Basic Cable Types | CompTIA A+ 220-1001 | 3.1

In this video you will learn about basic cable types, features, & their purposes such as:  network cables, video cables, multipurpose cables, peripheral cables, hard drive cables, and adapters.

Network Cables

Network cabling are networking hardware used to connect one network device to other network devices or to connect two or more computers to share printers, scanners, etc. Different types of network cables, such as coaxial cable, optical fiber cable, and twisted pair cables, are used depending on the network’s physical layer, topology, and size. The devices can be separated by a few meters or nearly unlimited distances.

Ethernet

Most of the networking cables covered in this lesson are different types of Ethernet cables. Ethernet is a system of communication rules that allow computers to work together. Ethernet is considered a networking protocol, which is slightly different than that of an application protocol. Ethernet describes how network devices can format and transmit data so other devices on the same local or campus area network segment can recognize, receive and process information (wired or wirelessly). An Ethernet cable is the physical, encased wiring over which the data travels. Ethernet cables carry small voltage pulses (1 is voltage, 0 is no voltage) over a single frequency.  This is known as baseband transmission.  It is bidirectional, which means hosts can send and receive data on one cable.  The various capabilities are indicated in cable categories.

CAT5e, CAT6, and CAT6a

The most common standard cabling grades are: Category 5e (CAT5e), Category 6 (CAT6), and Category 6a (CAT6a). All are suitable for use with both standard 10BASE-T & Fast Ethernet networking. CAT6, CAT6a, & CAT7 are capable of supporting 10BASE-T (10GB) Ethernet networks. Regardless of category & speed, all copper Ethernet cables have a distance limitation of about 100m (approx. 300ft) before the data signal weakens and another device such as a switch, hub or a repeater has to be introduced to boost the signal.

Categories & Uses for TP Cabling

Plenum and PVC

There are two categories of TP cable in terms of fire rating:

  • Standard:  Suitable for patch cables between a NIC and a network jack or in a patch panel.  Typically has a PVC jacket, which can create a lot of smoke when burned.
  • Plenum:  Designed for use in plenum space which is a part of a building that can facilitate air circulation for heating & cooling (ventilator shafts, under floors, or between suspended ceilings and the permanent ceilings).  Plenum cables produce less smoke & lower levels of toxic chemicals when burned, and is commonly self-extinguishing.  Plenum cable jackets might be made from Teflon or from a modified version of PVC that produces less smoke when burned than standard PVC.

Shielded Twisted Pair (STP) vs. Unshielded Twisted Pair (UTP)

Twisted pair (TP) cabling is a type of wiring in which two conductors of a single circuit are twisted together for the purposes of improving electromagnetic compatibility. TP cabling is the most common of the major cabling types. TP cabling typically consists of four twisted pairs of wires surrounded by a flexible jacket (unshielded TP, or UTP) or various types of metal foil or braid (shielded TP, or STP). STP & UTP use the same RJ-45 connector but STP includes a metal shield for electrical insulation between the wire pairs & the outer jacket. STP is also stiffer & more durable, yet more expensive & harder to loop through tight spaces than UTP. It is used where electromagnetic interference (EMI) prevents the use of UTP cable. Both cables can be purchased in prebuilt assemblies or can be built using bulk cable & connectors.

STP cable includes a metal shield while a UTP cable does not.

T568B (EIA-568B) and T568A (EIA-568A) Standards

The wiring standard for all types of Ethernet UTP cables is known as T568B (EIA-568B).  This type of cable is also known as a straight-through cable which is most commonly used to connect a host to a client, such as the RJ-45 wire connected from a PC to a home router (dissimilar devices). The wire order, from left to right when looking at the top of the connector is:

  1. Pin 1:  orange/white stripe
  2. Pin 2:  orange
  3. Pin 3:  green/white stripe
  4. Pin 4:  blue
  5. Pin 5:  blue/white stripe
  6. Pin 6:  green
  7. Pin 7:  brown/white stripe
  8. Pin 8:  brown

The T568A (EIA-568A) standard swaps the positions of the orange and green wires used in T568B.  This type of cable is also known as a crossover cable which are most commonly used to connect two hosts directly, such as a PC directly connecting to another PC, or a switch connecting to another switch (similar devices). The wire order, from left to right when looking at the top of the connector is:

  1. Pin 1:  green/white stripe
  2. Pin 2:  green
  3. Pin 3:  orange/white stripe
  4. Pin 4:  blue
  5. Pin 5:  blue/white stripe
  6. Pin 6:  orange
  7. Pin 7:  brown/white stripe
  8. Pin 8:  brown

You can create a crossover cable by building one end to the T568B standard and the other end to the T568A standard.

