Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots最新文献

An analytical model of rate-adaptive wireless LAN and its simulative verification 速率自适应无线局域网的分析模型及其仿真验证

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080742

Carsten Burmeister, U. Killat, Jens Bachmann

引用次数: 5

Measurements of SIP signaling over 802.11b links 在802.11b链路上的SIP信令测量

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080743

Cristian Hesselman, H. Eertink, I. Widya, Erik Huizer

{"title":"Measurements of SIP signaling over 802.11b links","authors":"Cristian Hesselman, H. Eertink, I. Widya, Erik Huizer","doi":"10.1145/1080730.1080743","DOIUrl":"https://doi.org/10.1145/1080730.1080743","url":null,"abstract":"The Session Initiation Protocol (SIP) is a popular application-level signaling protocol that is used for a wide variety of applications such as session control and mobility handling. In some of these applications, the exchange of SIP messages is time-critical, for instance when SIP is used to handle mobility for voice over IP sessions. SIP may however introduce significant delays when it runs on top of UDP over lossy (wireless) links. These delays are the result of the exponential back-off retransmission scheme that SIP uses to recover from packet loss, which has a default back-off time of half a second.In this paper, we empirically investigate the delay introduced by SIP when it runs on top of UDP over IEEE 802.11b links. We focus on the operation of SIP at the edge of an 802.11b cell (e.g., to update a mobile host's IP address after a handoff) as this is where SIP's retransmissions scheme is most likely to come into play. We experiment with a few 802.11 parameters that influence packet loss on the wireless link, specifically with different link-level retransmission thresholds, signal-to-noise-ratios (SNRs), and amounts of background traffic. We conduct these experiments in a controlled environment that is free from interfering 802.11 sources.Our results indicate that (1) SIP usually introduces little delay except for an SNR range of a few dBs at the very edge of an 802.11 cell in which the delay increases sharply, and (2) that a maximum of four 802.11 retransmissions suffices to limit the delay introduced by SIP retransmissions. The first result is of interest to developers of SIP applications who have to decide at which SNR to initiate a handoff to another network. The second result allows network providers to optimize their 802.11b networks for delay sensitive SIP applications.","PeriodicalId":423859,"journal":{"name":"Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126749558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

- The random waypoint city model -: user distribution in a street-based mobility model for wireless network simulations 随机路点城市模型:用户分布在基于街道的移动模型中，用于无线网络模拟

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080749

Jan Kraaier, U. Killat

引用次数: 56

Developing spatially-aware content management systems for dynamic, location-specific information in mobile environments 为移动环境中的动态、特定位置信息开发空间感知内容管理系统

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080733

Harsha Tummala, Joel Jones

{"title":"Developing spatially-aware content management systems for dynamic, location-specific information in mobile environments","authors":"Harsha Tummala, Joel Jones","doi":"10.1145/1080730.1080733","DOIUrl":"https://doi.org/10.1145/1080730.1080733","url":null,"abstract":"Current location-aware information systems lack an effective method of maintaining and updating dynamic, location-specific content. We have developed a design for representing location-specific content that balances flexibility and comprehensibility. We have developed a web-based content management system that implements this design. The system provides an easy-to-use interface to tie any form of media-such as text, pictures, audio, or video-to a location.This work is directly applicable to various forms of location-aware systems, such as tourist information, campus guides, and vehicular on-board navigation. Our work enhances these systems by providing a greater range of content and a more dynamic information base than is currently available in extant systems. We describe how our design allows end-users to easily contribute spatial data to these systems, while simultaneously providing structure to their contributions. Mobile users, utilizing WLAN hotspots in common, real-world environments, can greatly benefit from and easily contribute to location-aware information systems driven by spatially-aware content management systems.","PeriodicalId":423859,"journal":{"name":"Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134577669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 24

A multimedia guidebook implementation using a bluetooth wireless information point network 一种使用蓝牙无线信息点网络的多媒体指南实现

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080736

Matthew J. A. D'Souza, A. Postula, N. Bergmann, M. Ros

{"title":"A multimedia guidebook implementation using a bluetooth wireless information point network","authors":"Matthew J. A. D'Souza, A. Postula, N. Bergmann, M. Ros","doi":"10.1145/1080730.1080736","DOIUrl":"https://doi.org/10.1145/1080730.1080736","url":null,"abstract":"This paper describes the implementation of a Bluetooth Village Guide Book (VGB) scenario for use in the Kelvin Grove Urban Village located in Brisbane, Australia. An Information Point Station Network (IPSN) was developed, along with software for two types of mobile computing devices. The implementation consists of several Information Point Stations (IPSs) placed at locations of significance, with access to information items on a centralized server. Once a user is registered on the network, he/she is given the opportunity to experience context and eventually user aware information on demand and in various multimedia formats. These information items are selected by the user, either by way of a menu system appearing on their mobile computing device or a more intuitive pointer-tag system. Information items are then 'beamed' to the user's mobile computing device for the user to view. The implementation was found to be successful and was tested with multiple users accessing information items from a given IPS as well as multiple IPSs attached to the centralized server. A multimedia guidebook communications protocol was also developed to overcome the varying Bluetooth capabilities of a range of mobile computing devices. The future work includes further developing the VBG software to include a user-registration system and other features.","PeriodicalId":423859,"journal":{"name":"Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129794792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

A novel unbalanced multiple description scheme for video transmission over WLAN 一种新的无线局域网视频传输的不平衡多重描述方案

