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Showing papers on "Roaming published in 2004"


Book
01 Jan 2004
TL;DR: Ling et al. as mentioned in this paper examined the once unexpected interaction between humans and cell phones, and between humans, period, based on world-wide research involving tens of thousands of interviews and contextual observations, looked into the impact of the phone on our daily lives.
Abstract: Has the cell phone forever changed the way people communicate? The mobile phone is used for “real time” coordination while on the run, adolescents use it to manage their freedom, and teens “text” to each other day and night. The mobile phone is more than a simple technical innovation or social fad, more than just an intrusion on polite society. This book, based on world-wide research involving tens of thousands of interviews and contextual observations, looks into the impact of the phone on our daily lives. The mobile phone has fundamentally affected our accessibility, safety and security, coordination of social and business activities, and use of public places. Based on research conducted in dozens of countries, this insightful and entertaining book examines the once unexpected interaction between humans and cell phones, and between humans, period. The compelling discussion and projections about the future of the telephone should give designers everywhere a more informed practice and process, and provide researchers with new ideas to last years. *Rich Ling (an American working in Norway) is a prominent researcher, interviewed in the new technology article in the November 9 issue of the New York Times Magazine. *A particularly "good read", this book will be important to the designers, information designers, social psychologists, and others who will have an impact on the development of the new third generation of mobile telephones. *Carefully and wittily written by a senior research scientist at Telenor, Norway's largest telecommunications company, and developer of the first mobile telephone system that allowed for international roaming. Table of Contents Preface Acknowledgments Chapter 1: Introduction Chapter 2: Making Sense of Mobile Telephone Adoption Chapter 3: Safety and Security Chapter 4: The Coordination of Everyday Life Chapter 5: The Mobile Telephone and Teens Chapter 6: The Intrusive Nature of Mobile Telephony Chapter 7: Texting and the Growth of Asynchronous Discourse Chapter 8: Conclusion: The Significance of Osborne's Prognosis Appendix Endnotes Bibliography Index

898 citations


Patent
Stefan Scheinert1, Peter Lange1
06 Aug 2004
TL;DR: In this paper, the Internet System Manager (iSM) automatically configures and integrates the radio base station into the network by defining configuration parameter settings that allow fill interoperation of the base station with the network, with regards to roaming and handover.
Abstract: A radio base station in a mobile communication network collects information about the network and exchanges data with a configuration device, the Internet System Manager (iSM). The iSM automatically configures and integrates the base station into the network by defining configuration parameter settings that allow fill interoperation of the base station with the network, with regards to roaming and handover in particular, without the need to add or modify parameter settings in other existing network elements. A very large number and high geographical density of such base stations is supported with full interoperation between them, allowing to overcome limitations of conventional mobile communication networks in this regard, by utilizing a certain combination of parameter settings and a new method to address the different base stations in the network.

269 citations


Patent
13 Aug 2004
TL;DR: In this paper, a method and apparatus for mobile communication in multiple mobile communications networks is presented, where the SIM is used to receive and place calls while the user is in the user's home network and while a user is roaming in another network.
Abstract: A method and apparatus for mobile communication in multiple mobile communications networks. Embodiments include installing a SIM that includes at least one IMSI and at least one MSISDN in a mobile communications device. The SIM is used to receive and place calls while the user is in the user's home network and while the user is roaming in another network. In various embodiments, one of a home MSISDN and a local MSISDN is used.

239 citations


Proceedings ArticleDOI
20 Jun 2004
TL;DR: A load-balancing scheme for overlapping wireless LAN cells that increases the total wireless network throughput and decreases the cell delay and the load metric is the access point throughput.
Abstract: We propose a load-balancing scheme for overlapping wireless LAN cells. Agents running in each access point broadcast periodically the local load level via the Ethernet backbone and determines whether the access point is overloaded, balanced or under-loaded by comparing it with the received reports. The load metric is the access point throughput. Overloaded access points force the handoff of some stations to balance the load. Only the under-loaded access points accept the roaming stations in minimizing the number of handoffs. We show via experimental evaluation that our balancing scheme increases the total wireless network throughput and decreases the cell delay.

