Comptia A+ Core 1 Study Guide

Steps a technician uses to solve a problem. CompTIA A+ defines six steps: identify the problem; establish a theory of probable cause; test the theory to determine cause; establish a plan of action to resolve the problem and implement a solution; verify full system functionality and if applicable implement preventive measures; and document findings, actions, and outcomes.

Motherboard, CPU, RAM, Hard Drives; Every other device is a Peripheral.

Monitors, Web Cameras, Keyboards, Mice, Game Controllers,

High Definition Multimedia Interface

A port that transmits digital video and audio (not analog transmissions) and is slowly replacing VGA and DVI ports on personal computers.

An older standard type of plug and connector for computer display devices

Uses a type of connector. Creates a Wired Network

Older connector for Keyboards and Mice

25 pin female port used by older printers (colored Purple)

Oldest connection port on computers. Used to connect items like a monitor.

Port used to connect your monitor (or other visual output device) to your computer. Uses an Analog signal.

Early-gen video connector. Is an analog video signal that carries the video data as two separate signals (brightness and color).

A smaller version of DisplayPort that is used on laptops or other mobile devices.

Removable data storage

Hard drives, optical discs, removable media drives, etc.

CPU, RAM, Mass Storage, and an Operating System. Laptops, mobile devices, and internet of things (IoT) devices

1 Billion cycles per second

1 million cycles per second

Any CPU will take the beat from the System crystal and multiply it. Multipliers are built in the CPU itself.

Running a processor at a higher frequency than is recommended by the manufacturer, which can result in an unstable system, but is a popular thing to do when a computer is used for gaming.

resulted in only minor changes to CPU internals but substantially improved performance by integrating multiple processing cores and memory caches on a single chip and by increasing raw CPU speed.

A technology that permits quicker processing of information by enabling a new set of instructions to start executing before the previous set has finished.

When the decoding step of the machine cycle takes more than one clock cycle. CPU Cache related

64k of RAM. So fast it runs at Multiplied speed of the CPU

128-256k of RAM, Runs at half of the clock multiplied speed.

Megabit size. Runs at base motherboard speed. allows a CPU to avoid a stall.

Defines how the different types of Caches are efficient in handling the right piece of code up to the CPU itself.

Works between RAM and the CPU.

has Pins. AMD

has Pads. Intel

Mainstream Socket type, moving into the enthusiast side. Intel Socket

Enthusiast world. very high-end processors. Intel Socket

mainstream AMD socket

Used on enthusiast, high-end. AMD socket

The mount where a CPU connects to the Motherboard

Identifier on the CPU on the right position to drop the CPU into a Socket.

If you purchase a CPU packaged in this way, you will need to separately purchase a fan and heat-sink assembly.

A special compound used between CPUs and heat sinks. It fills in microscopic gaps and helps draw heat from the CPU into the heat sink where it is dissipated.

"Original" RAM. Synchronized to the system Crystal. 168 Pins. Only type of RAM that has 2 Notches. Usually ran at what the motherboard speed was.

Type of DRAM that makes two processes for every clock cycle. 2 bits of information. 184 Pins.

Increases the data transfer rate by increasing the operational frequency of the RAM chip and by increasing the prefetch buffer from 2 bits to 4 bits per chip. 240 Pins. 4x faster than SDRAM, 2x faster than DDR.

A version of SDRAM that is faster than DDR2 memory and that can use triple channels. 240 Pins.

the fastest RAM that is described on the exam. Most common RAM. Moves data at MT/s (Mega Transfers) 288 Pins.

Different motherboards support a specific RAM technology. We measure RAM speeds using DDR or PC ratings.

measured in megabytes or gigabytes. Stores a certain amount of bytes that we use.

RAM stick with RAM chips soldered to both sides of the stick. May only be used with motherboards designed to accept double-sided RAM. Very common.

This type of RAM only has memory on one side of a stick.

Having flexibility in our system for the amount of RAM it can have. Using multiple sticks of RAM. Ram being sold in pairs usually.

Form of DDR, DDR2, and DDR3 memory access used by many motherboards that requires two identical (size and speed) sticks of DDR, DDR2, or DDR3 RAM. Channels allow to talk to both sticks at the same time (faster)

Error Correction Code RAM. Contains extra chips to check for RAM errors. Only able to be on motherboards that can use it. has an extra chip or two if a chip dies on the RAM.

