Buscar
Estás en modo de exploración. debe iniciar sesión para usar MEMORY

   Inicia sesión para empezar

level: Lecture 3

Questions and Answers List

Wired Transmission.

level questions: Lecture 3

QuestionAnswer
Three main type of network cables:Coaxial. Twisted pair. (un-shielded and shielded). Fibre optics.
Bandwidth.Maximum data rate transfer possible.
Throughput.The actual data transfer rate; less than or equal to bandwidth.
Electromagnetic Interference (EMI):Caused by the presence of electrical and/or magnetic signals.
Radio Frequency Interference (RFI):Caused by the presence of radio signals.
Attenuation:Signal loss caused by degradation of signal over distance.
Characteristics of Copper Wire.Soft, malleable, ductile metal. Very high thermal and electric conductivity. Conductor of heat and electricity. Data transmitted as ANALOG.
Two types of copper wire:Coaxial. Twisted Pair.
What is/Characteristics of a coaxial cable?Thick copper wire surrounded by three layers.
Three layers surrounding the copper wire of a coaxial cable?- Plastic Jacket. - Braided shield. - Plastic (PVC or Teflon).
The layers of a coaxial cable help to reduce:Electromagnetic Interference (EMI) and Radio Frequency Interference (RFI).
Characteristic of Thin Ethernet "Thinnet".10 base 2. 10 mbps. Baseband. 185m. 5mm or 2/10" diameter, Radio-Grade 58(RG58). 30 nodes per segment.
Characteristics of a Thick Ethernet "Thicknet"10 base 5. 10 mbps. Baseband. 500m. 1/2" diameter, Radio-Grade 8(RG8). 1024 nodes per segment.
Two types of Coaxial Connectors:F-Type Connector (75 OHM). BNC Connector (50 OHM).
These describe how data is transmitted between two nodes.Baseband. Broadband.
BasebandBaseband Technology transmits a singles data signal/stream/channel at a time.
BroadbandBroadband Technology transmits multiple data signals/streams/channels simultaneously at the same time.
Two types of Twisted Pair Cables:Un-shielded twisted pair.(UTP) Shielded twisted pair.(STP)
The current Twisted Pair Categories:Cat 5: 100MHz/2 pairs; 100 mbps (100 base TX). Cat 5e: 100MHz/4 pairs; 1,000 mbps (1000 base T). Cat 6: 250MHz/2pairs; 1,000 mbps (1000 base TX). Cat 6a: 500MHz/4 pairs; 10,000 mbps (10G base T).
Carrier sense multiple access with collision detect.- Nodes listens to wire. - Node transmits data. - If another transmission data, there is collision. - Nodes send a jam signal and wait using the back-off algorithm.
Two types of fibre-optic cables:Multi-mode fibre (MMF). Single-mode fibre (SMF).
Fibre Optic Cables.Flexible, transparent, strand of glass (silica) or plastic slightly thicker than a human hair. It allows longer distances and higher bandwidths than copper cables. Data is transmitted as DIGITAL.
Fibre-Optic Characteristics.Glass or plastic core (distance vs cost) surrounded by glass or plastic cladding, plastic, amour coating, (usually Kevlar) and PVC or Teflon.
Fibre Optic Connectors egs:Straight Tip (ST), Local Connector (LC), Square Connector(SC).
Total distance of a twisted pair cable:100m
Total distance of a Thinnet cable:185m
Total distance of a Thicknet cable?500m
Total distance of a multi-mode fibre cable:1000m/1km
Total distance of a single-mode fibre cable:50km