Khaled Mahmud

Energy Consumption Measurement of Wireless Interfaces in Multi-Service User Terminals for Heterogeneous Wireless Networks

For future generation mobile networks, we expect that the mobile devices like PDAs, note PCs or any VoIP-enabled communicators will have the feature of being always switched on, ready for service, constantly reachable by the wireless Internet. In addition to high access speed, attractive real-time contents or other expected spectacular features of the future wireless Internet environment, the mobile terminals has to be very much energy-aware to enable literal untethered movement of the user. Mechanisms for network activities like maintaining location information and wireless system discovery, which require regular network access, should be energy-efficient and resource-efficient in general. Cellular systems employ the notion of passive connectivity to reduce the power consumption of idle mobile hosts. In IP based Multi-service User Terminal (MUT) that may have multiple wireless interfaces for receiving various classes of services from the network, there should be an efficient addressing of the energy consumption issue. To devise an energy-efficient scheme for simultaneous or single operation of the wireless interfaces attached to such terminals we should have comprehensive understanding of the power consumption of the devices/modules in various operational states. This paper investigates the power consumption pattern or behavior of some selected wireless interfaces that are good candidates for being part of the future of the multi-service user terminals. We propose a simple model for predicting energy consumption in a terminal attributed to the wireless network interfaces. We measured the actual consumption pattern to estimate the parameters of the model.

Measurement and usage of power consumption parameters of wireless interfaces in energy-aware multi-service mobile terminals

For IP-based always-on type multi-service user terminals, which may have multiple wireless interfaces, energy-efficiency is a key requirement. It is crucial to take into account the power consumption behavior and delay patterns associated with each state and transitions of the wireless devices to formulate efficient operation of multi-module terminals, especially in services where media/session handover between wireless networks are targeted. This paper investigates the power consumption pattern or behavior of some selected wireless interfaces that are good candidates for being part of the future of the multi-service user terminals. We propose a simple model for predicting energy consumption in a terminal attributed to the wireless network interfaces. We measured the actual consumption pattern to estimate the parameters of the model.

Context-Based Network and Application Management on Seamless Networking Platform

A context-based adaptive communication system is introduced for use in heterogeneous networks. Context includes the users presence, location, available network interfaces, network availability, network priority, communication status, terminal features, and installed applications. An experimental system was developed to clarify the feasibility of using context information to flexibly control networks and applications. The system operates on a seamless networking platform we developed for heterogeneous networks. By using contexts, the system can inform the caller and callee of applications they can access, which are available through the network before communication occurs. Changes in contexts can switch an on-going application to another during actual communication. These functions provide unprecedented styles of communication. A business scenario for a seamless networking provider is also presented.

Basic access network assisted IP mobility and AAA in MIRAI architecture

A novel architecture for future integrated wireless network is proposed in MIRAI (Multimedia Integrated network by Radio Access Innovation) where a dedicated network takes care of the mobility functionalities of the participant wireless networks in the integration. The dedicated network, called basic access network (BAN) is used for paging whenever a call arrives for the mobile user for any of the wireless interfaces of the users multiservice terminal. We analyze a scheme for using the BAN channel, and associated network to aid the AAA (authentication, authorization and accounting) and IP mobility functionalities of the integrated network environment in a seamless fashion.

Prototype of context-based adaptive communication system on seamless networking platform

A context-based adaptive communication system is introduced for use in heterogeneous networks. The context includes the users presence, location, available network interfaces, network availability, network priority, communication status, terminal features, and installed applications. An experimental system was developed to clarify the feasibility of using context information to flexibly control a network and applications. The system operates on a seamless networking platform we developed for heterogeneous networks. By using contexts, the system can show the caller and its callee the applications they can access that are available through the network before communication occurs. Changes of the contexts can switch the on-going application to another during communication. These features provide us with unprecedented styles of communications.

Mobility management by basic access network in MIRAI architecture for heterogeneous wireless systems

A novel architecture for future integrated wireless network is proposed in MIRAI (Multimedia Integrated network by Radio Access Innovation) where a dedicated network takes care of the mobility functionalities of the participant wireless networks in the integration. The dedicated network, called Basic Access Network (BAN) is used primarily for wireless system discovery and paging whenever a call is initiated or a call arrives for the mobile user for any of the wireless interfaces of the users multi-module, multi-service terminal. In this paper, we analyze a model for using the BAN channel, and associated network to perform mobility functionalities of the integrated network environment in a seamless fashion.

Design and implementation of out-of-band signaling for seamless handover in wireless overlay networks

An out-of-band basic access signaling (BAS) protocol is introduced for use in heterogeneous wireless networks. The BAS protocol enables a mobile terminal to communicate with an agent in a fixed network through any radio access network (RAN) chosen by the user as the basic access network (BAN). The agent uses the information on the location of mobile terminals and on the availability of RANs to decide which RAN to use, taking the users preferences into account. This protocol was implemented in a demonstration system using existing radio systems and the standard mobile IP protocol. The separation of the signaling path from the data paths was found to save energy and to facilitate handover between RANs.

A novel mobility management framework for future generation integrated wireless networks

The concept of using a separate network to carry signaling packets related to some basic mobility management functions in a heterogeneous wireless network environment has been proposed in MIRAI (multimedia integrated network by radio access innovation) architecture (see Wu, G. et al., IEEE Commun. Mag., p.126-34, 2002). In MIRAI architecture, a dedicated network takes care of the mobility functionalities of the participant wireless access networks. The dedicated network, called basic access network (BAN), is primarily used for paging whenever a call arrives for the mobile user for any of the wireless interfaces of the users multi-service terminal, and for wireless system discovery when the user wants to initiate a call/session. We present the operation of the BAN in concert with the rest of the IP-based network, to realize a common signaling framework for heterogeneous mobility.

Basic access network - the signaling-only network for power-efficient mobile multiservice terminals in MIRAI architecture

In MIRAI (Multimedia Integrated network by Radio Access Innovation) architecture, proposed by Wu, Havinga and Mizuno (see IEEE Commun. Mag., p.126-134, Feb. 2002), a dedicated network takes care of the mobility functionalities of the participant wireless access networks in an integrated wireless networks environment. This paper presents the dedicated network, called basic access network (BAN), which is primarily used for paging whenever a call arrives for the mobile user for any of the wireless interfaces of the users multiservice terminal, and for wireless system discovery when the user wants to initiate a call/session. The resultant improvement in network signaling and terminal power usage efficiency is discussed. The paper also outlines the implementation issues of the air interface of this unique network, with specific focus on the system capacity, coverage and power usage.

Variable Rate Transmission for Higher System Capacity in a Signaling-Only Wireless System

System capacity of a wireless system can be improved greatly by using variable rate transmission. Assuming a low-rate and wide-coverage signaling-only wireless network, in this paper we evaluate, analytically and numerically, the extent of this improvement for various schemes with variable transmission rates. We considered log-normal shadowing as well as the effect of Rayleigh fading. Simulation results show close proximity with the analytical predictions.