Media & Cabling Distribution Flashcards
Coaxial Cable
Inner: Insulated conductor or center wire passes data
Outer: Braided metal shield used to help protect the data transmission (EMI resistance)
Coaxial Cable Types
RG-6: Used by local cable companies to connect individual homes
RG-59: Used to carry composite video between two nearby devices
Coaxial Cable Connectors
BNC (Bayonet Neill-Concelman - British Naval Connector):
Was used for 10BASE2 Ethernet Networks
F-Connector:
Typically used for cable TV & cable modem connections
Twisted Pair Cables
Most popular LAN media type
8 individually insulated strands of copper wire
Each pair twisted to reduce EMI
(Tighter twists = less EMI)
UTP & STP
UTP
Unshielded Twisted Pair
Media of choice in most LANs
Number of twists determines EMI amount blocked
(CAT6 has more twists per inch than CAT5)
STP
Shielded Twisted Pair
Wires are surrounded by a metallic shielding to minimize EMI
Shielding makes STP more costly and less flexible than UTP
Twisted Pair Connectors
RJ-45: 8-pin connector in Ethernet networks
Most Ethernet use only 4-pins
RJ-11: 6-pin connector (telephone systems)
Commonly only 2/4 pins are used
DB-9 or DB-25 (9 or 25-pin D-Subminiature)
Used for asynchronous serial communications & connecting to an external modem
Twisted Pair Cable Throughput
CAT3: 10Mbps - 100m CAT5: 100Mbps - 100m CAT5e: 1Gbps - 100m CAT6: 1Gbps - 100m CAT6a: 10Gbps - 100m CAT7: 10Gbps - 100m
Straight-Through Patch Cables
Both ends of the cable have matching pin outs
T-568B is the preferred standard for wiring a building
DTE to DCE
Data Terminating Equipment to Data Communications Equipment
Examples: Computer to switch
Router to modem
Crossover Cables
Send & receive pins of the cable are swapped in the end pin outs.
Used to connect two workstations
Or a switch to a switch
(Not required if switch supports MDIX)
T568B vs. T568A
T568B:
OW, O, GW, B, BW, G, BrW, Br
T568A:
GW, G, OW, B, BW, O, BrW, Br
Fiber Optic Cables
Use light from LED or laser to transmit info through glass fiber.
Immune to EMI, uses light instead of electricity
Great range, greater data-carrying capacity (Tbps)
Types: MMF & SMF
MMF
Multimode Fiber
Shorter distances than single-mode
Larger core sizes allows for multiple modes of travel for the light signal (62.5 microns)
Uses: Routers to switches
Switches to switches
Servers to switches
SMF
Single-Mode Fiber
Longer distances than multimode
Smaller core allows for only a single mode of travel for the light signal (10 microns)
Uses: Routers to switches
Switches to switches
Fiber Optic Connectors
SC (Subscriber Connector) - “Stick & Click”
ST (Straight Tip Connector) - “Stick & Twist”
LC (Lucent Connector) - Looks like two SCs
MTRJ (Mechanical Transfer Registered Jack)
Refer to diagrams on Dion study guide
Copper vs. Fiber Optic Cables
Fiber Optic: (40Km+, 69Tbps+) Higher bandwidth longer distances Immune to EMI Better security
Copper: (<100m, 10Gbps)
Less expensive
Easy to install
Inexpensive tools
Media Converters
Convert media from one format to another
Layer 1 Device (physical conversion of signal only)
Ethernet to Fiber Optic
Fiber Optic to Ethernet
Coaxial to Fiber
Fiber to Coaxial
Cable Distribution System Components
Entrance Facilities Main Distribution Frame (MDF) Cross-connect Facilities Intermediate Distribution Frame (IDF) Backbone Wiring Telecommunications Closet Horizontal Wiring Patch Panels Work Area
Punch Down Blocks
66 Block:
Used for phones & older LAN wiring
Causes crosstalk due to proximity of cables
Do not use for CAT5 and above
110 Block:
Used for higher-speed network wiring
Required for CAT5 and above
Krone Block:
A proprietary European alternative to a 110 block
BIX Block:
Another proprietary punch down block (various sizes)
Requires a BIX specific punch down tool
Patch Panels (Copper)
Device with jacks to connect wiring from the jack to a network switch in a flexible manner
Back has punch downs like a 110 block to connect wiring to wall jacks in building
Front has RJ-45 jacks
Patch Panels (Fiber)
Connect fiber jacks throughout building to a single patch panel in network closet
Front uses patch cables to connect to different wall jacks & switch ports
Fiber Optic Connector Types
SC (Stick & Click)
ST (Stick & Twist)
LC (Love Connector - Like two SCs attached)
MTRJ (Looks like an RJ-45 kind of; one plastic piece with two connectors)
Specialized Fiber Optic Connectors
APC (Always Green) - Usually for SC
UPC (Always Blue) - Usually for MTRJ
WDM
Wavelength Division Multiplexing:
Combines multiple signals into one signal & sends over a single fiber optic strand using different wavelengths of the laser light source
Coarse WDM (CWDM)
Up to 18 channels
20nm
Up to 10Gpbs (Ethernet)
Up to 16Gbps (Fiber)
Dense WDM (DWDM)
Up to 80 channels
0.8nm
Up to 8 Tbps
(100Gbps/channel)
GBIC
Standard, hot-pluggable gigabit ethernet transceiver (copper/fiber)
SFP
Small Form-Factor Pluggable (Mini GBIC)
Compact, hot-pluggable optical module transceiver
Up to 4.25Gbps
SFP+
Enhanced SFP
Up to 16Gbps
QSFP
Quad Small Form-Factor Pluggable
Compact, hot-pluggable optical module transceiver
Up to 40Gbps
QSFP+ = 41.2Gbps QSFP28 = 100Gbps QSFP56 = 200Gbps
