Local area networks Flashcards
what is a network?
computing devices connected with communications channel to share hardware and software resources.
what is a transmission medium?
cables/WiFi point makes transmission possible bounded or unbounded(wireless)
what is LAN?
network capabilities of group of computers near each other to share resources connected to LANs WANs and internet
what are network interface cards
to which network media can connect
what is bounded meia?
cables used as network transmission medium to carry signals between computer and peripherals.
what is bounded medium?
signals confined to medium and don’t leave.
what is bandwidth?
theoretical maximum amount of data travels along cable per unit time.
what is a twisted pair cable?
insulated strands of copper wire twisted around each other.
what do twisted pair cable prevent
electrical interference from adjacent pairs or outside sources.
what is an unshieled twisted pair cable?
several pairs copper cables covered in plastic.
why are UTPs widely used?
easy to install,expand and troubleshoot.
what are UTPs advantages and disadvantages?
cost of cabling is relatively low.
they are easy to install with simpler connections
length can’t be greater than 100 meters.
copper cables have inherent weakness.
what are copper cable weaknesses?
eavesdropping signals can be intercepted by outsiders.
Attenuation signal loses strength over distance
Crosstalk signals from 1 line interfere with signals from another line
Electromagnetic interference signals from nearby sources corrupt signal travelling.
why are fibre optic cables different?
optical fibres carry digital data singals in light pulses which means no electric impulses to steal
what do they consist of
consists of thin glass cylindrical core covered by cladding
what happens when the fibres are made from plastic?
they are easier to install but are unable to carry light pulses for long distances
what is multimode fibre?
larger core used for shorter distances.
what is single mode fibre?
smaller core for longer distances.
what are the advantages and disadvantages?
data trasmitted at high speeds
transmitted over long distance securely
used to connect segments of LAN. more expesnsive than UTP and requites experise to properly install and connect devices.
what does wireless mean?
consists of radio and microwave communication,light,visble and infrared
what is bluetooth?
wireless technology to send data over short distances and it handles data or voice transmissions at same time using little power.
what is near field communication(NFC)
wireless connection between 2 device in close proximity and it is Two-way communication and sends and receives information.
what are Radio waves?
Electromagnetic wave used in communication and data transfer. long wavelengths in Em spectrum and frequency determines distance transmitted.
what are transmission technologies?
point to point and broadcast