A type of memory module used in laptop computers that uses DIMM technology. A DDR3 SO-DIMM has 204 pins. A DDR2 or DDR SO-DIMM has 200 pins. Older, outdated SO-DIMMs can have 72 pins or 144 pins. Their just smaller.

Allows your system to query the RAM chip and ask what's the Capacity, Speed, Tech, and who made it and model number.

Programing that enables interaction with the motherboard before OS loads. Stored in nonvolatile media, thus called firmware. Contains the settings for the boot-up process.

Chip contains the software (firmware) on the MOBO. Now, usually stored on a EEPROM chip that can be electronically updated through a software updated from the manufacturer.

Runs at boot, requesting devices to self-check. A self-diagnostic program used to perform a simple test of the CPU, RAM, and various I/O devices. Is performed by startup BIOS when the computer is first turned on, and is stored in ROM-BIOS.

Enables custom information about changeable devices. Is the component that remembers your system settings when you power the computer down. Enables changes to CPU frequencies, RAM timings, BIOS passwords, boot options, and more.

Series of audible tones produced by a motherboard during the POST. These tones identify whether the POST has completed successfully or whether some piece of system hardware is not working properly. Consult the manual for your particular motherboard for a specific list of beep codes.

Enable testing of "dead" computers. Lets you know the problem before the POST and must be related to the power, CPU, the RAM, or MOBO.

Used to replace BIOS. More advanced interface between hardware and the OS. Maintains support for legacy BIOS systems

A separate chip, stores the info that describes specific device parameters. It does not store programs; it only stores data that is read by BIOS to complete the programs needed to talk to changeable hardware. It also acts as a clock to keep the current data and time (Sometimes called the Real Time Clock).

ROM chip that we "Flash" it (reprogram it).

The battery on the motherboard used to power the CMOS chip when the computer is unplugged. if the battery dies, all system information disappears.

Flashing the ROM Updates the firmware on flash chip.

A set of specifications on the size, shape, and configuration of a computer hardware component such as a case, power supply, or motherboard.

The most common (standard) form factor for PC systems presently in use. ATX motherboards and cases make better use of space and resources than did the earlier AT form factor.

Small form-factor. Similar mounting points and power as ATX

A smaller version of the MicroATX form factor. Also called ITX. about the smallest common form factor.

A family of motherboard form factors used in smaller systems, smaller than the Mini-ITX. much more uncommon.

A plate installed on the rear of a computer case that provides holes for I/O ports coming off the motherboard. Fixed shape for all main form factors

A part of a motherboard that acts as a traffic director for data. (Northbridge, Southbridge). Today's are Southbridge (CPU handles Northbridge functions). the Model number defines what you can have on a motherboard (RAM capacity, USB capabilities, etc.)

The Northbridge chipset deals with the communication between the CPU, the memory. Handles the faster stuff.

The Southbridge chipset manages all onboard peripheral devices. Handles the slower stuff.

Newer type of cable that joins various drives, such as the optical drive or hard drive, to the motherboard of the computer. 7 pin connector.

Is a high-speed serial computer expansion bus standard designed to replace the older PCI, PCI-X, and AGP bus standards. Sends data on one wire and receives data on one wire. Most common expansion bus, it offers multiple Lanes.

A bus common to personal computers that uses a 32-bit wide or a 64-bit data path. Several variations of PCI exist. On desktop systems, one or more notches on a PCI slot keep the wrong PCI cards from being inserted in the PCI slot.

Low mounting posts that are used to secure a motherboard into a case

Offers standardized standouts for mounting various motherboard form factors.

To get its power, the fan power cord connects to a 4-pin fan header on the motherboard. The fan connector will have three or four holes. A three-hole connector can fit onto a 4-pin header; just ignore the last pin. A 4-pin header on the motherboard supports pulse width modulation (PWM) that controls fan speed in order to reduce the overall noise in a system. If you use a fan power cord with three pins, know that the fan will always operate at the same speed.

Connects to the 24-pin ATX power cable of a power supply unit which supplies power to the motherboard.

This is the most common power supply on the market today. It includes a second motherboard connector to provide dedicated power to the CPU.