RJ-45 Pinout

Fiber

Fiber optics is a technology that uses glass (or plastic) threads (fibers) to transmit data.  A fiber optic cable consists of a bundle of glass threads, each of which is capable of transmitting messages modulated onto light waves.  Fiber optics is the fastest type of internet service which is primarily used as a backbone between networks. Fiber optic cable comes in two major types:

  • Single-mode:  Has a thin core (between 8 & 10 microns) designed to carry a single light ray long distances (up to 60km or further).  Single-mode cable uses a laser diode as a light source. Typical uses include cable TV and telephone companies.
  • Multi-mode:  Has a thicker core (62.5 microns) than single-mode cable; carries multiple light rays for short distances (up to 10km).  Multi-mode cable uses an LED light source. Typical uses include local and metropolitan area networks (LANs & MANs).

Fiber optic devices and cables use one of several connector types:

  • SC:  uses square connectors
  • LC:  uses square connectors
  • ST:  uses round connectors
Fiber Optic Cable Connectors

RG-6 & RG-59 Coaxial

Coaxial cabling is the oldest type of network cabling; its data wires are surrounded by a wire mesh for insulation.  Prior to the advent of fiber optics, the fastest internet service available to home and business customers was cable internet.  Cable internet is a form of broadband internet access which uses the same RG-6 coaxial cable as a cable television, but adds a device called a cable modem to convert the signal for use by computers and home/business networks. RG-6 has a 75-ohm resistance, uses an 18-gauge center conductor, is available in quad-shielded versions, & can carry signals up to 1.5GHz, making it much better for HDTV signals.

RG-59 is used in older cable TV or satellite TV installations as well as in CCTV security installations; 75-ohm resistance.  RG-59 uses a 22-gauge center conductor and a single outer shield.  It is designed for signals up to 50MHz.

RG6 Coaxial Cable

The BNC connector (Bayonet-Neill-Concelman) is a miniature quick connect/disconnect radio frequency connector used for coaxial cable. BNC connectors are typically used for CCTV cameras & some types of video projectors. BNC connectors are crimped to the coaxial cable and use a positive-locking bayonet mount.

BNC Connector

The F connector is a coaxial radio frequency connector used for “over the air” terrestrial television, cable television and universally for satellite television and cable modems. F connectors can be crimped or attached via compression to the coaxial cable. High quality cables use a threaded connector.

F Connector

A coax signal splitter (a two-way splitter) takes the power on the input port and splits it equally among the output ports. For example, a 2-way splitter has one input port and two output ports. It sends half the power of the input signal to one of the output ports. The other half is sent to the other output port.

Two-Way Splitter

Video Cables

With the selection of a monitor or projector for use with a particular video card or integrated video port, it’s helpful to understand the physical and feature differences between different video connector types, such as VGA, DVI, HDMI, DisplayPort component/RGB, BNC, S-video, and composite.

Video Connector Types Overview

VGA

A video graphics array connector is a standard connector used for computer analog video output. A VGA card made for use with a standard analog monitor uses a DB15F 15-pin female connector, which plugs into the DB15M male connector used by the VGA cable from the monitor. By varying the levels of red, green, or blue per dot (pixel) onscreen, a VGA port and monitor can display an unlimited number of colors, but practical color limits are based on the video card’s memory and the desired screen resolution. The base resolution (horizontal x vertical dots) of VGA is 640×480.  An enhanced version of VGA is Super VGA, or SVGA, which typically refers to 800×600 VGA resolution.

VGA Connector

HDMI

High-definition multimedia interface is a connector and cable capable of transmitting high-quality and high-bandwidth streams of audio and video between devices.  HDMI was originally developed for use with HDTVs, it is now a common feature on laptops, desktops, & monitors as well as HDTVs and HD projectors.  HDMI is available in various versions, but older HDMI cables might not support advanced functions such as 3D or resolutions beyond 1080p.