231 citations


Journal ArticleDOI
TL;DR: A novel seamless and proactive end- to-end mobility management system, which can maintain the connections based on the end-to-end principle by incorporating an intelligent network status detection mechanism.
Abstract: Roaming across heterogeneous wireless networks such as wireless wide area network (WWAN) and wireless local area network (WLAN) poses considerable challenges, as it is usually difficult to maintain the existing connections and guarantee the necessary quality-of-service. This paper proposes a novel seamless and proactive end-to-end mobility management system, which can maintain the connections based on the end-to-end principle by incorporating an intelligent network status detection mechanism. The proposed system consists of two components, connection manager (CM) and virtual connectivity (VC). The CM, by using novel media access control-layer and physical-layer sensing techniques, can obtain accurate network condition, while at the same time reducing the unnecessary handoff and ping-pong effect. The VC can make mobility transparent to applications without additional network-layer infrastructure support using a local connection translation, and can handle mobility well in the network address translator and simultaneous movement cases using a subscription/notification service. The proposed system enjoys several unique advantages: 1) capable of reacting to roaming events proactively and accurately; 2) maintaining the connection's continuity with small handoff delay; and 3) being a unified end-to-end approach for both IPv4 and IPv6 networks. We have built a prototype system and performed experiments to demonstrate the advantages of the proposed system.

224 citations


Journal ArticleDOI
Apostolis K. Salkintzis1
TL;DR: This article proposes and discusses some novel architectures able to provide internetworking between WLAN and 3G networks, and meet the requirements of the most common internetworking scenarios.
Abstract: The intense wireless LAN standardization and R&D activities worldwide, combines with the recent successful deployment of WLANs, provide prime evidence that WLAN technology will play a key role in the fourth generation of mobile data networks. In this context, there is a strong need to integrate WLANs with 3G mobile data networks and develop hybrid mobile data networks capable of ubiquitous data services and very high data rates in strategic locations. This article addresses this need by proposing and discussing some novel architectures able to provide internetworking between WLAN and 3G networks, and meet the requirements of the most common internetworking scenarios. These architectures can enable 3G subscribers to benefit from high-throughput IP connectivity in hotspots and also to attain service roaming across several radio access technologies, such as IEEE 802.11, HiperLan/2, ULTRAN, and GERAN.

213 citations



Journal ArticleDOI
TL;DR: In this paper, a mobile agent is proposed to track the roaming path of a moving object in WSNs. And the agent is mobile since it will choose the sensor closest to the object to stay.
Abstract: The wireless sensor network is an emerging technology that may greatly facilitate human life by providing ubiquitous sensing, computing, and communication capability, through which people can more closely interact with the environment wherever he/she goes. To be context-aware, one of the central issues in sensor networks is location tracking, whose goal is to monitor the roaming path of a moving object. While similar to the location-update problem in PCS networks, this problem is more challenging in two senses: (1) there are no central control mechanism and backbone network in such environment, and (2) the wireless communication bandwidth is very limited. In this paper, we propose a novel protocol based on the mobile agent paradigm. Once a new object is detected, a mobile agent will be initiated to track the roaming path of the object. The agent is mobile since it will choose the sensor closest to the object to stay. The agent may invite some nearby slave sensors to cooperatively position the object and inhibit other irrelevant (i.e., farther) sensors from tracking the object.As a result, the communication and sensing overheads are greatly reduced. Our prototyping of the location-tracking mobile agent based on IEEE 802.11b NICs and our experimental experiences are also reported.

186 citations


Journal ArticleDOI
TL;DR: A novel integrated WWAN/WLAN two-hop-relay architecture is proposed that both enhances the system capacity of existing WWAN systems and extends the system coverage of WLAN terminals.
Abstract: Next-generation wireless systems (4G and beyond) are envisioned to provide ubiquitous high-speed access over heterogeneous radio technologies. The integration of cellular WWANs and WLANs has drawn considerable attention from the research and commercial communities (e.g., 3G+802.11). Emerging dualmode mobile terminals could provide flexibility and system performance enhancement by providing seamless roaming between WWANs and WLANs. In this article we propose a novel integrated WWAN/WLAN two-hop-relay architecture that both enhances the system capacity of existing WWAN systems and extends the system coverage of WLAN terminals. The proposed two-hop-relay architecture can be considered as a system-level macro diversity technique that utilizes temporal channel quality variation to achieve increased system capacity. Significant capacity gain is achieved with the proposed twohop-relay architecture in both a fixed-rate uplink CDMA system and a variable data rate downlink HDR-like system.