Computer power connector used by optical drives, hard drives, and case fans. Keyed to prevent it from being inserted into a power port improperly.

This powers a floppy disk drive. Sometimes other components use it as well.

provides connectors at the power supply end, allowing unused cables to be detached from the power supply, producing less clutter, a neater appearance and less interference with airflow.

a 15-pin flat power connector that provides power to SaTa drives.

A dedicated power connector for higher-end video cards.

A piece of metal, with cooling fins, that can be attached to or mounted on an integrated chip (such as the CPU) to dissipate heat.

A 4-pin Fan connector that connects directly to the CPU

resets all CMOS settings. goes back to defaults

A scheme used for specifying locations of blocks on a hard disk.

It is a type of disk drive that integrates the drive controller directly on the drive itself. Such as PATA (parallel) or SATA (serial) hard drives.

Is a the most common standard for connecting Mass Storage into computer systems

External Serial Advanced Technology Attachment - an external interface for SATA. Transfer rate of 3Gbps

is a data storage device that uses magnetic storage to store and retrieve digital information using one or more rigid rapidly rotating disks (platters) coated with magnetic material.

A type of that SSD come in a couple of formats, such as an add-on expansion card and a 2.5 inch drive. Higher speeds than regular M.2 SSD's as well as SSD's. 1 Notch.

SSD Storage that fits/connects onto a Motherboard.

Small Computer System Interface. Set of standards used to connect peripherals to computers. Commonly used for SCSI hard disks and/ or tape drives.

A SCSI interface that uses a serial connection similar to SATA. Modern standard.

SCSI connection via Ethernet Cable. Modern standard.

The older and slower ATA standard.

A hard disk drive where data is written on to lots of disks at the same time. If one disk gets damaged, data can be accessed from another disk.

File blocks are split between two or more physical drives. High performance and data written quickly. No redundancy. A drive failure breaks the array. Speed.

A mirrored volume stores data to two duplicate disks simultaneously. Redundancy. Slower.

File blocks are striped along with a parity block. This requires at least three disks. Efficient use of disk space as files aren't duplicated, but space is still used for parity. High redundancy. Data is available after drive failure but parity calculation may affect performance. Minimum 3 Drives. Can only lose 1 drive.

Double-parity RAID (redundant array of independent disks), also called diagonal-parity RAID, Advanced Data Guarding (RAID_ADG), is a method of protecting against multiple storage drive failures by creating two sets of parity data on an array of hard disks. Six total drives, five actual data drives. The drives are striped with parity interleaved to optimize performance. Minimum 4 drives. lose up to 2 drives.

a combination of RAID 1 and RAID 0 that requires at least four disks to work as an array of drives and provides the best redundancy and performance.

Multiple RAID types - combine RAID methods to increase redundancy

unlocks some of the advanced features of SATA, such as hot-swapping and native command queuing. You can enable AHCI in the CMOS if you want it enabled. You need to make sure you enable it before you install the OS because if you don't you will get BSOD.

A method of implementing RAID that relies on an externally attached set of disks and a RAID disk controller, which manages the RAID array. Has its own BIOS that comes with a special system setup to configure the RAID array. Look The completed array looks like a single drive.

1. Back it up. 2. Mental re-install 3. Triple Check

If hardware RAID is implemented in the computer, the problem is usually with the RAID controller. Check the controller, and replace as necessary. If software RAID is implemented, make sure that the BIOS is set to RAID. You should also check all RAID connections. Finally, test the individual RAID drives. If one of the drives has failed, replace it and restore the data.

This indicates a dying hard drive and could happen if the read/write head crashes.

Querying a drive to see its health.

Not enough RAM in the system, Disc crashes.

an actual clicking noise. A typical symptom of either a hard disk drive having read/write problems or from a failing cooling fan. terminal issue.

System cannot start, possibly due to BIOS/UEFI boot order, damage to operating system files or other causes

The drive itself has a formatting problem.

This message indicates a software issue with loading the operating system.

Boot Order problem. This can be caused by a problem with the boot settings within the BIOS.

These could be related to BIOS problems or OS problems. Problems with a bad driver may also be responsible.

An optical disc technology that uses a red laser beam and can hold up to 700 MB of data.

Disk that can store up to 680 MB of data; data can only be read from it.

A file system used on optical discs and widely supported by different operating systems.

