IP address
This address is an unique numbers that identifies a computer or device on the WAN or LAN. These numbers are usually shown in groups separated by periods, for example: 123.123.23.2.

Subnet Mask
Subnets allow network traffic between hosts to be separated based on the network's configuration. In IP networking, traffic takes the form of packets. IP subnets advance network security and performance to some level by organizing hosts into logical groups. subnet masks contain four bytes and usually appear in the same "dotted decimal" data. For example, a very common subnet mask in its binary demonstration 11111111 11111111 11111111 00000000 will usually be shown in the corresponding, more readable form
255.255.255.0

Gateway
A gateway is a piece of software or hardware that passes information between networks. You'll see this term most often when you either log in to an Internet site or when you're transient email between different servers.

DHCP
DHCP is a protocol for dynamically assigning IP addresses to networked computers. With DHCP, a computer can automatically be given an exclusive IP address each time it logs on to a network--making IP address management an easier job for network administrators. When a computer connects to the network, the DHCP server selects an IP address from a master list and assigns it to the system. The device must set to "Obtain the IP address automatically". The Wireless Access Point Gateway's DHCP server is enabled by default. If you would like to disable the DHCP server, click on the "Off" bottom.

DNS
When you send email or position a browser to an Internet domain such as xxxxx.com, the domain name system translates the names into IP addresses. The term refers to two things: the conventions for naming hosts and the way the names are control across the Internet.