220-1101 Hardware Study Guide for the CompTIA A+ Core Series Exam
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General Information
Hardware concepts are one of the most heavily emphasized areas of IT assessed on the CompTIA A+ 1101 exam. Around 25% of the questions on the test pertain to this area. You’ll need to be highly competent in identifying, using, and connecting hardware components and devices. The recent increase in remote work also makes it necessary to know about different devices that support that workforce. As you study, keep in mind that nearly all the questions (86%) about hardware will begin with a scenario.
Basic Cable Types: Connectors, Features, and Purposes
You must be able to describe different cable types and their characteristics and uses, including connector types, features, and purposes.
Network Cables
Network cables are used to connect devices such as computers to networking equipment. There are three primary types of network cable: coaxial, twisted pair, and fiber. A cable is the medium through which data is transferred from one device to another.
Copper
Copper is the most common medium used in both coaxial and twisted-pair cables. Categories are used to describe performance ratings of twisted-pair cables. Commonly referred to as Cat cables, Category 1 through 8 exist, but for the purposes of the CompTIA A+ exam, we are only concerned with the most common ratings, Category 5 through 6a, and their corresponding transmission speeds and distance limitations. All Cat cables 2 through 8 are composed of four pairs of twisted-pairs totaling eight individual cables in one cable sheath.
Cat 5—Category 5 cables have a transmission rate of up to 100 Mbps over a max distance of 100 meters.
Cat 5e—Category 5e cables have a transmission rate of up to 1 Gbps over a max distance of 100 meters due to the separation of the four sets of twisted pairs from one another and an increased number of twists in the cable pairs. This results in less interference.
Cat 6—Category 6 cables have a transmission rate of up to 10 Gbps over a max distance of 55 meters.
Cat 6a—Category 6a cables have a transmission rate of up to 10 Gbps but have an increased distance capability of up to 100 meters.
Coaxial—A coaxial cable is a single copper-cored cable contained in an inner insulation layer. This inner layer is further contained in a wire mesh conductor. The entire cable is then further protected in an outer insulation layer. Coaxial cables are not as commonly used in modern networks, but some usage may still be seen with cable and satellite devices. Coaxial cables are specified by the Radio Guide (RG) system. For the purpose of the test, you need to be familiar with RG-6, which is made of a solid copper core used with satellite/cable modems, and RG-59, which is made of a solid copper core and used for cable television.
Twisted Copper Pair
A twisted copper pair is a twisted pair cable made of copper. The cable consists of pairs of individual wires twisted into pairs that are then twisted together. The cable is contained within an insulated jacket. Ethernet cables are twisted pairs. There are two types of twisted copper pairs: shielded twisted pair (STP) and unshielded twisted pair (UTP).
Unshielded Twisted Pair
An unshielded twisted pair (UTP) is made of two to four pairs of twisted wires. The pairs of wires in UTP cables are twisted in direct contact with one another. Each wire in twisted pairs is contained within an insulating layer, preventing copper from directly touching copper.
Shielded Twisted Pair
A shielded twisted pair (STP) is made of two to four pairs of twisted wires. Each pair is contained in a layer of braided foil sheathing before being twisted with the other pairs in the cable. This reduces electrical interference. STP is used in Cat 7 and Cat 8 cables.
Direct burial—Direct burial is the practice of burying cables underground. Direct burial cables should be STP cables with an extra waterproof sheathing. It is recommended that direct burial be between six and eight inches underground in a protective PVC pipe and placed away from any other lines that contain electrical current.
Plenum
Plenum is a Teflon-type covering used to cover all types of network cables. Plenum is used in cables that may be exposed to extreme heat or have the possibility of releasing gasses into a ventilation system, such as in ceilings.
Optical
Optical is a transmission method that depends on light pulses for data transfer.
Fiber—Fiber refers to the small strings of flexible glass that are used for optical data transmission. Referred to as fiber optic cables, a fiber is surrounded by a rubberized coating and provides transmission speeds from 100 Mbps to 10 Gbps over a max distance of several miles. Fiber is immune to both electrical interference and wiretapping. There are two basic types of fiber: single-mode and multimode. Single-mode fiber carries only one light path, typically sourced by a laser. Multimode carries multiple light paths and is sourced by an LED. Single-mode has a much longer transmission distance than multimode.
T568A/T568B
Twisted pair wires are color coded for proper referencing. T568A and T568B are the two standards used for RJ-45 wiring connectors. The T568A standard is green/white, green, orange/white, blue, blue/white, orange, brown/white, and brown. The T568B standard is orange/white, orange, green/white, blue, blue/white, green, brown/white, and brown.
Peripheral Cables
Peripheral cables attach peripheral devices to a computing device. They are used to attach things like printers, keyboards, monitors, and USB devices.
USB 2.0—The universal serial bus 2.0 standard has a max speed of 480 Mbps and is referred to as Hi-speed.
USB 3.0—The USB 3.0 standard has a max speed of 5 Gbps and is referred to as SuperSpeed.