Optical disc on which users can write once, but not erase, their own items

CD technology that accepts multiple reads/writes like a hard drive.

A CD-like optical disk with a capacity of 4.7 GB or more that can hold a full-length commercial movie.

is a high-capacity optical disc that users can read but not write on or erase. Most common type of optical media today.

able to use multiple layers on the same side of a DVD for reading and writing storage.

able to use both sides of a DVD for reading and writing storage.

a burn once DVD

Optical disc format that stores 25 or 50 GB of data, designed to be the replacement media for DVD. Competed with HD DVD.

A Blu-ray disc on which you can record data once.

A high-capacity rewritable Blu-ray format.

A standard input and output connection for many modern peripherals.

USB: Low speed: 1.5 megabits/sec. Full speed: 12 megabits/sec.

USB: 480 megabits/sec

USB: 5 Gigabits/sec. Had some compatibility issues.

USB: 5 Gigabit/s. The fix for USB 3.0

Superspeed+ 10Gbits/s.

first type of connector with USB. incredibly popular today.

A USB connector type that usually plugs into scanners and printers.

USB type for connecting small devices

USB Type that is popular with android devices.

A small USB connector used by USB 3.0 devices. The connectors are not compatible with regular Micro-B connectors.

USBType that can be plugged in either way. compatible with 10Gigbit speeds.

USB Type connector that is able to bring power to a device, but not able to do data transfer. Usually red, orange, or yellow colors on connectors.

Upstream connection for USB. usually in micro-B and others for the connections that are part of the Device, Not the back of a computer.

Part of the host controller that makes the physical connection to the USB ports.

Allows multiple USB devices to be connected to a single USB port. up to 127 devices.

some kind of software that can lock certain USB ports or whitelist certain USB drives.

Base/Core drivers for devices that make sure Keyboards and Mice work.

10 Gbps; x2 channels. Apple connector

20Gbps Apple connector

40 Gbps. USB type-C connector. Apple connector

an input/output connection developed by Apple and Intel. It carries data and display signals on a single cable. It also can be used to power peripherals with 10 watts of power. It is a dual-protocol technology that works with PCI Express and DisplayPort technologies.

A connector for power and communication for newer mobile Apple products. charging devices, data transfer. charging iPhone, Ear Pods. 5Gbps

Allows you to connect multiple PCs to a single set of input/output devices.

Digital audio connector found on many sound cards. Users can connect their computers directly to a 5.1/7.1 speaker system or receiver. Comes in both a coaxial (3.5mm jack) and an optical version (SPDIF)

A camera, either built in or that can be plugged into a computer, used to send images and video over the internet. Are most often used for video chat.

A slot or compartment into which the flash memory card is inserted.

A type of memory card used in digital cameras, tablets, cell phones, MP3 players, digital camcorders, and other portable devices.

Olympus brand camera flash memory card.

input devices that capture printed images or documents and convert them into electronic digital signals (i.e., into binary representations of the printed image or document) that can be stored on computer media

Most popular form of consumer scanner; runs a bright light along the length of the tray to capture an image. Can only scan one page at a time.

A type of scanner that reads printed coded labels.

A circuit board with specific functions that augment the computer's basic functions and provide connections to other devices; examples include USB ports, sound cards and the video cards.

CompTIA's name for a standard desktop computer. Runs desktop appli- cations and meets recommended requirements for selected OS.

Desktop computer system that do not offer the full functionality of a PC. Meets Minimum Requirements. Basic Applications.

Powerful computer system. Powerful multicore processor, high-end video, Maximum RAM.

A computer system that hosts guest operating systems and that must have maximized RAM and CPU enhancements in the form of multiple CPUs with multiple cores.

A dedicated computer system used to provide disk storage on a network. It's often a small device that is easy to plug in and use. Shares files. High speed network cards (Gigabit NIC minimum). RAID arrays.

A multimedia computer system exhibiting higher performance and responsiveness than standard machines making them ideal for fast paced games of skill. These computers must have CPU enhancements video enhancements specialized audio and enhanced cooling.

A computer system optimized for editing the audio and video tracks of video files. These workstations must have video enhancements specialized audio and specialized drives.

An older backlighting technology that uses one or two fluorescent tubes to light a monitor panel.

