A beam splitter has several functions in splitting ports

A beamsplitter is a common optical component that partially transmits and partially reflects an incident light beam, usually in unequal proportions. a laser beam) into two (or sometimes more) beams, which may or may not have the same optical power (radiant flux). For our purposes it can simply be viewed as a device that has two input and two output ports, which we label with ∣ 0 ⟩ ∣0⟩ and ∣ 1 ⟩ ∣1⟩. The beam splitter has played numerous roles in many aspects of optics. [pdf]

How many ports are there in the fiber optic terminal box

This Fiber MST Box offers diverse connectivity with 8 ports, each supporting single-mode G. As a professional fiber optical terminal box manufacturer, UnitekFiber provides fiber terminal boxes with various waterproof levels, up to IP68; and provides a variety of options from 2 ports to 48 ports. Fiber optic terminal boxes are widely used in telecom rooms, corridors, FTTH and other. The FTTX Pre-connectorized Terminal Boxes, available in 8 Ports (HTB8066-8), 10 Ports (HTB8066-10), and 12 Ports (HTB8066-12), are high-performance fiber management solutions designed for FTTx network systems. It can be seen almost everywhere. With OEM/ODM. Many buyers assume “capacity” simply means the number of adapter ports on the front panel (for example, 8 ports or 16 ports). [pdf]