Jukka Manner

Energy Consumption Analysis of WLAN, 2G and 3G interfaces

Mobile devices people carry in their pockets every day can use various means to connect to data services all around the Internet, e.g., 2G, 3G and WLAN. This has been an important development towards an easily accessible and always-on the Internet. While radio connectivity, bits rates in particular, has developed tremendously during the recent years, battery technology and electronics has not. Thus, the more we use Internet services on mobile phones, the faster the battery of the device runs out, even within a few hours. This paper analysis various radio technologies found in modern mobile phones, and characterize their power consumption with different uplink and downlink data transfers. We are interested to understand how much energy is needed per bit of user data when sending or receiving data over various wireless links.

Evaluation of mobility and quality of service interaction

With the fast adoption of IP-based communications for mobile computing, users are expecting a similar service in wireless and wired networks. This raises the need for setting guarantees to the quality of the offered service (QoS), despite the technology of the access network (AN) or the mobility of the terminal. As mobile computing is getting more popular on a daily basis, new broadband cellular wireless ANs will appear with overlapping coverage in hot spots. This generates a new challenge for QoS provision, as it will have to deal with fast mobility of terminals. Various QoS architectures have been defined, but none provides full support for guaranteed service levels for mobile hosts (MHs). This paper discusses the problems related to providing QoS to MHs and identifies the existing solutions and future work needed.

Achieving seamless mobility in IP-based radio access networks

A handover in any IP-based mobile network is a complex procedure. Typically, it takes quite a long time before the new access router gets the parameters describing the flow states associated with an incoming mobile node. It may even be that the new access router does not have enough resources to support the rerouted flows. Thus, it is crucial to select from several candidate access routers the one that best fits the mobile nodes requirements. This article describes the candidate access router discovery protocol, which can be used to select a suitable new access router. We also address the context transfer architecture that makes use of the candidate access router discovery protocol and aims to reduce the time required to recover flow descriptor parameters. Finally, we discuss how the two protocols can intemperate to achieve seamless handovers.

The BRAIN quality of service architecture for adaptable services with mobility support

Next generation IP networks and applications will have to address the increasingly important challenges of wireless access, mobility management, the provision of quality of service (QoS), and multimedia issues. These problems form the basis of the research within the EU financed BRAIN (Broadband Radio Access for IP based Networks) project. The project is developing a novel architecture that will be able to deal with the extreme QoS violations that are likely to occur during a running session that is exposed to the radio access environment. The core of this architecture supports different types of applications. It inherits and develops from the traditional Internet approach, but incorporates aspects of a modern flexible QoS middleware solution. The given problem is addressed in a comprehensive, modular, and open manner, by providing different APIs to different types of applications. It provides powerful functions to application programmers, but does not assume that lower level functionality must be hidden from the application programmer. It encompasses a variety of objects, APIs, end-system mechanisms and protocols to cope with the dynamic variation in mobility management and QoS. This solution will provide applications with more predictable services and allow applications to react in a pre-determined way to QoS violations.

Mobile network measurements - It's not all about signal strength

Platforms for measuring cellular networks from mobile phones are very popular. Unfortunately, they all suffer from a simplistic approach and measurement errors, and questions how to interpret these measurements. One such error source is that it is easy to measure the signal strength but hard to draw exact conclusions from it. Our work focuses on understanding the measured signal strength and analyzing its relationship to enduser service quality. To study interesting causalities, such as the above, between different parameters we developed a measurement platform called Netradar for gathering information from mobile devices. We show the correlation between signal strength and TCP goodput in graphs and geographical maps, and the behavior depending on time of the day. We also discuss grouping of measurements to enable estimating the quality of connectivity in an area.

A Survey of Ethernet LAN Security

Ethernet is the survivor of the LAN wars. It is hard to find an IP packet that has not passed over an Ethernet segment. One important reason for this is Ethernets simplicity and ease of configuration. However, Ethernet has always been known to be an insecure technology. Recent successful malware attacks and the move towards cloud computing in data centers demand that attention be paid to the security aspects of Ethernet. In this paper, we present known Ethernet related threats and discuss existing solutions from business, hacker, and academic communities. Major issues, like insecurities related to Address Resolution Protocol and to self-configurability, are discussed. The solutions fall roughly into three categories: accepting Ethernets insecurity and circling it with firewalls; creating a logical separation between the switches and end hosts; and centralized cryptography based schemes. However, none of the above provides the perfect combination of simplicity and security befitting Ethernet.

Comparison of load-balancing approaches for multipath connectivity

During past years, the so-called resource pooling principle in data networks has been studied more carefully. For example, the recent work on routing on the Internet over multiple paths and Multipath TCP both seek to make the best possible use of multiple connecting paths between two end points. In deployments where multiple users could share multiple paths, one of the very first questions that comes to mind is, should we schedule packets from the users on a per-flow or per-packet basis? In this paper we study networking scenarios in which several networks are connected to each other via multiple paths. We seek to understand how a multi-homed router should schedule packets and packet flows out towards other networks. Our primary interests are to study path utilization and analyze the bandwidth fairness of various approaches using different traffic loads.

Evaluation of data compression for energy-aware communication in mobile networks

The development of ICT following Moores Law has resulted in a situation where mobile users are able to make use of a wealth of versatile services. Yet, battery and electronics technology has not followed this development as well, which has resulted in a situation where a mobile users battery can only enable a few hours of active use. Therefore, we need to focus increasingly on energy efficient wireless and mobile communication to reduce energy consumption, but also to cut down greenhouse emissions and improve business competitiveness. Due to significant energy consumption of transmitting data over wireless networks, data compression techniques are one simple way to trade the overhead of compression for less communication energy. This paper investigates the usages of data compression to reduce the energy consumption in a modern hand-held device. By conducting various experiments, we analyze content-aware compression schemes that can reduce energy consumption significantly. Yet, blind or careless use of compression results in a huge energy loss. We also discuss the deployment issues of data compression.

SDN optimized caching in LTE mobile networks

This paper provides an overview of the current LTE architecture and the proposed solutions to integrate Software Defined Network (SDN) technology. The integration of SDN into mobile networks become Software Defined Mobile Network (SDMN), which provides new benefits such as dynamic and efficient caching. Firstly, the paper proposes the integration of SDN in LTE networks on disruptive approach that replaces current mobile transport with SDN based network. Secondly, the benefits of SDN integration to provide optimized content caching is presented. This paper presents a concrete advantage of SDMN for content delivery. Thus, the paper describes the benefits from operator and end user points of view based on a simple scenario of content delivery using dynamic caching reallocation.

A layer-2 approach for mobility and transport in the mobile backhaul

GTP tunnels are used to transport user data packets in LTE networks over the mobile backhaul between the base stations and core network elements. Maintaining the tunnel as the user equipment moves requires heavy signaling. Moreover, the protocol stack effectively adds headers and thus introduces overhead. In this paper, we design and analyze an LTE architecture and mobility management solution that is based on layer-2 switching. We remove the GTP tunnel and its associated IP/UDP tunnel, and embed user IP packets directly in Ethernet frames within the mobile backhaul. Mobility management within an access network is distributed. We show that the design is very efficient and would simplify the future LTE evolution.