Wimax standards and Security The Wimax

1.2.2 IEEE 802.20
The IEEE 802.20 standard defines a wireless broadband networking tech- nology operating in bands below 3.5 GHz with data rates around 1 Mbps.

IEEE 802.20 aims to operate in ranges up to 15 km, supporting vehicular motion up to 250 km/h (train speeds). Activities of this group were suspended on June 8, 2006, but a path forward was established on September 15, 2006 by the IEEE Standards Association to continue the development of the standard. Currently, a draft standard has been produced but this working group is still in its early stages and as such a final standard is expected to emerge no earlier than late 2007.

3. 
   Cellular Networks
   

Cellular technology has long evolved from first-generation analog technology to today’s Internet-enabled digital cellular packet networks. Originally such networks were designed to provide voice service, but today’s information- centric users demand other services as well, such as e-mail, text messaging, and wireless Internet browsing. Figure 1.4 illustrates the evolution of cellular technology from second generation to third generation. Here, the evolution of the two primary technologies deployed today is shown: code division mul- tiple access (CDMA) and Global System for Mobile communications (GSM). GSM is largely a time division multiple access (TDMA) system.
The third-generation partnership project (3GPP) was established in December 1998 as a collaboration between multiple regional telecommuni- cations standards bodies: the Association of Radio Industries and Business
Cellular Technology Evolution




1xRTT
(50 Kbps)

1xEVDO/1xEVDV

(1 Mbps)




GPRs
(20 Kbps)

CDMA (14.4 Kbps)

EDGE
(100 Kbps)

WCDMA/HSDPA

(1 Mbps)
3G

GSM/TDMA
(9.6 Kbps)
2.5G