4.9.4.7 Dynamic Host Configuration Protocol (DHCP)

Question 1

How does DHCP work?

Answer 1

The router allocates IP addresses using DHCP protocol.
A device (the client) requests an IP address from a router (the host), after which the host assigns an available IP address to allow the client to communicate on the network.
A DHCP server defines a scope, or pool, of IP addresses that it uses to serve devices with an address.

Question 2

What is the purpose of DHCP?

Answer 2

Rather than have every machine in the network given a fixed IP address we allocate IP addresses to those machines as and when they connect

Question 3

What are the advantages / disadvantages of DHCP?

Answer 3

It is possible to have more machines than available IP addresses on the assumption that everyone wont be using the network at once. We don’t have to manually assign IP addresses and so saves time and avoids the possibility of accidentally assigning the same IP address twice.
Tracing internet activity may be difficult as the same machine may have two or more different IP addresses over a period of time. Any device being used as a server cannot be allocated an IP address dynamically.