the success of Wi-Fi and emergence of Wi-MAX creates exciting technology and business challenges for the communication industry. Roaming, seamless voice and data hand-offs, in conjunction with continuity of voice serv...
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ISBN:
(纸本)0780394283
the success of Wi-Fi and emergence of Wi-MAX creates exciting technology and business challenges for the communication industry. Roaming, seamless voice and data hand-offs, in conjunction with continuity of voice services such as Messaging, Push-to-talk, and Voicemail, are posing the next technology and business challenges. Services convergence among Wi-Fi, Wi-MAX, and Cellular networks is creating opportunities for both wireless, and wireline service providers. Similar opportunity exists for enterprises for the first time. Services convergence can give enterprises the freedom similar to "PBX"es for wireless access on and off campuses. As the business cases for enterprises and wireline service providers are pitted against each other on the commercial front, the technologies will evolve out of market leverage, presence and acceptance. this poses a challenge for technologists to create a technology that is easily deployable in target scenarios. the requirements exist for a solution that, independently of the end user and service providing entity, can fulfill the "service quality" expectations of users and providers. In this talk, we discuss the requirements of voice service convergence solutions, protocols, standardization effort, and challenges for solution development. We also allude to the opportunities for research and development of newer technologies. these innovations will breach the current gaps in convergence of services beyond packet to circuit call control mechanisms and extend them across different access technologies, such as Wi-Fi, Wi-MAX, GSM, CDMA, and others.
Based on the analysis of FEC/ARQ transmission mechanism, we propose a novel transmission mechanism of AFEC (Adaptive Forward Error Correction) code in this paper in order to improve the jitter performance on the clien...
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ISBN:
(纸本)0780394283
Based on the analysis of FEC/ARQ transmission mechanism, we propose a novel transmission mechanism of AFEC (Adaptive Forward Error Correction) code in this paper in order to improve the jitter performance on the client end. the new mechanism modifies the method of information exchanging between the server end and client end. In the FEC/ARQ mechanism, the server end does not transmit data until it receives the feedback message about the acceptance status of the previously transmitted data, which badly affects the jitter performance on the client end the new mechanism adopts 2-level AFEC code, which allows the server to adjust the FEC redundancy and sending rate in accordance withthe control messages feed back by the client. And even in the case of the lack of the feedback message, the server using the new mechanism does not slop sending data. Based on the Network Simulator 2 platform, we simulate FEC/ARQ and AFEC respectively. And both mechanisms are experimented on the same working condition and they are tested for 3 different conditions. the comparison between the NS2 simulation results of these two schemes proves that the newly proposed AFEC transmission mechanism can improve the jitter performance on the client end.
Peer-to-Peer computing is mainly based on the virtual overlay network constructed in the application layer. Often, there is topology mismatching between the overlay network and the physical network, which may cause gr...
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ISBN:
(纸本)076952513X
Peer-to-Peer computing is mainly based on the virtual overlay network constructed in the application layer. Often, there is topology mismatching between the overlay network and the physical network, which may cause great traffic overhead In this paper, we study the topology mismatching problem and its impact on communication in wireless ad hoc networks. We present an efficient, fully distributed algorithm, named D-TAOC, for constructing the overlay network. By qualitative analysis and simulation experiments, we show that D-TAOC can significantly reduce the traffic overhead while slightly sacrificing the routing efficiency. We also prove that D-TAOC works well in a dynamic peer-to-peer environment.
the management of unpaved mine road networks varies widely, from small low-tonnage operations where adhoc techniques are applied, to extensive networks of roads subject to large numbers of high axle loadings, where ha...
