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The trend of Next Generation Networks' (NGN) evolution is towards providing multiple and multimedia services to users through ubiquitous networks. The aim of IP Multimedia Subsystem (IMS) is to integrate mobile communication networks and computer networks. The IMS plays an important role in NGN services, which can be achieved by heterogeneous networks and different access technologies. IMS can be used to manage all service related issues such as Quality of Service (QoS), Charging, Access Control, User and Services Management. Nowadays, internet technology is changing with each passing day. New technologies yield new impact to IMS. In this paper, we perform a survey of IMS and discuss the different impacts of new technologies on IMS such as P2P, SCIM, Web Service and its security issues.

CDMA 방식은 미래의 모바일 네트워크를 위한 다중접속 방식으로 많은 주목을 받고 있으며 높은 무선 용량과 유연한 데이터 전송에 대한장점을 가지고 있다. 그리고 CDMA방식은 실시간 음성 및 비실시간 데이터 서비스를 제공하는 차세대 멀티미디어 시스템 분야에서 ITU에 제안된 주요 기술이다. 본 논문에서는 무선 채널에서 다중 접속 간섭 및 부분 대역 간섭의 제거와 시스템 채널 용량의 증가를 위해 MIMO-MC/CDMA 시스템의 용량을 평가하였다. 최근에 스펙트럼 효율과 링크의 신뢰도를 증가하기 위하여 다중경로를 이용하는 MIMO 방식이 제안되고 있다. 특히, 본 논문에서는 MIMO-MC/CDMA시스템의 채널 용량을 Eb/No, Mc, p, B에 따라서 평가하였다. 얻어진 결과로부터 채널용량을 개선하기 위해서는 신호의 요소들은 서로 무상관이어야하며 만약 부적당한 공간에 의한 상관과 부분 대역 간섭에 의한 주파수 간섭이 발생하만 MIMO-MC/CDMA 시스템의 채널 용량은 상당히 감소하게 됨을 알 수 있었다.

CDMA scheme has received a great deal of attenttion as a multiple-access method for future mobile networks. Its main advantage: are higher radio capacity and the capacity of flexible data tranmission. And CDMA scheme is a key technology in the proposals submitted to the ITU on next generation multimedia system with integrated services, namely real-time voice services and non real-time data services. In this paper, capacity evaluation of multiple-input multiple-output(MIMO) Multi-Carrier(MC)/CDMA system is considered to mitigate multiple access interference, partial-band interference and enhance system channel capacity in wireless channel. Recently, to increase the spectrum efficiency and the link reliability, MIMO-MC/CDMA scheme is devised to exploit multi-path in a scattering wireless channel. In particular, the channel capacity of MIMO-MC/CDMA system is evaluated according to Eb/No. Mc, p and B. From the results, in order to inappropriate spacing and the signals are frequency overlapped by partial band interference, the channel capacity of MIMO-MC/CDMA system becomes substantially smaller.

In this paper, we propose a new prioritized Optical Burst Switching (OBS) protocol based on a hop count, which can provide an efficient utilization in optical Wireless networks. Under several legacy schemes, a switch drops the burst with a shorter time among ones regardless of its traversed hop counts. As a result, the dropped burst that have been traversed more hops might cause to waste bandwidth than the one traversed a few hops. Noting that this problem, we propose the Just Enough Time (JET) with a hop count scheme which can reduce the wasted bandwidth by prioritizing the burst traversed more hops over others. From the simulation result, we show that the proposed scheme is advantageous over the legacy schemes in terms of the burst blocking probability and the link utilization.

The next generation mobile multimedia network is expected to provide higher-rate multimedia communication services to versatile mobile terminals moving in even higher speed. For achieving more efficient reusability of scarce radio resources and thereby accommodating more user population in this network, the smaller cell such as micro or pico cell structure is used. More efficient and faster hand-over schemes are necessary to prevent the degradation of QoS of multimedia services caused by hand-over processing delay and packet loss during frequent hand-over. This paper proposes a faster and more effective hand-over scheme for high-rate multimedia services in the future mobile multimedia networks. by utilizing the GPS information on the position of the mobile terminal and its estimated moving directions. The simulation results show that our proposed method provides a better performance than the conventional method.