182 citations


Patent
23 Mar 2004
TL;DR: In this article, a remote preference unit for influencing visited network selection by roaming mobile units, comprises a detection signaling relay/probe on International signaling connections, for detection of roaming activity by mobile units and a database indicative of preferred networks in the given country that the network operator prefers his roamers to use, determining the output, and an output unit associated with said detection probe and said database to output indications.
Abstract: A remote preference unit for influencing visited network selection by roaming mobile units, comprises a detection signaling relay/probe on International signaling connections, for detection of roaming activity by mobile units, a database indicative of preferred networks in the given country that the network operator prefers his roamers to use, application logic with certain criteria, determining the output, and an output unit, associated with said detection probe and said database to output indications to influence network selection by said detected roaming mobile units. In one embodiment the output is simply a rejection of the location update signal that forms the roaming request. In an alternative embodiment the signal is a copy of the relevant section of the database which is uploaded to the SIM card of the roaming unit. The SIM card upgrade may or may not be accompanied by a stage of forcing the handset to re-initiate the network selection process.

176 citations


Patent
29 Jan 2004
TL;DR: In this paper, a system and method for improved vertical handoff between different types of wireless network is proposed. But the authors focus on the quality of service (QoS) of mobile devices roaming between different wireless networks.
Abstract: A system and method for improved vertical handoff between different types of wireless network. Network allocation vector occupation and packet collision probability are used as quality of service measures, enabling vertical handoffs to be delayed until actually beneficial to quality of service. Improved wireless network cell boundary detection in vertical handoff scenarios is achieved with a Fourier-based technique in conjunction with an adaptively determined minimum operating signal strength threshold. Improved wireless network cell boundary detection enables vertical handoffs from high quality of service networks to be delayed as long as possible. Together, practical wireless network quality of service measures and improved detection of wireless network cell boundaries in vertical handoff scenarios reduce the rate of unnecessary vertical handoff resulting in higher overall quality of service experienced by a mobile computing device roaming between wireless network types.

Patent
14 Jan 2004
TL;DR: In this paper, a roaming service method for a fast and secure wireless network is provided, where an AP which an STA associates with transmits proactive keys needed for roaming to neighbor APs of the AP.
Abstract: A roaming service method for a fast and secure wireless network is provided. In an embodiment of the present invention, an AP, which an STA associates with, transmits proactive keys needed for roaming to neighbor APs of the AP. When the STA moves to one of the neighbor APs, a reassociation is carried out between the STA and the neighbor AP using the already provided proactive key. In another embodiment of the present invention, an authentication server transmits proactive keys needed for roaming to neighbor APs to which the STA is likely to move, so that when the STA moves to one of the neighbor APs, a reassociation is carried out between the STA and the neighbor AP using the already provided proactive key.

Patent
04 Mar 2004
TL;DR: A system, method and apparatus for providing location services whereby location determination (130) and location disclosure (120) are treated as separate and independent processes or LCS-sessions is described in this article.
Abstract: A system, method and apparatus for providing location services whereby location determination (130) and location disclosure (120) are treated as separate and independent processes or LCS-sessions. Location determination may be performed (as necessary) via a first set of network entities (256, 218, 260) to obtain location information for a mobile station. The location information may be cached for subsequent disclosure to any number of applications. Location disclosure may be performed (when requested) via a second set of network entities (256, 218, 216) to provide the location information. Location determination may utilize a first security procedure for authentication and authorization and to obtain a first session key used for location determination. Location disclosure may utilize a second security procedure for authentication and authorization and to obtain a second session key used for location disclosure. For a roaming mobile station, location determination may be performed via a serving network and location disclosure may be performed via a home network.

