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The CompTIA 220-901 exam is one of two exams requires to obtain the CompTIA A+ (900 series). This exam will cover topics like networking, mobile devices and hardware and network troubleshooting.
A KVM (Keyboard Video Mouse) Switch is used to use a single set of peripherals with multiple physical machines.
A KVM switch (with KVM being an abbreviation for "keyboard, video, and mouse") is a hardware device that allows a user to control multiple computers from one or more sets of keyboards, video monitors, and mice.
KVM_switch - Wikipedia, the free encyclopediaInfrared is a wireless technology that requires a clear path between communication devices. A good example of this, is a TV Remote.
Infrared (sometimes called infrared light and IR) is electromagnetic radiation (EMR) with wavelengths longer than those of visible light and shorter than radio waves. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 THz). IR is commonly divided between longer wavelength thermal infrared that is emitted from terrestrial sources and shorter wavelength near-infrared that is part of the solar spectrum. Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discovered that infrared radiation is a type of invisible radiation in the spectrum lower in energy than red light, by means of its effect on a thermometer. Slightly more than half of the energy from the Sun was eventually found, through Herschel's studies, to arrive on Earth in the form of infrared. The balance between absorbed and emitted infrared radiation has an important effect on Earth's climate. Infrared radiation is emitted or absorbed by molecules when changing rotational-vibrational
Infrared - Wikipedia, the free encyclopediaECC memory is most commonly found in servers because a server has a much higher load and fault tolerance requirement than an average computer or device.
Error correction code memory (ECC memory) is a type of computer data storage that uses an error correction code (ECC) to detect and correct n-bit data corruption which occurs in memory. ECC memory is used in most computers where data corruption cannot be tolerated, like industrial control applications, critical databases, and infrastructural memory caches. Typically, ECC memory maintains a memory system immune to single-bit errors: the data that is read from each word is always the same as the data that had been written to it, even if one of the bits actually stored has been flipped to the wrong state. Most non-ECC memory cannot detect errors, although some non-ECC memory with parity support allows detection but not correction.
ECC_memory - Wikipedia, the free encyclopediaYou are an IT Support Technician for a large office building. A user is complaining their laptop often does not charge or stops charging if they move it. What is most likely the issue?
Laptop's require AC adapters (alternating current) to convert power available in a home or office to DC (direct current). An AC power adapter plugs into the laptop's DC jack. It is called the DC jack because it only accepts DC.
A DC connector (or DC plug, for one common type of connector) is an electrical connector for supplying direct current (DC) power. Compared to domestic AC power plugs and sockets, DC connectors have many more standard types that are not interchangeable. The dimensions and arrangement of DC connectors can be chosen to prevent accidental interconnection of incompatible sources and loads. Types vary from small coaxial connectors used to power portable electronic devices from AC adapters, to connectors used for automotive accessories and for battery packs in portable equipment.
DC_connector - Wikipedia, the free encyclopediaYou need to configure a SOHO network to provide IP Addresses to devices on the network. Which feature should be enabled?
Dynamic Host Configuration Protocol (DHCP) is the protocol responsible for assigning IP addresses.
The Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on Internet Protocol (IP) networks for automatically assigning IP addresses and other communication parameters to devices connected to the network using a client–server architecture.The technology eliminates the need for individually configuring network devices manually, and consists of two network components, a centrally installed network DHCP server and client instances of the protocol stack on each computer or device. When connected to the network, and periodically thereafter, a client requests a set of parameters from the server using DHCP. DHCP can be implemented on networks ranging in size from residential networks to large campus networks and regional ISP networks. Many routers and residential gateways have DHCP server capability. Most residential network routers receive a unique IP address within the ISP network. Within a local network, a DHCP server assigns a local IP address to each device. DHCP services exist for networks running Internet Protocol version 4 (IPv4), as well as version 6 (IPv6). The IPv6 version of the DHCP protocol is commonly called DHCPv6.
Dynamic_Host_Configuration_Protocol - Wikipedia, the free encyclopediaThe wording here is purposefully confusing. While a packet technically refers to layer 3, it is a common misnomer for "data transmitted on a network." It is uncommon to hear someone say a frame was transmitted, simply saying packet is much more common. A switch will receive a frame with a packet inside it and transmit the frame based on the MAC address in the frame header.