Currently, the volume of multimedia contents and services being transmitted over the Internet is rapidly increasing. The surge in multimedia traffic load coupled with the increase of mobile multimedia devices especially in highly urbanized cities can greatly affect the quality of service and experience in multimedia services. In highly urbanized cities, mobile terminals tend to roam over heterogeneous wireless networks which are comprised of different radio access networks (RATs) where cooperation among them is necessary to provide seamless handovers for a robust multimedia service delivery. In addition, most wireless systems were deployed using centralized mode wherein significant issues in terms of latency, signaling overhead, packet loss were present. This paper deals with the integration of both host-based and network-based optimizations to provide seamless handovers to mobile multimedia devices as they roam across the heterogeneous wireless networks. It aims to propose a decentralized mobility handover scheme that integrates the advantages of both the features of Hierarchical Mobile IPv6 (HMIPv6) and Proxy Mobile Internet Protocol version 6 (PMIPv6), leveraging their advantages to reduce the handover latency of mobile multimedia devices, thus, providing a better quality of service and experience. The proposed scheme alleviates the performance of the standard MIPv6, HMIPv6, and PMIPv6 handover management protocols, addressing high latency, signaling overhead, higher packet loss rates, and most of the issues present in centralized systems.

Common information can be sent to multiple users with Broadcast/Multicast services. In smart home, multimedia services can be provided to users, who want to receive multimedia data through mobile phones. Most of multimedia applications are implemented using the streaming technique from contents provider to subscribers. It is important to manage the buffering amount remained in the user side in order to support the adequate quality of video contents and minimize complaints of subscribers due to buffer starvation. In the wireless environment, it is difficult to provide several subscribers with multicast traffic stably, since the data rate which users can receive varies according to the channel state of each user. Therefore, we propose and discuss an efficient usage together with MIU (Multicast In Unicast portion) as well as MIM (Multicast In Multicast portion) in order to maximize the aggregate throughput of users and minimize the starvation duration degrading QoS supported to users. We consider the multicast partitioning problem applying list partitioning algorithm and provide the analytical foundation that the proposed scheme can be evaluated. Simulation results show that proposed model can provide enhanced performance and allowed streaming quality.

Due to the characteristics of wireless mobile networks (e.g., node mobility, request fluctuation, poor quality of service), operators as well as service and content providers must cooperate to satisfy their customers. One of the solutions is the dynamic reconfiguration of service platforms, which is a real-time operation made on an initial configuration to improve the QoS parameters of the platform. Reconfiguration can be done by software means, and it can be material or logical, meaning that it may affect the physical or software components of the platform, the physical links, or also the transmitted information, without deteriorating the SLAs contracts signed between customers and operators. Several works have been already published in this direction but they fail in presenting a global view and a generic solution for the problem. This work is articulated in the form of a synthesis of the various solutions of reconfiguration which take place with coherence on the various levels of intervention. To this purpose, a model of a platform has been first developed; traffic and mobility models have been also injected to predict the movement and the demand pattern of the users. Moreover, several scenarios of reconfiguration were proposed for the change or the migration of software components, for the management network, the information routing, and the adaptation of the data. In a first part, we address the reconfiguration problem as a mono-objective optimization problem subjected to several constraints. We propose a mathematical model to deal with this situation. However, we found that finding rigorous solutions for this problem may have a huge computational cost. Hence, we also propose an alternative method introducing flow deviation and heuristics in the genetic algorithm. In the second part of our work, we deal with the behavioural aspect of the problem. It consists in considering the different metrics simultaneously and to seek a whole solution configuration representing various interesting compromises between the resources networks and the classes of services and users.

The purpose of this article is to design a multimedia streaming system with a complex structure as the one with a simple and basic work structure and realize system design that can enhance both expandability and portability based on that structure. To solve the problem that it is too complex and has low expandability, this study suggests a system design structure based on the LTS (Linear Task Set) model. Based on the simple, basic structure grounded on LTS structure, the study defines a consistent process and allows free structure alteration in the simple system structure according to the service purpose and demand. To secure independence and simplicity among components, the study defines a port channel object of a singleton structure and realizes design that can allow stream transmission and overall stream monitoring on the system for all ports with the port channel based on the mapping information of a component port. And based on this model, the paper suggests a component system model that can realize multimedia streaming service.

