ZyXEL Communications 2WG - Manual (Page 261)

ZyWALL 2WG Support Notes
All contents copyright (c) 2006 ZyXEL Communications Corporation.
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b. Installation Speed and Simplicity:
Installing a wireless LAN system can be fast and easy and can eliminate the need to pull cable through
walls and ceilings.
c. Installation Flexibility:
Wireless technology allows the network to go where wire cannot go.
d. Reduced Cost-of-Ownership:
While the initial investment required for wireless LAN hardware can be higher than the cost of wired
LAN hardware, overall installation expenses and life-cycle costs can be significantly lower. Long-term
cost benefits are greatest in dynamic environments requiring frequent moves and changes.
e. Scalability:
Wireless LAN systems can be configured in a variety of topologies to meet the needs of specific
applications and installations. Configurations are easily changed and range from peer-to-peer networks
suitable for a small number of users to full infrastructure networks of thousands of users that enable
roaming over a broad area.
H05. What is IEEE 802.11
The IEEE 802.11 is a wireless LAN industry standard, and the objective of IEEE 802.11 is to make
sure that different manufactures' wireless LAN devices can communicate to each other.802.11 provides
1 or 2 Mbps transmission in the 2.4 GHz ISM band using either FHSS or DSSS.
H06. What is 802.11b?
802.11b is the first revision of 802.11 standard allowing data rates up to 11Mbps in the 2.4GHz ISM
band. Also known as 802.11 High-Rate and Wi-Fi. 802.11b only uses DSSS, the maximum speed of
11Mbps has fallbacks to 5.5, 2 and 1Mbps.
The IEEE 802.11b standard has a nominal speed of 11 megabits per second (Mbps). However,
depending on signal quality and how many other people are using the wireless Ethernet through a
particular Access Point, usable speed will be much less.
H07. What is 802.11g?
802.11g is an extension to 802.11b. 802.11g increases 802.11b's data rates to 54 Mbps and still utilize
the the 2.4 GHz ISM. Modulation is based upon OFDM (orthogonal frequency division multiplexing)
technology. An 802.11b radio card will interface directly with an 802.11g access point (and vice versa)