New wireless sensor network applications (e.g., military surveillance) require higher reliability than a simple best effort service could provide. Classical reliable transport protocols like Transmission Control Proto...New wireless sensor network applications (e.g., military surveillance) require higher reliability than a simple best effort service could provide. Classical reliable transport protocols like Transmission Control Protocol (TCP) are not well suited for wireless sensor networks due to both the characteristics of the network nodes (low computing power, strong energy constraints) and those of the main applications running on those nodes (low data rates). Recent researches present new transport protocols for wireless sensor networks providing various type of reliability and using new mechanisms for loss detection and recovery, and congestion control. This paper presents a survey on reliable transport protocol for WSNs.展开更多
This paper presents a streaming system using scalable video coding based on H.264/AVC. The system provides a congestion control algorithm supported by channel bandwidth estimation of the client. It uses retransmission...This paper presents a streaming system using scalable video coding based on H.264/AVC. The system provides a congestion control algorithm supported by channel bandwidth estimation of the client. It uses retransmission only for packets of the base layer to disburden the congested network. The bandwidth estimation allows for adjusting the transmission rate quickly to the current available bandwidth of the network. Compared to binomial congestion control, the proposed system allows for shorter start-up times and data rate adaptation. The paper describes the components of this streaming system and the results of experiments showing that the proposed approach works effectively for streaming video.展开更多
分析了通用数据传输服务质量(quality of service,QoS)技术,探讨了实时传输及实时传输控制协议(real-time transport protocol/real-time transport control protocol,RTP/RTCP)、H.264分层编码与码率控制、信道自适应的传输等相关技术...分析了通用数据传输服务质量(quality of service,QoS)技术,探讨了实时传输及实时传输控制协议(real-time transport protocol/real-time transport control protocol,RTP/RTCP)、H.264分层编码与码率控制、信道自适应的传输等相关技术在跨层视频传输过程的作用,指出自适应多速率(adaptive multirate auto rate fallback,AMARF)协议的缺陷,提出改进的E-AMARF(Extend-AMARF)协议并进行仿真实验,基于以上技术提出一种跨层视频传输QoS控制策略,并将其应用于本团队自主研发的无线局域网可视电话(WLAN video phone,WVphone)终端上。仿真实验表明,在节点数目不多时,E-AMARF协议相较AMARF协议具有明显的优越性。WVphone终端测试结果显示,添加QoS保障后,WVphone具有实时、高清的效果,说明本跨层视频传输QoS控制策略是有效的。展开更多
文摘New wireless sensor network applications (e.g., military surveillance) require higher reliability than a simple best effort service could provide. Classical reliable transport protocols like Transmission Control Protocol (TCP) are not well suited for wireless sensor networks due to both the characteristics of the network nodes (low computing power, strong energy constraints) and those of the main applications running on those nodes (low data rates). Recent researches present new transport protocols for wireless sensor networks providing various type of reliability and using new mechanisms for loss detection and recovery, and congestion control. This paper presents a survey on reliable transport protocol for WSNs.
文摘This paper presents a streaming system using scalable video coding based on H.264/AVC. The system provides a congestion control algorithm supported by channel bandwidth estimation of the client. It uses retransmission only for packets of the base layer to disburden the congested network. The bandwidth estimation allows for adjusting the transmission rate quickly to the current available bandwidth of the network. Compared to binomial congestion control, the proposed system allows for shorter start-up times and data rate adaptation. The paper describes the components of this streaming system and the results of experiments showing that the proposed approach works effectively for streaming video.
文摘分析了通用数据传输服务质量(quality of service,QoS)技术,探讨了实时传输及实时传输控制协议(real-time transport protocol/real-time transport control protocol,RTP/RTCP)、H.264分层编码与码率控制、信道自适应的传输等相关技术在跨层视频传输过程的作用,指出自适应多速率(adaptive multirate auto rate fallback,AMARF)协议的缺陷,提出改进的E-AMARF(Extend-AMARF)协议并进行仿真实验,基于以上技术提出一种跨层视频传输QoS控制策略,并将其应用于本团队自主研发的无线局域网可视电话(WLAN video phone,WVphone)终端上。仿真实验表明,在节点数目不多时,E-AMARF协议相较AMARF协议具有明显的优越性。WVphone终端测试结果显示,添加QoS保障后,WVphone具有实时、高清的效果,说明本跨层视频传输QoS控制策略是有效的。