Cisco WRV54G - Manual (Page 8)

4 Chapter 2: Planning your Wireless Network
The Router’s Functions
Wireless-G VPN Broadband Router
Chapter 2: Planning your Wireless Network
The Router’s Functions
Simply put, a router is a network device that connects two networks together.
In this instance, the Router connects your Local Area Network (LAN), or the group of PCs in your home or office, to
the Internet. The Router processes and regulates the data that travels between these two networks.
The Router’s NAT feature protects your network of PCs so users on the public, Internet side cannot “see” your
PCs. This is how your network remains private. The Router protects your network by inspecting every packet
coming in through the Internet port before delivery to the appropriate PC on your network. The Router inspects
Internet port services like the web server, ftp server, or other Internet applications, and, if allowed, it will forward
the packet to the appropriate PC on the LAN side.
Remember that the Router’s ports connect to two sides. The LAN ports connect to the LAN, and the Internet port
connects to the Internet. The LAN and Internet ports transmit data at 10/100Mbps.
IP Addresses
What’s an IP Address?
IP stands for Internet Protocol. Every device on an IP-based network, including PCs, print servers, and routers,
requires an IP address to identify its “location,” or address, on the network. This applies to both the Internet and
LAN connections. There are two ways of assigning an IP address to your network devices. You can assign static
IP addresses or use the Router to assign IP addresses dynamically.
Static IP Addresses
A static IP address is a fixed IP address that you assign manually to a PC or other device on the network. Since a
static IP address remains valid until you disable it, static IP addressing ensures that the device assigned it will
always have that same IP address until you change it. Static IP addresses must be unique and are commonly
used with network devices such as server PCs or print servers.
LAN: the computers and networking products that
make up your local network
NOTE: Since the Router is a device that connects two
networks, it needs two IP addresses—one for the LAN,
and one for the Internet. In this User Guide, you’ll see
references to the “Internet IP address” and the “LAN IP
address.”
Since the Router uses NAT technology, the only IP
address that can be seen from the Internet for your
network is the Router’s Internet IP address. However,
even this Internet IP address can be blocked, so that the
Router and network seem invisible to the Internet—see
the Block WAN Requests description under Filters in
“Chapter 7: The Router’s Web-based Utility.”
Figure 2-1: Network