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Precise Latency Measurement of Unidirectional-Data-Flow Network Equipment
Published
Author(s)
I-Chun Chao, Kang B. Lee, Frederick M. Proctor, Chien-Chung Shen, Fan-Ren Chang
Abstract
In regards to network performance measurements, many timing indices, such as latency, jitter, and one-way delay (OWD), are getting more attention because real-time applications and needs are pushing higher network capabilities. Data latency in a network can be measured by placing additional unidirectional-data-flow (UDF) devices, such as test access taps (TAPs), on the network path. However, this can create severe uncertainty to the timing measurement when sub-microsecond precision measurements need to be achieved. This paper proposes the Precision Time Protocol (PTP)-Based Measurement method for measuring latency of a UDF device based on traditional OWD measurements. In addition, we propose a Packet-by-Packet Precise Measurement method, which can further reduce the measurement uncertainty caused by the limit of precision in the PTP synchronization protocol in the PTP-Based Measurement method, by strictly calculating the latency for each packet.
Proceedings Title
2014 IEEE International Frequency Control Symposium
Chao, I.
, Lee, K.
, Proctor, F.
, Shen, C.
and Chang, F.
(2014),
Precise Latency Measurement of Unidirectional-Data-Flow Network Equipment, 2014 IEEE International Frequency Control Symposium, Taipei, TW, [online], https://doi.org/10.1109/FCS.2014.6859840, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=915793
(Accessed October 8, 2025)