Nowadays, an increasing number of users get high-speed broadband access to the Internet. These broadband connections make new multimedia applications possible. However, such applications also introduce new Quality of Service (QoS) requirements to the network. Particularly, they require an assured bandwidth even in the case of network overload. The network itself has to provide such bandwidth assurances. This article introduces our concept of a novel network QoS device being located in network edge nodes. It provides a solution for relaxed QoS guarantees to certain flows on a congested link by focussing packet discard on selected flows. However, unlike for IntServ solutions like RSVP, our approach only requires minimal signalling and therefore provides both efficiency and scalability. We furthermore provide a quantitative performance evaluation of our QoS device by using simulations.

본 논문에서는 유비쿼터스 무선 센서 네트워크에서 전력 절약 고속 멀티미디어 서비스를 지원하기 위한 모델링 구조를 제안한다. 본 논문의 주요한 특징 및 기여도는 다음과 같다. 첫째, 물리계층에서 평균 전력을 유지하면서 전송 시간을 줄이는 방법 연구한다. 둘째, 스케일링 함수의 직교 조건을 사용하여 데이터 스트림을 전송하기 위해서 사용되는 데이터 전송 구간 시간을 줄인다. 이것은 제안된 임펄스 웨이브 형태가 정수배만큼 이동된 각각에 대해서 서로 직교하기 때문이다. 데이터 구간 시간은 데이터 동신에서 전송 시간과 직접적인 관계있으므로, 짧은 데이터 구간 시간은 전송 시간을 줄이고 라디오 네트워크의 용량을 줄인다. 마지막으로, 제안된 모델링 구조는 전력절약 고속 멀티미디어 서비스에 응용 적용 될 수 있다. 제안된 구조의 성능평가는 이론적인 분석을 통해서 이루어진다.

In this paper, we propose a modeling architecture to support power saving high-speed multimedia services in ubiquitous wireless sensor networks (UWSN). The main features and contributions of this paper are as follows. First, we focus on the reduction of transmission time while keeping average power in physical layer, which results in power savings. Second, using orthogonality condition of scaling function, we can reduce the data interval time which is used to transmit data stream since the proposed impulse waveform is orthogonal to its integer shifts each other. The corresponding data interval time relates to the transmission time in data communication. Shorter data interval time results in reducing the transmission time and increase the radio network capacity. Finally, the modeling architecture can be applied for power saving high-speed multimedia services in UWSN. The performance evaluation of the proposed architecture is achieved via analysis.

Enhanced Distributed Channel Access (EDCA) mechanism is used in WLAN to support QoS for various multimedia service flows. IEEE 802.11e EDCA introduces some new QoS parameters based on DCF. How to adjust these parameters is a significant problem. In the paper, we present a novel saturated throughput analysis of the IEEE 802.11e EDCA. This approach involves a novel analytical model that is an extension to previous works, which provide Markov chain analysis to IEEE 802.11e EDCA. Throughput analysis of our model is evaluated by comparison with NS2 simulations. We found the model is correct and suitable for both basic access and request-to-send/clear-to-send (RTS/CTS) access mechanisms.

본 논문은 모바일 ad-hoc 무선 센서 네트워크에서 전력 절약 고속의 멀티미디어 서비스를 지원하는 Cross-Layer 전송 구조(CLTA)를 제안한다. 본 논문의 주요한 목적은 모바일 ad-hoc 무선 센서 네트워크에서 경로들의 생존시간(lifetime)을 증가시키기 위해서 노드들의 이동성 기반위에서 경로의 안정성을 결정하는 방법과 전송전력을 절약하는 방법을 제안하고 보여주는 것이다. 이러한 목적을 달성하기 위해서 본 연구에서는 네트워크 계층 기술과 물리계층 기술의 융합과 상호 유기적인 관계로 인해서 시너지 효과를 얻을 수 있는 Cross-Layer 구조 전략을 제안한다. 기존의 연구들은 주로 고정된 노드들로 구성된 센서 필드 환경에서 연구가 진행된 반면에, 본 논문은 센서 필드에서 고정된 노드들뿐만 아니라 이동 센서노드들도 함께 고려한 좀 더 실제적인 환경에서 연구가 진행된다. 제안된 구조(CLTA)의 성능평가는 시뮬레이션과 이론적인 분석을 통하여 이루어진다.

