DHCP Basics

Automatic IP address assignment in networks


+ What is DHCP?

DHCP (Dynamic Host Configuration Protocol) automatically assigns IP addresses and network settings to devices in a network.

+ Why do we need DHCP?
  • Eliminates manual IP configuration
  • Prevents IP address conflicts
  • Saves time and reduces errors
  • Centralized IP management
+ DHCP DORA Process
  1. Discover – Client broadcasts request
  2. Offer – Server offers IP
  3. Request – Client requests IP
  4. Acknowledge – Server confirms lease
+ DHCP Scope

A DHCP scope defines the range of IP addresses that can be assigned to clients along with subnet mask, gateway, and DNS.

+ DHCP Lease Time

Lease time determines how long a client can use an IP address before it must be renewed.

+ DHCP Reservation

DHCP reservation assigns a fixed IP to a device based on its MAC address (used for servers, printers, CCTV).

+ Real-World Example

In offices and hospitals, DHCP assigns IPs to laptops, desktops, Wi-Fi devices, and VoIP phones automatically.