Evolution of Data-Oriented Networks

Evolution of Data-Oriented Networks
Table 2.2 outlines the chronology of development of data-oriented networks. As discussed
in Chapter 1, data-oriented wireless networks can be divided into wide-area

TABLE 2.2 History of Data-Oriented Wireless Networks
Diffused infrared: 1979 (IBM Rueschlikon Labs, Switzerland)
Spread spectrum using SAW devices: 1980 (HP Labs, California)
Wireless modems: early 1980s (Data Radio)
ARDIS: 1983 (Motorola/IBM)
ISM bands for commercial spread-spectrum applications: 1985
Mobitex: 1986 (Swedish Telecom and Ericsson)
IEEE 802.11 for wireless LAN standards: 1990
Announcement of wireless LAN products: 1990
RAM mobile: 1991 (Mobitex)
Formation of WINForum: 1992
ETSI and HIPERLAN in Europe: 1992
Release of 2.4-, 5.2-, and 17.1- to 17.3-GHz bands in EC: 1993
PCS licensed and unlicensed bands for PCS: 1994
CDPD: 1993 (IBM and nine operating companies)
Wireless ATM Forum started: 1996
U-NII bands released, IEEE 802.11 completed, GPRS started: 1997
IEEE 802.11b and Bluetooth announcement: 1998
IEEE 802.11a/HIPERLAN2 started: 1999
TABLE 2.3 Properties of ISM Bands
Frequencies of operation:
902 to 928 MHz; 2.4 to 2.4835 GHz; 5.725 to 5.875 GHz
Transmitter power limitation of 1 W for DSSS and FHSS
Low power with any modulation
wireless data and local broadband and ad hoc networks. Wireless local networks support
higher data rates and ad hoc operation for lower numbers of users. Broadband
wireless local networks are usually referred to as WLANs, and ad hoc local networks
as WPANs. The concept of WLAN was introduced around 1980. However, the first
WLAN products did not emerge until about 10 years later. Today, a key feature of local
broadband and ad hoc networks is operation in unlicensed bands. The first unlicensed
bands were the industrial, scientific, and medical (ISM) bands made available in the
United States in 1985. Table 2.3 provides a summary of the ISM bands. Later, in
1994 and 1997, the PCS and U-NII unlicensed bands were also designated in the
United States.
The major WLAN standardization activity is IEEE 802.11, begun in the late 1980s
and completed in 1997. The IEEE 802.11 and 802.11b operate in the ISM bands, and
IEEE 802.11a operates in the U-NII bands. Another extension of 802.11, IEEE 802.11g,
ratified in mid-2003, provides data rates and performance comparable to 802.11a but
operates in the 2.4-GHz band. The competing European standard for WLAN is HIPERLAN,
developed by the Broadband Radio Access Networks (BRAN) division of ETSI.  The HIPERLAN1 standard was completed in 1997. Its successor, HIPERLAN2, is similar
to IEEE 802.11a but operates in the 5-GHz band. However, by the time that the
HIPERLAN2 standard was settled, adoption of the IEEE 802 standards was spreading
widely, and the 802.11b and 802.11a standards now dominate the WLAN marketplace.
In 1996 the wireless ATM Forum was formed to merge ATM technology with wideband
local access. More recently, following the announcement of Bluetooth technology
in 1988, WPANs have attracted tremendous attention. WPANs exhibit more restricted
coverage than do traditional WLANs, and they are intended to provide a better ad
hoc environment for interconnecting personal equipment such as laptop, cell phone,
and headset. Today, IEEE 802.11-based products generate most of the income for this
industry, currently about half a billion dollars per year. In the past several years, major
investments have been made in WLAN and WPAN chip-set developments all over the
world. These investments are being made with the expectation of sizable sales volumes
generated by integration of WLANs with cellular systems as well as a large WPAN
market for consumer products and home-networking systems.
Mobile data services were introduced in 1983 with the ARDIS project, a collaboration
between Motorola and IBM. The purpose of this network was to allow IBM field
crews to operate their portable computers on customer premises. In 1986, Ericsson
introduced Mobitex technology. which was an open-architecture implementation of
the ARDIS system. In 1993, IBM and nine operating companies in the United States
initiated the Cellular Digital Packet Data (CDPD) project, expecting a huge market
by the year 2000. In late 1990s, GPRS data services were integrated into the successful
GSM systems and can support an order-of-magnitude-higher data rates than
those of previous technologies, attracting considerable attention. These higher data
rates are perceived to be essential for wireless Internet access, thus far the most popular
wireless data application. The third-generation cellular systems are projected to
provide a mobile data service up to 2 Mb/s, substantially higher than the GPRS data
rates. The third-generation data rates would not, however, have the comprehensive
geographic coverage of GPRS. The early mobile data networks, ARDIS and Mobitex,
were independent networks owning their infrastructure. In contrast, CDPD service used
infrastructure overlaid onto AMPS systems, and GPRS was actually integrated into the
GSM infrastructure. Thus, we have seen the gradual assimilation of the mobile data
industry into the cellular telephone industry, and this will be completed in the next
generation of cellular systems.
With integration of the PCS and mobile data industries into the next generation of
cellular systems, we see the emergence of two industries: next-generation wide-area
cellular systems operating in licensed bands, and local broadband and ad hoc networks
operating in unlicensed bands.