The importance of cable
- Fundamental to network communication
- Incredibly important foundation
- Usually only get one good opportunity at architecting your cabling infrastructure
- Make it good!
- The vast majority of wireless communication uses cables
- Unless you're an amateur radio operator!
- Transmission by light
- The visible spectrum
- No RF signal
- Very difficult to monitor or tap
- Signal slow to degrade
- Transmission over long distances
- Immune to radio interference
- There's no RF
- Short-range communication
- Up to 2 km
- Inexpensive light source
- i.e., LED
- Long-range communication
- Up to 100km without processing
- Expensive light source
- Laser beams
- Balanced pair operation
- Two wires with equal and opposite signals
- Transmit+. Transmit- / Receive+, Receive-
- The twist is the secret!
- Keeps a single wire constantly moving away from the interference
- The opposite signals are compared on the other end
- Pairs in the same cable have different twist rates
Shielded and unshielded cable
- STP (Shielded Twisted Pair)
- Additional shielding protects against interference
- Requires the use of an electrical ground
- Max distance follows the Ethernet standard
- UTP (Unshielded Twisted Pair)
- No additional shielding
- The most common twister pair cabling
- Max distance follows the Ethernet standard
Plenum-rated cable
- Cable jacket
- Polyvinyl chloride (PVC) or fluorinated ethylene polymer (FEP)
- Plenum-rated cable may not be flexible
- May not have the same bend radius
- Worst-case planning
- Important concerns for any structure
- The riser
- Between-floor connections use riser cable
- Riser cable fire requirements aren't as strict as plenum cable
- Two or more forms share a common axis
- Used in older Ethernet networks
- 10BASES "Thicknet" RG-8/U (500m), 10BASE2 "Thinnet" RG-58 (185m)
- Used in television/digital cable
- Broadband internet
- RG-56
- Short distance video
- RG-59
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