The following terms are used throughout this chapter:
Internet Service Provider (ISP) . An ISP is a company that provides access to the Internet. Typically, the ISP lets your computer access the World Wide Web and provides e-mail services.
Internet Protocol (IP) address . An IP address is a set of four numbers, each ranging from zero to 255, separated by periods; for example, 192.168.0.67. Every computer connected to the Internet must have a unique IP address.
Host name and domain name. A host name and domain name together are a plain English version of your IP address. The host name is the name of your computer; the domain name identifies the company, ISP, or other organization your computer is "attached" to. For example, in the name fido.be.com, "fido" is the name of a computer within the domain "be.com".
Domain Name Server (DNS). A DNS is a computer that converts IP addresses into host/domain names. If there's a DNS machine on your network, you can access other machines by their host/domain names--for example, DNS lets you specify www.be.com in a NetPositive browser window. Without DNS, you would tell NetPositive to take you to 207.126.103.9.
Dynamic Host Configuration Protocol (DHCP). A DHCP server is computer that resolves addresses automatically. DHCP makes configuring your computer easier--you don't have to supply an IP address, for example--but not all computers have access to DHCP.
Point to Point Protocol (PPP). You connect to the Internet via PPP if you're using a modem (as opposed to an Ethernet connection). If you use PPP, you don't need to specify an IP address for your computer. Instead, you have to supply the phone number, user name, and password that you use to connect your modem to the net. You get this information from your ISP.
Gateway (aka "router"). A gateway is another computer, identified by IP address, through which your computer transmits data from your local network out to a larger network or the Internet
Subnet mask. This is an IP address that's used to determine your local network. In most cases, the subnet mask is 255.255.255.0.