TITLE:
Determination of the Upper Limit of the Delay in the XG-PON Network
AUTHORS:
Akanza Konan Ricky N’dri, Nouho Ouattara, Jean Edgard Gnimassoun
KEYWORDS:
Delay Approach, Hypothesis Test, Normal Distribution, Upper Bound of Delay
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.15 No.9,
September
12,
2025
ABSTRACT: One of the optimization solutions in XG-PON networks is the proposal of an efficient bandwidth allocation algorithm that impacts other Quality of Service (QoS) parameters such as delay, jitter, and packet loss. However, a better allocation algorithm alone is not sufficient to guarantee delay, and maintaining it within a certain limit remains a challenge. In XG-PON networks, delay is defined as the time a packet spends from its arrival in the Optical Network Unit (ONU) buffer until its transmission to the Optical Line Terminal (OLT). It requires special attention, especially since this network offers delay-sensitive services such as videoconferencing, telemedicine, and IPTV. This article aims to determine the upper bound of the delay, i.e., a delay that cannot be exceeded by packets as long as the network does not experience failures. By creating our dataset using the simulation log file of the XGPON network module, we calculate certain parameters, such as the inter-arrival time of packets, the arrival rate in the ONU buffer, the service rate, the bandwidth service time by the OLT, and the transmission time (departures) of packets from the ONU to the OLT. From these parameters, we propose a delay approach by linking cumulative arrivals A(t), cumulative services S(t), and cumulative departures D(t). Using a hypothesis test to find the critical rejection region, we determine the upper bound of the delay that packets should not exceed. This limit is set at 3 ms and is validated by exact queuing theory models.