Electronic Manufacturing Services (EMS)

Electronic Manufacturing Services (EMS) or Electronic Contract Manufacturing (ECM) are terms used for companies that design, manufacture, test, distribute, and provide return/repair services for electronic components and assemblies for original equipment manufacturers (OEMs).

London Metal Exchange (LME)

The LME offers worldwide reference pricing for metals such as aluminum, copper, tin, nickel, zinc, lead, gold, etc.

Single Mode

Single Mode optical fiber is designed to carry only a single ray of light; this produces more of a direct line. Ideal for long distances.

Multi-Mode

Multi-Mode optical fiber is designed to carry multiple rays of light, because of it's larger core size. Ideal for short distances.

Twisted Pairs

A Twisted Pair are two wires twists together in a spiral format, which helps reduce Electromagnetic Interference (EMI).

Electromagnetic Interference (EMI)

Electromagnetic Interference (EMI) is caused by outside disturbances that interrupt, obstruct, or limit the effectiveness of the cables performance.

Unshielded Twisted Pairs (UTP)

Unshielded Twisted Pairs has no metal shielding of any kind, UTPs only protection from EMI is its internal structure with its twisted pairs.

Foiled Twisted Pairs (FTP)

Foiled Twisted Pairs has foiled shielding surrounds all four pairs.

Shielded Twisted Pairs (STP)

Shielded Twisted Pairs has each individual pair wrapped in their own personal shield.

Shielded Foiled Twisted Pairs (SFTP of S/STP)

Shielded Foiled Twisted Pairs has foiled shielding surrounds all four pairs and each individual pair is wrapped in their own personal shield.

Frequency

The number of times a periodic action occurs in one second. Measured in Hertz.

Dielectric

The insulating material that separated the center conductor and the shielding.

American Wire Gauge (AWG)

A U.S. standard set of non-ferrous wire conductor sizes. Typical data wiring is AWG number 24, 26 or 28. The higher the gauge number, the smaller the diameter and the thinner the wire.

Bandwidth

The amount of data transmitted per unit of time, typically bits per second (b/s) or bytes per second (B/s).

Full-duplex

Computer data transmission occuring in both directions simultaneously.

Full-speed

USB operation at 12 Mb/s.

High-speed

USB operation at 480 Mb/s.

Low-speed

USB operation at 1.5 Mb/s.

Analog Signals

Both video and audio signals that are continuously varying in level are said to be analog.

Attenuation

A reduction in the strength of a signal.

Pixel

A Pixel is single point on a display.

Resolution

The Resolution is the density of pixels in a given area typically expressed as the horizontal x vertical values, (ex. 640x480).

Backshell (Hood)

A mechanical backing that is sometimes put onto a connector. The device protects the conductors and can be assembled or injection molded. Commonly used with D-Sub connectors.

Cable

A set of insulated wires or conductors within a extruded jacket. Many types of cable utilize shielding around the wires and under the cable jacket.

Cable Assembly

A cable that has been terminated with one or more connectors.

Conductor

A metal path (usually copper) that passes electricity. When discussing data cabling, "wire" and "conductor" are synonymous.

Crimping

A means of securing an electrical contact to a wire using tools that compress the metal contact around the wire.

Crosstalk

Crosstalk is when unwanted electromagnetic fields from conductors are transferred into adjacent conductors. Crosstalk is contolled by separating or shielding conductors or twisting into a pair.

Ground Wire (Drain Wire)

A Ground Wire is an extra conductor (usually a bare wire) added to a cable for connection of the grounding path.

Injection Molding

The process used to inject molten polymer into a mold. Connector backshells are often injection molded.

Insulation

A material with a very high resistivity used to protect conductors. Insulation is usually extruded over the wire or conductor after the drawing process.

Soldering

A means of securing an electrical contact to a wire by heating a low alloy of tin and lead also known as "solder".

802.11a

An IEEE standard for wireless Ethernet networking that operates in the 5 GHz radio band (ISM frequency band) and uses the IP protocol. Maximum transmission speed is 54Mbps and approximate wireless range is 25-75 feet indoors.

