Ethernet passive optical network (EPON) time synchronization method



The invention discloses an Ethernet passive optical network (EPON) time synchronization method. An optical line terminal (OLT) side of an EPON realizes a peer to peer (PTP) sub clock. The method comprises the following steps that: a PTP timestamp counter is read through a central processing unit (CPU) at the OLT side; the CPU calculates the corresponding ToD and the PTP timestamp counter value corresponding to the latest one 1PPS; the obtained PTP timestamp counter value is set to a 1PPS PTP timestamp counter register; an OLT multipoint control protocol (MPCP) timestamp counter is latched into the 1PPS PTP timestamp counter register; the CPU reads the 1PPS PTP timestamp counter register; the CPU sends the information to an optical network unit (ONU) through operation and maintenance (OAM) messages; and the ONU side realizes the IPPS+ToD information output. The time synchronization method can simply and flexibly realize the time synchronization technology.
本发明公开了一种EPON网络时间同步的方法,该EPON网络的OLT侧实现了PTP从时钟,该方法包括如下步骤:OLT侧通过CPU读PTP时戳计数器;CPU计算最近一个1PPS对应的PTP时戳计数器值及对应ToD;将所得PTP时戳计数器值置于1PPS PTP时戳计数器的寄存器;将OLT MPCP时戳计数器值锁存在1PPS MPCP时戳计数器值寄存器内;CPU读1PPS MPCP时戳计数器的寄存器;CPU将上述信息通过OAM报文发送给ONU;ONU侧实现1PPS+ToD信息输出。本发明的时间同步方法,可以简单灵活地实现时间同步技术。




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Patent Citations (4)

    Publication numberPublication dateAssigneeTitle
    CN-101213782-AJuly 02, 2008泰克诺沃斯公司在以太网无源光网络中适应不同时钟频率
    CN-101431385-AMay 13, 2009中兴通讯股份有限公司Frequency and time synchronization method for passive optical network
    CN-101615949-ADecember 30, 2009中国移动通信集团上海有限公司实现毫微微蜂窝基站时钟同步的方法、系统及设备
    US-2008031283-A1February 07, 2008Martin Curran-Gray, Jeff Burch, Ilnickl Slawomir LTime synchronization for network aware devices

NO-Patent Citations (0)


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    Publication numberPublication dateAssigneeTitle