发明名称 |
NETWORK TIME PROTOCOL PRECISION TIMESTAMPING SERVICE |
摘要 |
Embodiments of the present invention set forth a method and system for reducing uncertainty in receive and transmit timestamps created by an NTP server. The uncertainty in the receive timestamps is removed by recording the time-of-arrival in the hardware clock of the NTP server before the incoming packets may be delayed by traversing the various layers of software in a timestamping system. The uncertainty in the transmit timestamps is removed by giving the outgoing packets a timestamp in the future using an estimate of the transmission latency calculated by the latency estimator filter. Subsequently, the actual time-of-departure is used to re-calculate and update the estimate of the transmission latency. In this fashion, superior control of the timestamping function may be implemented in existing NTP servers in a manner that retains interworking compatibility with the current NTP standards. |
申请公布号 |
WO2007137085(A3) |
申请公布日期 |
2008.01.24 |
申请号 |
WO2007US69066 |
申请日期 |
2007.05.16 |
申请人 |
SYMMETRICOM, INC.;DOWD, GREGORY, LOUIS |
发明人 |
DOWD, GREGORY, LOUIS |
分类号 |
H04L12/28;H04J3/06 |
主分类号 |
H04L12/28 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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