Communications and Networks Part 1 Flashcards
Analog data can be represented as a _____.
wave
[Explanation]
Analog data is measured in ranges. If using the analogy of a light switch, a light dimmer switch would be analog and a normal on/off switch would be digital.
Telephone lines have traditionally been analog.
______ data is data that has been converted into discrete digits such as 0s and 1s.
Digital
[Explanation]
Data includes text, numbers, graphics, sound and video. The 1s and 0s used to represent digital data are known as binary digits.
A _____ takes digital signals from a computer and converts them to analog signals to transmit over a telephone line.
modem
[Explanation]
A modem is a device that sends and receives data over telephone lines to and from computers. Telephone (dial up) modems provide narrowband or low bandwidth internet connections. A telephone modem is still the cheapest way to connect to the internet and such connections are available everywhere.
A system of interconnected telephones, computers, or other communication devices that can communicate and share data is called a _______.
network
[Explanation]
Networks can be wired or wireless. An advantage of a network is that it allows for the sharing of peripheral devices; users on a network can share devices such as printers and modems.
A data communications network that connects personal computers within a limited geographical area is called a ___.
LAN
[Explanation]
A LAN (Local Area Network) normally occupies a single building. Home networks and school computer labs are examples of LANs.
A communications network that covers a large geographic area such as a country is called a _____.
WAN
[Explanation]
The internet is an example of a WAN (Wide Area Network). It connects many LANs (local area networks) and allows computers to communicate with other computers that are far away.
What does LAN stand for?
Local Area Network
What does WAN stand for?
Wide Area Network
In a _____________ LAN, individual computer users share the services of a centralized computer.
client/server
Individual computers (PCs, workstations) are called clients and the centralized computer is called a _____.
server
In a ___________ network, workstations share responsibility for processing, storage, printing, and communications tasks without a server.
peer to peer
[Explanation]
Examples of popular file sharing networks which operate in peer to peer mode include BitTorrent and Napster.
A ____ server is a centralized computer that acts like a disk drive, storing programs and data shared by users on the LAN.
file
A _____ server manages one or more printers and stores printed images.
An organization’s internal private network is called an ________.
intranet
[Explanation]
One use of an intranet is to allow employees to access and exchange company data needed to do their jobs.
Private intranets that connect internal personnel and selected vendors are called ________.
extranets
[Explanation]
An example of an extranet would be an intranet that connects a car manufacturer with their dealers.
Private networks that are connected to remote sites via the _______ are called VPNs.
internet
What does VPN stand for?
VPN stands for Virtual Private Network
A ________ is a set of rules governing the exchange of data between hardware and software on a communications network.
protocol
[Explanation]
TCP/IP is an example of a network communications protocol.
Each connection point on a network is called a ____.
node
[Explanation]
Network nodes include computers, network devices, and networked peripherals.
A hub is a commonly used component that ______ devices on the LAN.
connects
[Explanation]
Hubs have multiple ports. When a packet arrives at one port it is copied to all other ports on the hub.
Unlike a hub, a ______ sends packets only to the computer that is the intended recipient.
switch
[Explanation]
Like hubs, switches have multiple ports. The difference is that with a switch, when a packet arrives, it is copied only to the port that leads to the intended recipient, whereas a hub blasts out the packet to all of its ports.
________ are used to transmit data between LANs of different network topologies or network operating systems.
Gateways
A (___) is used by a computer to transmit and receive data over a network.
NIC
What does NIC stand for?
Network interface card
___, ring, and star are the three basic network topologies.
Bus
A bus network has two endpoints and all computers are connected to a single wire or _____.
cable
[Explanation]
Data packets on a bus can collide; when this happens, the sending device waits and retransmits. If a connection on the bus is broken (i.e. one of the computers in the chain crashes), the network may go down.
A ___ network has no endpoints and all computers are connected in a continuous loop.
ring
[Explanation]
In a ring network, all packets flow in only one direction; there are no data collisions. If a connection on the ring is broken, the network may go down.
In a star network, all computers are connected to a _______ computer.
central
[Explanation]
The central computer is called a hub. The hub prevents packet collisions, but if the hub goes down the network stops.
____ is a set of special instructions used to create web pages.
HTML
What does HTML stand for?
Hypertext Markup Language
What are HTML (Hypertext Markup Language) tags used for?
To structure and format web pages and links to other documents.
__________ appear as colored or underlined words on a webpage.
Hyperlinks
[Explanation]
Using the mouse to click on hyperlinked text connects the user to another web page or a different location on the current web page.
A ____ is one or more web documents that can be viewed and changed by users.
A wiki
[Explanation]
This is where the term wikipedia (a group edited encyclopedia) comes from.
An organization that provides _______________ is called an ISP.
internet access
[Explanation]
EarthLink, AT&T, and Road Runner are all examples of ISPs (Internet Service Provider).
What does ISP stand for?
Internet Service Provider
The internet backbone consists of high speed, high capacity transmission lines that use the newest communications technology to ______ data across the internet.
transmit
[Explanation]
Backbone connections are supplied by internet backbone providers such as GTE, Sprint, UUNET and AT&T.
_________ is an expression of how much data can be sent through a communications channel in a given amount of time.
Bandwidth
[Explanation]
Data includes text, voice, and video. The bandwidth of a channel which carries digital data is typically measured in bits per second (bps).
