Editorial (001-002)
        Qun Jin and Tomoya Enokido

Research Articles

MPLS Traffic Engineering for Multimedia on Satellite Networks (003-011)  
        Arjan Durresi, Mimoza Durresi, Leonard Barolli, and Fatos Xhafa 
Broadband satellite constellation networks will be required to carry all types of IP traffic, real time interactive traffic as well as non-real time one, warranting the need for appropriate QoS for these different traffic flows. In this paper we investigate the need for MPLS traffic engineering in GEO/MEO/LEO satellite networks to address QoS issues. We compare the service received by TCP and UDP flows when they share a link and when they are routed on explicit MPLS traffic trunks. Since MPLS traffic trunks allow non-shortest path links also to be used, the total network throughput goes up with proper traffic engineering. If UDP and TCP flows are mixed in a trunk, TCP flows receive reduced service as the UDP flows increase their rates. Also, we found that with MPLS traffic engineering we can protect real time traffic and VoIP traffic from packet loss and excessive jitter by separating them from other congestion unresponsive flows.

Narrowcasting for Articulated Privacy and Attention in SIP Audio Conferencing (012-028)  
        Sabbir Alam, Michael Cohen, Julian Villegas, and Ashir Ahmed 
In traditional conferencing systems, participants have little or no privacy, as their voices are by default shared with all others in a session. Such systems cannot offer participants the options of muting and deafening other members. The concept of narrowcasting can be applied to make these kinds of filters available in multimedia conferencing systems. Our system treats media sinks (in the simplest case, listeners) as full citizens, peers of the media sources (conversants' voices), and we defined therefore duals of {\tt mute} \& {\tt select}: {\tt deafen} \& {\tt attend}, which respectively block a sink or focus on it to the exclusion of others. In this article, we describe our prototyped application, which uses existing standard Session Initiation Protocol (SIP) methods to control fine-grained narrowcasting sessions. The runtime system considers the policy configured by the participants and provides a policy evaluation algorithm for media mixing and delivery. We have integrated a ``virtual reality''-style interface with this SIP backend to display and control articulated narrowcasting with figurative avatars.

Mobile Music Therapy with Multimedia Quality of Life Supporters for Elderly and Disabled (029-044)  
        Nikolay Mirenkov, Kamen Kanev, and Hiroshi Takezawa 
Music Therapy (MT) addresses physiological, cognitive, and social needs of individuals and employs music to enhance quality of human lives through creation of positive changes. In this paper, we consider applying mobile MT to human-computer interfaces, based on Quality of Life Supporters (QLS) of self-explanatory type, and oriented to elderly and disabled people. QLS are multi-modal communicators for person-environment (P-E) fit adjustments that take into account individual emotions and well-being. The "Circumplex model" published by Russell (1980) is employed for constructing optimal sequences of steps allowing smooth transition between any current and target emotional states in the course of computer assisted sessions. Findings regarding optimal step sizes and preferable types of music applicable for each step, as well as empirical methods of acquiring knowledge concerning relations between music and emotions are reported in result.

Data Transmission Procedures for a Multi-Source Streaming Model in Mobile Peer-to-Peer (P2P) Overlay Networks (045-063)  
        Alireza G. Nemati and Makoto Takizawa 
In peer-to-peer (P2P) overlay networks, multimedia contents are in nature distributed to peers by downloading and caching. Here, a peer which transmits a multimedia content and a peer which receives the multimedia content are referred to as source and receiver peers, respectively. A peer is realized in a process of a computer and there are mobile and fixed types of computers. A peer on a mobile computer moves in the network. Furthermore, a peer maybe realized as a mobile agent. Thus, not only receiver peers but also source peers might move in the network. In this paper, we would like to discuss how source peers deliver multimedia contents to receiver peers in a streaming model so that enough quality of service (QoS) required is supported in change of QoS of network and peer, possibly according to the movements of the peers. In this paper, we discuss a multi-source streaming (MSS) protocol where a receiver peer can receive packets of a multimedia content from multiple source peers which can support enough QoS. If a current source peer is expected to support lower QoS than required, another source peer takes over the source peer and starts sending packets of the multimedia content. The receiver peer is required to receive packets of the multimedia content with enough QoS, e.g. no packet loss even if the source peer is being switched with a new source peer. We discuss how to switch source peers so as to support enough QoS to the moving receiver peer. We evaluate the MSS protocol in terms of the fault ratio, i.e. how frequently the receiver peer fails to receive packets with enough QoS and show the MSS protocol can reduce the fault ratio.

Deterministic Trust Management in Pervasive Computing (064-080)  
        Mieso K. Denko, Tao Sun, and Isaac Woungang
An effective trust management technique plays a vital role in evaluating relationships among devices in pervasive computing. In this paper, we propose a deterministic trust management scheme that aims at establishing trust relationships among devices using direct and indirect computation methods. Recommendations and trust updating mechanisms are used to increase the reliability of trust computations. We have carried out performance evaluations using simulation experiments. The results show that trust management with recommendation outperforms other schemes.

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