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Definition
| provides permanent or nonvolatile storage. Using secondary storage devices such as a hard-disk drive, data and programs can be retained after the computer has been shut off. |
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Term
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Definition
| is the process of saving information to the secondary storage device |
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Definition
| is the process of accessing information from secondary storage |
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Definition
| are the actual physical material that holds the data and programs. |
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Definition
| are hardware that reads data and programs from storage media. Most also write to storage media |
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Term
| hard disk - secondary storage type |
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Definition
| use rigid metallic platters that are stacked one on top of another. Hard disks store & organize files using tracks, sectors, & cylinders |
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Definition
| is located inside the system unit. |
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Term
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Definition
| typically connect to a USB or FireWire port on the system unit & are easily removed. Like an internal hard disk, external hard disks have a fixed amount of storage. However, since each removable hard disk can be easily replaced by another removable hard disk, a single port on the system unit can provide access to an unlimited amount of storage |
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Definition
| improves hard-disk performance by anticipating data needs. It performs a function similar to cache memory |
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Term
| RAID (redundant arrays of inexpensive disks) |
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Definition
| improve performance by expanding external storage, improving access speed, & providing reliable storage. Several inexpensive hard-disk drives are connected to one another |
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Term
| Optical disc technology - secondary storage type |
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Definition
| a laser beam alters the surface of a plastic or metallic disc to represent data. (compact, high capacity, use laser technology) |
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Definition
| 1s & 0s are represented by lands (flat areas) & pits (holes) on the disc surface. |
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Term
| CD (compact disc) - optical disc type |
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Definition
| was the most widely used optical format - 0.7 Gbytes |
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Term
| ROM (read-only memory) optical disc format |
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Definition
| means it cannot be written on or erased by the user. Thus, you as a user have access only to the data imprinted by the publisher. Used to distribute large databases, software applications, and music. |
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Term
| R (recordable)/ write once - optical disc format |
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Definition
| ) can be written to once. After that it can be read many times without deterioration but cannot be written on or erased. Used to archive data, download information and music from the Internet. |
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Term
| RW (rewritable) - optical disc format |
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Definition
| erasable optical discs , these discs are very similar to CD-Rs except that the disc surface is not permanently altered when data is recorded. Because they can be changed, CD-RWs are often used to create and edit multimedia presentations. |
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Term
| DVD ( digital versatile disc) - optical disc type |
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Definition
| new standard optical disc. DVDs are very similar to CDs except that more data can be packed into the same amount of space. - 4.7 gbytes |
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Term
| Blue-ray disc (BD)/high-def - optical disc type |
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Definition
| blue-colored laser that is used to read the disc and discs are larger in capacity. 25 gbytes |
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Term
| solid state storage - secondary storage type |
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Definition
| have no moving parts. Data and information are stored and retrieved electronically directly from these devices much as they would be from conventional computer memory |
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Term
| flash memory cards - types of solid-state storage |
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Definition
| are small solid-state storage devices widely used in portable devices. Some of the cards are used within devices such as smart- phones, digital media players, and GPS navigation systems. |
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Term
| USB drives / flash drives - types of solid-state storage |
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Definition
| are so compact that they can be transported on a key ring. |
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Term
| Cloud storage/online storage - types of secondary storage |
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Definition
| Internet acts as a “cloud” of servers that supply applications to clients as a service rather than a product. server is connected to the internet |
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Definition
| (google docs, office 365, IUanywhere) |
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Term
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Definition
| are specialized high- capacity secondary storage devices designed to meet organizational demands for data |
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Term
| enterprise storage system |
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Definition
| to promote efficient and safe use of data across the networks within their organizations |
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Term
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Definition
| dedicated computers with very large storage capacities that provide users access to fast storage and retrieval of data. |
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Term
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Definition
| is a hard-disk failure that occurs when a read–write head of a hard disk drive comes in contact with its rotating platter, resulting in permanent and usually irreparable damage to the magnetic media on the platter surface. |
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Term
| twisted-pari cable / ethernet cables - physical communication channel |
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Definition
| consists of pairs of copper wire that are twisted together. Both standard telephone lines and Ethernet cables use twisted pair. (a) Slowest, (b) being phased out by more advanced and reliable media, (c) cabling standard in LANs |
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Term
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Definition
| a high-frequency transmission cable, replaces the multiple wires of telephone lines with a single solid-copper core. A coaxial cable has over 80 times the transmission capacity of twisted pair. Coaxial cable is used to deliver television signals as well as to connect computers in a network. |
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Term
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Definition
| transmits data as pulses of light through tiny tubes of glass. Fiber-optic cable has over 26,000 times the transmission capacity of twisted-pair cable. It is lighter, faster, and more reliable at transmitting data. Fiber-optic cable is rapidly replacing twisted-pair cable telephone lines. |
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Term
| wireless communication channel |
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Definition
| do not use a solid substance to connect sending and receiving devices, move data through the air. Most use radio waves. |
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Term
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Definition
| uses high-frequency radio signals to transmit data. letter of standard indicates the speed (often used at home) |
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Term
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Definition
| uses high-frequency radio waves. Line-of-sight communication-can only travel in a straight line. Transmitted only over relatively short distances. Good between close proximity buildings; longer distances require relaying |
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Term
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Definition
uses satellites orbiting about 22,000 miles above the earth as microwave relay stations. Uplink send data to the satellite; downlink receive data from the satellite
8. A network of satellites owned & managed by the Department of Defense continuously sends location information to earth |
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Term
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Definition
| devices use that information to uniquely determine the geographic location of the device. Available in many devices to provide navigational support with a monitor to display maps & speakers to provide spoken directions. |
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Term
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Definition
| uses infrared light waves to communicate over short distances. a line-of-sight communication |
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Term
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Definition
| large corporations leased special high-speed lines from telephone companies. Originally, these were copper lines (T1 lines), that could be combined to form higher-capacity options (T3 or DS3 lines). These lines have largely been replaced by faster optical carrier (OC) lines. (Medium Band) |
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Term
| DSL/Digital subscriber line |
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Definition
| is provided by existing telephone companies using phone lines to provide high-speed connections. ADSL (asymmetric digital subscriber line) is one of the most widely used types of DSL. DSL is much faster than dial-up. (Broadband) (typically 1.5 mbps or higher) |
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Term
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Definition
3G started in the 2000s & provided services capable of effective connectivity to the Internet, marking the beginning of smartphones
4G has been widely marketed by several cellular services, not everyone acknowledges that this generation has begun.