In this paper, we propose a Cross-Layer Transmission Architecture (CLTA) to support power saving high-speed multimedia services in mobile ad-hoc wireless sensor networks(MAWSN). The main goals of this paper are in showing and proposing how the routing routes are decided on route stability based on mobility of mobile nodes to increase the operational lifetime of routes as well as how the transmit power can be saved in mobile ad-hoc wireless sensor networks. To obtain these goals, we propose a cross-layer architecture strategy which combines network layer technology with physical layer technology to get synergy effects in the view of transmission power saving. We consider a realistic approach, in the points of view of the MAWSN, based on mobile sensor nodes as well as fixed sensor nodes in sensor fields while the conventional research for sensor networks focus on mainly fixed sensor nodes. The performance evaluation of the proposed CLTA is performed via simulation and analysis.

In the process of a mobile network evolution to the All-IP, it is inevitable to experience a transient period embracing both circuit and packet based data traffics. At the stage of those hybrid networks, it is important to build them in an efficient manner in terms of resource utilization which is closely related to the overall system operation cost. Especially, the multimedia telephony is one of the essential services in the advanced packet based mobile networks. In this paper an effective method of system operation is proposed for building up the multimedia telephony service while the legacy network co-exists. The proposed solution is based on the careful investigation of the usage pattern of the multimedia services in the evolving networks. This method is also expected to be a useful guideline for the network resource planning.

Mobile IPv6 has been developed to enable mobility in IP networks for mobile terminals. Mobile IPv6 security standardization is still ongoingand security issues are one of the primary considerations that need to be address. In this paper we proposed a mechanism that if will be adopted;MIPv6 will have a better security. This proposed new security mechanism for Mobile IPv6 which to make the RR method more secure is to use IPSec ESP in tunnel mode between the MN and the HA when sending the messages 1(MN to the CN) and 3 (CoA to the CN) and CGA method should be used in parallel with the RR to provide better security. If these messages are also encrypted in addition to authentication, anyone in the foreign network of the MN cannot break the security of the protocol.

The emergence of cloud computing brought a significant change for the delivery of how Information Technology to educational and business enterprises. In this paper, we discuss the different qualities of cloud computing frameworks together with the expectations and promises of cloud computing and associated benefits. The design of a cloud computing framework is presented and its components to realize the identified qualities. A successful cloud solution delivers the qualities of being flexible and has the ability to easily work with multiple programming and platform or run-time environments.

A hierarchical system of wireless USB (WUSB) over wireless body area networks (WBAN) is adopted for wearable health-monitoring systems (WHMS). It is executed on the basis of WUSB over WBAN protocol at each wearable sensor node comprising the WHMS. Basically, a single WHMS operates based on WUSB over WBAN protocol. And the multiple WHMSs operate based on the WiMedia D-MAC protocol and dual-role device (DRD) function. In this paper, a multimedia streaming scheme for N-screen services is proposed for WHMS networks. In a hospital, N-screen applications must be required by using WHMS networks. The multimedia streaming scheme for N-screen services is composed of service interval-based resource allocation and multicast reservation schemes. In simulation results, efficiency of the multimedia streaming scheme is proven through throughput and delay performances at an N-screen service scenario.

Ethernet passive optical networks (PONs) are an emerging access network technology that provides a low-cost method of deploying optical access lines between a carrier's central office and a customer site. In this paper, we propose a new algorithm of dynamic bandwidth allocation for multimedia services over Ethernet PONs. To implement the suggested dynamic bandwidth allocation algorithm, we present control message formats that handle classified bandwidths in a multi-point control protocol of Ethernet PONs.