Notification:
We are currently experiencing intermittent issues impacting performance. We apologize for the inconvenience.
By Topic

Broadband Network & Multimedia Technology, 2009. IC-BNMT '09. 2nd IEEE International Conference on

Date 18-20 Oct. 2009

Filter Results

Displaying Results 1 - 25 of 189
  • [Front cover]

    Publication Year: 2009 , Page(s): c1
    Save to Project icon | Request Permissions | PDF file iconPDF (130 KB)  
    Freely Available from IEEE
  • [Title page]

    Publication Year: 2009 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | PDF file iconPDF (96 KB)  
    Freely Available from IEEE
  • Contents

    Publication Year: 2009 , Page(s): 1 - 16
    Save to Project icon | Request Permissions | PDF file iconPDF (75 KB)  
    Freely Available from IEEE
  • Unidirectional link problem in AODV routing protocol

    Publication Year: 2009 , Page(s): 1 - 4
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (76 KB) |  | HTML iconHTML  

    Ad hoc is a kind of self organized network which is different from traditional communication system. In recent years, ad hoc network has been well developed. AODV (ad hoc on-demand distance vector) is an important protocol of ad hoc network which is recommended by IETF by its simple operation and outstanding performance. However, AODV protocol is not perfect so far, which still has some issues needed to be amended. In this contribution, a unidirectional link problem in AODV protocol is discussed and several effective solutions are proposed, and some theoretical analysis is referred for performance comparison. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A scheme based on mobility for on-demand route protocol in ad hoc networks

    Publication Year: 2009 , Page(s): 5 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (160 KB) |  | HTML iconHTML  

    Broadcasting, which usually incurs serious problems by flooding, is a common operation in MANET (mobile Ad hoc networks), especially in on-demand route protocol. In order to relieve such limitations, in this paper, we propose an improvement over the former blind flooding approach by using a scheme based on the mobility of nodes (MON). In MON scheme, we categorize mobile hosts into active nodes and inactive nodes according to their relative high or low mobility. Inactive nodes forward packets for other nodes while active nodes do not. In simulation, we approve the advantages of our approach in most cases by comparing it with AODV in terms of several metrics. Finally, the advantages and disadvantages of MON are concretely analyzed in theory. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • EPI-T: A novel routing protocol for intermittently connected networks

    Publication Year: 2009 , Page(s): 10 - 14
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (89 KB) |  | HTML iconHTML  

    In intermittently connected networks, epidemic routing protocols have been widely used as its simplicity and reliability. However, this kind of protocols will make the same message cover most of the nodes in networks which causes a huge waste of network resources. Therefore, this paper proposes a new routing protocol named epidemic routing based on separation time with forwarding tokens constrained (EPI-T). EPI-T selects a route according to the idea of epidemic routing and history information, which can restrict flooding range and saves the network resources. Simulation results show that EPI-T improves delivery ratio and shortens the message delivery delay. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Priority based bandwidth allocation scheme for WIMAX systems

    Publication Year: 2009 , Page(s): 15 - 18
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (111 KB) |  | HTML iconHTML  

    IEEE 802.16 based wireless access scheme (commonly known as WiMAX) is considered as one of the most promising wireless broadband access schemes for communication networks in metropolitan areas today. One of the most challenging tasks in the access scheme is the need to support quality of service (QoS). The paper proposes a priority based bandwidth allocation mechanism in WiMAX networks which is compliant with the standards. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On parameter settings of network keep-alive protocol for failure detection

    Publication Year: 2009 , Page(s): 19 - 23
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (81 KB) |  | HTML iconHTML  

    The keep-alive protocol (or Hello protocol) relying on exchanging periodical keep-alive or Hello messages is often used by many network protocols to detect link, node or other network-related failures. The effectiveness of the Hello protocol depends on the proper setting of its two parameters. Most existing work on the study of the parameter settings was related to a specific environment in connection with a specific network protocol. Independently of any given associated network protocol, this paper studies the impact of network overload, especially the message loss probability, on the choice of these two parameters through both analysis and simulations. The studies show that in lightly-loaded networks with small message transmission loss probability both parameters of the Hello protocol can be set to small values and we can get a fast failure detection time and small number of false alarms. However, in heavily-loaded networks with large message transmission loss probability, the Hello protocol is not effective at all for any parameter values. In normal situations, adaptive changes of the parameters of the Hello protocol are useful. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Research and simulation of distributed QOS routing algorithm

