Direct attach copper cables have the edge over both SMF and MMF fiber when it comes to latency, and this is even more prominent for short cable runs because of the latency introduced by the SFP modules which drive the fiber. If you really care about latency, (twinax) copper is faster than fiber .
Read moreWhat is the latency of a fiber optic cable?
Because light travels approximately 1.5 times slower through optical fiber than in a vacuum, the latency is 5 µsec per kilometer . The number 1.5 is referred to as the Index of Refraction and will vary slightly based on the wavelength of light being propagated and composition of the optical fiber.
Read moreDoes fiber have less latency?
For longer distance transmission, fiber cable offers lower latency for the whole network and can be an optimal choice.21 Eki 2017
Read moreDoes Fibre reduce latency?
The answer to the cable vs fiber debate is that, in general, fiber connections are better for gaming as they offer faster downloads and a higher-quality connection with lower latency and jitter.18 Mar 2018
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