Adaptation of the N-GREEN Architecture for a Bursty Traffic

Analysis of a Frequency Response of a Noisy Optical Network for Its Self-adaptation

“…We have chosen an experimental optical network of an average complexity of packet management-an NGREEN ring of coloured packets [6]. It is normally predestined to be used in metropolitan aggregation networks based on 5G [12], but due to its low cost, an adaptation to a bursty traffic found, e.g., in data centres is considered [4]. We will improve that adaptation by the said tuning of tuning-one of the strategy-regulating coefficients which is normally constant will oscillate.…”

“…We will briefly describe the traits of the architecture relevant to the topic of this paper, and the details can be found in [4]. We simulate an unidirectional optical ring divided into M = 1000 fixed-size slots of S = 12,500 bytes each.…”

“…Along the ring, there also exists a bidirectional control channel, which allows the nodes to exchange some control information or statistics. The channel is essential for the optimisation method presented in [4]-it turns out that if each node broadcasts in the two available directions and in each 1 μ s its momentary electronic input queue size, an effective optimisation can be employed called there GLOBAL. The name comes from the fact that each node N i uses global, if delayed information about the momentary size in bytes of input queues S j , j = 1, … N of all nodes along the ring, and not only its own local information about S i .…”

“…As we talk about a constant adaptation of strategy in noisy conditions, let us make the traffic model very variable, much more variable that a bare CAIDA trace [5] used in [4]. We will make a mixture of two very different CAIDA traces and for contrast, of a node-symmetric traffic given (2)…”

“…To estimate the robustness of the loop control methods in question, here, we test the quality of a frequency-domain response on a highly noisy model of an experimental optical network NGREEN [4,6], facing constant traffic change. A sinusoidal perturbation of the system constantly introduces small modifications into a main, strategy of self-adaptation of the network [4] which already contains its own feedback mechanisms. Possible resulting oscillations in the quality of the behaviour of the system are then detected, a response useful in loop control algorithms like the widely known Ziegler-Nichols method.…”