802.11b

An IEEE standard for wireless Ethernet networking that operates in the 2.4 GHz radio band (ISM frequency band) and uses the IP protocol. Maximum transmission speed is 11Mbps and approximate wireless range is 100-200 feet indoors.

802/11g

An IEEE standard for wireless Ethernet networking that operates in the 2.4 GHz radio band (ISM frequency band) and uses the IP protocol. Maximum transmission speed is 54Mbps and approximate wireless range is 100-200 feet indoors.

Bubble Boot

Slimline Boot

Insertion Loss

Return Loss

Polyvinyl Vinyl Chloride (PVC)

Polyvinyl Vinyl Chloride is a general-purpose plastic jacket material used for cables. Low in cost, flexible, and widely used as a cable jacket for many applications - computers, communications, low-voltage wiring, etc. In the cable world, "PVC" is often used to denote a cable that is not suitable for use in a plenum airspace. PVC can potentially be dangerous in a fire situation, releasing heavy smoke and hydrogen chloride gas, which can be irritating to humans and corrosive to electronic devices. PVC cables often have a CM, CMG, or CMR rating as defined by the National Electrical Code (NEC).

CMR (Riser)

Cable that is suitable for use in a riser application. In commercial buildings, a riser is the space used by vertical telecommunications infrastructure, connecting from one floor to another. CMR indicated cable intended for use within building in vertical shafts inaccordance with Section 800.53(B) of the NEC. The test used for CMR cables is defined in the UL 1666 standard, which limits flame propagation height.

CMP (Plenum)

"Plenum" cables are built with a jacket made of materials that give off low amounts of smoke and which retard the spread of flames. The word "plenum" refers to an airspace used for air cirulation by a HVAC system, such as a drop ceiling or a raised floor. One popular jacket material is FEP (fluorinated ethylenepropylene), which is softer, more pliable version of Teflon (also known as PTFE - polytetrafluoroethylene). Even though "plenum cables" are usually identified as separate from "PVC cables", PVC compounds are often used in the construction of plenum jacket material. CMP is a classification of cables defined by the NEC for cables designed to be instanlled into a building's plenum airspaces. The most popular test for CMP cables is defined by the NFPA 262 standard, which outlines criteria for both low-smoke abd flame-travel performance.

Patch Cord

A Patch Cord is considered an cable assembly wth modular plugs on each end and can be both Copper & Glass Fiber Optics. Used for patching equipment to the patch panel in the equipment room and also used to connect to phones and computer at the drop.

Gaphics Display Resolution (GDR)

The Graphics Display Resolution (GDR) describes the width and height dimensions of a display, such as a computer monitor and television in pixels (ex. 480p).

1000Base-T

One of the more common types of Ethernet Local Area Networking (LAN) cabling. Specifies 1000 Mbps (baseband) carried over twisted pair. Also known as Gigabit Ethernet or GigE.

100Base-T

One of the more common types of Ethernet Local Area Networking (LAN) cabling. Specifies 100 Mbps (baseband) carried over twisted pair. Also known as Fast Ethernet.

10Base-T

One of the more common types of Ethernet Local Area Networking (LAN) cabling. Specifies 10 Mbps (baseband) carried over twisted pair.

ARCnet

A network developed by DataPoint. Originally proprietary, by the late 1980s it was no longer proprietary and had about as large a market share as Ethernet among small businesses. It was almost as fast and was considerably cheaper at the time.

BNC

A connector for coaxial cable such as that used for some video connections and RG58 "cheapernet" connections. A BNC connector has a bayonet-type shell with two small knobs on the female connector which lock into spiral slots in the male connector when it is twisted on. Different sources expand BNC as Bayonet Navy Connector, British Naval Connector, Bayonet Neill Concelman, or Bayonet Nut Connection.

Daisy chain

A bus wiring scheme in which, for example, device A is wired to device B, device B is wired to device C, etc. The last device is normally wired to a resistor or terminator. All devices may receive identical signals or, in contrast to a simple bus, each device in the chain may modify one or more signals before passing them on.

