A kind of packet reordering analysis model in concurrent multipath transmission
Tao Yang, Jiayong Zhang, Xuanrui Xiong · Advances in engineering research/Advances in Engineering Research · 2016
Focus on the problem of packet reordering in concurrent multipath transmission which lead to an unnecessary fast retransmit and increase in network load, reduces the utilization of network resources.This paper put forward a kind of packet reordering analysis model in concurrent multipath transmission based on the cumulative probability distribution function, besides, a constraint conditions are derived for data packets to be transmitted in order.And the calculation formula of random order probability of data packet in concurrent multipath transmission. 1IntroductionIn the scene of the concurrent multipath transmission, even in a ideal situation, it is assumed that the upper application with rapid processing capacity of data packet arriving at the receiving end, the phenomenon of packet reordering will also unavoidable.The research in this field now is mainly to make a modeing analysis of the transmission performance of concurrent multipath transmission system in the packet reordering.And this will provide theoretical reference of improving the performance of concurrent multipath transmission system to further reduce the disorder phenomenon.This paper make a deep research of packet reordering problem in concurrent multipath transmission system, put forward a more reasonable packet reordering analysis model.Compare to the existing research, this model take the queue delay and transmission delay into account in order to increase the accuracy and validity of the model. Research on packet reordering problem in concurrent multipath transmission system Definition of packet reordering Section Headings.The RFC4737[1] had given a definition of packet reordering, and developed a variety of the evaluation criterias to quantify the severity of the disorder.Packet reordering is defined as follows: S: Transmission serial number of the sending end assigned to the data packet; I: The serial number of the data packet that the receiving end receives; s[i]:The No.i group transmission serial number that the receiving end receives; j: The smallest integer satisfying the condition of s[j] > s[i] in the top i group that the receiving end receives, besides, j < i;If s = i, then the No.i packet is received at a sequence, and packet reordering is not occurred; Otherwise, if s ≠ i, then packet reordering is occurred when the receiving end received the No. i packet, we use "e" to express the reordering degree of group s[i]. Reason of packet reorderingIn heterogeneous network environment, the path used in concurrent multipath transmission may belong to different access networks, the different network characteristics lead to transmission delay and bandwidth differences in different paths, The packets on the path of the smaller delay will reach the receiving end earlier than the other paths.The packets arrives early could not be processed in order to the upper application, This part of the packet will be stored in the buffer zone of the receiving