    Publication Year: 2009 , Page(s): 24 - 27
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (100 KB) |  | HTML iconHTML  

    Base on the QOS requirements of modern broadband networking, the paper presents our recent research on QOSPF in the on-demand computing over the traditional OSPF. The disadvantage in a distributed routing protocol under the QOS requirement is firstly discussed; then a new QOSPF which supports the QOS routing scheme is proposed. The advantage of new approach is demonstrated in the simulation of OSPF and QOSPF through the NS-2. Limitation of the method and future research for improvement are also discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A token cycle scheduling of MAC protocols for TDMA based airborne ad hoc network

    Publication Year: 2009 , Page(s): 28 - 32
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (90 KB) |  | HTML iconHTML  

    The MAC problem in a wireless network has intrigued researchers for years. The MAC protocol is also important for airborne ad hoc network in order to reducing TDMA overhead, increasing TDMA throughput, and decreasing End-to-End delay. Our proposed Token Cycle Scheduling described in this paper allow the exchange of control information in an efficient and contention free manner such that each participating node can, in real time, converge to a consistent TDMA schedule. The dynamic resource needs of participating nodes can be rapidly accommodated for QoS guarantees. The scheduling algorithms are topology independent and require the nodes states to assignment right slot to each node in order to dynamically adapt to changing wireless network topologies. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of transmission capacity of wireless ad hoc networks with power control

    Publication Year: 2009 , Page(s): 33 - 37
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (93 KB) |  | HTML iconHTML  

    An ad hoc network is interference limited, the power control strategy plays an important role in the study of transmission capacity. In this paper, a well-known power control strategy, i.e., channel inversion, is studied. By comparing with no power control case, we found that using channel inversion increases the level of normalized interference in network, which makes the performance of network worse. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A context-aware autonomic packet marking mechanism

    Publication Year: 2009 , Page(s): 38 - 43
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (260 KB) |  | HTML iconHTML  

    Autonomic network is an important research field in network architectures. Since autonomic attributes such as context-aware, self-configuration, self-optimizing and self-management are introduced, autonomic network is capable of adapting to the heterogeneous and complex network environments. In this paper, context-aware and autonomic mechanisms are introduced into the DiffServ QoS framework and a novel context-aware autonomic packet marking mechanism (CAPM) is proposed. CAPM is capable of collecting various QoS related contexts, and adaptively adjusting network behavior to provide QoS guarantee according to users' QoS requirements and network conditions. Simulation results show that CAPM provides better performance than traditional packet marker, and improves user's quality of experience. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Study and analysis of network delay by simulation

    Publication Year: 2009 , Page(s): 44 - 47
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (93 KB) |  | HTML iconHTML  

    Presently, It is paid much attention to network performance, as a main criterion, delay is becoming more and more important. A network model for a certain network is built by simulation software. It analyses the relations among delay, throughput, user number and bandwidth. Then it points out the direction to decrease the network delay by simulation and it can optimize the network performance with the simulation model in the future. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimizing multi-path routing by avoiding Key Nodes

    Publication Year: 2009 , Page(s): 48 - 51
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (152 KB) |  | HTML iconHTML  

    In this paper, we propose a new routing algorithm which combines source routing and intermediate routing in order to meet the requirement of node disjointed path and scalability. We also discover the existing of key nodes which we call KN, KN are the transmission congestion host spots, also in multi-path routing, they will lead to a low performance in disjointed path. We give a simple, effective method to detect KN and avoid them. The result of simulation shows that this method can obtain a good performance on disjointed path, and can significantly improve network reliability. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Probability of packet success of ad hoc networks with sib based power control

    Publication Year: 2009 , Page(s): 52 - 56
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (96 KB) |  | HTML iconHTML  

    Probability of packet success of ad hoc networks is determined by two factors, one is the probability of successful transmission at the receiver, and the other is the probability of successful detection at the detector. In this paper, we study the probability of successful transmission by using the Poisson model with SIR based power control. Taking direct sequence scheme with binary phase shift keying for example, the expression to the probability of packet success is derived. For the exact expression to the probability of packet success can not be obtained, we provide the asymptotic expression. Finally, the performance of probability of packet success and the accuracy of asymptotic expression are studied by using simulation and numerical results. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Study on mobility models in vehicular communication system

    Publication Year: 2009 , Page(s): 57 - 61
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (223 KB) |  | HTML iconHTML  

