Guided

 Copper
  Linear Paired lines 
    Very short distances - flat phone cable. 10 feet. 24 kHz.
    + very cheap
    - highly susceptible to external (EMI) interference. 

  Twisted pair (wikipedia topic : twisted pair )- 
    Phone line to house, local area networks.  1 Mbit/sec 
      For short distances (50 feet) - 10 Mbit/sec or even 100 Mbit/sec
    - more costly. Tighter the twist, the more the cost.
    + better resistance to externally induced interference.

    Tend to be sensitive to RFI, EMI, and attenuation.

    Often built with additional shielding.

    Newer cabling (cat 5 or 6) increases twists and adds more shielding.

    + Cheap and physically very flexible. 
    - Not useful for extremely high frequencies. 
    - Distances limited without repeating/boosting.

  Cat cable used for Ethernet. Tentative figures.
    Cat 3, 10 Mib(bit)/s, 1 pair of wires, 100 meters. (unshielded)
    Cat 5, 100 MHz, 100 Mib/s, 2 pair, 100 meters max. tighter twists. 
      (unshielded)
    Cat 5e, 100 MHz, 1 Gib/s, 4 pair, 100 meters max., 
      extra shielding between pairs. Uses multiple pairs to deliver throughput.
      # For Gib/s, uses all 4 pairs and multi-level signal 3-bit/transfer
    Cat 6, 250 MHz, 10GBase-T, 37-55 meters. 
       used for 1Gib Ethernet., 4 pair, even tighter twists. 
    Cat 6e, better noise protection.
    Cat 6a, 500 MHz. *replacement for HDMI, 10GBase-T Ethernet. short distances?
      Uses multiple lines for higher throughput. 100 meters.
    Cat 7, 600 MHz, 10GBase-T Ethernet, 100 meters.
    
      en.wikipedia.org/wiki/Copper_cable_certification
      www.ni.com/product-documentation/13724/en/
      customcable.ca/cat5-vs-cat6/
      www.cableorganizer.com/articles/cat5-cat5e-cat6.htm

  Coaxial - shielded cable - up to 45 Mbits/sec.
      Before Cat5/6, was best option for higher speeds.



    100s of ft.
    Good EMI protection.
    Also better security. 

    Large (1/4") and stiff.
  
    Used when fiber optics deemed too expensive.
      Short (less than a mile) runs.
      Data throughput not as high as fiber.
      Multiple splices/taps practical.     
      Consumer connections.

    Shield acts as both guard and signal ground.

    Resistant to external corruption.

    Also, protects signal from passive theft.

    Cable for television.

    Variations : 
      Triaxial - studio camera feeds.

      Leaky feeder - shielding slotted and acts as an antenna in 
        closed quarters.

      Twinaxial or twiax has 2 data lines in the core. 
        IBM terminal and mini-computer systems. 
        10Gib networking, short runs where fiber too costly. 
        Scaled down version used for SATA-3 drive connections.


Optical (fiber)-  very high speeds > 100 Mbit ranges.
  Much lower attenuation, immune to RFI and EMI.

  Small and lightweight.

  However, fragile and requires highly skilled technicians.
    More expensive (but at multi-Gb speeds, costs break even or better)

  Long runs cheap, branching adds cost.
    Point to point. Switching or tapping 
      requires signal to be converted to electrical
      and back after switch or tap.

  Multi-mode - can carry several different light signals.
    10 Mib/s to 10 Gib/s

    Cable large diameter and more expensive.

    Interface with switches and other electronics easier and cheaper 
      than single mode.    Both switches and splicing technique.

    Lower frequency lasers mean lower bandwidth.

    Light rays can bounce off sides of fiber causing dispersion (attenuation)
      limiting the length of path before repeater required.
      
    Repeater needed at close intervals, 
      Shorter distances at higher transmission rates.
      100 Mib/s bit ~ 2 Km
      1 Gib/s ~ 1 Km   
      10 Gib/s ~ 500 meters.
  
    Backbone within a building or Gigabit to station.

    * generally orange or aqua colored jacket.

  Single-mode - carries single light signal.
    Multiple frequencies can be transmitted.

    Cable smaller and cheaper. 

    Higher frequency laser 'aimed' down center of fiber,
      allowing much greater distances without distortion.

    Interface with switches and other electronics more difficult and
      expensive (higher frequency?).

    Repeater at farther intervals, 10 miles common.
       10Gbit at 60KM possible.

    Between building, or cities.

    * yellow jacket.
 
  www.fiber-optics.info