Mobile telephony

About: Mobile telephony is a research topic. Over the lifetime, 38008 publications have been published within this topic receiving 553646 citations.

A Survey on Security Aspects for 3GPP 5G Networks

Abstract: With the continuous development of mobile communication technologies, Third Generation Partnership Project (3GPP) has proposed related standards with the fifth generation mobile communication technology (5G), which marks the official start of the evolution from the current Long Term Evolution (LTE) system to the next generation mobile communication system (5GS). This paper makes a large number of contributions to the security aspects of 3GPP 5G networks. Firstly, we present an overview of the network architecture and security functionality of the 3GPP 5G networks. Subsequently, we focus on the new features and techniques including the support of massive Internet of Things (IoT) devices, Device to Device (D2D) communication, Vehicle to Everything (V2X) communication, and network slice, which incur the huge challenges for the security aspects in 3GPP 5G networks. Finally, we discuss in detail the security features, security requirements or security vulnerabilities, existing security solutions and some open research issues about the new features and techniques in 3GPP 5G network.

A system for ensuring encrypted communication after handover

Abstract: A fraudulent intruder can eavesdrop on a call by removing information about an encryption algorithm when a multimode mobile station sends an unpro-tected initial signaling message containing this information over the radio interface to the mobile telecommunications system. The attempt can be pre-vented in a universal mobile telecommunications system (UMTS) comprising at least two radio access networks providing mobile stations with access to at least one core network, a multimode mobile station, and at least one core network. During connection setup with a first radio access network, the mul-timode mobile station sends an unprotected initial signaling message that includes information about those encryption algorithms that the multimode mobile station supports when it communicates in a second radio access network. The first radio access network saves some or all the information of it. Then it composes and sends an integrity-protected message that includes information about the encryption algorithms supported by the multimode mobile station in the second radio access network.

Towards Virtual Machine Migration in Fog Computing

Abstract: Handoff mechanisms allow mobile users to move across multiple wireless access points while maintaining their voice and/or data sessions. A traditional handoff process is concerned with smoothly transferring a mobile device session from its current access point (or cell) to a target access point (or cell). These handoff characteristics are sufficient for voice calls and background data transfers, however nowadays many mobile applications are heavily based on data and processing capabilities from the cloud. Such applications, especially those that require greater interactivity, often demand not only a smooth session transfer, but also the maintenance of quality of service requirements that impact a user's experience. In this context, the Fog Computing paradigm arises to overcome delays encountered when applications need low latency to access data or offload processing to the cloud. Fog computing introduces a distributed cloud layer, composed of cloudlets (i.e., "small clouds" with lower computational capacity), between the user and the cloud. Cloudlets allow low latency access to data or processing capabilities, which can be accomplished by offering a VM to the user. An overview of Fog computing is first providing, relating it to general concepts in Cloud-based systems, followed by a general architecture to support virtual machine migration in this emerging paradigm -- discussing both the benefits and challenges associated with such migration.

Effects of Hand Phantom on Mobile Phone Antenna Performance

Abstract: With the continuous trend to smaller mobile devices with more functionality and more wireless bands, the possible insufficient over-the-air (OTA) becomes a growing concern for service providers. In addition to reduced radiation efficiency by smaller antennas in smaller phones, the head and in particular the hand may further impair radiation performance. The aim of this paper is to investigate the influence of the various parameters of the hand upon the OTA performance criteria to support the standardization process of the hand phantom and to provide the tools for optimization of handheld transmitters. The results reveal the following order of significance for small variations in hand parameters: 1) position of index finger; 2) distance between phone case and palm; 3) position of the other fingers; 4) size of the hand; 5) dielectric parameters; 6) wrist length and tilt. Some configurations may lead to a slight increase of the peak spatial SAR in the head. OTA assessment without the hand does not provide a good measure of phone performance in real life. However, good reproducibility of evaluations requires a precise definition of the hand, in particular its geometry and the phone position within the hand.

Vita: A Crowdsensing-Oriented Mobile Cyber-Physical System

Abstract: As a prominent subcategory of cyber-physical systems, mobile cyber-physical systems could take advantage of widely used mobile devices, such as smartphones, as a convenient and economical platform that facilitates sophisticated and ubiquitous mobile sensing applications between humans and the surrounding physical world. This paper presents Vita, a novel mobile cyber-physical system for crowdsensing applications, which enables mobile users to perform mobile crowdsensing tasks in an efficient manner through mobile devices. Vita provides a flexible and universal architecture across mobile devices and cloud computing platforms by integrating the service-oriented architecture with resource optimization mechanism for crowdsensing, with extensive supports to application developers and end users. The customized platform of Vita enables intelligent deployments of tasks between humans in the physical world, and dynamic collaborations of services between mobile devices and cloud computing platform during run-time of mobile devices with service failure handling support. Our practical experiments show that Vita performs its tasks efficiently with a low computation and communication overhead on mobile devices, and eases the development of multiple mobile crowdsensing applications and services. In addition, we present a mobile crowdsensing application, Smart City, developed on Vita to demonstrate the functionalities and practical usage of Vita.