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|Glossary of terms used in Connectivity|
Shielded Twisted Pair.
Un-Shielded Twisted Pair.
For a cable to be considered coaxial it must contain a center core conductor, and a second conductor wrapped around it. The second conductor can be made from different types of braided conductors (typically au - gold, cu - copper, and al - aluminum) or a metal foil. This outer wire is typically the ground.
RG 62 -
A 93 ohm coaxial cable.
RG 6 -
A 75 ohm coaxial cable used with Cable TV, Satellite and High Definition TV. It is also becoming the minimal standard for home installations due to it's full frequency capacity.
RG 6 - Quad Shield
A 75 ohm coaxial cable used with Cable TV, Satellite and High Definition TV. It is also becoming the minimal standard for home installations due to it's full frequency capacity. This cable is quad shielded which will help prevent line interference and noise.
RG 59 -
A 75 ohm coaxial cable used with Cable TV. It is the old standard for home installations, now installers are using the new RG6 cable.
RG 58 -
A 50 ohm coaxial cable used with Cable TV and BNC environments.
RS-232 is a serial connection used with computers, data terminals (printer) and modems. An RS-232 connection is good to about 50 ft at a 20Kbps transmission speed, using a 25 pin (DB25) cable. Just about every parallel printer on the market will connect to the PC through the RS-232 (DB25) port.
A standard method used to measure wire. The numbering system works backwards from what people would think, the thicker (heavier) the wire, the lower the number. For example: a 24AWG wire is thicker / heavier than a 26AWG wire.
The range of frequencies used to describe the potential capacity of the device or system. The numerical value is expressed in Hz (Hertz) or Megahertz (MHz) and used for both copper and fiber.
This cable has a maximum frequency range of 16 MHz. It is typically used with voice and low speed networks.
This cable is used for networks and mulit-line phone systems. It has a maximum frequency of 100 MHz and can transmits up to 10/100Mbps. Category 5 (CAT-5) was defined in ANSI/TIA/EIA 568A, but it not used with ANSI/TIA/EIA 568B.
CAT-5 E -
This cable is used for networks and mulit-line phone systems. It has a maximum frequency of 350 MHz and can transmits up to 10/100/1000Mbps. Category 5 Enhanced (CAT-5 E) will work with ANSI/TIA/EIA 568A and ANSI/TIA/EIA 568B. It is the current standard for installing networks.
This cable is used for networks and mulit-line phone systems. It has a maximum frequency of 500 MHz and can transmits up to 10/100/1000Mbps.
A DB9 (RS-488) connector is a 9 pin serial connection used on most laptop and desktop computers, as well as token ring connections. DB connectors are gender specific (Male / Female), so when ordering or connecting any DB connector, make sure you have the correct gender on the cable.
A gender specific connector (Male / Female) with 15 pins (DB15) used for connecting to Mac Monitors or PC Joysticks. When ordering or connecting any DB connector, make sure you have the correct gender on the cable.
HD15 (VGA) -
A gender specific connector (Male / Female) with 15 pins (HD15 / VGA) used for connecting PC's to PC Monitors. When ordering or connecting an HD connector, make sure you have the correct gender on the cable.
A DB25 (RS-232) connector is a 25 pin connection used on most desktop computers to connect serial or parallel ports together. DB connectors are gender specific (Male / Female), so when ordering or connecting any DB connector, make sure you have the correct gender on the cable.
In data communications, duplex defines the direction of the transmission. Duplex transmissions are bi-directional as opposed. Duplex are able to transmit in both directions, however, only one at a time, this is known as half duplex. A full duplex transmission can send and receive information at the same time.
Drain Wire -
An uninsulated wire inside a shielded cable that runs the length of the cable and acts as a grounding point for the shield.
is available as a plug (male) connector only, and mates with a DVI-I receptacle. DVI-A mates to the analog-only pins of the DVI-I connector. This connector is used in adapters, where there is the need to convert to or from a traditional analog VGA signal.
