DHCP Engineer

DHCP stands for Dynamic Host Configuration Protocol. It is used to dynamically provide ip address, dns-address, default gateway etc information to each host in a LAN.

DHCP uses UDP transport protocol and port number 67 and 68 for server nad client respectively. Ipv4 uses stateful DHCP whereas IPv6 uses either stateful or stateless DHCP server. 

Client while booting up broadcasts DISCOVER message to the LAN, DHCP server on receiving the message sends out OFFER to requesting host. Now client selects the ip address according to its criteria, and if multiple DHCP servers send back replies client only selects one DHCP server. The client sends out the selected ip address in DHCP REQUEST message. The DHCP server then assigns the ip address to the host and sends out ACK.

Know more: what is the purpose of DHCP?

DHCP Server is a pool of IP Addresses which assign the IP address to the computers joined on a network. 

Example: You have a wireless Internet router at home which has DHCP enabled, when you connect your laptop/PC/Phone to the network all the devices get the unique IP Address same subnet and same Gateway, if you have to do it manually without DHCP server than you also have to remember what IP you have assigned to which device. 
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