1. Thinnet (10Base2) Characteristics (cont.): Size and scalability
Allows a maximum of 185 m per network segment (see Figure 4-20)
Noise immunity
More resistant than twisted-pair wiring
Less resistant Thicknet
Figure 4-19: Thinnet BNC connectors

2. Thinnet (10Base2) Signal bounce
Caused by improper termination on a bus network
Travels endlessly between two ends of network
Prevents new signals from getting through
Figure 4-20: A 10Base2 Ethernet network

3. Twisted-Pair (TP) Cable
Color-coded pairs of insulated copper wires twisted around each other and encased in plastic coating
Twists in wire help reduce effects of crosstalk
Number of twists per meter or foot known as twist ratio
Alien Crosstalk
When signals from adjacent cables interfere with another cable’s transmission
Figure 21: Twisted-pair cable

4. Shielded Twisted-Pair (STP)
STP cable consists of twisted wire pairs that are individually insulated and surrounded by shielding made of metallic substance
Figure 4-22: STP cable

5. Unshielded Twisted-Pair
Consists of one or more insulated wire pairs encased in a plastic sheath
Does not contain additional shielding
Figure 4-23: UTP cable

6. Unshielded Twisted-Pair
To manage network cabling, it is necessary to be familiar with standards used on modern networks, particularly Category 3 (CAT3) and Category 5 (CAT5)
Figure 4-24: A CAT5 UTP cable

7. Unshielded Twisted-Pair
CAT1 – 2 wire pairs; suitable for voice only
CAT2 – 4 wire pairs; up to 4 Mbps throughput
CAT3 – 4 wire pairs; up to 10 Mbps and 16 Mhz signal
CAT4 – 4 wire pairs; up to 10 Mbps
CAT5 – 4 wire pairs; up to 100 Mbps and 100 Mhz signal
CAT5e – up to 200 Mhz signal
CAT6 – additional foil insulation; 6x throughput than CAT5
CAT7 – unfinished standard – up to 1Ghz

8. 10BaseT
Popular Ethernet networking standard that replaced 10Base2 and 10Base5 technologies
“T” for twisted pair
Figure 4-25: A 10BaseT Ethernet network

9. 10BaseT Enterprise-wide network Spans entire organization
Often services needs of many diverse users
Figure 4-26: Interconnected 10BaseT segments

10. 100BaseT Enables LANs to run at 100-Mbps data transfer rate
Also known as Fast Ethernet
Two 100BaseT specifications have competed for popularity as organizations move to 100-Mbps technology:
100BaseTX
100BaseT4 (can use CAT3 cabling)

11. 100BaseVG Cousin of Ethernet 100 Mbps technologies
VG stands for voice grade
Also called 100VG-AnyLAN
Originally developed by Hewlett-Packard and AT&T
Now governed by IEEE standard
Requires more sophisticated NICs and can reduce network performance

12. Comparing STP and UTP Throughput Cost Connector Noise immunity
Both can transmit up to 100 Mbps
Cost
Typically, STP is more expensive
Connector
Both use RJ-45 connectors and data jacks
Noise immunity
STP is more noise-resistant
Size and scalability
Maximum segment length for both is 100 meters

13. Fiber-Optic Cable Contains one or several glass fibers at its core
Surrounding the fibers is a layer of glass called cladding
Figure 4-28: A fiber-optic cable

14. Figure 4-29: Single-mode and multimode fiber-optic cables
Single-mode fiber
Carries light pulses along single path
Multimode fiber
Many pulses of light generated by LED travel at different angles
Figure 4-29: Single-mode and multimode fiber-optic cables

15. Fiber-Optic Cable Throughput Cost Connector
Reliable in transmitting up to 1 gigabit per second
Cost
Most expensive type of cable
Connector
You can use any of 10 different types of connectors

16. Fiber-Optic Cable Two popular connectors used with fiber-optic cable:
ST connectors
SC connectors
Figure 4-30: ST and SC fiber connectors

17. Fiber-Optic Cable Noise immunity Size and scalability
Unaffected by either EMI or RFI
Size and scalability
Network segments made from fiber can span 100 meters
Signals transmitted over fiber can experience optical loss

18. 10BaseF and 100BaseFX 10BaseF 100BaseFX
Physical layer standard for networks specifying baseband transmission, multimode fiber cabling, and 10-Mbps throughput
100BaseFX
Physical layer standard for networks specifying baseband transmission, multimode fiber cabling, and 100-Mbps throughput

19. Physical Layer Networking Standards
Table 4-3: Physical layer networking standards

20. Cable Design and Management
1991 – TIA/EIA released its joint 568 Commercial Building Wiring Standard
TIA – Telecommunication Industry Assoc.
EIA – Electronic Industries Assoc.
T568A
T568B

21. Cable Design and Management
Cable plant
Hardware comprising enterprise-wide cabling system
Structured cabling
Method for uniform, enterprise-wide, multivendor cabling systems
Figure 4-31: TIA/EIA structured cabling subsystems

22. Cable Design and Management
Entrance facilities
Backbone wiring
Backbone cabling that provides vertical connections between floors of a building are called risers
Table 4-4: TIA/EIA specifications for backbone cabling

23. Cable Design and Management
Equipment room
Telecommunication closet
Punch-down block is a panel of data receptors
Patch panel is a wall-mounted panel of data receptors
Figure 4-32: Patch panel (left) and punch-down block (right)

24. Cable Design and Management
Horizontal wiring
Max distance is 100m
Figure 4-33: Horizontal wiring

25. Cable Design and Management
Work area
Patch cable is a relatively short section of twisted-pair cabling with connectors on both ends that connect network devices to data outlets
Figure 4-34: Standard TIA/EIA wall jack

26. Cable Design and Management
Figure 4-35: A structured cabling hierarchy

27. Figure 4-36: A typical UTP cabling installation
Installing Cable
Figure 4-36: A typical UTP cabling installation

28. Table 4-5: Pin numbers and color codes for an RJ-45 connector
Installing Cable
* T568A Standard
Table 4-5: Pin numbers and color codes for an RJ-45 connector

29. Figure 4-37: RJ-45 terminations on a crossover
Installing Cable
Straight-through cable
Terminations at both ends are identical
Crossover cable
Terminations locations of transmit and receiver wires on one end of cable are reversed
Figure 4-37: RJ-45 terminations on a crossover

30. Installing Cable
Do not untwist twisted-pair cables more than one-half inch before inserting them
Do not strip off more than one inch of insulation from copper wire in twisted-pair cables
Watch bend radius limitations for cable being installed
Test each segment of cabling with cable tester
Use only cable ties to cinch groups of cable together

31. Installing Cable
Avoid laying cable across floor where it may sustain damage
Install cable at least three feet away from fluorescent lights or other sources of EMI
Always leave slack in cable runs
If running cable in plenum, area above ceiling tile or below subflooring, make sure cable sheath is plenum-rated
Pay attention to grounding requirements

32. Atmospheric Transmission Media
Infrared transmission
Infrared networks use infrared light signals to transmit data through space
Direct infrared transmission depends on transmitter and receiver remaining within line of sight
In indirect infrared transmission, signals can bounce off of walls, ceilings, and any other objects in their path

33. Atmospheric Transmission Media
RF transmission
Radio frequency (RF) transmission relies on signals broadcast over specific frequencies
Very susceptible to interference
Two most common RF technologies:
Narrowband
Concentrates RF energy at a single frequency
Spread spectrum
Distributed over several frequencies simultaneously

34. Choosing the Right Transmission Media
Areas of high EMI or RFI
Corners and small spaces
Distance
Security
Existing infrastructure
Growth