Computer Communications – Information Technology Test
The key terms of Information Technology Test include, Computer, Communications, Data, Connected, Microcomputers.
backbone
consists of the main highway – including gateways, routers, and other communications equipment – that connects all computer networks in an organization.
topology
the logical layout, or shape, of a network.
bus network
a network in which all nodes are connected to a single wire or cable, the bus, which has two endpoints. Each communications device on the network transmits electronic messages to other devices.
ring network
a network in which all microcomputers and other communications devices are connected in a continuous loop.
star network
a network in which all microcomputers and other communications devices are directly connected to a central server.
Ethernet
a LAN technology that can be used with almost any kind of computer and that describes how data can be sent in packets in between computers and other networked devices usually in close proximity.
parity bit
also called a check bit; an extra bit attached to the end of a byte.
Unicode
Binary coding scheme that uses 2 bytes (16 bits) for each character, rather than 1 byte (8 bits). Why it’s important: Instead of the 256 character combinations of ASCII, Unicode can handle 65,536 character combinations. Thus, it allows almost all the written languages of the world to be represented using a single character set.
word size
Number of bits that the processor may process at any one time. Why it’s important: The more bits in a word, the faster the computer. A 32-bit computer ⎯that is, one with a 32-bit-word processor ⎯will transfer data within each microprocessor chip in 32-bit chunks, or 4 bytes at a time. A 64-bit computer transfers data in 64-bit chunks, or 8 bytes at at time.
UPS
uninterrupted power supply
buses (or) bus lines
electrical data roadways through which bits are transmitted within the CPU and between the CPU and other components of the motherboard.
registers
special high speed storage areas that temporarily store data during transfer processing
astable
of or relating to a system or electric circuit that oscillates spontaneously between unstable states.
monostable
(of an electronic circuit) having only one stable state but able to pass into a second state in response to an input pulse
bistable
(of a system) having two stable states.
input hardware
devices that translate data into a form the computer can process.
output hardware
devices that translate information processed by the computer into a form that humans can understand.
hardware: 3 Types
keyboards, pointing devices, and source data entry devices.
dumb terminal
video display terminal or VDT has a display sceen and a keyboard and can input and output but cannot process data.
intelligent terminal
has its own memory and processor, as well as a display screen and keyboard
internet terminal
provides access to the internet
pointing devices
control the postion of the cursor or pointer on the screen and allow the user to select options displayed on the screen.
dpi
dots per inch
analog
continuously varying in strength and/or quality-fluctuating, evolving, or continually changing.
modem
short for “modulate/demodulate.” a sending modem modulates digital signals into analog signals for transmission over phone lines. A recieving modem demodulates the analog signals back into digital signals.
network
a system of interconnected computers, telephones, or other communications devices that can communicate with one another and share applications and data.
WAN
a wide area network is a communications network that covers a wide geographic area, such as a country or the world.
MAN
a metropolitan area network is a communications network covering a city or suburb.
LAN
a local area network, or local net, connects computers and devices in a limited geographic area, such as one office, one building, or a group of buildings.
HAN
a home area network uses wired, cable, or wireless connections to link a household’s digital devices.
PAN
a personal area network uses short-range wireless technology to connect an individual’s personal electronics.
home automations network
this network relies on very inexpensive, very short-range, low-power wireless technology in the under-200-Kpbs range to link switches and sensors around the house.
client/server network
a network that consists of clients, which are microcomputers that request data, and servers, which are computers used to supply data.
peer-to-peer network
a network in which all microcomputers on the network communicate directly with one another without relying on a server.
intranet
an organization’s internal private network that uses the infrastructure and standards of the internet and the web.
extranet
a private intranet that connects not only internal personnal but also selected suppliers and other stategic parties.
VPN (or) virtual private network
a private network that uses a public network, (usually the internet) to connect remote sites.
host computer
a mainframe or midsize central computer that controls the network.
node
any device that is attached to a network-for example, a microcomputer, terminal, storage device, or printer.
packet
a fixed length block of data for transmission.
protocol (or) communications protocol
a set of conventions governing the exchange of data between hardware and/or software components in a communications network.
hub
a common connection point for devices in a network- a place of convergence where data arrives from one or more directions and is forwarded out in one or more other directions.
switch
a device that connects computers to a network
bridge
an interface used to connect the same types of networks.
gateway
an interface permitting communication between dissimilar networks.
router
a special computer that directs communicating messages when several networks are connected together.
backbone
consists of the main highway – including gateways, routers, and other communications equipment – that connects all computer networks in an organization.
topology
the logical layout, or shape, of a network.
bus network
a network in which all nodes are connected to a single wire or cable, the bus, which has two endpoints. Each communications device on the network transmits electronic messages to other devices.
ring network
a network in which all microcomputers and other communications devices are connected in a continuous loop.
star network
a network in which all microcomputers and other communications devices are directly connected to a central server.
Ethernet
a LAN technology that can be used with almost any kind of computer and that describes how data can be sent in packets in between computers and other networked devices usually in close proximity.