When a received SACK option needs to be processed, the TCP stack must find the packet ( s) in the retransmission queue that the SACK applies to. 当需要处理一个收到的SACK选项时,TCP协议栈必须在重传队列中找到应用了SACK的包。
The simulation results show that the proposed approach can reduce the number of retransmission, and improve the efficiency of packet retransmission and retrievement compared with existing approaches. 仿真结果表明该方法相比已有算法能有效地减少重传次数,并提高重传包发送和接收的效率。
After failing to send a packet, the backoff interval was gradually shortened when times of retransmission increased. 报文发送失败时,随着报文重传次数增加,逐渐减小退避间隔,实现报文的重传。
The transmission performance, including average throughput, average retransmission times and average transmission delay, of all data packets in different SNRs are investigated through the packet retransmission probability and different characteristics of packets. 通过分组重传概率与分组的不同特性分析了不同信噪比情况下各类型数据分组的传输性能,包括平均吞吐量、平均重传次数、平均传输时延等。
In this paper, a new packet loss recovery mechanism based on retransmission is presented, which can effectively recover the lost packets in multimedia multicast and reduce the effect from delay variation on multimedia flow playback. 本文提出了一种基于本地重传的多媒体组播自适应包丢失恢复机制,在实现包丢失恢复的同时,能有效消除时延抖动的影响。
Relations between bit error rate and average received signal-to-noise ratio ( SNR) in AWGN channel were derived for three modulation modes defined by Bluetooth 2.0+ EDR new specification. The function expressions of packet retransmission probability and average received SNR of ACL packets were put forward. 分析了蓝牙2.0+EDR新规范定义的3种调制方式在AWGN信道下的位错误率与平均接收信噪比的关系,推导了ACL分组的重传概率与平均接收信噪比的函数表达式。
The stability link has higher packet delivery ratio, thereby reducing the number of packet retransmission, and has a long maintenance time, thereby reducing the happenes of link breakdown and the maintenance overhead of the protocol. 稳定的路径具有较高的分组投递率,从而降低了分组重复发送次数,并且链路维持时间长,减少了断路发生,降低了协议的维护开销。
This approach reduces the number of packet retransmission, and improves the network packet delivery ratio. 这种方法减少了分组的重发次数,也提高了网络的投递率。
RTP defines simple encapsulation of streaming media data, without error checking and loss packet retransmission. So it has high transmission efficiency, low delay, and it offers sequence number and timestamp for receiver to reconstruct and synchronize the data. RTP对流媒体数据进行简单的封装,不进行错误检测和丢包重传,因此传输效率高、延时小,而且它提供了序列号和时间戳以便接收端进行数据重组和同步。
According to this concept, a series of strategies was proposed, including disorder restructuring, jitter cancellation, lost packet retransmission, bitrate self-adaptation, and lip sync strategy. 本文首次提出了广义的视讯产品网络自适应性的概念,按照这一概念设计了一系列实用的策略,具体包括乱序重排、去抖动、丢包重传、码率自适应和唇音同步策略。
And the thesis also provides appropriate strategies of path selecting and packet scheduling. Firstly, a strategy of SCTP-CMT transmission and retransmission based on bandwidth estimation are provided from the point of view of path selecting. 提出了相应的路径选择和数据包调度策略。首先,从路径调度角度提出了一种基于带宽测量的SCTP-CMT传输和重传策略。
Likewise, the received packet in each retransmission is different due to that the multiple access interference, noise and fading are random and time-variant. 由于多址接入干扰、噪声和衰落都是随机时变的,因此每次接收到重传的数据包信号是不相同的。
However, because of the poor conditions of wireless channel, it is more likely to have packet loss, collisions, and retransmission and so on. 然而,由于无线信道的通信条件十分恶劣,所以时常会出现碰撞、丢包、重传等情况。
The traditional congestion control algorithms judge the congestion occurrence through the following ways: when packet is discarded, sender will receive greater than or equal to three repeated ACKs, or timeout of retransmission timer. 传统拥塞控制算法是通过丢弃数据包后,使发送端通过收到大于等于三个重复的ACK或者重传计时器超时的方式隐式的判断拥塞的发生。
Using the signal analysis system discovered core network equipment SGSN, GGSN exist problems of packet delay longer, and retransmission rate larger, after in targeted adjustments related parameters of the core network the problem solving. 利用信令分析系统的各接口综合分析功能发现了核心网设备SGSN、GGSN存在数据包时延较长、重传率较高的问题,在有针对性的调整核心网网元的相关参数后问题得到解决。
However, the adjacent nodes in the shared channel can easily cause collision in data transmission, this not only leads to increase packet loss but also increases the delay and energy consumption caused by retransmission. 然而,相邻节点间共享信道极易引起收发数据的冲突,这样不仅引起分组丢失而且增大了由重传导致的时延和能量消耗。