DVI-D - is a digital ONLY connector, and is the leading connector standard for digital only connection. Was the orginal connector used for HDTV but is being rapidly repaced by HDMI. DVI-D is still found on first generation HDTV products and Computer products designed to work with home video products.
DVI-I - Single link and Dual link -
can support digital and analog (VGA). The connector has a few more pins, and some display and graphics cards manufacturers are offering this connector type on their products, as opposed to separate analog and digital connectors. Be careful! Some manufacturers are not supporting analog connections, even though they are using a DVI-I receptacle!
Ethernet works as a broadcast network where when one station transmits a message, all stations will "hear" the message, but only the addressed station will "open" the message. Ethernet has become a standard for LANs and has gone from 10Mbps to 1000Mbps over the last 20 years.
F-Connectors are used on coaxial cable, typically used with in Cable TV, VCR's, Security Systems, Satelitte Systems and other Video applications. The most common cables used are RG58, RG59 and RG6. The connectors come either in a single or 2 piece piece set. They can either be crimped, soldered, or twisted on.
A thin strand of glass or plastic optical fiber that transmits light impulses.
The number of cycles or waves per second, expressed in Hertz, (Hz). In structured cabling the information carrying capacity (bandwidth) is measured in Hz.
Full Duplex -
A signal or transmission where the transfer of data can go in both directions at the same time. Full duplex signals allow more information to be transfered.
Gender Changer -
A small adapter that changes the gender of a connector. The adapter will have the same gender on both sides. For example: If you have a female ended cable that needs to connect to a female device you will use a Male Gender Changer to convert/couple the two female connections
A transmission speed of 1 billion bits of information. Transmission speeds are measured in bits per second, therefore a gigabit is 1 billion bits of information per second. More commonly known as Gigbit or 1000Mbps.
Half Duplex -
A signal or transmission where the transfer of data can go in both directions, however, it can only be sent in one direction at a time.
Hertz (Hz) -
A unit used in the measurement of frequency equal to one cycle per second. Frequency is generally measured in Kilohertz (KHz) or Megahertz (Mhz).
The standard today for Home Theater. HDMI (High Definition Multimedia Interface) carries the same digital signals as DVI, but with the addition of digital audio and control signals. This makes HDMI ideal for consumer video devices, such as DVD players and HD televisions. Although the HDMI signal is backwards compatible with DVI, an HDMI to HDMI connection is designed to travel a much further distance than DVI.
A network device that is used as a central location in a wired LAN. The hub controls, manages and directs information through that segment of the network connected through that hub.
IEEE is short for Institute of Electrical and Electronics Engineers (typically pronounced I triple E). This group has set most of the LAN standards through the 802 series.
A measure of the total opposition to current flow in an alternating current circuit, made up of two components. With higher speed and bandwidth networks, the impedance of the cable plant as a whole can affect the networks performance.
Impact Tool -
Impact Tools have a spring loaded head that when used will punch down the on the conductor and into the block. If you're setting up a phone or network system you may need to use an impact tool to wire up the large patch panels. Typical blades that are used in impact tools are 66, 88, and 110.
A measurement referring to 1000 as in kilometer (1000 meters), kilohertz (1000 hertz), kilobit (1000bits) etc. There are other forms of measurements such as mega (1,000,000) and giga which is one billion.
The amount of delay a signal has when going through a network or a part of a network. The Total Latency is calculated by adding together all the time delays through each device and media.
M1 - M1DA - M1D - P&D / EVC -
P&D, M1 or EVC, is another connector type that some manufacturers, are using on their projectors. This connector looks a lot like the DVI-I connector, but is slightly larger in size. Like DVI-I, it also handles analog and digital. Unlike the other standards, it has the flexibility to also handle USB and FireWire video connections. Check with your display or graphics card manufacturer for compatible signals.
MAC Address -
Every computer has its own unique address that is obtained via the Network Interface Card. Therefore a computer without a NIC card does not have an address. The IEEE assigns each address and prevents duplicate addresses from happening.