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the management of unpaved mine road networks varies widely, from small low-tonnage operations where adhoc techniques are applied, to extensive networks of roads subject to large numbers of high axle loadings, where haul road maintenance management systems (MMS) have been successfully implemented. In a dynamic mining environment - typically mines in which production is managed by a centralised truck dispatch system, truck diagnostic and allocation data is relayed within a broader asset management and centralized communication and GPS backbone. this enables road condition to also be monitored on a real-time basis and the data integrated within the centralized truck management system to form a road maintenance management system - the condition triggered maintenance - or CTM system. this paper presents the background to CTM system development. Following an introduction to the system architecture, the results of system trials are briefly discussed in the light of analytical and modelling issues, road defect signature recognition and system limitations. the paper concludes that truck on-board multi-sensor data integration withthe existing mine communication and asset management systems can provide the basis for a real-time mine road maintenance management system, with resultant improvement in service and reduction in total road-user costs.
In a multimedia service such as Video-On-Demand system, video streaming requires allocation of several communication channels. the overall cost of establishing a Video-On-Demand system also includes the channel cost. ...
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Summary form only given. On-board computer, in-car video and wireless network connection are increasingly becoming standard equipment in police vehicles nowadays. As mobile phone service providers expand aggressively ...
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Summary form only given. On-board computer, in-car video and wireless network connection are increasingly becoming standard equipment in police vehicles nowadays. As mobile phone service providers expand aggressively their broadband data access, more and more law enforcement agencies are tapping into this resource for sharing of multimedia data in an effort to improve efficiency and interoperability. In this talk, I will present applications in which wireless communication plays an important role in making law enforcement more effective and safer for police officers. Examples include real-time database query, remote surveillance, multimedia streaming and wireless monitoring of high-risk targets, among others.
In a multimedia service such as video-on-demand system, video streaming requires allocation of several communication channels. the overall cost of establishing a video-on-demand system also includes the channel cost. ...
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In a multimedia service such as video-on-demand system, video streaming requires allocation of several communication channels. the overall cost of establishing a video-on-demand system also includes the channel cost. Several caching and batching schemes have been proposed in literature for the optimal utilization of these channels. A viewer is served with a mix of main and small (e.g. advertisement) movies. the requested movies not necessarily will be of same duration. this study deals withthe system having limited number of channels and servicing of requests for mixed movies of different durations. the system is modeled for its behavior with a continuous time Markov chain (CTMC) process. the performance measures such as channel utilization, number of channels in use, blocking probability of channels, cost and duration after which the proposed system starts yielding profit etc. are quantified in terms of various design parameters like, total number of channels, users request arrival rate, and batching interval, request service rate etc.
Summary form only given. this paper identifies trends in the American mobile data services market and presents forecasts for prevailing prices both retail and wholesale - in the 2015 timeframe. For purposes of this st...
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Summary form only given. this paper identifies trends in the American mobile data services market and presents forecasts for prevailing prices both retail and wholesale - in the 2015 timeframe. For purposes of this study, mobile data services consist of messaging and switched data services (including Internet access) offered over cellular/personal communications service networks. the paper is organized as follows. Initially, we provide information on the mobile data market as it exists today and how it is expected to develop over the next few years. then we describe the supply side; that is, how telecommunications companies are planning to provide mobile data services and the expected pricing trends. In addition, we address the demand side - the expected consumer demand for mobile data services and projections on consumer willingness to pay. Finally, we provide conclusions and forecasts resulting from the analysis.
Summary form only given. Dense wavelength division multiplexing (DWDM) transmission systems have been used in commercial networks to transport massive data over long distances. the majority of the backbone DWDM system...
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Summary form only given. Dense wavelength division multiplexing (DWDM) transmission systems have been used in commercial networks to transport massive data over long distances. the majority of the backbone DWDM systemsthat are deployed today are point-to-point with limited reach and capacity. To reduce the transport cost per bit and operating cost, new technologies have been developed to transport more bits per second over longer distances with intelligent network flexibility and performance monitoring features. this talk will provide an overview of evolution from today's point-to-point transport networks to next generation reconfigurable high-capacity and ultra long-haul mesh transport networks. Key elements and enabling technologies to build next generation mesh networks will also be reviewed.
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