Serial—A serial cable is built for serial communications with a corresponding serial connector on the end. The most common serial connection type is DB91, which has nine pins.
Thunderbolt—Thunderbolt is a combination of PCI Express 2.0 x4 and DisplayPort 1.x technology. Thunderbolt was designed primarily for video transmission but can be used by other peripheral devices as well. There are four Thunderbolt standards labeled 1 to 4 with Thunderbolt 1 and 2 terminating in a Mini-DisplayPort connector and Thunderbolt 3 and 4 terminating in a USB-C connector.
Video Cables
A video cable is designed to transmit data to visual display units.
HDMI—The high-definition multimedia interface cable is capable of handling higher motion-picture frame rates and digital audio on a single cable. The most common connector type for an HDMI cable is the Standard A HDMI cable which has 19 pins.
DP—DisplayPort was developed to use less power than previous video cables. DisplayPort is backward compatible with VGA and DVI. DisplayPort is also capable of transmitting both video and audio signals. A standard DP cable has two hooks on it to lock the cable into place.
DVI—The digital visual interface cable was developed to address the shortcomings of analog video transmission. DVI cables are capable of transmitting digital video signals to display units. The three DVI connector standards are DVI-A for analog connection only, DVI-D for digital connection only, and DVI-I for both analog and digital signals. DVI cables are typically white.
VGA—The video graphics array cable is the oldest video standard still in use today. A VGA cable is strictly analog and is typically blue in color.
Hard Drive Cables
Hard drive cables/connectors connect internal components to the motherboard. Hard drive connections, known as drive interfaces, can be either on-board or off-board. Their attachment standard is based on the hard drive’s requirements and consists of circuitry and a header, or port.
SATA—Serial advanced technology attachment is the most common type of drive interface. A standard SATA cable is internal and flat with a terminating connector that can only fit into the motherboard connection port in one way. A SATA data cable has seven pins, while a SATA power cable has 15 pins. SATA revisions 1.0, 2.0, 3.0, and 3.2 support speeds of 1.5 Gbps, 3 Gbps, 6 Gbps, and 16 Gbps, respectively.
SCSI—Small computer system interface is a type of hard drive connector that is most commonly used for storage device connection. SCSI cables can be either ribbon cables or round cables containing 50, 68, or 80 wires. Up to 16 devices, including the motherboard or SCSI controller card, may be connected to one SCSI cable or daisy-chained together.
eSATA—The external SATA cable, as the name suggests, is external to the housing. Standard eSATA cables are for data transmission only and do not provide power. An eSATA that provides power is called Power over eSATA, eSATA+, eSATAp, or eSATA/USB.
IDE—Integrated drive electronics cables, renamed parallel advanced technology attachment (PATA), are 40-pin flat data cables with a colored strip along one edge to indicate the location of pin 1. There are three separate connectors on a PATA cable, one for power and two for drives.
Adapters
An adapter is a device that converts one type of connection or cable technology to another, such as a DVI-to-VGA, DVI-to-HDMI, or USB-to-ethernet.
Connector Types
Connectors are installed at the terminating points of cables to provide connection to compatible components and peripherals. The connector type used depends on the type of cable and the desired receptacle compatibility.
RJ11—A registered jack (J) is a standard for telecommunication network interfaces for voice and data equipment connection to a service provider or carrier. RJ11 is used with twisted pair cables to connect four to six wires to traditional telephone lines of modems.
RJ45—RJ45 is used with twisted pair cables for eight-wire connections. A twisted pair cable with RJ45 connectors is commonly called an ethernet cable.
F-type—An F-type connector (or just F connector) is used with coaxial cables for cable and satellite data connections.
ST—A straight tip connector is a bayonet style connector used with fiber optic cables.
SC—A subscriber connector is a push/pull-style connector used with fiber optic cables.
LC—A lucent connector is a push/pull-style connector used with fiber optic cables that is half the size of an SC, making it more suitable for office and data center usage.
Punchdown block—A punchdown block is an electrical connection device that allows for multiple copper wires to be “punched down” or inserted into a slot providing insulation as well as electrical connection to attached wires.
Micro USB—A micro USB connector is the smallest USB connector type, contains five pins, and is direction dependent.
MiniUSB—A mini USB is the second smallest USB connector type, contains five pins, and is direction dependent.
USB-C—USB-C is the most recent USB connector type containing 24 pins in an oval shape, allowing for reversible connection.
Molex™—Molex is an older two-piece pin-and-socket interconnection type used for drive connections.
Lightning port—Lightning port is an eight-pin Apple proprietary connector type that has reversible orientation.
DB9—The DB91 is a trapezoid-shaped nine-pin connector arranged in two rows of four and five pins. It is used for serial connections to network device consoles or management ports.
1. The term “DB9” is commonly used but is technically incorrect; the proper name is “DE9,” referring to the size of the connector’s shell and the number of pins, with DE indicating a smaller shell size than DB. However, given that this misconception has been prevalent for so long in the industry, the CompTIA objectives use the term DB9.
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