User's Manual

Chapter 5 Wireless
B222s User’s Guide
58
5.7.1 Additional Wireless Terms
The following t able describes som e wireless network t erm s and acronym s used in the LTE Device’s
web configurat or.
5.7.2 Wireless Security Overview
By their nature, radio com m unicat ions are sim ple to int ercept . For w ireless data networks, this
m eans t hat anyone wit hin range of a wireless net work without security can not only read the dat a
passing over the airwaves, but also j oin the network. Once an unaut horized person has access t o
the network, he or she can st eal inform at ion or int roduce m alwar e ( m alicious soft ware) intended t o
com prom ise t he network. For t hese reasons, a variety of security system s have been developed t o
ensure that only authorized people can use a wireless dat a net work, or understand t he data carried
on it .
These security standards do t wo t hings. First , t hey aut hent icat e. This m eans t hat only people
present ing t he right credent ials ( oft en a usernam e and password, or a “ key” phrase) can access t he
network. Second, they encr ypt . This m eans t hat the inform at ion sent over t he air is encoded. Only
people wit h t he code key can understand t he inform at ion, and only people who have been
authent icat ed are given t he code key.
These security standards vary in effect iveness. Som e can be broken, such as t he old Wired
Equivalent Protocol ( WEP) . Using WEP is bet t er t han using no securit y at all, but it will not keep a
det erm ined at tacker out . Other security standards are secure in t hem selves but can be br oken if a
user does not use t hem properly. For exam ple, the WPA-PSK securit y standard is very secure if you
use a long key which is difficult for an at t acker ’s software to guess - for exam ple, a twenty- letter
long st ring of apparent ly random num bers and let t ers - but it is not very secure if you use a short
key which is very easy t o guess - for exam ple, a three- lett er w ord from t he dictionary.
Because of t he dam age t hat can be done by a m alicious at tacker, it ’s not j ust people who have
sensit ive inform ation on t heir network who should use securit y. Everybody who uses any wireless
network should ensure t hat effect ive securit y is in place.
Table 17 Addit ional Wireless Term s
TERM DESCRIPTION
RTS/ CTS Threshold I n a wireless network w hich covers a large area, wir eless devices are
som etim es not aware of each ot her’s presence. This m ay cause t hem t o
send infor m at ion to t he AP at t he sam e t im e and result in inform ation
colliding and not getting t hrough.
By set ting t his value lower t han t he default value, t he wir eless devices m ust
som et im es get perm ission t o send inform ation to t he LTE Device. The lower
the value, t he m ore oft en t he devices m ust get perm ission.
I f this value is greater t han the fragm entat ion t hreshold value ( see below),
then w ireless devices never have t o get perm ission t o send inform at ion to
the LTE Device.
Pream ble A pream ble affects t he t im ing in your wireless netw ork. There are t wo
pream ble m odes: long and short .
I f a device uses a different pream ble m ode
than t he LTE Device does, it cannot com m unicate w ith the LTE Device.
Aut hent icat ion The process of verifying whet her a wireless device is allowed t o use t he
wireless net work.
Fragm ent ation
Threshold
A sm all fragm ent ation t hreshold is recom m ended for busy network s, while a
larger t hreshold pr ovides fast er perform ance if the net work is not very busy.