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Chapter 2: Networking and Security Basics
An Introduction to LANs
Wireless-N Gigabit Security Router with VPN
Chapter 2: Networking and Security Basics
An Introduction to LANs
A Router is a network device that connects multiple networks together and forward traffic based on IP destination
of each packet.
The Wireless-N Gigabit Security Router can connect your local area network (LAN) or a group of PCs
interconnected in your home or office to the Internet. You can use one public IP address from the ISP through
WAN port and use the router’s Network Address Translation (NAT) technology to share this single IP address
among all the users.
The Router’s Network Address Port Translation (NAPT or NAT) technology protects your network of PCs so users
on the Internet cannot “see” your PCs. This is how your LAN remains private. The Router protects your network by
inspecting the first packet coming in through the Internet port before delivery to the final destination on one of
the Ethernet ports. 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.
Multiple Wireless-N Gigabit Security Routers can also be used to connect multiple LANs together. This usually
applies to a medium-sized or larger company where you want to divide your network into multiple IP subnets to
increase the intranet throughput and reduce the size of the IP broadcast domain and its interference. In this case,
you need one WRVS4400N for each subnetwork and you can connect all the WAN ports to a second level Router
or switch to the Internet. Note that the second level Router only forwards data packets through a wired network
so you don’t have to use the Wireless-N Gigabit Security Router. You can use any wired router in the Linksys
family, e.g. RVS4000, which has 4 LAN ports and 1 WAN port.
The following diagram shows an example that consists of two levels of routers and multiple LANs inter-connected
together. The wireless network is only available at the first level of router to provide end user connections. The
second level router can connect to dedicated Server PCs or routers that aggregates traffic from different LANs.
NAT (Network Address Translation):
NAT technology translates IP
addresses of a local area network to a
different IP address for the Internet.
LAN: the computers and networking products that
make up your local network