DIN

The German standardization connector type body, also a member of ISO.

Ethernet

A local-area network (LAN) architecture developed by Xerox Corporation in cooperation with DEC and Intel in 1976. Ethernet uses a bus or star topology and supports data transfer rates of 10 Mbps. The Ethernet specification served as the basis for the IEEE 802.3 standard, which specifies the physical and lower software layers. Ethernet uses the CSMA/CD access method to handle simultaneous demands. It is one of the most widely implemented LAN standards. A newer version of Ethernet, called 100Base-T (or Fast Ethernet), supports data transfer rates of 100 Mbps. And the newest version, Gigabit Ethernet supports data rates of 1 gigabit (1,000 megabits) per second.

Ethernet IP

Ethernet/IP (Ethernet Industrial Protocol) is a network communication standard capable of handling large amounts of data at speeds of 10 Mbps or 100 Mbps, and at up to 1500 bytes per packet. The specification uses an open protocol at the Application layer. It is especially popular for control applications.

Ethernet Protocols

802.3 is a standard specification for Ethernet, a method of physical communication in a local area network (LAN), which is maintained by the Institute of Electrical and Electronics Engineers (IEEE).

Fiber Node

A point of interface between a fiber trunk and the coaxial distribution.

Fiber Optics

(1) Very thin and pliable tubes of glass or plastic used to carry wide bands of frequencies. (2) Transmission medium that uses glass or plastic fibers vs. other, copper-based wires to transmit data or voice signals. Fiber-optic cable offers much greater capacity and transmission speeds than traditional mediums.

Gateway

A node on a network that serves as an entrance to another network. In enterprises, the gateway is the computer that routes the traffic from a workstation to the outside network that is serving the Web pages. In homes, the gateway is the ISP that connects the user to the internet. In enterprises, the gateway node often acts as a proxy server and a firewall. The gateway is also associated with both a router, which use headers and forwarding tables to determine where packets are sent, and a switch, which provides the actual path for the packet in and out of the gateway.

Hub

A common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

IEEE-1394

An electronics standard for connecting devices to a personal computer or set-top box. IEEE-1394 provides a single plug-and-socket connection on which up to 63 devices can be attached with data transfer speeds up to 400 Mbps (megabits per second). The standard describes a serial bus or pathway between one or more peripheral devices and a host's microprocessor. Also known as Firewire or i.Link.

Impedance

Resistance to alternating-current flow.

I/O

Short for input/output. The term I/O is used to describe any program, operation or device that transfers data to or from a computer and to or from a peripheral device. Every transfer is an output from one device and an input into another. Devices such as keyboards and mouses are input-only devices while devices such as printers are output-only. A writable CD-ROM is both an input and an output device.

Jumper

A removable wire or small plug whose presence or absence is used to determine some aspect of hardware configuration.

Kilo (K)

Meaning one thousand. Communications and computer terminology, however, uses the term K or Kilo differently. In communications terminology, one K is equal to 1000, but when measuring computer memory or disk space, one K is equal to 1024.

KiloBits Per Second (Kbps)

One Kbps is equal to 1000 bits transmitted in one second.

Local Area Network (LAN)

A LAN is a collection of computing equipment at a single location (e.g., an office building or campus) that communicate with each other to share resources and information, such as disk storage and files, printers, and e-mail. See also WAN. Or a non-public data network in which serial transmission is used for direct data communication among data stations located on the user's premises.

Low Smoke Zero Halogen (LSZH)

Low Smoke Zero Halogen cables are built with a jacket material free from halogenic materials (such as chlorine and fluorine), because of the toxic nature of these chemicals when burned. However, LSZH cables have not been specified by the NEC for use in installations in the U.S, and they may have questionable flammability characteristics. cable reduces the amount of toxic and corrosive gas emitted during combustion. LSZH cable produces less smoke and releases little or no halogen gas when burned.

MegaHertz (MHz)

One million cycles per second.

