... the machine without termination resistor provided, please press the need for external.Optical interface Ø Optical wavelength: Multi-mode 850nm, 1310nm; ... , two optical interface, DIP switch set the rate, use for chain, star, ring, and other network structure, multi-mode fiber 0 ... , two optical interface, DIP switch set the rate, use for chain, star, ring, and other network structure, multi-mode fiber 0 ...