Traditional optical fiber has a single core at its center. The number of optical cores in an optical fiber is the total number of equipment interfaces multiplied by 2, plus 10% to 20% of the spare quantity, and if the communication mode of the equipment has serial communication and equipment multiplexing, you can reduce the number of cores. When selecting fiber, the first step is to determine single mode or multimode, and. Multi-core fiber (MCF) is an advanced optical fiber technology that embeds multiple light-guiding cores within a single fiber cladding, enabling far greater capacity than traditional fibers.