A network switch (also called switching hub, bridging hub, and, by the IEEE, MAC bridge) is networking hardware that connects devices on a computer network by using packet switching to receive and forward data to the destination device. A network switch is a multiport network bridge that uses MAC addresses to forward data at the data link layer (layer 2) of the OSI model. Some switches can also forward data at the network layer (layer 3) by additionally incorporating routing functionality. Such switches are commonly known as layer-3 switches or multilayer switches.Switches for Ethernet are the most common form of network switch. The first MAC Bridge was invented in 1983 by Mark Kempf, an engineer in the Networking Advanced Development group of Digital Equipment Corporation. The first 2 port Bridge product (LANBridge 100) was introduced by that company shortly after. The company subsequently produced multi-port switches for both Ethernet and FDDI such as GigaSwitch. Digital decided to license its MAC Bridge patent in a royalty-free, non-discriminatory basis that allowed IEEE standardization. This permitted a number of other companies to produce multi-port switches, including Kalpana. Ethernet was initially a shared-access medium, but the introduction of the MAC bridge began its transformation into its most-common point-to-point form without a collision domain. Switches also exist for other types of networks including Fibre Channel, Asynchronous Transfer Mode, and InfiniBand. Unlike repeater hubs, which broadcast the same data out of each port and let the devices pick out the data addressed to them,
Network_switch - Wikipedia, the free encyclopediaCAT5e is rated at 1000 megabits per second. CAT 6a is rated for 10 gigabits per second.
Category 5 cable (Cat 5) is a twisted pair cable for computer networks. Since 2001, the variant commonly in use is the Category 5e specification (Cat 5e). The cable standard provides performance of up to 100 MHz and is suitable for most varieties of Ethernet over twisted pair up to 2.5GBASE-T but more commonly runs at 1000BASE-T (Gigabit Ethernet) speeds. Cat 5 is also used to carry other signals such as telephone and video. This cable is commonly connected using punch-down blocks and modular connectors. Most Category 5 cables are unshielded, relying on the balanced line twisted pair design and differential signaling for noise rejection.
Category_5_cable - Wikipedia, the free encyclopediaPlenum is a special material used to jacket a cable, this jacket is fire retardant and will reduce the amount of hazardous fumes in the air if the cable is subject to a fire.
Plenum cable is electrical cable that is laid in the plenum spaces of buildings. In the United States, plastics used in the construction of plenum cable are regulated under the National Fire Protection Association standard NFPA 90A: Standard for the Installation of Air Conditioning and Ventilating Systems. All materials intended for use on wire and cables to be placed in plenum spaces are designed to meet rigorous fire safety test standards in accordance with NFPA 262 and outlined in NFPA 90A. Plenum cable is required because, if nonplenum cable catches fire, it can release toxic fumes. If those fumes are released in a plenum space, they can spread throughout the building through the air circulation system.Plenum cable is jacketed with a fire-retardant plastic jacket of either a low-smoke polyvinyl chloride (PVC) or a fluorinated ethylene polymer (FEP). Polyolefin formulations, specifically based on polyethylene compounding had been developed by at least two companies in the early to mid-1990s; however, these were never commercialized, and development efforts continue in these yet-untapped product potentials. Development efforts on a non-halogen plenum compound were announced in 2007 citing new flame-retardant synergist packages that may provide an answer for a yet-underdeveloped plenum cable market outside the United States. In 2006, significant concern developed over the potential toxicity of FEP and related fluorochemicals including the process aid perfluorooctanoic acid (PFOA) or C8 such that California has proposed some of these materials as potential human carcinogens. The NFPA Technical Committee on Air Conditioning, in response to
Plenum_cable - Wikipedia, the free encyclopediaYou are a Desktop Technician in a company's IT Department. You need to find the hardware specifications of a desktop, however the device does not have an operating system installed. Which of the following options will display this information?
The BIOS (Basic Input Output System) firmware application will display information like the CPU, RAM and hard drive information. It is not necessary to have an operating system installed to utilize the BIOS.
In computing, BIOS (, BY-oss, -ohss; Basic Input/Output System, also known as the System BIOS, ROM BIOS, BIOS ROM or PC BIOS) is firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the booting process (power-on startup). The BIOS firmware comes pre-installed on an IBM PC or IBM PC compatible's system board and exists in some UEFI-based systems to maintain compatibility with operating systems that do not support UEFI native operation. The name originates from the Basic Input/Output System used in the CP/M operating system in 1975. The BIOS originally proprietary to the IBM PC has been reverse engineered by some companies (such as Phoenix Technologies) looking to create compatible systems. The interface of that original system serves as a de facto standard. The BIOS in modern PCs initializes and tests the system hardware components (Power-on self-test), and loads a boot loader from a mass storage device which then initializes a kernel. In the era of DOS, the BIOS provided BIOS interrupt calls for the keyboard, display, storage, and other input/output (I/O) devices that standardized an interface to application programs and the operating system. More recent operating systems do not use the BIOS interrupt calls after startup.Most BIOS implementations are specifically designed to work with a particular computer or motherboard model, by interfacing with various devices especially system chipset. Originally, BIOS firmware was stored in a ROM chip on the PC motherboard. In later computer systems, the BIOS contents are stored on flash
BIOS - Wikipedia, the free encyclopediaThe Hyper Text Transfer Protocol (HTTP) uses port TCP 80 by default. The encrypted version (HTTPS) uses TCP 443.