The most recent HDMI standard, version 2.1, supports video resolutions and refresh rates including 8K60 and 4K120, as well as resolutions up to 10K.  The earlier version, version 1.4b, supports 1080p HDTV and resolutions up to 4096×2160 (also known as 4K x 2K), 48-bit color depths, various types of uncompressed and compressed digital audio, 3D over HDMI, and Fast Ethernet.  The most common HDMI port is Type A, which has 19 pins.  It is used to achieve high-definition resolutions such as 1920×1080 (known as 1080p or 1080i).

HDMI

Mini-HDMI

The HDMI 1.3 and later specifications also define a mini-HDMI connector (Type C).  It is smaller than the Type A plug but has the same 19-pin configuration.  The HDMI 1.4 specification defines a micro-HDMI connector (Type D), which uses the same 19-pin configuration but in a connector the size of a micro-USB plug.

Various HDMI Cables

DisplayPort

DisplayPort is a digital display interface primarily used to connect to a video source to a display device such as a computer monitor.  It can also be used to carry audio, USB and other forms of data. DisplayPort has similar resolution and audio/video features of HDMI, but with 2 major differences:

  • DisplayPort is a royalty-free video standard
  • DisplayPort 1.2 and later support daisy-chaining of displays

DisplayPort utilizes packet transmission similar to Ethernet and USB.  Each packet transmitted has the clock embedded (whereas DVI and HDMI utilize a separate clocking signal). DisplayPort connectors are not compatible with USB, DVI, or HDMI; however, devices that support dual-mode DisplayPort (DisplayPort++) technology are capable of sending HDMI or DVI signals with the use of the appropriate adapter.  DisplayPort offers a maximum transmission distance of 3m over passive cable and in theory up to 33m over active cable.  There are 20 pins in a DisplayPort connector, with pins 19 and 20 being used for 3.3V, 500mA power on active cables.  DisplayPort cables can be up to 15m long, but quality decreases with length.

DisplayPort is currently available in three versions:

  • DisplayPort 1.1:  Maximum data transfer rate of 8.64Gbps
  • DisplayPort 1.2:  Maximum data transfer rate of 17.28Gbps; introduces mini-DisplayPort connector, and support for 3D
  • DisplayPort 1.3:  Maximum data transfer rate of 32.4Gbps with support for 4K, 5K, and 8K UHD displays.
DisplayPort & Mini DisplayPort (MiniDP or mDP)

DVI

DVI was designed to replace VGA while also being compatible with VGA signals.  It was developed to be an industry standard for transmitting digital video content to display devices at resolutions as high as 2560×1600.  Common devices that utilize the DVI connection are computer monitors & projectors. The DVI connector may have one of three names depending on the signals it supports:

  • DVI-A (analog only)
  • DVI-D (digital only)
  • DVI-I (both digital and analog)
DVI Connector

Multipurpose Cables

Cables that can perform more than one function, such as combining the ability to charge batteries and transfer data.

Lightning

The Lightning connector is used for both charging batteries and transferring data. Apple iOS devices up through the iPhone 4 and 3rd-generation iPad used Apple’s 30-pin connector.  In 2012, iOS devices began using the 8-pin reversible Lightning connector.  However, the iPad Pro uses the USB Type C (USB-C) connector. The data transfer rates are about the same as with the USB 2.0 standard.

iOS Lightning Connector

Thunderbolt

Thunderbolt is a high-speed peripheral connection standard originally introduced by Apple for its macOS desktop and laptop computers.  Thunderbolt has also been adopted by some manufacturers of computers and motherboards that use Microsoft Windows. Thunderbolt allows the connection of external peripherals to a computer. Thunderbolt 1 & 2 use the same connector as Mini DisplayPort (MDP), whereas Thunderbolt 3 re-uses the USB-C connector from USB.  Thunderbolt is also used for high-speed storage, including external drives, network attached storage (NAS), and Redundant Array of Independent Disks (RAID), as well as for high-resolution video. Thunderbolt also supports daisy-chained peripherals.  In Thunderbolt, a cable from the computer connects to the first device in the chain. The device has two Thunderbolt ports, so another device is connected to the second port and so on. If storage and display devices are mixed on a single Thunderbolt daisy chain, the display needs to be the last device.