    Vehicles equipped with wireless communication devices are poised to deliver vital services in the form of safety alerts, traffic congestion probing and on-road commercial applications. The selection of the most realistic and the most easy-to-implement mobility model is very crucial for the validity and feasibility of research. It is described several mobility models that represent mobile nodes whose movements are independent of each other below. Based on Manhattan mobility model and no-boundary simulation region mobility model, a vehicular mobility model is proposed for ad hoc network. While vehicular simulator has been developed under the vehicular communication system, it is important to use realistic traffic density, speed, trip, and communication models. The simulation shows that the vehicular mobility model suits the vehicular communication environment suppose. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A norvel power allocation algorithm under CoMP with CA

    Publication Year: 2009 , Page(s): 66 - 70
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (143 KB) |  | HTML iconHTML  

    3GPP LTE specification is stable now in release 8. To meet much higher requirements than release 8, 3GPP has initiated the LTE-A (LTE-Advanced) study item. In LTE-A, CoMP (coordinated multiple point transmission and reception) and CA (carrier aggregation) are two new features. CoMP is used to improve coverage and to increase cell-edge throughput. It is considered as an effective approach for ICIC (inter-cell interference coordination) in LTE-A due to inherent joint scheduling/processing at the coordinated cells. CA is used to improve the peak rate in LTE-A. It has been widely discussed in 3GPP RAN1. Generally, three kinds of CA are involved, namely the aggregations for continuous carriers, non-continuous intra-band carriers and non-continuous inter-band carriers respectively. In this thesis, under the case of CA, the problem of power allocation for eNBs in the CoMP cooperating set for downlink transmission is discussed, and we propose a power allocation algorithm. Based on the system simulation, the unite rate (bit/sec/Hz) and the corresponding SINR are compared. The possible method of the implementation for this scheme is discussed too. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A buffer level clock recovery based on least mean squares in PTN

    Publication Year: 2009 , Page(s): 71 - 74
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (125 KB) |  | HTML iconHTML  

    Packet transport network (PTN) supports multiple services, including legacy TDM service. Clock recovery mechanism is essential technology for TDM over packet networks. As the buffer level clock recovery method in PTN is highly sensitive to the packet delay variation (PDV), a buffer level clock recovery based on least mean squares (LBL) is proposed. Simulation results show that LBL can effectively remove the negative contribution of packet delay jitter and provide more accurate clock recovery at the destination than traditional scheme. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Sub-carriers bidirectional arrayed handover algorithm

    Publication Year: 2009 , Page(s): 75 - 79
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (125 KB) |  | HTML iconHTML  

    Orthogonal Frequency Division Multiple Access (OFDMA) has already been the main multiple access technology for 3G long term evolution(LTE) and 4G. This paper analyzes characteristics of OFDMA multiple access technology and puts forward a new OFDMA handover algorithm (sub-carriers bidirectional arrayed handover algorithm, SBA). The simulation results show that, during handover process, SBA algorithm proposed in this paper guarantees users in OFDMA system keeping the best channel SIR and QoS. Moreover, SBA algorithm decreases the extra consumption of the handover, and improves OFDMA system performance. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Duplicate-aware opportunistic routing for multi-hop wireless networks

    Publication Year: 2009 , Page(s): 80 - 84
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (86 KB) |  | HTML iconHTML  

    Recently, opportunistic routing has been proposed to take good advantage of broadcast nature and spatial diversity to achieve high throughput, despite highly unpredictable and lossy wireless links in multi-hop wireless networks. Most previous works provide heuristic solutions to select as many candidates, and don't take inter-candidate delivery probability into account, which might suffer acknowledgement loss and lead to duplicate forwarding, ultimately degrades network throughput. In this paper, a discrete-time Markov model is firstly presented to analyze duplicate forwarding probability at the candidates, and then simple candidates optimization algorithm and acknowledgement enhancement mechanism are proposed to eliminate the effect of duplicate forwarding. Simulations are conducted to verify our algorithm, and results show that there is a 20% gain in throughput when compared with traditional opportunistic routing protocol. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An autonomic flow based path selection method for multi-homed nodes

    Publication Year: 2009 , Page(s): 85 - 89
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (95 KB) |  | HTML iconHTML  

