Paper Info
Title
Enabling location-based services on wireless LANs
Abstract
The wide deployment of IEEE 802.11 Wireless Local Area Networks (WLANs) has made possible the development of application services on WLANs. Due to the small cell size in WLANs, it is practical to develop location dependent services based upon the awareness of the WLAN access points (AP) that mobile devices currently access. In this paper, we propose a location determination technique using the inherent SNMP support in WLAN APs. It is shown that the location of a mobile device can be determined effectively from the SNMP traps sent by APs. Our SNMP-based approach doesn't need any particular software or hardware in mobile devices. This paper also considers how to determine the location of a mobile device by its IP address. In general, only the IP address of a mobile device can be seen by location-based services. However, APs identify each mobile device by its MAC address. Hence, we propose effective techniques for the mappings between IP addresses and MAC addresses. Through the address mappings, the location of a mobile device can be determined by its current IP address. We further propose a web service framework to enable WLAN location-based services in WWW environments. To verify our approach, we also develop a location-based campus map service based on the web service framework. In indoor environments, the coverage area of a typical IEEE 802.11 AP is usually small, compared with the size of cells in cellular telecommunication systems. Therefore, if we can identify the AP that a mobile device accesses currently, we can determine that the mobile device is in the neighborhood of the AP. Hence, it is practical to provide location dependent information to the mobile device based on the location of the AP. In this paper, we will show that the inherent Simple Network Management Protocol (SNMP) (2) supported in each AP can be used to determine which AP a mobile device is currently connected to. As known, most WLAN APs support SNMP for network management purposes. In an IEEE 802.11 WLAN, when a mobile device attempts to access the network, the device will first make an association with its nearest AP. For effective management of association services, many APs are capable of sending association notifications to their network manager via SNMP traps. That is, whenever a mobile device successfully makes an association with an AP, the AP will immediately send an SNMP association trap to notify its management station. Similarly, the re-associations and disassociations between mobile devices and APs will also trigger the transmissions of re-association traps and disassociation traps, respectively. By receiving the SNMP traps sent from APs, we can know which mobile device is entering or leaving the coverage area of an AP. As a result, the approximate location of a mobile device can be determined as soon as its migration to the coverage area of an AP. In this paper, we will develop an effective location determination technique by means of the SNMP supported in APs. By o ur approach, no any particular hardware and software is required in mobile devices. In the wired network, only a location server is needed to receive SNMP traps from APs and to perform location determinations. Since SNMP traps are sent immediately after associations are made, we will show that location determination via SNMP traps can achieve shorter response time and higher accuracy than previous approaches. Many Internet application services are designed to be web- based. This paper also aims to enable WLAN location-based services in WWW environments. If a location-based service can be implemented as a web application, the web browser in a mobile device will be the only required software to access location dependent information Previous location determination approaches use particular hardware or software in mobile devices to perform location detection. These approaches were not appropriate for use in WWW environments. Since we assume that the web browser is the
Year
DOI
Venue
2003
10.1109/ICON.2003.1266251
ICON
Keywords
Field
DocType
mobile device,network management,information management,wireless local area network,simple network management protocol,world wide web,it management,hardware,local area networks,web services,location based service,web service
Wireless,MAC address,Computer science,Computer network,Location-based service,Mobile device,Network detector,Local area network,Web service,Simple Network Management Protocol,Distributed computing
Conference
ISSN
ISBN
Citations 
1531-2216
0-7803-7788-5
0
PageRank 
References 
Authors
0.34
7
3
Name
Order
Citations
PageRank
Yen-Cheng Chen115215.38
Yao-Jung Chan210.71
Cheung-Wo She310.71