Service information sending, receiving method and apparatus, sequential number synchronization system

Abstract

The embodiment of the invention relates to a method and a device for sending and receiving service information, and a serial number synchronization system, wherein the method for sending the service information comprises the following steps that: a sending end and a receiving end negotiate whether the blank frame interaction is supported; the sending end sets the state of a blank frame identifieraccording to a negotiation result, wherein if the sending end and the receiving end both support the blank frame interaction, the state of the blank frame identifier is set as an effective state; andwhen the sending end performs the switching between an active main control board and a standby main control board, the state of the blank frame identifier is identified, and a blank frame is sent to the receiving end when the state of the blank frame identifier is the effective state. The method and the device for sending and receiving the service information and the serial number synchronizationsystem ensure that the receiving end can identify the blank frame sent by the sending end, and quickly realize the serial number synchronization between the sending end and the receiving end when thesending end performs active-standby switching.

Description

technical field [0001] 本发明涉及通信技术,尤其涉及一种业务信息发送、接收方法和装置、顺序号同步系统。 Background technique [0002] 多链路点到点协议(Multi-link Point-to-Point Protocol,以下简称:MLPPP)通过将多个独立的物理链路捆绑成一条逻辑链路,实现了两个固定的端点间更大的逻辑传输带宽。 为了支持上述较大逻辑传输带宽以及满足各物理链路最大接收单元(Maximum Receive Unit,以下简称:MRU)的具体要求,每个物理链路的发送端有一个切片模块,接收端有一个重组模块,发送端的切片模块将长的协议数据单元(Protocol Data Unit,以下简称:PDU)采用切片的方式切成多个分段数据(fragment data),将分段数据封装成MLPPP帧进行传输。 Such as figure 1 所示,为现有技术中MLPPP帧的格式示意图,包括点到点协议(Pont-to-Point Protocol,以下简称:PPP)头、MLPPP头和PPP校验序列(Frame Check Sequence,简称:FCS);其中,PPP头包括地址域(Address)、控制域(Control)和协议标志符(Protocol Identification,简称:PID),MLPPP头包括开始(B)、结束(E)、分段数据以及为该分段数据分配的顺序号(Sequence Number)。其中,与PDU的第一个分段数据对应的B设置为1,与PDU的其他分段数据对应的B设置为0,与PDU的最后一个分段数据对应的E设置为1,与PDU的其他分段数据对应的E设置为0,如果只有一个分段数据,则B和E都设置为1;顺序号可以是一个24bit或12bit的字段。发送端严格按顺序发送MLPPP帧,将发送的MLPPP帧的顺序号依次增加1,发送端发送的所有MLPPP帧的顺序号是连续的。若所有MLPPP帧在各个物理链路上的传输时间相同,则MLPPP帧按照发送顺序到达接收端。然而,由于各个物理链路的传输条件不同,MLPPP帧在各个物理链路上的传输速度也不同,导致MLPPP帧无法按照发送顺序到达接收端。接收端接收到MLPPP帧以后,将接收到的MLPPP帧放入重组窗口中,将重组窗口中从B=1到E=1的MLPP...

AI Technical Summary

Problems solved by technology

[0006] In the state that the receiving end does not support empty frames, the single-ended sending of empty frames by the sending end may cause abnormal processing at the receiving end, and the receiving end cannot recognize empty frames, so the receiving end The end cannot quickly fill up the reassembly window and discard it so as to realize the rapid synchronization of the sequence numbers of the sending end and the receiving end, which will also cause the receiving end to wait too long and cause communication protocol timeout interruption

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