 (Private IPv4)
Your Wi-Fi router assigns your device a local private address via DHCP from RFC 1918 space. This address only works inside your home or office LAN.
192.168.1.1 → WAN Interface
Network Address Translation (NAT) rewrites the source address of outbound packets from your device’s private IP to your router’s upstream WAN address.
49.44.0.1 or 2405:200:1601::1
Your broadband or 4G/5G operator routes your traffic onto the public internet using a globally routable IPv4 or 128-bit IPv6 address allocated by APNIC.
203.119.101.1 (Destination IP)
The destination server reads your public IP address in the packet header so it knows where to send the response bytes back across the internet.
1. Why Every Internet Packet Needs Two IP Addresses
The internet does not maintain a dedicated circuit wire between your smartphone and a website server. Instead, data is split into small chunks called IP packets. Every IP packet header contains two mandatory numerical fields:
- Source IP Address: The network address of the sender (so the destination knows where to send reply packets).
- Destination IP Address: The network address of the receiving server (often resolved from a domain name using DNS).
Each router along the path inspects the destination IP address, compares its leading network bits against its routing table using longest-prefix matching, and forwards the packet to the next hop until it reaches the destination network.
2. The Two Active IP Versions: IPv4 and IPv6
Two versions of the Internet Protocol operate side by side on today's internet (compare IPv4 vs IPv6 in detail):
IPv4 (RFC 791)
Example: 49.44.0.1
Uses a 32-bit number written as four decimal octets (0–255). Provides 4.29 billion total addresses globally. Check yours with our IPv4 Checker.
IPv6 (RFC 8200)
Example: 2405:200:1601::1
Uses a 128-bit number written as eight hexadecimal groups. Widely deployed on Indian 4G/5G and fiber broadband networks. Test yours with the IPv6 Checker.
3. Dynamic vs. Static IP Addresses in India
Residential broadband and mobile connections in India almost always use dynamic IP addressing: your ISP assigns an available IP address (or a shared CGNAT session) automatically when your router or phone connects, and that address can change when your router reboots or your lease expires. Businesses hosting on-premise VPN gateways, mail servers, or CCTV relays typically purchase a static public IP from their ISP so the address remains fixed.
Want to see the public IP address your connection is using right now? Visit our What Is My IP homepage or inspect any address with the IP Address Lookup tool.
Technical Specifications & Protocol Facts
Authoritative parameters, dimensions, and IETF RFC compliance
| Parameter / Dimension | Technical Specification | Standard / Authority |
|---|---|---|
| Canonical Document Scope | What Is an IP Address? — Route /what-is-an-ip-address | IPAddressLookup.in Technical Reference |
| Supported Address Families | IPv4 (32-bit dotted-decimal) & IPv6 (128-bit hexadecimal) | RFC 791 / RFC 8200 / RFC 5952 |
| Authoritative Registration Protocol | Registration Data Access Protocol (RDAP) via IANA Bootstrap | RFC 7480–7484 / RFC 9224 |
| Special-Purpose Range Classification | Private LAN (RFC 1918), Shared CGNAT 100.64.0.0/10 (RFC 6598), ULA (RFC 4193) | RFC 6890 IANA Registry |
Frequently Asked Questions
Concise answers verified against IANA, APNIC, and IETF protocol standards
What is the primary purpose of What Is an IP Address??
Understand how packets travel from your device and home router through your ISP to internet destinations. Every output on IPAddressLookup.in follows IETF RFC standards and cites primary RIR/IANA sources.
Are IP and network queries on this page logged or shared with advertisers?
No. IPAddressLookup.in operates on a strict data-minimization model with stateless query execution, short-lived caching (15 minutes max for upstream RDAP/DNS), and zero persistent user lookup history.
How often is the technical documentation on IPAddressLookup.in reviewed?
All protocol calculators, RFC citations, and Indian telecom notes are verified by the 2026-11-01 editorial and engineering review cycle.
Related Network Tools & Technical Guides
Contextual utilities and reference documentation verified for this workflow
Diagnostic & Calculation Utilities
- IP Address Lookup
Inspect country/region, ASN, provider, special-range scope, and data provenance for any IPv4 or IPv6 address.
- IPv4 Checker
Inspect the visitor IPv4 address observed by the server, octet breakdown, and RFC 1918 / RFC 6598 CGNAT status.
- IPv6 Checker
Inspect 128-bit IPv6 reachability, eight-hextet structure, compressed/expanded form, and Indian dual-stack context.
What Is an IP? · Canonical: https://ipaddresslookup.in/what-is-an-ip-address · Reviewed: 2026-11-01
Reviewer: IPAddressLookup.in Technical Network Utility Group · Stateless Privacy · Accuracy & Data Limits