Proceedings ArticleDOI
26 Sep 2004
TL;DR: This paper statistically characterize both static flows and roaming flows in a large campus wireless network using a recently-collected trace and discovers that the static flow arrivals in spatial proximity show strong similarity.
Abstract: Several studies have recently been performed on wireless university campus networks, corporate and public networks. Yet little is known about the flow-level characterization in such networks. In this paper, we statistically characterize both static flows and roaming flows in a large campus wireless network using a recently-collected trace. For static flows, we take a two-tier approach to characterizing the flow arrivals, which results a Weibull regression model. We further discover that the static flow arrivals in spatial proximity show strong similarity. As for roaming flows, they can also be well characterized statistically.We explain the results by user behaviors and application demands, and further cross-validate the modeling results by three other traces. Finally, we use two examples to illustrate how to apply our models for performance evaluation in the wireless context.

Patent
Johan Rune1
08 Oct 2004
TL;DR: In this paper, the home network assisted selection of an intermediary service network for a roaming mobile terminal is disclosed, based on a list of desired intermediary service networks generated using information associated with the mobile terminal's home service network.
Abstract: Home network-assisted selection of an intermediary service network for a roaming mobile terminal is disclosed. The selection is based on a list of desired intermediary service networks generated using information associated with the mobile terminal's home service network. In one example embodiment, the list is provided to a central access server, which provides this information to a local access network to which the mobile terminal is requesting access. The local access network selects one of the networks included on the list of desired intermediary service networks obtained from the central access server. This example embodiment uses existing protocols without modification, and can be used in conjunction with other intermediary service network selection procedures, if desired.

Patent
24 Nov 2004
TL;DR: In this article, the authors propose an apparatus and method of client device roaming from a home subnet to a foreign subnet of a network by maintaining a fixed client IP address, default gateway IP address and IP subnet attachment as the client device roams from the first access node to the second access node.
Abstract: Disclosed is an apparatus and method of client device roaming from a home subnet to a foreign subnet of a network. The method includes the client device accessing the network through a first access node of the home subnet, and the client device roaming to a second access node of the foreign subnet, the client device accessing the network through the second access node, the client device maintaining a fixed client IP address, default gateway IP address and IP subnet attachment as the client device roams from the first access node to the second access node.

Proceedings ArticleDOI
19 Sep 2004
TL;DR: This work proposes exploiting the distinct cyclostationary properties of signals from different air interfaces as features for air interface recognition, providing a seamless interoperability between different air interface standards and an enhanced roaming capability.
Abstract: Reconfigurable software radio equipment is seen as the next evolutionary step in mobile communications One of the most important properties of a software radio terminal is that it is capable of using a wide range of air interface standards, providing a seamless interoperability between different air interface standards and an enhanced roaming capability This multimode operation has to be supported by a number of key functionalities, one of which is the air interface recognition A software radio terminal has to be able to detect, recognize and monitor the air interfaces available in the frequency environment In our work, we propose exploiting the distinct cyclostationary properties of signals from different air interfaces as features for air interface recognition

Patent
27 May 2004
TL;DR: In this paper, a method and system for pre-authenticating a pre-establishing key management on a roaming device prior to reassociation to facilitate fast hand-off in a wireless network is described.
Abstract: A method and system for pre-authenticating a pre-establishing key management on a roaming device (10) prior to reassociation to facilitate fast hand-off in a wireless network is described. For enhanced mobility, both authentication and key establishment is performed prior to reassociation of the roaming device (10) between access points (12). When the roaming device enters in contact with one of the access points, a local authentication is performed between the access point and the roaming device prior to reassociation with the access point to allow for fast hand-offs of the device between access points within the network.

Patent
02 Dec 2004
TL;DR: In this article, a location system is enabled to automatically fall back to a message tunneling mechanism to ensure the security of a communication path between the location service system and the target wireless device, ensuring that the communication path is uninterrupted as the wireless device travels.
Abstract: An improved User Plane location based service (LBS) architecture and message flow, enabling seamless User Plane location based services even when a mobile or wireless device has roamed among different carrier networks. The present invention overcomes constraints inherent in the current protocol for roaming support defined by the Secure User Plane Location Service specification. A location system is enabled to automatically fall back to a message tunneling mechanism to ensure the security of a communication path between the location service system and the target wireless device, ensuring that the communication path is uninterrupted as the wireless device travels.

