A Survey on Handover Management in Mobility Architectures

This work presents a comprehensive and structured taxonomy of available techniques for managing the handover process in mobility architectures. Representative works from the existing literature have been divided into appropriate categories, based on their ability to support horizontal handovers, vertical handovers and multihoming. We describe approaches designed to work on the current Internet (i.e. IPv4-based networks), as well as those that have been devised for the "future" Internet (e.g. IPv6-based networks and extensions). Quantitative measures and qualitative indicators are also presented and used to evaluate and compare the examined approaches. This critical review provides some valuable guidelines and suggestions for designing and developing mobility architectures, including some practical expedients (e.g. those required in the current Internet environment), aimed to cope with the presence of NAT/firewalls and to provide support to legacy systems and several communication protocols working at the application layer

A generic communication architecture for end to end mobility management in the Internet

The proliferation of laptops, cellular phones, and other mobile computing platforms connected to the Internet has triggered numerous research works into mobile networking. The increasingly dense set of wireless access networks that can be potentially accessed by mobile users open the door to an era of pervasive computing. However, the puzzle of wireless access networks that tends to become the natural access networks to the Internet pushes legacy“wireoriented” communication architectures to their limit. Indeed, there is a critical gap between the increasingly used stream centric multimedia applications and the incapacity of legacy communication stacks to insure the continuity of these multimedia sessions for mobile users. This paper proposes a generic communication architecture (i.e. not dedicated to a specific protocol or technology) that aims to fill the gap between the application layer continuity needs and the discontinuity of the communication service inherent to the physical layer of wireless mobile networks. This paper introduces an end to end communication architecture that preserves efficiently session continuity in the context of mobile and wireless networks. This architecture is mainly based on end to end mechanisms that could be integrated into a new generation reconfigurable transport protocol. The proposed contribution efficiently satisfies mobility requirements such as efficient location management, fast handover, and continuous connection support

Location Management in a Transport Layer Mobility Architecture

Mobility architectures that place complexity in end nodes rather than in the network interior have many advantageous properties and are becoming popular research topics. Such architectures typically push mobility support into higher layers of the protocol stack than network layer approaches like Mobile IP. The literature is ripe with proposals to provide mobility services in the transport, session, and application layers. In this paper, we focus on a mobility architecture that makes the most significant changes to the transport layer. A common problem amongst all mobility protocols at various layers is location management, which entails translating some form of static identifier into a mobile node's dynamic location. Location management is required for mobile nodes to be able to provide globally-reachable services on-demand to other hosts. In this paper, we describe the challenges of location management in a transport layer mobility architecture, and discuss the advantages and disadvantages of various solutions proposed in the literature. Our conclusion is that, in principle, secure dynamic DNS is most desirable, although it may have current operational limitations. We note that this topic has room for further exploration, and we present this paper largely as a starting point for comparing possible solutions

Mobile Communication with Virtual Network Address Translation

Virtual Network Address Translation (VNAT) is a novel architecture that allows transparent migration of end-to-end live network connections associated with various computation units. Such computation units can be either a single process, or a group of processes of an application, or an entire host. VNAT virtualizes network connections perceived by transport protocols so that identification of network connections is decoupled from stationary hosts. Such virtual connections are then remapped into physical connections to be carried on the physical network using network address translation. VNAT requires no modification to existing applications, operating systems, or protocol stacks. Furthermore, it is fully compatible with the existing communication infrastructure; virtual and normal connections can coexist without interfering each other. VNAT functions entirely within end systems and requires no third party proxies. We have implemented a VNAT prototype with the Linux 2.4 kernel and demonstrated its functionality on a wide range of popular real-world network applications. Our performance results show that VNAT has essentially no overhead except when connections are migrated, in which case the overhead of our Linux prototype is less than 7 percent

SockMi: a solution for migrating TCP/IP connections

SockMi is a solution for the migration of TCP/IP con-nections between Linux systems. Only the migrating peer of the connection needs to reside on a Linux system. The mi-gration is completely transparent to the other peer that can reside on a system running any operating system. Our solution does not require changes to existing Linux ker-nel data structures and algorithms and can be activated in any phase of the connection. Both 2.4 and 2.6 versions of the Linux kernel are supported. 1

SIGMA: A mobility architecture for terrestrial and space networks.

Internet Protocol (IP) mobility can be handled at different layers of the protocol stack. Mobile IP has been developed to handle mobility of Internet hosts at the network layer. Mobile IP suffers from a number of drawbacks such as the requirement for infrastructure change, high handover latency, high packet loss rate, and conflict with network security solutions. As an alternative solution, a few transport layer mobility protocols have been proposed in the context of Transmission Control Protocol (TCP), for example, MSOCKS and TCP connection migration. In this dissertation, a S&barbelow; eamless I&barbelow; P-diversity-based G&barbelow; eneralized M&barbelow; obility Architecture (SIGMA) is described. SIGMA works at the transport layer and utilizes IP diversity to achieve seamless handover, and is designed to solve many of the drawbacks of Mobile IP. It can also cooperate with normal IPv4 or IPv6 infrastructure without the support of Mobile IP. The handover performance, signaling cost, and survivability issues of SIGMA are evaluated and compared with those of Mobile IP. A hierarchical location management scheme for SIGMA is developed to reduce the signaling cost of SIGMA, which is also useful to other transport layer mobility solutions. SIGMA is shown to be also applicable to managing satellite handovers in space. Finally, the interoperability between SIGMA and existing Internet security mechanisms is discussed

Design and development of a software architecture for seamless vertical handover in mobile communications

In this work I firstly present an overview on current wireless technology and network mobility focusing on challenges and issues which arise when mobile nodes migrate among different access networks, while employing real-time communications and services. In literature many solutions propose different methods and architectures to enhance vertical handover, the process of transferring a network communication between two technologically different points of attachment. After an extensive review of such solutions this document describes my personal implementation of a fast vertical handover mechanism for Android smartphones. I also performed a reliability and performance comparison between the current Android system and my enhanced architecture which have both been tested in a scenario where vertical handover was taking place between WiFi and cellular network while the mobile node was using video streaming services. Results show the approach of my implementation to be promising, encouraging future works, some of which are suggested at the end of this dissertation together with concluding remarks

System Architecture of a Mobile Message Transport System

Abstract-Many scenarios of beyond 3G mobile communications describe the integration of various access technologies into one system. Being always best connected under certain optimization criteria will be a crucial point for network operators and mobile users and requires network changes of mobile devices at runtime, the so-called vertical handovers. For those, bandwidth fluctuations up to the order of one or two magnitudes, e. g., when changing from an IEEE 802.11 to a GPRS System, have to be expected and applications have to cope with them in an user friendly way. Multi-modality and flexible data representations exploiting weights and semantic of transmitted data as means for making applications resource adaptive are currently under investigation. On top of that, device and system-wide adaptation control instances are needed to solve cross-layer and interapplication issues. This requires a rethinking of the classical communication paradigm of OSI-like protocol layering. With this paper, an overview on adaptation in communications is presented and an experimental framework providing system support for application adaptation and adaptation control is introduced as part of that discussion