All network devices on a network/Internet need an IP address to operate.
There are two ways that the device can acquire an address. They are
- Manual Address assignment
- Automatic assignment.
Almost all networks use automatic assignment as it is easier and more reliable.
In order to have automatic assignment on your home network you need to have a dhcp server on the network. DHCP stands for dynamic Host configuration protocol.
All network devices come equipped with a dhcp client, and when they connect to a network they contact the dhcp server and request an IP address.
Provided everything is working Ok they get an IP address and now they can operate on the network.
On large networks an administrator must set up and manage the DHCP server but on home networks it is built into the router and doesn’t normally need any manual intervention.
Although on home networks you don’t have to configure the DHCP server you do need to tell the clients (computers) to use DHCP for IP addresses.
The video below shows how Windows XP is configured to use DHCP. If you are using windows 7 then the settings are similar.
Missing DHCP Server
If the client cannot find a DHCP server then It may auto assign an IP address from a reserved range 169.254.0.0-169.254.255.255 or simply have an IP address of 0.0.0.0.
In either case it is unlikely to work correctly.
You can find out whether or not your client (windows) has an IP by using the ipconfig command at a command prompt. See Finding IP Address
