Middleware models for location-based services: a survey
---
paper_title: Location-Based Services: Fundamentals and Operation

paper_content:

Preface. List of Abbreviations. 1 Introduction. 1.1 What are Location-based Services? 1.2 Application Scenarios. 1.3 LBS Actors. 1.4 Standardization. 1.5 Structure of this Book. Part I: Fundamentals. 2 What is Location? 2.1 Location Categories. 2.2 Spatial Location. 2.3 Conclusion. 3 Spatial Databases and GIS. 3.1 What are Spatial Databases and GIS? 3.2 Geographic versus Spatial Data Models. 3.3 Representing Spatial Objects. 3.4 Features and Themes. 3.5 Algorithms of Computational Geometry. 3.6 Geography Markup Language. 3.7 Conclusion. 4 Basics of Wireless Communications. 4.1 Signals. 4.2 Propagation of Radio Signals. 4.3 Multiplexing and Multiple Access. 4.4 Conclusion. 5 Cellular Networks and Location Management. 5.1 Overview of Cellular Systems. 5.2 Principles of Cellular Networks. 5.3 Mobility Management. 5.4 Common Concepts of Location Management. 5.5 Location Management in CS Networks. 5.6 Location Management in PS Networks. 5.7 Conclusion. Part II: Positioning. 6 Fundamentals of Positioning. 6.1 Classification of Positioning Infrastructures. 6.2 Basic Positioning Methods. 6.3 Range Measurements. 6.4 Accuracy and Precision. 6.5 Error Sources. 6.6 Conclusion. 7 Satellite Positioning. 7.1 Historical Background. 7.2 Orbital Motion of Satellite Systems. 7.3 Global Positioning System. 7.4 Differential GPS. 7.5 Galileo. 7.6 Conclusion. 8 Cellular Positioning. 8.1 Positioning in GSM Networks. 8.2 Positioning in UMTS Networks. 8.3 Assisted GPS in GSM and UMTS. 8.4 Positioning in other Cellular Systems. 8.5 Conclusion. 9 Indoor Positioning. 9.1 WLAN Positioning. 9.2 RFID Positioning. 9.3 Indoor Positioning with GPS. 9.4 Non Radiolocation Systems. 9.5 Conclusion. Part III: LBS Operation. 10 Interorganizational LBS Operation. 10.1 LBS Supply Chain. 10.2 Scenarios of the LBS Supply Chain. 10.3 Supplier/Consumer Patterns for Location Dissemination. 10.4 Privacy Protection. 10.5 Conclusion. 11 Architectures and Protocols for Location Services. 11.1 GSMand UMTS Location Services. 11.2 Enhanced Emergency Services. 11.3 Mobile Location Protocol. 11.4 WAP Location Framework. 11.5 Parlay/OSA. 11.6 Geopriv. 11.7 Conclusion. 12 LBS Middleware. 12.1 Conceptual View of an LBS Middleware. 12.2 Location API for J2ME. 12.3 OpenGIS Location Services. 12.4 Conclusion. 13 LBS - The Next Generation. Bibliography. Index.
---
paper_title: LighTS: a lightweight, customizable tuple space supporting context-aware applications

paper_content:

The tuple space model inspired by Linda has recently been rediscovered by distributed middleware. Moreover, some researchers also applied it in the challenging scenarios involving mobility and more specifically context-aware computing. Context information can be stored in the tuple space, and queried like any other data.Nevertheless, it turns out that conventional tuple space implementations fall short of expectations in this new domain. On one hand, many of the available systems provide a wealth of features, which make the resulting implementation unnecessarily bloated and incompatible with the tight resource constraints typical of this field. Moreover, the traditional Linda matching semantics based on value equality are not appropriate for context-aware computing, where queries are often formulated over value ranges, and where there is a prominent need to deal with imprecise information coming from multiple sources.In this paper, we describe a new tuple space implementation called LIGHTS. Originally developed as the tuple space core of the LIME [11] system, LIGHTS provides a flexible framework that makes it easy to introduce extensions to the tuple space and in general to customize the tuple space implementation. The design and programming interface of LIGHTS is presented, and its flexibility demonstrated by illustrating extensions that proved useful in the development of context-aware applications.
---
paper_title: LighTS: a lightweight, customizable tuple space supporting context-aware applications

paper_content:

The tuple space model inspired by Linda has recently been rediscovered by distributed middleware. Moreover, some researchers also applied it in the challenging scenarios involving mobility and more specifically context-aware computing. Context information can be stored in the tuple space, and queried like any other data.Nevertheless, it turns out that conventional tuple space implementations fall short of expectations in this new domain. On one hand, many of the available systems provide a wealth of features, which make the resulting implementation unnecessarily bloated and incompatible with the tight resource constraints typical of this field. Moreover, the traditional Linda matching semantics based on value equality are not appropriate for context-aware computing, where queries are often formulated over value ranges, and where there is a prominent need to deal with imprecise information coming from multiple sources.In this paper, we describe a new tuple space implementation called LIGHTS. Originally developed as the tuple space core of the LIME [11] system, LIGHTS provides a flexible framework that makes it easy to introduce extensions to the tuple space and in general to customize the tuple space implementation. The design and programming interface of LIGHTS is presented, and its flexibility demonstrated by illustrating extensions that proved useful in the development of context-aware applications.
---

Title: Middleware models for location-based services: a survey

Section 1: INTRODUCTION
Description 1: This section introduces the concept of Location-Based Services (LBS), their characteristics, and sets the scope for the middleware models discussed in the paper.

Section 2: LBS Application Characteristics
Description 2: This section details the types of LBS applications and extracts the main characteristics and requirements for middleware.

Section 3: LBS Middleware characteristics
Description 3: This section defines the requirements and characteristics of middleware platforms that support LBS applications.

Section 4: Middleware Models for LBS
Description 4: This section presents various middleware models used for LBS, including their characteristics and how they support different LBS applications.

Section 5: Publish/Subscribe Models
Description 5: This subsection describes publish/subscribe middleware models and their application in LBS.

Section 6: Subject Space Models
Description 6: This subsection explains subject space models, including their representation, regions, and how they apply to LBS.

Section 7: Tuple Space Models
Description 7: This subsection outlines tuple space models, detailing their advantages and application to LBS environments.

Section 8: Tuple space modelling for LBS
Description 8: This subsection discusses the application and adaptation of tuple space models specifically for LBS environments.

Section 9: Conclusion and future work
Description 9: This section summarizes the findings of the survey and suggests areas for future research in the development and standardization of LBS middleware models.