IP Address Basics
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Everything you need to know about IP addresses — from fundamentals to advanced concepts. What they are, how they work, and why they matter.
What Is an IP Address?
Learn what IP addresses are, how they work, and why every device on the internet needs one.
5 分钟阅读Public vs Private IP Addresses
Understand the difference between public and private IPs, RFC 1918 ranges, and how NAT connects them.
5 分钟阅读How to Find Your IP Address
Step-by-step instructions to find your public and private IP on Windows, Mac, Linux, and mobile.
4 分钟阅读IP Geolocation: How Accurate Is It Really?
Explore how IP geolocation works, its accuracy limitations, and why your IP might place you in the wrong city.
10 分钟阅读IP Reputation and Blacklists Explained
Understand how IP reputation scoring works, why addresses get blacklisted, and how to check and restore your IP's standing.
11 分钟阅读Carrier-Grade NAT (CGNAT): What It Means for You
Learn how ISPs use CGNAT to share public IPs among hundreds of customers and what it means for gaming, hosting, and privacy.
10 分钟阅读Network Address Translation (NAT) Explained
Learn how NAT translates private IP addresses to public ones, enabling millions of devices to share a single public IP.
8 分钟阅读IP Address Classes (A, B, C, D, E)
Understand the original classful IP addressing system with Class A through E, their ranges, and why CIDR replaced it.
7 分钟阅读Loopback & Localhost: 127.0.0.1 Explained
Understand the loopback interface, why 127.0.0.1 is special, and how localhost is used for local development and testing.
6 分钟阅读How IP Addresses Are Assigned (IANA, RIRs, ISPs)
Trace the chain of IP address allocation from IANA to Regional Internet Registries to ISPs and finally to your device.
8 分钟阅读IP Spoofing: Risks and Prevention
Learn how attackers forge source IP addresses, the threats IP spoofing enables, and the defenses that protect against it.
7 分钟阅读What's My IP: How IP Detection Works
Discover how websites detect your IP address, the role of HTTP headers, proxies, VPNs, and what your IP reveals about you.
6 分钟阅读Multicast, Anycast, and Broadcast Explained
Learn the three methods of one-to-many communication in IP networks: multicast, anycast, and broadcast.
8 分钟阅读IPv4 Address Exhaustion: Causes and Solutions
Understand why the 4.3 billion IPv4 addresses ran out, the timeline of exhaustion, and the technologies extending IPv4's life.
8 分钟阅读IP Address Conflicts: Causes and Fixes
Learn what causes IP address conflicts on your network, how to diagnose them, and proven methods to resolve and prevent duplicate IP issues.
6 分钟阅读IPv4 Header Structure Explained
Break down the IPv4 packet header field by field, understanding version, TTL, protocol, checksum, and addressing fields.
9 分钟阅读IANA and IP Address Governance
Understand how IANA, ICANN, and the multistakeholder model govern IP address allocation and internet numbering resources.
7 分钟阅读Regional Internet Registries (ARIN, RIPE, APNIC)
Explore the five RIRs that manage IP address distribution globally, their service regions, policies, and WHOIS databases.
8 分钟阅读IP Address Privacy: What Your IP Reveals
Learn what personal information your IP address exposes, how it is used for tracking, and practical steps to protect your privacy.
7 分钟阅读IP Address Lookup: Best Tools and Databases
Discover the best tools and databases for looking up IP addresses, including WHOIS, geolocation services, and threat intelligence platforms.
7 分钟阅读IP Geolocation: How Accurate Is It Really?
How IP geolocation databases work, why they are often wrong, and what factors determine accuracy at country, region, and city levels.
11 分钟阅读Carrier-Grade NAT (CGNAT) Explained
What CGNAT is, how ISPs share IPv4 addresses across thousands of subscribers, and how it affects hosting, gaming, P2P, and remote access.
12 分钟阅读