A diode that will produce light when current flows through it.

Doesn't use a backlight, as the pixels make their own light.

Technology that bounces light off microscopic mirrors on a computer chip used by small computer projectors.

is compromised of individual picture elements (pixels); total pixels across and down is the resolution.

technology produces an image by filtering light through a layer of liquid crystal cells

Backlight for conventional LCD displays.

Digital Visual Interface. Uses a digital signal.

CPU and a GPU together

Connects a group of computers in close proximity, such as in an office building, school, or home

a system for connecting a number of computer systems to form a local area network, with protocols to control the passing of information and to avoid simultaneous transmission by two or more systems.

A unique identifier assigned to network adapters by the manufacturer. This address is six octets in length (12 characters) and is written in hexadecimal. 48bit address.

First 6 characters in a MAC address. unique in every network card.

An older device that uses its ports to connect devices (computers, printers, etc.) together. not used much anymore.

A modern computer networking device that connects network segments.

A base-16 number system that uses sixteen distinct symbols 0-9 and A-F to represent numbers from 0 to 15. allows us to string long binary values into shorter segments.

A network that connects devices in geographically separated areas.

A device that transfers data from one network to another in an intelligent way

As opposed to physical addressing, the process of assigning organized blocks of logically associated network addresses to create smaller manageable networks called subnets. IP addresses are one example of logical addressing.

(Data Over Cable Service Interface Specification) A security technology used for filtering packets and maintaining customer privacy on cable Internet services

A type of coaxial cable characterized by a 50-ohm impedance and a 24 AWG core.

A type of coaxial cable characterized by a 75-ohm impedance and a 20 or 22 AWG core, usually made of braided copper. Less expensive but suffering greater attenuation than the more common RG-6 coax, RG-59 is used for relatively short connections.

A type of coaxial cable with an impedance of 75 ohms and that contains an 18 AWG core conductor. RG-6 is used for television, satellite, and broadband cable connections.

Cables made of copper wires that are twisted around each other and are surrounded by a plastic jacket (such as traditional home phone wire).

A phone line connection or port found on modems, telephones, and house phone outlets.

A cable that transmits data at close to the speed of light along glass or plastic fibers.

A type of fiber optic cable that carries multiple light signals on a single strand.

A type of fiber optic cable that carries a single optical signal.

explains how cable has been engineered and how it can safely transfer data.

100 Mbps

1000 Mbps (1Gbps)

1Gbps up to 100m. 10Gbps up to 55m

Supports 10-Gbps networks at 100-meter segments

is save for installation between a dropped ceiling and structural ceiling where air circulation takes place -made from a special; plastic which retards fire and produces less smoke than other cables

a cable not so resistant to fire.

a rating for cables that go between floors, medium fire resistance.

OOGBBGBB

GGOBlBlOBB

The wire pairs in the cable connect to the same pin numbers on each end

A twisted pair patch cable in which the termination locations of the transmit and receive wires on one end of the cable are reversed.

A method for uniform, enterprise-wide, multivendor cabling systems specified by the TIA/EIA 568 Commercial Building Wiring Standard. Structured cabling is based on a hierarchical design using a high-speed backbone.

A cable rack that connects and manages wiring used for telecommunication between a service provider and intermediate distribution frames (IDFs). The MDF connects private or public lines coming into a facility with the networking devices in the facility.

network/telephone cabling runs from closets to workstations always use solid cord (less flexible)

A wall- or rack-mounted panel where cables converge in one location.

This tool is used to permanently connect wires to patch panels and RJ-45 wall jacks

a tool that helps locate cables.

Detects the location of a fault in a copper cable by sending an electric signal down the copper cable and measuring the time required for the signal to bounce back from the cable fault. A TDM can then mathematically calculate the location of the fault.

A cable that uses a single solid wire to transmit signals. solid copper wires.

a cable that has its wires stranded for flexibility.

Portion of an Ethernet frame used for error checking, most commonly with the CRC algorithm.

Networking cable that has four twisted pairs of copper wire and a flexible outer coating.

Copper network cable that has two or four pairs of twisted wires shielded by a braided mesh and covered with an outside coating.

In IPv4 addressing, a 32-bit number that, when combined with a device's IP address, indicates what kind of subnet the device belongs to.