Patent
07 Apr 2004
TL;DR: In this paper, a system for authentication and authorization of a mobile terminal roaming to or in a foreign network different from its home network is provided, with the home network having an authentication-and authorization home server (AAAH), and the foreign network having a plurality of domains each of which comprises at least one local server for authentication, authorization and accounting.
Abstract: A apparatus, system, and network elements for authentication and authorization of a mobile terminal (MT) roaming to or in a foreign network different from its home network is provided, the home network having an authentication and authorization home server (AAAH), and the foreign network having a plurality of domains each of which comprises at least one local server (AAAL1, AAAL2) for authentication, authorization and accounting, each of which local servers being connected to at least one network access server (NAS) for handling access for mobile terminals roaming to or in the foreign network, wherein an authentication and authorization of the mobile terminal is performed whenever the mobile terminal performs a roaming, wherein the authentication and authorization is performed according to a procedure pursuant to one of a plurality of hierarchy levels, whereby a combination of network elements involved in the roaming determines the hierarchy level to be used.

Patent
28 Jan 2004
TL;DR: In this paper, the authors proposed a public access network roaming system, which is accomplished in one or more embodiments by requiring no new software or hardware to be installed by the end user.
Abstract: Disclosed embodiments significantly increase the power and flexibility of public access network roaming systems. This is accomplished in one or more embodiments by requiring no new software or hardware to be installed by the end user. Further, an end user's service provider can be automatically determined. If a pre-negotiated network sharing agreement does not exist between the network provider (7) and service provider (7), a network sharing agreement can be dynamically facilitated, even if the network provider (7) and the service provider (2) have no prior business relationship, while protecting the business and financial interests of both providers.

Proceedings ArticleDOI
01 Oct 2004
TL;DR: An overview of fast authentication methods when roaming within or across IEEE 802.11 Wireless-LANs is presented and a number of possible changes to these solutions (typically in terms of network architectures and/or required trust relationships) for inter-domain operation are proposed.
Abstract: Improving authentication delay is a key issue for achieving seamless handovers across networks and domains. This paper presents an overview of fast authentication methods when roaming within or across IEEE 802.11 Wireless-LANs. Besides this overview, the paper analyses the applicability of IEEE 802.11f and Seamoby solutions to enable fast authentication for inter-domain handovers. The paper proposes a number of possible changes to these solutions (typically in terms of network architectures and/or required trust relationships) for inter-domain operation. In addition, the paper identifies the crucial research issues therein. Possible solutions and directions for future research include: update to security infrastructure, inter-layer communication and discovery of appropriate networks.

Patent
01 Apr 2004
TL;DR: In this article, the authors propose a seamless vertical handoff method that allows the network applications and connections on a mobile node to continue without disruption as it moves within a wireless overlay network that comprises multiple possibly overlapping layers of wireless networks with different underlying technologies, providing mobile roaming capabilities.
Abstract: A seamless vertical handoff method allows the network applications and connections on a mobile node to continue without disruption as it moves within a wireless overlay network that comprises multiple possibly overlapping layers of wireless networks (e.g., a WLAN and a WWAN) with different underlying technologies, providing mobile roaming capabilities. The method comprises a WLAN access point signal strength monitor for determining when to switch between WLAN and WWAN, and a network connection migration scheme that can move an active network connection from a wireless link of one technology to another wireless link of a different technology in a way that is transparent to the user, the remote end of the network connection, and the operator of the WWAN carrier.

Patent
13 Feb 2004
TL;DR: In this paper, a method and system for roaming mobile communications between networks is described, which includes a plurality of messages from a home network subscriber device that is device is roaming outside the home network.
Abstract: A method and system for roaming mobile communications between networks is described. One embodiment includes a plurality of messages from a home network subscriber device that is device is roaming outside the home network. A communications link is established with a destination network, including modifying at least one of the messages such that the message appears to the destination network to originate from a partner network of the destination network. Both voice and data are transmitted via the communications link.

Patent
23 Feb 2004
TL;DR: In this paper, a roam request sent by a switch corresponding to the user's new location may be received by the other switches in the network, if the user is known to any of these switches, then they may execute steps to accommodate the roaming.
Abstract: Wireless roaming in a computer network may be handled through a solution provided on one or more switches in the network. A roam request sent by a switch corresponding to the user's new location may be received by the other switches in the network. If the user is known to any of these switches, then they may execute steps to accommodate the roaming. The tasks performed may vary based on whether the roaming is on layer 2 or layer 3, whether the switch is a home agent for the client, and/or whether the switch already corresponds to the user's new location.

