User's Manual

Chapter 7: Glossary
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Aut hentication a n d W EP Encr yption
The absence of a physical connection between nodes m akes t he wireless links vulnerable to
eavesdropping and inform ation theft . To provide a certain level of security , t he I EEE 802.11
st andard has defined t wo t ypes of authent ication m ethods, open system and shared key. Wit h
open system authent ication a wireless PC can j oin any network and receive any m essages t hat
are not encrypt ed. Wit h shared key authent icat ion, only those PCs that possess t he correct
authent ication key can j oin the network. By default I EEE 802.11 wireless devices operate in an
Open system network.
DHCP ( Dyn a m ic H ost Configura t ion Prot ocol)
When operates as a DHCP server, t he Wireless Broadband Rout er assign I P addresses t o t he
client PCs on t he LAN. The client PCs “ leases” t hese Private I P addresses for a user-defined
am ount of t im e. Aft er t he lease tim e expires, t he private I P address is m ade available for
assigning t o ot her net work devices.
The DHCP I P address can be a single, fixed public I P address, an your service provider assigned
public I P address, or a private I P address.
I f you enable DHCP server on a privat e I P address, a public I P address will have t o be assigned
to the NAT I P address, and NAT has t o be enabled so t hat t he DHCP I P address can be
translated int o a public I P address. By this, t he client PCs are able t o access t he I nt ernet .
I nfrastructure m ode
A backbone t o ext end t he service provided by net work. This m ode provides wireless
connect ivit y t o m ult iple wireless net work devices within a fixed range or area of coverage,
int eracting w it h wireless nodes via an ant enna.
LAN ( Local Ar e a N e t w ork) & W AN ( W ide Ar e a N e t w ork)
A LAN is a com put er net work lim it ed t o t he im m ediate area, usually t he sam e building or floor
of a building. A WAN, on t he ot her hand, is an out side connect ion t o another network or the
I nt ernet .
The Ethernet side of t he Wireless Broadband Rout er is called t he LAN port. I t is a t wist ed- pair
Et hernet 10Base- T int erface. A hub can be connected t o the LAN port . More t han one
com put ers, such as server or print er, can be connect ed t hrough this hub to t he Wireless
Broadband Router and com poses a LAN.
The WAN port of t he Wireless Broadband Rout er com poses t he WAN int erface, which support s
PPP or RFC 1483 connect ing t o another rem ot e DSL device or cable m odem .
MAC Address
Media Access Code Address. A unique, 48- bit num ber assigned t o every network interface card
by t he m anufacturer.
N AT ( N e t w ork Address Tr a nsla t ion) I P Address
NAT is an I nternet standard that translates a privat e I P wit hin one net work t o a public I P
address, eit her a static or dynam ic one. NAT provides a t ype of firewall by hiding int ernal I P
addresses. I t also enables a com pany to use m ore internal I P addresses.
I f t he I P addresses given by your your service provider are not enough for each PC on t he LAN
and t he Wireless Broadband Rout er, you need t o u se NAT. Wit h NAT, y ou m ak e u p a p r iv at e I P
network for t he LAN and assign an I P address from t h a t n e t w o r k t o e a c h PC. On e o f s o m e p u b l ic
addresses is configured and m apped t o a privat e workstation address when accesses are m ade
through the gateway t o a public net work.
For exam ple, the Wireless Broadband Router is assigned with t he public I P address of
168.111.1.1. With NAT enabled, it creates a Virt ual LAN. Each PC on t he Virtual LAN is assigned