A number that uniquely identifies each computer or device connected to the Internet. Has four octets between 0-255

The Internet Protocol version 4 is the dominant protocol for routing traffic on the Internet, specifying "to" and "from" addresses using a dotted decimal such as "122.45.255.0".

An IP address that is manually assigned to a device and remains constant until it is manually changed.

1-126 Leading bits. 128 Networks. 16,777,214 Hosts per Network. Default Subnet Mask 255.0.0.0

128-191 Leading bits. 16,384 Networks. 65,534 Hosts per Network. Default Subnet Mask 255.255.0.0

192-223 Leading bits. 2,097,152 Networks. 254 Hosts per Network. Default Subnet Mask 255.255.255.0

224-239 Used for multicast testing,

240-255 Reserved.

An IP address that is used on a private TCP/IP network that is isolated from the Internet.

10.0.0.0 - 10.255.255.255

172.16.0.0 - 172.31.255.255

192.168.0.0 - 192.168.255.255

A address used for testing of the host itself. 127.0.0.1

Translates the private IP address to a public address for routing over the Internet

Dynamically assigns IP address information (for example, IP address, subnet mask, DNS server's IP address, and default gateway's IP address) to network devices.

Feature of Windows that automatically assigns an IP address to the system when the client cannot obtain an IP address automatically. will always give a 169.254.X.X address

The Internet Protocol version 6 provides a large number of new addresses to route Internet traffic, using "from" and "to" addresses written as colon-hexadecimal notation, such as "fe80::42:acff:feaa:1bf0".

The address that a computer running IPv6 gives itself after first booting. The first 64 bits of a link-local address are always FE80::/64.

brought down from actual router itself. computer automatically generates the 2nd half.

The address on a host where an application makes itself available to incoming data. 0-65535

port numbers in the range of 1-1024 that identify network applications that are well known such as web, email, and remote login applications

Ports ranging from 1024 to 49151; accessible to network users and processes that do not have special administrative privileges.

TCP/IP ports in the range of 49,152 through 65,535, it is spun up by your system every time it makes a connection to give a return port number for whatever server you might be connecting to.

A set of rules governing the exchange or transmission of data between devices.

Two different protocols working together to help get the data between your systems. A client talks to the server, waits for the server to hear you, and then they start doing what they do.

connectionless protocol. Protocol that operates instead of TCP in applications where delivery speed is important and quality can be sacrificed.

Single packet only. A core protocol in the TCP/IP suite that notifies the sender that something has gone wrong in the transmission process and that packets were not delivered. (the /ping command).

A unit of data at any layer of the OSI model.

An IP header, followed by the data encapsulated after the IP header, but specifically not including any headers and trailers for layers below the network layer.

The connection-oriented payload of an IP packet. Works on the transport layer.

A connectionless networking container used in UDP communication.

Internet service that translates domain names into IP addresses. the DNS system is resolving a website address name into an IP address.

The predecessor to DNS, a static text file that resides on a computer and is used to resolve DNS host names to IP addresses. The HOSTS file is checked before the machine sends a name resolution request to a DNS name server. The HOSTS file has no extension.

One of several collections of servers scattered around the world that maintains the databases of all domains that reside in any given top-level domain.

Domain name that specifies its exact location in the tree hierarchy of the domain names system. has a 256 character limit.

Command-line program in Windows used to determine exactly what information the DNS server is providing about a specific host name.

The Active Directory service that manages the process that allows a user to sign on to a network from any computer on the network and get access to the resources that Active Directory allows.

a type of peer-to-peer network where each computer shares files, folders, libraries, and printers with other computers in the homegroup. access to the homegroup is secured using a homegroup password.

Cable used to interface with a Cisco device.

A small business office with between 1 and 10 users.

gives control on network bandwidth by many different criteria

A protocol that identifies devices connected on the local area network and allows them to automatically exchange information.

A protocol used to monitor and manage network devices, such as routers, switches, and servers.

A LAN that, using VLAN-capable switches, places some (or any on the more expensive VLANs) systems on virtual broadcast domains.

A switch that can be configured via a command-line interface and sometimes can be configured in groups. Usually, they are assigned their own IP addresses. VLANs can only be implemented through managed switches.

enables devices to connect to a wireless network to communicate with each other. a bridge between an ethernet network and a wireless 802.11 network.

