From IP Location


Wireless technologies have advanced significantly in recent years, particularly those based on the IEEE 802.11 series of standards. Wireless technologies are a very attractive networking option in light of dramatic improvements in speed, usability, security, and mobility. The convenience of being able to deploy a network without the need to install cables is also a great advantage of wireless networking.

Location technologies in this area share some similarities with those used in cellular networks, the same basic primitives of location location measurements can be used for WiFi. However, WiFi presents a new set of challenges. In particular, ad hoc network architectures present difficult problems for location determination.

In this chapter, location determination in WiFi networks is examined. Basic technology options and how they can be applied in both infrastructure and ad hoc variants are discussed. These options are described with the LIS and ALE architecture in mind.

802.11 Wireless LANs

The 802.11 series of standards have made wireless network connectivity accessible for a great many people. Wireless LANs provide an alternative to wired Ethernet, and offer many advantages, particularly in terms of ease of use and ubiquity. Wireless LANs can be found in many workplaces and public areas for instance, a great many airports make a WLAN available to people awaiting flights.

Wireless LANs fall into two categories: infrastructure-based and ad hoc. Infrastructure WLANs rely on access points (APs) to provide a connection to a wired LAN, as well as a central point for communication. Public wireless hotspots, such as those at...

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Products & Services
WiFi and WiMAX Wireless Chips
WiFi wireless chips and WiMAX wireless chips are used in fixed broadband wireless access networks that use point-to-multipoint architecture.
Communication Site Maintenance Services
Communication site maintenance services maintain remote communication sites and client-owned (CO) infrastructure and equipment.
Wireless Systems
Wireless systems consist of combined RF components such as transmitters, receivers, transceivers, filters, down / up converters, antennas and antenna positioners.
Wireless Network Components
Wireless network components are used to build or replace worn out devices within a wireless network.
Auto Dialers
Auto dialers are alarms that send signals when equipment malfunctions, a process variable exceeds a predefined limit, or another alarm-triggering event occurs.

Topics of Interest

Overview So far we have looked at how we can determine and provide location in enterprise and residential wireline environments. We have explored location determination techniques that can be...

An ad hoc wireless network is a collection of wireless mobile nodes that self-configure to form a network without the aid of any established infrastructure, as shown in Figure 16.1. Without an...

Developing WLANs through the 802.11 Architecture The 802.11 architecture can best be described as a series of interconnected cells, and consists of the following: the wireless device or station, the...

Farid Dowla Asis Nasipuri Overview A mobile ad hoc network, such as the one shown in Figure 12.1, is a collection of digital data terminals equipped with wireless transceivers that can communicate...

Infrastructure-based wireless networks have base stations, also called access points, deployed throughout a given area. These base stations provide access for mobile terminals to a back-bone wired...