DHCP
Dynamic Host Configuration Protocol
ELI5 — The Vibe Check
DHCP is the system that automatically assigns IP addresses to devices when they join a network. When your phone connects to WiFi, it sends out a request like 'I need an IP address!' and the DHCP server says 'here, use 192.168.1.42' — automatically, no setup needed.
Real Talk
DHCP is a network protocol that automatically assigns IP addresses and other network configuration (subnet mask, gateway, DNS servers) to devices on a network. The process is DORA: Discover, Offer, Request, Acknowledge. Assignments are called leases and expire after a set time.
Show Me The Code
# Check DHCP lease info on Linux
cat /var/lib/dhcp/dhclient.leases
# Or with ip command
ip addr show eth0
# DHCP lease info shows:
# IP address assigned
# Lease duration
# DNS servers
# Default gateway
When You'll Hear This
"The server needs a static IP — take it out of the DHCP pool." / "DHCP leases expire every 24 hours on this network."
Related Terms
DNS (Domain Name System)
DNS is the internet's phonebook. You type 'google.
IP Address
An IP address is your device's home address on the internet.
NAT (Network Address Translation)
NAT is how your home router lets all your devices share one public IP address. Your phone, laptop, and TV each get a private IP (192.168.x.
Subnet
A subnet is a smaller chunk of a larger network, like dividing a city into neighborhoods. All devices in a subnet can talk to each other directly.