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Telecom demand was down while datacom module demand, particularly Ethernet optics, was up in the first half of the year, LightCounting points out. The two markets switched direction in the second half, however (see chart above). Meanwhile, sales of wavelength-selective switch (WSS) modules, EDFAs, pump lasers, and passive components, not included in the above chart, were strong all year. As these products tend to be used early in network deployments, LightCounting takes the strong demand for such devices as a good sign for telecom optical transceiver demand in 2019. For example, 25G optical transceivers for 5G mobile were sold well in 2018, a trend LightCounting expects to continue this year.
On the datacom front, positive signs for 2019 include Google’s recently announced plans to spend $13 billion on data center construction this year .Facebook’s newly announced F16 data center network design also implies an increase in demand for 100 Gigabit Ethernet connectivity as well, LightCounting believes.