Wireless Ethernet standard more commonly known as Wi-Fi. based on Industrial, Scientific, and Medical (ISM) Radio Bands.

A wireless configuration that uses one or more WAPs to connect wireless workstations to the cable backbone.

The user-supplied network name of a WLAN; it can generally be alphanumeric from 2 to 32 characters.

Decentralized wireless network mode, otherwise known as peer-to-peer mode, where each wireless node is in meshed contact with every other node. your computer becoming a WAP itself.

An antenna that detects signals from all directions equally (also called omnidirectional antenna).

A directional antenna that has a planar surface and is usually mounted on a wall or column.

unidirectional antenna; works well transmitting and receiving signals in some directions but not in others

Runs frequencies 2.412-2.4884 GHz. There are 14 different channels. each channel takes a different piece of the band.

Runs frequencies 5.150-5.875 GHz. The channels that start with 36 to 64 with no Odd numbered channels. Then goes from 100 to 144 (no odd's still), then 149 to 165.

54 Mbps - 5 GHz. earliest extension to 802.11

11 Mbps, 2.4 GHz.

54 Mbps, 2.4 GHz.

100Mbps, 2.4GHz and 5 GHz. backwards compatible with any wireless nic. MIMO (multiple in/multiple out) allows a single wireless access point to use multiple antennas to change its radiation signal where it zeros in on a device.

5GHz 1300mbps. creates Multi-user MIMO. can zoom in on multiple clients at a time.

A LAN that uses wireless connections for some or all of its transmissions. it's like ad hoc mode but on steroids.

product tags with tiny chips containing information about the item's content, origin, and destination

a very short-range wireless connectivity technology designed for cell phones and credit cards

Provide communication over a short distance that is intended for use with devices that are owned and operated by a single user

100mW of power. 100m range.

2.5mW of power. 10m range.

1mW of power. 1m of range.

Wireless PAN technology that transmits signals over short distances between cell phones, computers, and other devices. functions as point-to-point.

• Interference - Something else is using our frequency • Signal strength - Check the signal and antenna locations • Incorrect channel - Usually automatic, try tuning manually • Bounce and latency - Multipath interference; flat surfaces • Incorrect access point placement - Locate close to the users

In this situation, a computer can connect to the network but cannot access a specific resource on the network. The problem could be because the user does not have permission to access the resource. If you can ping the resource but cannot access the resource by its host name, the DNS server could be down. The problem could lie with the remote resource. See if other computers can connect to it.

This is usually caused by interference, incorrect cabling, a malfunctioning NIC, router misconfiguration, or switch misconfiguration. If only one client is experiencing the problem, check that computer's cabling and NIC. You only need to check for interference, router misconfiguration, or switch misconfiguration if more than one client is experiencing this problem.

A network problem in which a device's connection goes in and out; most likely caused by physical problems, such as a loose or damaged cable or antenna wire, or network signal strength/interference problems, too many people on the same band.

A centralized location for techs and administrators to manage all aspects of a network.

a connection that is extremely slow, but is available wherever there is a telephone; a modem uses the telephone line to transmit and receive data; this method of connection is known as dial-up

An international telephone system that carries analog voice data.

Uses terminal adaptors. a completely digital line. run at 64Kbps or128Kbps. allowed you to still use your telephone while on the internet.

A communications method for transferring files between computers on the Internet. most things done on port 21. almost all web browsers are FTP clients.

When a firewall opens a port because a computer behind the firewall initiates communication on another port.

The Internet standard protocol for transferring e-mail messages from one computer to another (to an SMPT server). Port 25.

A protocol used to retrieve email from a mail server. POP3 is a later iteration of the POP protocol, and can be used with or without SMTP. Port 110

A protocol used to retrieve email messages. IMAP is similar to POP3, but with some advanced features. The main difference between the two is that IMAP generally leaves the email on the mail server. Port 143

A computer system (or an application program) that intercepts internal user requests and then processes that request on behalf of the user.

A private data network that creates secure connections, or "tunnels," over regular Internet lines

a virtual, private pathway over a public or shared network from the VPN client to the VPN server

the network of products embedded with connectivity-enabled electronics

A form of wireless communications frequently used in security systems and heating and cooling control systems.

A short-range low-power network technology used for the Internet of Things.