Patent
Steven I. Carlson1, Scott E. Riffe1
14 Jun 2004
TL;DR: In this paper, a second switch receives an indication from a roaming network that a call forwarded by the roaming network has been dropped by roaming network, and in response to receiving the indication, forwards the call from a first switch.
Abstract: A second switch receives an indication from a roaming network that a call forwarded by the roaming network has been dropped by the roaming network, and in response to receiving the indication, forwards the call from a first switch.

Patent
27 Jul 2004
TL;DR: In this article, a method of displaying location data representing a mobile phone's current approximate location to a user via the mobile phone display is presented, where the location information is iconically displayed and periodically updated.
Abstract: A method of presenting location data representing a mobile phone's current approximate location to a mobile phone user via the mobile phone display. The location information is iconically displayed and periodically updated. To display location information, the mobile phone determines its current position. Once the current position is determined, the mobile phone looks up locations within a predetermined distance from the current position of the mobile phone. The mobile phone then compares the results and selects the location/location icon pairing that is closest to the current position of the mobile phone. This location icon is then displayed on the mobile phone display. The mobile phone then waits a predetermined period before re-determining the current position of the mobile phone and repeating the search/display processes. Both the predetermined wait period and predetermined distance from the current position are user defined parameters that can be altered at the user's discretion.

Proceedings ArticleDOI
31 Oct 2004
TL;DR: In this article, a human trust management model and framework that facilitates the construction of trust-aware mobile systems and applications is presented. But, the model is not suitable for mobile ad hoc environments.
Abstract: Rapid advances in wireless networking technologies have enabled mobile devices to be connected anywhere and anytime While roaming, applications on these devices dynamically discover hosts and services with whom interactions can be started However, the fear of exposure to risky transactions with potentially unknown entities may seriously hinder collaboration To minimise this risk, an engineering approach to the development of trust-based collaborations is necessary This paper introduces hTrust, a human trust management model and framework that facilitates the construction of trust-aware mobile systems and applications In particular, hTrust supports: reasoning about trust (trust formation), dissemination of trust information in the network (trust dissemination), and derivation of new trust relationships from previously formed ones (trust evolution) The framework views each mobile host as a self-contained unit, carrying along a portfolio of credentials that are used to prove its trustworthiness to other hosts in an ad-hoc mobile environment Customising functions are defined to capture the natural disposition to trust of the user of the device inside our trust management framework

Patent
Johan Rune1
08 Oct 2004
TL;DR: In this paper, a roaming mobile terminal determines if a local access network is associated with the mobile's home service network, and if not, the mobile terminal sends a list of intermediary service networks to the local access networks.
Abstract: Terminal-assisted selection of intermediary network for a roaming mobile terminal is disclosed. The mobile terminal determines if a local access network is associated with the mobile's home service network. If not, or if the mobile terminal cannot determine whether the local access network is associated with its home service network, the mobile terminal sends a list of intermediary service networks to the local access network. The local access network can select one of the intermediary service networks to be used in an authentication procedure between the mobile terminal the home service network.

Patent
25 Jun 2004
TL;DR: In this article, a location based service provider (LBSP) that is outside of the serving network receives from the serving system an MST-initiated request for LBSs and an identifier of a first location system (LS1).
Abstract: A method and system for providing location based services (LBSs) to a mobile-subscriber terminal (MST) roaming in a serving network is provided. A location based service provider (LBSP) that is outside of the serving network receives from the serving system an MST-initiated request for LBSs and an identifier of a first location system (LS1) that is associated with the serving network. Responsive to the MST-initiated request, the LBSP sends to a second location system (LS2) (i) a request for mobile positioning information (MPI) for the MST, and (ii) the identifier. Using the identifier, the LS2 addresses and sends the request for MPI to the LS1. Responsively, the LS1 populates a shared database with the MPI. The LS2 retrieves the MPI from the shared database and sends it to the LBSP. The LBSP sends to the MST a reply to the MST-initiated request for LBSs.