Thunderbolt Versions
*The connectors are the same shape, but the cables are not interchangeable.
USB-A & Thunderbolt Cables

Because of Thunderbolt’s high bandwidth, it can be connected to docks that feature multiple port types.

Typical Docking Station

USB

Univeral Serial Bus is a plug-and-play interface that allows a computer to communicate with a peripheral and other devices.  USB ports can be used for input devices such as keyboards, mice, and scanners; storage devices such as flash drives, optical drives, and external hard drives; output devices such as printers, multifunction devices, and even displays; and adapters for both wired and wireless networks.  A single USB port (also known as a root hub) can connect to multiple devices when a USB hub is connected to the port.

Typical USB Type A Connector

USB-C

USB-C is an industry standard connector for transmitting both data & power on a single cable. The USB-C connector is easier to connect (reversible; no up or down side to the plug) and with the appropriate adapter allows backward compatibility to USB 2.0. The USB-C standard refers to the connector type on the cable, not the data transfer rate of the cable. USB-C can handle any data rate from USB-2 to USB-3.1.

USB-C connector

USB 2.0, USB 3.0, and USB 3.1

Three standards for USB ports are included on the A+ certification exam:

  • USB 2.0 (Hi-Speed)
  • USB 3.0 (SuperSpeed); also known as USB 3.1 Generation 1
  • USB 3.1 (SuperSpeed+); also known as 3.1 Generation 2
Current USB Versions
High-amperage USB 3.0 ports for charging tablets are marked in yellow.
**Also known as USB 3.1 Gen 1

With any version of USB, a single USB port on an add-on card or motherboard is designed to handle up to 127 devices through the use of multiport hubs and daisy chaining hubs.  USB devices are Plug and Play (PnP) devices that are hot swappable.

Peripheral Cables:  Serial

A serial cable is a cable used to transfer information between two devices using a serial communication protocol. The form of connectors depends on the particular serial port used, although serial cables did conform to the RS-232 standard. Serial means that the data bits flow in a line, one after the other, over the cable.  Serial connections were designed for the relatively low speed of telephone modem communication but were also used for other devices, such as keyboards, mice, and other peripheral devices. USB cables have replaced serial cables, but it is possible to use a USB to serial adapter to connect to an older machine, if necessary.

RS-232 Serial Cable

Hard Drive Cables

Hard drive cables are built to carry data to and from the motherboard.

SATA Cables

Serial ATA is a computer bus interface that connects host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. SATA cables are next-generation serial cables that carry high-speed data. SATA cables can be used internally or externally. SATA cables housed inside of computer cases offer the advantages of high speed and better airflow inside of the casing. External SATA (eSATA) cables allow for external drives to be mounted at the same data rate and provide better shielding to protect the cable & the data.

SATA Cable

IDE Cable

An Integrated Drive Electronics cable (also known as an ATA or PATA [parallel ATA] cable) that connects devices to a motherboard inside of a computer case. Older hard drives typically have IDE connectors, and an IDE cable is one that accommodates them.  Presently SATA & SSD storage drives are more common. An IDE cable typically has three:  one for the motherboard that splits into two connectors.  This way, you can attach two hard drives to a motherboard with only one cable.

IDE Cable/Connectors

SCSI

Small Computer System Interface is a set of standards for physically connecting and transferring data between computers and peripheral devices. SCSI cables have mostly been replaced by SATA cables inside of computers. The advantages of a SCSI drive system is that up to 7 (or sometimes 15) SCSI drives can be daisy chained together in comparison to an IDE connector that supports only 2 drives.

SCSI Cable

Adapters

Physical cable adapters are often the short-term (and economical) answer to technical compatibility problems during an upgrade cycle.

DVI to HDMI

Due to HDMI using the same video signals as DVI, DVI to HDMI cables and adapters are widely available. Typically these adapters only allow for video signals to be transmitted, but some newer graphic cards allow for HDMI audio over DVI.

DVI to HDMI adapter

USB to Ethernet

USB to Ethernet adapters enable a device without an Ethernet port to connect to a wired network.

USB to Ethernet adapter

DVI-I to VGA

DVI-I includes both VGA-compatible analog video and DVI digital video. 

DVI to VGA adapter