A prefix denoting 1,000,000 (1 million). In data communications this term is used in describing the speed of data transfer in megabits per second, the bandwidth of a given system in megahertz.
Megabit Per Second (Mbps) -
A measurement of the transmission speed of a piece of equipment or network equal to 1 million bits per second.
Megabyte (MB) -
Megabytes is typically how the hard drive memory of computers are measured. Since hard drives are becoming so large in size, gigabyte's (GB) are used to measure them.
Megahertz (MHz) -
A unit of frequency measurement equal to 1 million Hz or cycles per second. Megahertz is one measurement of bandwidth, or information carrying capacity of a network, cable or connectors. Generally, Hz should not be confused with Bps (bits per second).
MTRJ Connector -
MTRJ is the newer type of small fiber optic connector.
The combining of two or more signals onto one communications channel. By doing so the amount of data thoughput on each channel is increased. A multiplexed signal must be demultiplexed at the receiver end in order to complete the transmission.
The process of separating once combined signals back into the original individual signals for processing.
Network Interface Card NIC -
The network interface card is the point where the computer is connected to the local area network. The NIC is matched to the type and speed of the network, eg: 10/100Mbps Ethernet.
A random and/or persistent induction of unwanted electrical or radio frequency signals onto a cable which interferes with and/or degrades the quality of the signal.
A unit of resistance. The measurement of the opposition to the flow of direct current is resistance. One volt will cause 1 ampere to flow through 1 ohm of resistance.
Ohms Law -
The mathematical relationship between ohms(R), volts(V) and Amps(I). Technically is states that current (I) is directly proportionate to voltage and inversely proportionate to resistance. The mathematical equations are: V = I x R or I = V/R or R = V/I or
In some buildings, the entire space above the drop ceiling is used as a return air pathway instead of a set of ducts. Therefore air circulated within that space gets distributed throughout the floor, or the building. If a cable located in an open air plenum has a PVC jacket and catches fire, the toxic fumes would spread throughout the entire floor via the open plenum, thereby suffocating or at least impairing people's ability to get out of the building. To overcome this, some cables are coated with Teflon to prevent the spread of flame and toxic fumes. Individual states and provinces regulate what types of cables are acceptable as a minimum standard. Extreme care must be taken by the installer and designer to ensure the proper cables are specified and installed
Plenum Cable -
Plenum rated cable has been specifically engineered to be placed in the plenum air space above a suspended ceiling. In the event of a fire, the components of the jacket and conductor insulation will not give off toxic fumes and are slower to burn. A plenum rated cable will have on it one or both of the following markings: FT-6 or CMP. Both of these markings are recognized in the United States and Canada.
Polyvinylchloride PVC -
A thermoplastic flame and water retardant material commonly used in the construction of communications and other building cables. Although flame retardant, PVC gives off toxic fumes when burned. For this reason many codes do not allow PVC based cables to be installed in return air plenums or ducts in case of fire, instead Plenum rated cable is used.
The standard which governs the installation of cabling and components in a commercial building. The full name is ANSI/TIA/EIA 568B, although it more commonly goes by 568B.
The standards document published by the TIA governing the design and installation of pathways and spaces for cable used in those pathways and spaces as they relate commercial buildings. The full name is ANSI/TIA/EIA 568A, although it more commonly goes by 569A.
Twisted Pair Cable -
A cable consisting of individual conductors twisted in pairs around each other. The purpose of twisting the conductors around each other is to reduce the affects of crosstalk.
The distance between a point on one wave to the similar point on the next wave. The number of times this happens over a given period of time (normally 1 second) is the frequency. Frequency is measured in Hertz.
SC Connector -
A type of fiber optic connector that uses a push to snap on / push to snap off connector. The SC connector can be used with both multimode and singlemode fiber.
ST Connector -
A fiber optic connector that uses twist-on / twist-off.