Ip Addresses; Network Addressing; About Dhcp; About Pppoe - Watchguard Firebox X15 User Manual

IP Addresses

To send mail to a person, you must first know their physical address.
For a computer to send data to a different computer, it must first
know the address of that computer. A computer address is known as
an IP address. Only one device can use an IP address at a time.
An IP address is a group of four numbers divided by decimal points.
Some examples of IP addresses are:
• 192.168.0.11
• 10.1.20.18
• 208.15.15.15

Network addressing

ISPs (Internet service providers) assign an IP address to each device
on their network. The IP address can be static or dynamic. Each ISP
has a small number of IP addresses.
Static IP addresses are permanently assigned to a device. These
addresses do not change automatically, and are frequently used for
servers.
Dynamic IP addresses change with time. If a dynamic address is not
in use, it can be automatically assigned to a different device.
Your ISP can tell you how their system assigns IP addresses.

About DHCP

Many ISPs assign dynamic IP addresses through DHCP (Dynamic
Host Configuration Protocol). When a computer connects to the
network, a DHCP server at the ISP assigns that computer an IP
address. It is not necessary to assign IP addresses manually when
you use DHCP.

About PPPoE

Some ISPs assign their IP addresses through Point-to-Point Protocol
over Ethernet (PPPoE). PPPoE expands a standard dial-up connec-
tion to add some of the features of Ethernet and PPP. This system
allows the ISP to use the billing, authentication, and security sys-
tems of their dial-up infrastructure with DSL modem and cable
modem products.
User Guide
IP Addresses
5