The first one
An unwanted transfer of signals between communication channels
What is Crosstalk?
Has a grounded outer copper shield around the bundle of twisted pairs or around each pair. This provides added protection against EMI.
What is Shielded Twisted Pair?
A technology that allows a single cable to provide both data and electrical power to devices such as wireless access points, IP cameras, and VoIP phones.
What is Power over Ethernet (PoE)?
A unique identifier burned into the ROM of every Ethernet NIC. The first half of the address (the first six digits) is assigned to each manufacturer. The manufacturer determines the rest of the address, assigning a unique value that identifies the host address.
What is Media Access Control (MAC) Address?
The central connecting point of a physical star. It uses a logical bus topology.
Two twisted wires that carry the data signals (one conductor carries a positive signal; one carries a negative signal). Twisting the cables reduces the effects of electromagnetic interference (EMI) and crosstalk.
What is Unshielded Twisted Pair (UTP)?
A two-lead semiconductor light source that emits visible light when an electric current passes through it.
What is a Light-emitting diode (LED)?
These permit circuits to be arranged and rearranged by plugging and unplugging respective patch cords on a mounted hardware assembly.
What is a patch panel?
Hosts use this to discover the MAC address of a device from its IP address.
What is Address Resolution Protocol (ARP)?
A device that connects two (or more) media segments on the same subnet. It filters traffic between both segments based on the MAC address in the frame.
What is a Bridge?
The loss of signal strength from one end of a cable to the other. This is also known as dB loss.
What is Attenuation?
The line that marks the boundary between the telecommunications (telco) equipment and your private network or telephone system.
What is Demarcation point (demarc)?
When connecting two devices using twisted-pair cabling, this determines which wire goes to which pin of the connector.
What is Pinout?
Hosts use this to find the IP address of a host with a known MAC address.
What is Reverse Address Resolution Protocol (RARP)?
A multi-port bridge that performs filtering based on MAC addresses and provides additional features not found in a bridge.
What is a Switch?
A part of a building that provides a pathway for the airflow needed by heating and air conditioning systems, such as above a dropped ceiling or below a raised floor.
What is a Plenum Space?
An area that connects multiple floors where cables can be run. This area cannot be a plenum space.
What is a Riser Space?
In the United States, a term used for a public telephone company that provides local services. Sometimes called telcos.
What is Local Exchange Carrier (LEC)?
Similar to a GBIC but is smaller in size. Sometimes called a mini-GBIC.
What is Small form-factor pluggable (SFP)?
A device that connects two or more network segments or subnets.
What is a Router?
This joins several light wavelengths (colors) onto a single strand of fiber by using different wavelengths of laser light.
What is Wavelength Division Multiplexing (WDM)?
A frame or rack that is used to interconnect and manage telecommunication wiring in a building. It functions like an old-time telephone switchboard, where operators used connecting wires to route telephone calls. Can also refer to the room that houses the traditional kind along with networking patch panels.
What is Main Distribution Frame (MDF)?
In fiber optic and Ethernet systems, a transceiver that converts electrical signals to optical signals and vice versa.
What is a Gigabit Interface Converter (GBIC)?
(a quad, or 4-channel, small form-factor pluggable) A compact hot-pluggable transceiver that is also used for data communication applications.
What is QSFP?
A switch that is capable of reading Layer 3 (network) addresses and routing packets between subnets.
What is a Layer 3 Switch?