Network

Hardware and software data communication systems. The ISO seven layer model attempts to provide a way of partitioning any computer network into independent modules from the lowest (physical) layer to the highest (application) layer. Many different specifications exist at each of these layers. Networks are often also classified according to their geographical extent: local area network (LAN), metropolitan area network (MAN), wide area network (WAN) and also according to the protocols used.

Null modem

A cable, especially an RS-232 cable, for connecting serial ports on two computers directly, rather than via modems. Since, according to the specification, both computers should transmit on pin three of their RS-232 connectors and receive on pin two, a null modem cable needs to connect one computer's pin two to the other's pin three and vice versa. It also needs to have male connectors at both ends (again, according to the specification).

Ohm

The standard unit of resistance, reactance and impedance. A resistant of 1 ohm will conduct 1 ampere of current when a voltage of 1 volt is placed across it.

Optical Fiber

An extremely thin, flexible thread of pure glass, able to carry one thousand times the information possible with traditional copper wire.

Pin-out

(Or "pinout") The allocation of logical functions or signals to the electrical connection points (pins) of an integrated circuit or other component or connector.

Protocol

A standard way of communicating across a network. A protocol is the "language" of the network. A method by which two dissimilar systems can communicate. TCP is a protocol which runs over a network.

Proxy Server

A server that sits between a client application, such as a Web browser, and a real server. It intercepts all requests to the real server to see if it can fulfill the requests itself. If not, it forwards the request to the real server.

RS-232

In telecommunications, RS-232 (Recommended Standard 232) is a standard for serial binary data signals connecting between a DTE (Data terminal equipment) and a DCE (Data Circuit-terminating Equipment). It is commonly used in computer serial ports. A similar ITU-T standard is V.24.

RS-530

RS-530 is a high speed 25-position interface for Data Terminal Equipment (DTE) and Data Circuit-Terminating Equipment (DCE).

Serial port

(Or "com port") A connector on a computer to which you can attach a serial line connected to peripherals which communicate using a serial (bit-stream) protocol. The most common type of serial port is a 25-pin D-type connector carrying RS-232 signals. Smaller connectors (e.g. 9-pin D-type) carrying a subset of RS-232 are often used on personal computers. The serial port is usually connected to an integrated circuit called a UART which handles the conversion between serial and parallel data.

T-1 Line

A leased-line connection capable of carrying data at 1,544,000 bits per second, or 1.544 Mbps. Generally, a T-1 line will move a megabyte of data in under 10 seconds. That is still not fast enough for full-screen, full-motion video, for which you need at least 10,000,000 bits per second. T-1 is the fastest speed commonly used to connect networks to the Internet.

T-3 Line

A leased-line connection capable of carrying data at 45,000,000 bits per second, or 45 Mbps. This is more than enough to do full-screen, full-motion video.

TCP/IP

Stands for "Transmission Control Protocol / Internet Protocol" - TCP/IP is a suite of communications protocols that forms the basis for and defines the Internet.

Token ring

A computer local area network arbitration scheme in which conflicts in the transmission of messages are avoided by the granting of "tokens" which give permission to send. A station keeps the token while transmitting a message, if it has a message to transmit, and then passes it on to the next station. Often, "Token Ring" is used to refer to the IEEE 802.5 token ring standard, which is the most common type of token ring.

Universal Serial Bus (USB)

A plug-n-play standard for connecting multiple (up to 127) input/output devices to a single high-bandwidth port. The design of the bus allows hot-swapping of the devices (disconnection and reconnection without powering the computer off) and automatic configuration. The USB peripheral bus standard was developed by Compaq, IBM, DEC, Intel, Microsoft, NEC, and Northern Telecom. The original version of USB (USB1.1) supports a data rate of 12Mbps, while the second version (USB2.0) supports a data rate of 480 Mbps.

Wide Area Network (WAN)

A computer network which usually spans larger geographic area, such as cities, counties, states, nations and planets. WAN's usually employ telephone-type topologies, like T1, T2, T5, ATM, etc. The Internet is a WAN which is held together by LANs, which network computers.