TIR stands for Total Internal Reflection and it can be used for means of communications via internet or broadband. Also, it can be used for different kinds of Surgery.
This seems like a question from an electrical course, and is probably best answered by your course materials.
It's your test question, not ours, and there won't always be someone to ask for the...
Short-haul customers include universities, institutions, corporations, hotel chains, hospitals, local area networks, cellular phone networks, and local governments