The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, where hypertext documents include hyperlinks to other resources that the user can easily access, for example by a mouse click or by tapping the screen in a web browser. Development of HTTP was initiated by Tim Berners-Lee at CERN in 1989 and summarized in a simple document describing the behavior of a client and a server using the first HTTP protocol version that was named 0.9.That first version of HTTP protocol soon evolved into a more elaborated version that was the first draft toward a far future version 1.0.Development of early HTTP Requests for Comments (RFCs) started a few years later and it was a coordinated effort by the Internet Engineering Task Force (IETF) and the World Wide Web Consortium (W3C), with work later moving to the IETF. HTTP/1 was finalized and fully documented (as version 1.0) in 1996. It evolved (as version 1.1) in 1997 and then its specifications were updated in 1999, 2014, and 2022.Its secure variant named HTTPS is used by more than 80% of websites.HTTP/2, published in 2015, provides a more efficient expression of HTTP's semantics "on the wire". It is now used by 41% of websites and supported by almost all web browsers (over 97% of users). It is also supported by major web servers over Transport Layer Security (TLS) using an
Hypertext_Transfer_Protocol - Wikipedia, the free encyclopediaYou are trying to use RDP to control a Windows computer from your office to an accountant's computer in the corporate office building. What port should be opened in the firewalls between the two locations?
Remote Desktop Protocol (RDP) uses port 3389 to communicate.
Remote Desktop Protocol (RDP) is a proprietary protocol developed by Microsoft Corporation which provides a user with a graphical interface to connect to another computer over a network connection. The user employs RDP client software for this purpose, while the other computer must run RDP server software. Clients exist for most versions of Microsoft Windows (including Windows Mobile but the support has ended), Linux (for example Remmina), Unix, macOS, iOS, Android, and other operating systems. RDP servers are built into Windows operating systems; an RDP server for Unix and OS X also exists (for example xrdp). By default, the server listens on TCP port 3389 and UDP port 3389.Microsoft currently refers to their official RDP client software as Remote Desktop Connection, formerly "Terminal Services Client". The protocol is an extension of the ITU-T T.128 application sharing protocol. Microsoft makes some specifications public on their website.
Remote_Desktop_Protocol - Wikipedia, the free encyclopediaWhich of the following network topologies provides the most redundancy to protect against network outages?
In a Mesh network topology every network node (router, switch, hub, etc) is connected to every other network node. If a connection breaks, the node can easily communicate with another through multiple existing connections. In reality this is too complex to implement in a large network, but it is still very common to see a hybrid network with several mesh style layers.
A mesh network is a local area network topology in which the infrastructure nodes (i.e. bridges, switches, and other infrastructure devices) connect directly, dynamically and non-hierarchically to as many other nodes as possible and cooperate with one another to efficiently route data to and from clients. This lack of dependency on one node allows for every node to participate in the relay of information. Mesh networks dynamically self-organize and self-configure, which can reduce installation overhead. The ability to self-configure enables dynamic distribution of workloads, particularly in the event a few nodes should fail. This in turn contributes to fault-tolerance and reduced maintenance costs.Mesh topology may be contrasted with conventional star/tree local network topologies in which the bridges/switches are directly linked to only a small subset of other bridges/switches, and the links between these infrastructure neighbours are hierarchical. While star-and-tree topologies are very well established, highly standardized and vendor-neutral, vendors of mesh network devices have not yet all agreed on common standards, and interoperability between devices from different vendors is not yet assured.
Mesh_networking - Wikipedia, the free encyclopediaVideo Graphics Array (VGA) cables use analog signals and a 15 pin connector.
Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the IBM PC compatible industry within three years. The term can now refer to the computer display standard, the 15-pin D-subminiature VGA connector, or the 640 × 480 resolution characteristic of the VGA hardware.VGA was the last IBM graphics standard to which the majority of IBM PC compatible computer manufacturers conformed, making it the lowest common denominator that virtually all post-1990 PC graphics hardware can be expected to implement.IBM intended to supersede VGA with the Extended Graphics Array (XGA) standard, but failed. Instead, VGA was adapted into many extended forms by third parties, collectively known as Super VGA, then gave way to custom graphics processing units which, in addition to their proprietary interfaces and capabilities, continue to implement common VGA graphics modes and interfaces to the present day. The VGA analog interface standard has been extended to support resolutions of up to 2048 × 1536 and even higher in special applications.
Video_Graphics_Array - Wikipedia, the free encyclopediaWhich of the following network standards can operate at two different channel widths on the same spectrum simultaneously?
Using "channel bonding" the 802.11n wireless standard is capable of operating on two separate channels at the same time. This feature allows 802.11n networks to double their bandwidth, however it can result in increases interference and power usage.
IEEE 802.11n-2009 or 802.11n is a wireless-networking standard that uses multiple antennas to increase data rates. The Wi-Fi Alliance has also retroactively labelled the technology for the standard as Wi-Fi 4. It standardized support for multiple-input multiple-output, frame aggregation, and security improvements, among other features, and can be used in the 2.4 GHz or 5 GHz frequency bands. As the first Wi-Fi standard that introduced MIMO (Multiple-Input and Multiple-Output) support, sometimes devices/systems that support 802.11n standard (or draft version of the standard) are being referred to as MIMO (Wi-Fi products), especially before the introduction of the next generation standard. The use of MIMO-OFDM (Orthogonal Frequency Division Multiplexing) to increase the data rate while maintaining the same spectrum as 802.11a was first demonstrated by Airgo Networks.The purpose of the standard is to improve network throughput over the two previous standards—802.11a and 802.11g—with a significant increase in the maximum net data rate from 54 Mbit/s to 72 Mbit/s with a single spatial stream in a 20 MHz channel, and 600 Mbit/s (slightly higher gross bit rate including for example error-correction codes, and slightly lower maximum throughput) with the use of four spatial streams at a channel width of 40 MHz.IEEE 802.11n-2009 is an amendment to the IEEE 802.11-2007 wireless-networking standard. 802.11 is a set of IEEE standards that govern wireless networking transmission methods. They are commonly used today in their 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac and 802.11ax versions to provide wireless connectivity in homes and businesses. Development of 802.11n began in 2002, seven years before publication. The 802.11n protocol is
IEEE_802.11n-2009 - Wikipedia, the free encyclopediaThermal paste (or Thermal grease) is designed to conduct heat traveling between two elements. In this case, Thermal paste allows heat to efficiently leave the processor and travel to the heat sink.
Thermal paste (also called thermal compound, thermal grease, thermal interface material (TIM), thermal gel, heat paste, heat sink compound, heat sink paste or CPU grease) is a thermally conductive (but usually electrically insulating) chemical compound, which is commonly used as an interface between heat sinks and heat sources such as high-power semiconductor devices The main role of thermal paste is to eliminate air gaps or spaces (which act as thermal insulation) from the interface area in order to maximize heat transfer and dissipation Thermal paste is an example of a thermal interface material As opposed to thermal adhesive, thermal paste does not add mechanical strength to the bond between heat source and heat sink
Thermal_grease - Wikipedia, the free encyclopediaYou are a Server Administrator at a small company. Company policy dictates that all remote connections must be encrypted and accessed using some form of authentication. Which of the following will allow a user to upload a large file from home, while adhering to company policy?
SFTP (SSH File Transfer Protocol) is a protocol for securely uploading files to a remote server. SSH alone is not enough to upload a file and is incorrect. SSH provides the encryption & authentication but does not meet the requirement to upload a file. As SFTP builds upon SSH with functionality for file upload it is the correct answer.
In computing, the SSH File Transfer Protocol (also known as Secure File Transfer Protocol or SFTP) is a network protocol that provides file access, file transfer, and file management over any reliable data stream. It was designed by the Internet Engineering Task Force (IETF) as an extension of the Secure Shell protocol (SSH) version 2.0 to provide secure file transfer capabilities. The IETF Internet Draft states that, even though this protocol is described in the context of the SSH-2 protocol, it could be used in a number of different applications, such as secure file transfer over Transport Layer Security (TLS) and transfer of management information in VPN applications. This protocol assumes that it is run over a secure channel, such as SSH, that the server has already authenticated the client, and that the identity of the client user is available to the protocol.
