What is DHCP?
The Internet is a source of information that is continuously updated and accessed via computers and other devices. For a device to connect to the Internet, it must have an Internet Protocol (IP) which is the computer¡¯s address on the Internet. As an example of IP address is an individual's telephone number, which is an identifier for people to communicate with the individual.
Up until the late 1980s, configuring a computer to connect to the Internet was a manual process. For network administrators to manage large numbers of computers on a network, a new and improved TCP/IP network protocol, Dynamic Host Configuration Protocol (DHCP) was introduced. DHCP is controlled by a DHCP server. Your router can be a DHCP server. When DHCP servers are unavailable and the TCP/IP is set to get IP addresses from DHCP, 169.254.xxx.xxx addresses will be assigned.
How DHCP Works?
As its name indicates, DHCP provides dynamic IP address assignment. What this means is that instead of having to rely on a specific IP address, a computer will be assigned one that is available from a subnet or "pool" that is assigned to the network. DHCP also extends BOOTP functionality to provide IP addresses that expire. BOOTP indirectly uses a form of leasing that never expired, but the term wasn't actually used until the introduction of DHCP. When DHCP assigns an IP address, it actually leases the identifier to the host computer for a specific amount of time. The default lease is five days, but a network administrator should evaluate their own particular circumstances to determine an appropriate lease.
