A wiring closet is a small room commonly found in institutional buildings, such as schools and offices, where electrical connections are made. While they are used for many purposes, their most common use is for computer networking. Many types of network connections place limits on the distance between end user equipment, such as personal computers, and network access devices, such as routers. These restrictions might require multiple wiring closets on each floor of a large building.http://www.mtholyoke.edu/lits/network/infrastructure/closet.html

Equipment that may be found in a wiring closet includes:

• Alarm systems
• Circuit breaker panels
• Video systems, such as cable TV and closed-circuit television
  Closed-circuit television
  Closed-circuit television is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors....
  
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• Ethernet routers
• Fiber optic terminations
• Patch panel
  Patch panel
  A patch panel or patch bay is a panel, typically rackmounted, that houses cable connections. One typically shorter patch cable will plug into the front side, whereas the back holds the connection of a much longer and more permanent cable...
  
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• Telephone
  Telephone
  The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...
  
   punch block
  Punch block
  A punch down block is a type of electrical connection often used in telephony. It is named because the solid copper wires are "punched down" into short open-ended slots which are a type of insulation-displacement connectors...
  
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• Wireless access point
  Wireless access point
  In computer networking, a wireless access point is a device that allows wireless devices to connect to a wired network using Wi-Fi, Bluetooth or related standards...
  
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