Title: Thinnet 10Base2
1Thinnet (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
2Thinnet (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
3Twisted-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 cables transmission
Figure 21 Twisted-pair cable
4Shielded 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
5Unshielded 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
6Unshielded 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
7Unshielded 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
810BaseT
- Popular Ethernet networking standard that
replaced 10Base2 and 10Base5 technologies - T for twisted pair
Figure 4-25 A 10BaseT Ethernet network
910BaseT
- Enterprise-wide network
- Spans entire organization
- Often services needs of many diverse users
Figure 4-26 Interconnected 10BaseT segments
10100BaseT
- 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)
11100BaseVG
- Cousin of Ethernet 100 Mbps technologies
- VG stands for voice grade
- Also called 100VG-AnyLAN
- Originally developed by Hewlett-Packard and ATT
- Now governed by IEEE standard 802.12
- Requires more sophisticated NICs and can reduce
network performance
12Comparing STP and UTP
- Throughput
- 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
13Fiber-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
14Fiber-Optic Cable
- 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
15Fiber-Optic Cable
- Throughput
- 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
16Fiber-Optic Cable
- Two popular connectors used with fiber-optic
cable - ST connectors
- SC connectors
Figure 4-30 ST and SC fiber connectors
17Fiber-Optic Cable
- Noise immunity
- 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
1810BaseF and 100BaseFX
- 10BaseF
- 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
19Physical Layer Networking Standards
Table 4-3 Physical layer networking standards
20Cable Design and Management
- 1991 TIA/EIA released its joint 568 Commercial
Building Wiring Standard - TIA Telecommunication Industry Assoc.
- www.tiaonline.org
- EIA Electronic Industries Assoc.
- www.eia.org
- T568A
- T568B
21Cable 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
22Cable 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
23Cable 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)
24Cable Design and Management
- Horizontal wiring
- Max distance is 100m
Figure 4-33 Horizontal wiring
25Cable 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
26Cable Design and Management
Figure 4-35 A structured cabling hierarchy
27Installing Cable
Figure 4-36 A typical UTP cabling installation
28Installing Cable
T568A Standard
Table 4-5 Pin numbers and color codes for an
RJ-45 connector
29Installing 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
30Installing 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
31Installing 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
32Atmospheric 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
33Atmospheric 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
34Choosing the Right Transmission Media
- Areas of high EMI or RFI
- Corners and small spaces
- Distance
- Security
- Existing infrastructure
- Growth