4G has entered into its infancy with providers using WiMax & LTE connections to provide faster transmission speeds |
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Term
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Definition
| is a measurement of the width or capacity of the communication channel. How much information can move across the communication channel in a given amount of time. BPS (Bits per second) |
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Term
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Definition
| set of rules for the exchange of data between computers |
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Term
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Definition
| The essential features of this protocol involve (1) identifying sending & receiving devices (using IP address and DNS) & (2) breaking information into small parts for transmission across the Internet (Packetization). |
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Term
| ip address/internet protocol address |
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Definition
| Every computer on the Internet has a unique numeric address |
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Term
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Definition
| A system was developed to automatically convert text-based addresses to numeric IP addresses. |
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Term
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Definition
| Information sent across the Internet goes through many interconnected networks. Before the message is sent, it is broken down into small parts called packets . Each packet is sent separately over the Internet. At the receiving end, the packets are reassembled |
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Term
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Definition
| a node that requests & uses resources available from other nodes. Typically, a client is a user’s microcomputer |
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Term
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Definition
| any computer system that can be accessed over a network. |
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Term
| NIC/Network Interface Cards |
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Definition
| these are expansion cards located within the system unit that connect the computer to a network (LAN adapter). |
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Term
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Definition
| . Networks with nodes that are in close physical proximity—within the same building, for instance |
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Term
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Definition
| is a device that allows one LAN to be linked to other LANs or to larger networks. |
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Term
| WLAN/wireless local area network |
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Definition
| A wireless local area network |
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Term
| wireless access point/ base station |
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Definition
| This access point interprets incoming radio frequencies & routes communications to the appropriate devices. |
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Term
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Definition
| Wireless access points that provide Internet access are widely available in public places |
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Term
| PAN / personal area network |
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Definition
| is a type of wireless network that works within a very small area—your immediate surroundings. PANs connect cell phones to headsets, PDAs to other PDAs, keyboards to cell phones, ect (ie ipad & iphone sync when they get close) |
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Term
| MAN / Metropolitan area network |
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Definition
| MANs span distances up to 100 miles. These networks are frequently used as links between office buildings that are located throughout a city. |
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Term
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Definition
| are countrywide and worldwide networks. These networks provide access to regional service (MAN) providers and typically span distances greater than 100 miles. They use microwave relays and satellites to reach users over long distances—for example, from Los Angeles to Paris. Of course, the widest of all WANs is the Internet, which spans the entire globe. |
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Term
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Definition
| or way of coordinating the sharing of information and resources. |
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Term
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Definition
| use central computers to coordinate and supply services to other nodes on the net- work. The server provides access to resources such as web pages, databases, application software, and hardware. |
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Term
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Definition
| nodes have equal authority and can act as both clients and servers. |
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Term
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Definition
| is a private network within an organization that resembles the Internet. Like the public Internet, intranets use browsers, websites, & web pages. |
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Term
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Definition
| is a private network that connects more than one organization. Many organizations use Internet technologies to allow suppliers & others limited access to their networks. The purpose is to increase efficiency & reduce costs. |
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Term
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Definition
| consists of hardware and software that control access to a company’s intranet and other internal networks. Guard against unauthorized access (extern threats). |
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Term
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Definition
| All communications between the company’s internal networks and the outside world pass through this server. By evaluating the source and the content of each communication, the proxy server decides whether it is safe to let a particular message or file pass into or out of the organization’s network. Gatekeeper to the network. |
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Term
| VPN - virtual private networks |
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Definition
| create a secure private connection between a remote user and an organization’s internal network. Special VPN protocols create the equivalent of a dedicated line between a user’s home or notebook computer and a company server. The connection is heavily encrypted, and, from the perspective of the user, it appears that the workstation is actually located on the corporate network. |
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Term
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Definition
| Internet service for uploading and downloading files. |
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