Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/27

Click to flip

27 Cards in this Set

  • Front
  • Back
What are computer Networks used for?
Used to link computers locally or to the internet
What are four types of network media?
Twisted-Pair Wire
Coaxial Cable
Fiber-Optic Cable
Wireless Links
What are Twisted-Pair Wires?
-was orginally standard telephone wire
-consited of two copper strands, individually wrapped in plastic, and then twisteed together, and bound together in another layer of plastic insulation
-able to carry signals up to 100Mbps
-does not protect data from electromagnetic interference
What are Coaxial Cables?
-used for cable TV
-contains two conductors: one is a single wire int he centre of the cable, and the other wire is a wiremesh shield that surrounds the central wire, with an insulator in between.
-able to carry more data than older twisted-pair wiring
-wire mesh shields against interference
-can carry data up to 10 mbps (slow compared to newer twistedpair and fiber-optic wiring)
What are Fiber-optic Cables?
-think strand of glass that transmit pulsating beams of light
-light is carried from one end to the other
- a disadvantage is that it cannot turn sharp corners
- transfer rate is up to 500 Mbps
- not affected by electromagnetic interference
What are three wireless links?
Infrared, radio waves, communications satelites
What are infrared light waves used for?
Used to transmit data a few metres -> wireless keyboards, mice, printers
What are Radio Waves used for?
companies can transmit inventory data from each store to a central computer
what are communications satellites used for?
-used when data must be transported thousands of miles
-large businesses, universities, and governments use for data communication
what is a computer network?
defined as a way to connect computers together so that they are aware of each other and pool resources together
what is a network interface card?
cards used to connect various computers in a network
-fits into expansion slot
what is a router (hub)?
a common point of connection for computers and devices in a network
what are bridges and gateways?
hardware devices that can pass messages between networks
what are three networking advantages?
1. sharing peripheral devices (hardware)
2. Simultaneous access and easier backup (software)
3. Communication (people)
Explain why sharing peripheral devices is an advantage
-can share infrequently used devices (scanners, cd writers, back up devices)
-allows for jusitication of the cost of expensive devices (color laser printer)
- sharing is easy within a network
Explain why why Simultaneous access and easier back up is an advantage
-saves money by using networked version of software (saves time and storage)
-ensures data integrity
-backing up data is easier
Explain why Communication is an advantage.
-email
-effient and inexpensive
-real time
What are some types of networks?
-Local Area network (LAN)
-Metropolitan Area Network (MAN)
-Wide Area Network (WAN)
-Client-Server Relationship
-Peer-to-Peercomputing
What are LANs?
Local Area Networks are:
-a network of computers that are relatively close to each ther and connected by a contiguous wire
-usually within a single room, building, or group of adjacent buildings
-can share hardware and software
What are WANS?
wide area networks are:
-compromised of two ore more lans connected over a wider area
-may connect a number of lans in several different cities
-LANS can be connected using fiber-optic backbones, or satellite uplinks and downlinks
Client-Server Relationships?
generally, there is a server node that is used to satisfy the requests of each of the other notes in the network. the server is designated as a file server, compute server, or databse server

-in a database network, the databse server program runs one note in the network, the other noteds send requests to the server which sends data back as requested
What are four types of Network topologies?
1. Linear Bus
2. Star
3. Ring
4. Hybrid topologies
What is a linear bus topology?
-network nods send data along a common corridor
-if a collision happens, the node waits a small, random amount of time before retransmission
What is a Star topology?
-nodes are arranged around a central hub (precents collision by acting as a traffic cop) data packets are routed through the central hub to destination
-if hub goes down, network goes down too
what is a ring topology?
-nodes are connected in a circular chain
- each node examines data that is sent through the rin, but only accepts data that is addressed to it
- no danger of collision
- if one node goes down, the whole network goes down
what is a hybrid topology?
- the linear bus, star, and ring can be combined to make a hybrid network
What are network protocols?
-set of rules or language that is used to communicate data
-ethernet is most common network protocol
-there is also Token ring and ARCNET