IP Addresses Explained: Why We Ran Out (and Why You're Still Online)

What is an IP address, and how do billions of devices get online when IPv4 only has about 4.3 billion addresses? This video walks through IPv4 bit by bit, network vs host (/24), how switches and routers move your data, private vs public IP addresses, NAT, 127.0.0.1 and 169.254, and IPv6. Visual, beginner friendly, and accurate enough for engineers: cloud, DevOps, SRE and networking, one story at a time. A solid foundation if you're starting CCNA or Network+. Chapters 00:00 The impossible math 00:32 What is an IP address? 00:58 IPv4 explained: 8 bits, 32 bits, 4.3 billion 01:48 Network vs host part (/24 explained) 02:38 Switches, routers and routing 04:14 Why we ran out of IPv4 04:41 Private vs public IP addresses 06:33 NAT: how your whole home shares one IP 07:09 What is 127.0.0.1 and 169.254? 07:40 IPv6 explained, and how to find your IP 08:41 Recap In this video IPv4: why each number goes from 0 to 255, and why 32 bits means 4.3 billion Network part vs host part, and what /24 means Switches vs routers: MAC address, default gateway, routing table, traceroute Private vs public IP addresses, and how to spot the private ranges (10, 172.16-31, 192.168) NAT: how your whole home shares one public IP 127.0.0.1 (localhost) and 169.254 (a DHCP troubleshooting clue) IPv6: hexadecimal, leading zeros and the double colon How to find your own IP: ipconfig, ip addr, ifconfig, and what is my IP Next up: subnetting, step by step. More from Tech Story: https://techstoryexplained.com Sources and notes IPv4: RFC 791 (1981). Private ranges: RFC 1918. Link-local: RFC 3927 IANA allocated its last free IPv4 blocks in 2011; RIPE NCC (Europe) ran out in 2019 All example addresses are from documentation ranges #networking #ipaddress #ccna