Apple MB321LL User Guide - Page 65

Important Networking Terms TCP/IP (Transport Control Protocol/Internet Protocol) TCP/IP is a collection of protocols that underlies almost every form of communication on the Internet. DHCP (Dynamic Host Configuration Protocol) DHCP is a method of automatically assigning IP addresses. Instead of permanently assigning addresses to individual users, addresses are assigned by the DHCP server when clients need them. This means that instead of entering several fields of long addresses, users need only to select DHCP as their configuration method for IP networking. PPP (Point-to-Point Protocol) PPP is the most common protocol for providing IP services over a dial-up modem. PPPoE (Point-to-Point Protocol over Ethernet) PPPoE is a protocol used on some DSL lines for providing IP services. It allows DSL network providers to bill customers using their existing PPP equipment. If your ISP provided you with PPPoE connection software, such as EnterNet or MacPoET, then you connect via PPPoE. With AirPort, you do not need to use a third-party PPPoE application. NAT (Network Address Translation) NAT is used to share one IP address among several computers. A device set up as a NAT router uses a collection of "private" IP addresses (in the range 10.0.1.2 to 10.0.1.200) to allow several computers to access the Internet using one "public" IP address. When a computer using a private IP address requests information from the Internet, the NAT router keeps a record of the computer making the request, and sends the information to the Internet using its own IP address. When the response comes back from the Internet, the NAT router forwards the packet to the appropriate computer. IP subnet An IP subnet is a local network as defined by IP network numbers. Connecting to a subnet involves connecting to the appropriate hardware network and configuring IP for that network. Chapter 5 Behind the Scenes 65