SSH_File_Transfer_Protocol - Wikipedia, the free encyclopediaA supervisor has asked you to update the BIOS on a customer's laptop. Where is the best place to find the correct BIOS firmware?
The best place to find any firmware or software upgrade for a device is through manufacture support. Although it may be possible to find the correct software elsewhere, the manufacture is likely to have tested each version prior to release.
In computing, BIOS (, BY-oss, -ohss; Basic Input/Output System, also known as the System BIOS, ROM BIOS, BIOS ROM or PC BIOS) is firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the booting process (power-on startup). The BIOS firmware comes pre-installed on an IBM PC or IBM PC compatible's system board and exists in some UEFI-based systems to maintain compatibility with operating systems that do not support UEFI native operation. The name originates from the Basic Input/Output System used in the CP/M operating system in 1975. The BIOS originally proprietary to the IBM PC has been reverse engineered by some companies (such as Phoenix Technologies) looking to create compatible systems. The interface of that original system serves as a de facto standard. The BIOS in modern PCs initializes and tests the system hardware components (Power-on self-test), and loads a boot loader from a mass storage device which then initializes a kernel. In the era of DOS, the BIOS provided BIOS interrupt calls for the keyboard, display, storage, and other input/output (I/O) devices that standardized an interface to application programs and the operating system. More recent operating systems do not use the BIOS interrupt calls after startup.Most BIOS implementations are specifically designed to work with a particular computer or motherboard model, by interfacing with various devices especially system chipset. Originally, BIOS firmware was stored in a ROM chip on the PC motherboard. In later computer systems, the BIOS contents are stored on flash
BIOS - Wikipedia, the free encyclopediaUEFI (Unified Extensible Firmware Interface) is the next generation of BIOS. Technically it is not a new version or upgrade of BIOS but an entirely new solution. However as it does the same job, it is commonly referred to as a BIOS.
The Unified Extensible Firmware Interface (UEFI) is a publicly available specification that defines a software interface between an operating system and platform firmware. UEFI replaces the legacy Basic Input/Output System (BIOS) firmware interface originally present in all IBM PC-compatible personal computers, with most UEFI firmware implementations providing support for legacy BIOS services. UEFI can support remote diagnostics and repair of computers, even with no operating system installed.Intel developed the original Extensible Firmware Interface (EFI) specifications. Some of the EFI's practices and data formats mirror those of Microsoft Windows. In 2005, UEFI deprecated EFI 1.10 (the final release of EFI). The Unified EFI Forum is the industry body that manages the UEFI specifications throughout.
Unified_Extensible_Firmware_Interface - Wikipedia, the free encyclopediaOf the following choices, which is an industry standard protocol used by computer networks to assign IP Addresses to network nodes and devices?
Dynamic Host Configuration Protocol (DHCP) assigns IP's to network devices. Domain Name Service (DNS) translates between IP Addresses and Domain names. Address Resolution Protocol translates between IP Addresses and MAC Addresses (Reverse-ARP, RARP does the opposite)
The Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on Internet Protocol (IP) networks for automatically assigning IP addresses and other communication parameters to devices connected to the network using a client–server architecture.The technology eliminates the need for individually configuring network devices manually, and consists of two network components, a centrally installed network DHCP server and client instances of the protocol stack on each computer or device. When connected to the network, and periodically thereafter, a client requests a set of parameters from the server using DHCP. DHCP can be implemented on networks ranging in size from residential networks to large campus networks and regional ISP networks. Many routers and residential gateways have DHCP server capability. Most residential network routers receive a unique IP address within the ISP network. Within a local network, a DHCP server assigns a local IP address to each device. DHCP services exist for networks running Internet Protocol version 4 (IPv4), as well as version 6 (IPv6). The IPv6 version of the DHCP protocol is commonly called DHCPv6.
Dynamic_Host_Configuration_Protocol - Wikipedia, the free encyclopediaTPM (Trusted Platform Module) is a standard cryptoprocessor used to store cryptographic keys
Trusted Platform Module (TPM, also known as ISO/IEC 11889) is an international standard for a secure cryptoprocessor, a dedicated microcontroller designed to secure hardware through integrated cryptographic keys. The term can also refer to a chip conforming to the standard. One of Windows 11's system requirements is TPM 2.0. Microsoft has stated that this is to help increase security against firmware attacks.
Trusted_Platform_Module - Wikipedia, the free encyclopediaA customer is explaining their PC's symptoms, but you already know what the issue is. Which is the most appropriate action?
You should always do your best not to interrupt a customer while they are speaking, unless it going to take an excessive amount of time.
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