Coaxial Cable CableTV and Internet access

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Coaxial CableCableTV and Internet access

• Highly resistant to noise
• Span longer distances
• More expensive
• Lower throughput
• Not as physically flexible

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Copper Cable - Non-twisted Wire

• Quad wire
• Traditional dual telephone cable
• Span short distances
• Low resistance to noise
• Inexpensive
• Low throughput
• Sufficient for analog/voice
• Not installed anymore

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Twisted Pair (TP)

• 1-4200 pairs of wire
• 2 pairs Dual telephone cable after 1980s
• Twists reduce the effect of crosstalk
• Span short distances, Inexpensive, Flexible, easy
  to install, Fast transmission rates
• Susceptible to physical damage
• 2 types Unshielded (UTP) and Shielded (STP)

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Shielded Twisted Pair (STP)

• Foil/metal shielding acts as an external barrier
  to electromagnetic forces.
• Then coated in plastic sheath.
• More expensive
• Less Flexible
• Same transmission capacity as UTP

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Unshielded Twisted Pair (UTP)

• Encased only in the external plastic sheath
• Less expensive and
• Less resistant to noise
• Comes in different Categories
• CAT3 Telephone
• CAT5/e LANs

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Fiber Optic Cable

• Light experiences little resistance
• Able to transmitted at faster rates
• Unaffected by electromagnetic interference
• Cable is designed to reflect light and travel
  distances
• Signal weakening is optical loss
• Refraction and Absorption can cause attenuation,
  distortion and loss

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Fiber Optic Cable
Narrow core High Bandwidth Long distances
Larger diameter core Multiple pulse angles give
multiple channels High Bandwidth Shorter
distances - attenuation
High Cost Complex installation Simplex mode
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Popular Uses for Fiber Optic Cable

• Includes connecting
• Regional and local cable TV facilities
• Internet ISPs connecting to other large
  communications exchange points
• Central offices with other central offices
• Main feeders with central offices
• A telecommunications network with private LANs
• A telecommunications network with private
  switching systems, such as PBX

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Selecting Appropriate Media

• When selecting telecommunications media consider
• Existing infrastructure
• Throughput potential
• Cost of installation
• Noise immunity
• Security
• Size and scalability

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Comparison of Physical Media
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