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080737

A. Vilei, G. Convertino, Silvio Lucio Oliva, Roberto Cuppone

{"title":"A novel unbalanced multiple description scheme for video transmission over WLAN","authors":"A. Vilei, G. Convertino, Silvio Lucio Oliva, Roberto Cuppone","doi":"10.1145/1080730.1080737","DOIUrl":"https://doi.org/10.1145/1080730.1080737","url":null,"abstract":"Video communication over lossy packet networks such as the Internet or wireless links, is hampered by packet loss. Indeed, video quality severely degrades in presence of lost packets. This paper describes a technique based on Unbalanced Multiple Description Coding (UMD) to improve the robustness of video transmission. The proposed system relies on two descriptions, HR (High-Resolution) and LR (Low-Resolution) where LR description is primarily used as redundancy. HR and LR are produced by using different encoding parameters. The novelty of our approach, compared to other techniques based on UMD, is the use of different intra refresh periods for the produced descriptions. In particular we use shorter intra refresh period for LR description (in order to improve its resilience to bursts of packet losses), and higher intra refresh period for HR description (in order to improve coding efficiency). Moreover, a novel packetization scheme has been introduced in order to optimize network performance. This technique is able to produce acceptable quality even if redundancy percentage is less than packet loss rate. Therefore our UMD approach is suitable for multicast video distribution over WLAN (e.g. in \"hotspots\") where estimating packet loss can be a difficult task because different receivers experience different loss patterns.","PeriodicalId":423859,"journal":{"name":"Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126036610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

An approach to enhance inter-provider roaming through secret sharing and its application to WLANs 一种通过秘密共享增强提供商间漫游的方法及其在无线局域网中的应用

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080732

Ulrike Meyer, J. Cordasco, S. Wetzel

引用次数: 14

Voice over wireless LAN: a fine-scalable channel-adaptive speech coding scheme 无线局域网语音:一种精细可扩展的信道自适应语音编码方案

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080752

Marco Zibull, André Riedel, D. Hogrefe

引用次数: 3

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots 第三届ACM无线移动应用和无线局域网热点服务国际研讨会论文集

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730

Sunghyun Choi, Millind M. Buddhikot, R. Cigno

{"title":"Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots","authors":"Sunghyun Choi, Millind M. Buddhikot, R. Cigno","doi":"10.1145/1080730","DOIUrl":"https://doi.org/10.1145/1080730","url":null,"abstract":"Welcome to the Third ACM International Workshop on Wireless Mobile Applications and Services on WLAN Hotspots (WMASH 2005). We are very pleased to present a workshop on a very hot, timely, and challenging topic. The success of WLANs is continuing, in spite of the very rapid evolution of today's wireless networks, characterized by sudden rise and fall of technologies and solutions. Today, we are witnessing a great and rising interest from both the research community and operators of public WLANs. In its third edition, WMASH promises to be an even greater success than its first two editions: the premier venue for the research community to convene and discuss technical and business challenges behind the evolution of WLAN from cable replacement to public access means.We received a total of 55 submissions from 29 countries. The workshop program includes 9 papers and 9 posters by authors from 15 countries. We regret that many high quality submissions could not be accommodated due to the space limitation. The program covers a variety of topics including mobility, location awareness, multimedia, accounting/management, and models/measurements. WMASH 2005, for the first time, includes a poster session with 9 exciting posters, and we believe that this session will foster lots of active interactions and discussions among participants. In addition to the presentation of papers/posters, the program also contains an exciting panel discussion on technical and business issues behind the evolution of WLAN hot-spots and hot-zones, in line with the tradition of the first WMASHs.","PeriodicalId":423859,"journal":{"name":"Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114352457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

WilmaGate: a new open access gateway for hotspot management WilmaGate:用于热点管理的新型开放式接入网关

Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots Pub Date : 2005-09-02 DOI: 10.1145/1080730.1080740

M. Brunato, D. Severina

{"title":"WilmaGate: a new open access gateway for hotspot management","authors":"M. Brunato, D. Severina","doi":"10.1145/1080730.1080740","DOIUrl":"https://doi.org/10.1145/1080730.1080740","url":null,"abstract":"Wireless access has already become a ubiquitous way to connect to the Internet, but the mushrooming of wireless access infrastructures throughout the world has given rise to a wide range of user authentication, authorization and accounting (AAA) mechanisms, with lots of incompatible \"standards\", each having its unique features and responding to specific problems.The WilmaGate system has been developed in order to provide a viable alternative to such a scenario. The assumptions that led to this system are very simple. First, wireless users are often already registered to some traditional access provider, or to an institution: rather than requiring a different subscription to each wireless access system, we just require the subscriber's service provider or institution to collaborate with the access system for user authentication. Second, users should not be forced to install specialized clients into their computers for two reasons: their systems would grow unstable and some types of computers (e.g., PDAs) would not be able to access the network. Third, security for e-mail and passwords is mainly provided by end-to-end protocols such as SSL and TLS, so introducing low-level authentication and encryption can be regarded as unnecessary, and causes often unnecessary overhead.In this work we oversee the system architecture, which has already been deployed, and describe its main component, the WilmaGate. A short discussion on the current system implementation and its performance is also provided.","PeriodicalId":423859,"journal":{"name":"Proceedings of the 3rd ACM international workshop on Wireless mobile applications and services on WLAN hotspots","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126980746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 21