    In order to access the Internet ubiquitously, most of the devices are equipped with multiple radio interfaces. In this way, the multi-homed node can attach to multiple access networks through multiple communication paths simultaneously. Flow based path selection is typically needed for the user to be always best connected. Meanwhile, autonomic feature can be introduced into the path selection system. An autonomic flow based path selection system is proposed in this paper to autonomically and efficiently select the best communication path for the traffic flows of the multi-homed node. The generated routing rules can constrain specific traffic flow to certain communication path properly and simultaneously. In the end, the throughput of the multi-homed nodes is verified in our simulation scenario to evaluate the performance of the path selection method. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Efficient data collection in wireless sensor networks by applying network coding

    Publication Year: 2009 , Page(s): 90 - 94
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (100 KB) |  | HTML iconHTML  

    Considering a wireless sensor network with optimal mobile sink track along which data are transmitted to the nodes, a fraction of nodes in the area of interest generate data packets and send them to the sink. Usually the single path routing is adopted in such scenarios which may cause unnecessary transmissions. We address the problem of how to collect these packets efficiently by using network coding technique. Network coding is a kind of in network computation which has many advantages over traditional routing, such as providing higher network throughput, using bandwidth efficiently and balancing the traffic. In this paper, we propose a data collection strategy by using network coding for efficient data collection in event driven WSNs and explore its performance through theoretical analysis. We present a strategy for network coding algorithm which can guarantee the successful decoding for all the encoded packets. Specifically, our numerical results show the decrease in the total number of transmissions by applying network coding than that by using the single path routing. Also numerical results indicate that the delivery packets rate is significantly improved as the increase of the link loss rate comparing network coding we adopt with single path routing. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The effect of human activites on 2.4 GHz radio propagation at home environment

    Publication Year: 2009 , Page(s): 95 - 99
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (106 KB) |  | HTML iconHTML  

    As the technology evolves, Wireless Sensor Networks (WSNs) for home environment, such as healthcare systems, can be designed using low-cost, low-power and short-range radio equipments in 2.4 GHz ISM Frequency-band. While a great deal of efforts have been paid for studying the radio fading caused by human body in WLAN or cellular-systems, however, the comprehensive effects of the human mobility on WSNs radio propagation for indoor environment remain unexplored widely. In this paper, we investigate the effects of human activities on the radio propagation of wireless sensor networks at home, based on the experimental measurements. Our results show that these factors have significantly effect on the receive radio signal strength. We also propose an improved radio propagation model to characterize the mobility of people for the effects of indoor radio propagation of wireless sensor networks. As an example, the random way point model is employed as the mobility model. The evaluation results show that our model performs better coherence with the measurement results. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Fairness evaluation of the default highspeed TCP in common operating systems

    Publication Year: 2009 , Page(s): 100 - 105
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (207 KB) |  | HTML iconHTML  

    Since the TCP protocol implements in the Internet, the AIMD algorithm has always been the dominating congest control algorithm for about 20 years, and most of the common operating systems follow the recommendation of the IETF to adopt the AIMD algorithm in their TCP variations. But in recent years, many high-speed congest control algorithms have been proposed for fast data transfer over high speed and long distance networks, and many operating systems take the high-speed TCP variations as default: the Linux kernel uses CUBIC TCP as default since version 2.6.18, while Compound TCP becomes default TCP in Windows Server 2008 and a part of Microsoft Windows Vista, where it is easy to be enabled. As there are still not sufficient and comprehensive performance comparison of the high-speed TCP variations, the deployment of them as default TCP in the operating systems raises concerns about the future of congest control in the internet and worries about the fairness problem. This paper is an attempt to evaluate the fairness of the default TCP in the newest Linux and Microsoft Windows. The simulation results indicate that between CUBIC TCP and Compound TCP it indeed exhibits unfairness. The CUBIC TCP is too aggressive to the Compound TCP in the high bandwidth-delay product network, and the performance of Compound TCP is unacceptable comparing to CUBIC TCP. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comprehensive-factors-based scheduling algorithm for P2P media streaming

    Publication Year: 2009 , Page(s): 111 - 116
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (226 KB) |  | HTML iconHTML  

    A comprehensive-factors-based (CFB) scheduling algorithm is proposed for peer-to-peer media streaming. In CFB, considering the number of chunks' suppliers and urgency, a priority is defined for each data chunk and the neighbours' bandwidth is effectively evaluated. A peer requests chunks from neighbors according to priorities as well as bandwidth. Simulation results show that the proposed CFB scheduling algorithm for Peer-to-Peer media streaming outperforms conventional scheduling algorithms in peer average throughput, continuity index and start delay. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.