Transcript No Slide Title

NETWORK
DESIGN
• Customer requirements
• Network topologies
• Cable choice
• Hardware
• TSB 75
• TSB72
Customer Requirements
• Nature of traffic
– Email
– Video
• Security
– Of data
– Of closets
• EMI
– Fluorescent lighting
– Motors
• Site
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–
Campus
Occupied
Listed
Run lenghts
• Future proofing
– Bit rates
– EMI
– Security
Customer Requirements
• Cost
– Installation
– Maintenance
– Long V's Short term
• Environment
– Open plan
– Office
– Rearrangement
frequency
Network Topologies
• CHOICE OF TOPOLOGY DEPENDS ON
– LAYOUT OF BUILDING
– AMOUNT OF EQUIPMENT TO BE CONNECTED
– TYPE OF EQUIPMENT TO BE CONNECTED
– PERFORMANCE REQUIREMENTS
– COST
Network Topologies
• POINT TO POINT
TOPOLOGY
– DIRECT CONNECTION
BETWEEN TWO PIECES
OF EQUIPMENT
Network Topologies
• BUS TOPOLOGY
– NODES CONNECTED TO A
SINGLE WIRE
– PROBLEMS DIFFICULT TO
ISOLATE
– MAIN CABLE FAILS ENTIRE
NETWORK FAILS
– EASY TO MODIFY
Network Topologies
• STAR TOPOLOGY
– SEVERAL DEVICES OR NODES
CONNECTED TO A CENTRAL
HUB
– RELIABLE
– ONE MALFUNCTIONING NODE DOES
NOT UPSET THE REST OF THE
NETWORK
– FLEXIBILITY
– NODES CAN BE ADDED OR REMOVED
WITHOUT DISRUPTING SYSTEM
– MORE CABLE REQUIRED THAN
A RING OR BUS TOPOLOGY
Network Topologies
• RING TOPOLOGY
– NODES CONNECTED IN CLOSED
LOOP
– DATA PASSED FROM NODE TO
NODE TO TARGET DESTINATION
– NODE FAILS - NETWORK MAY
FAIL
– ADDITION OF NODE ONLY WHEN
NETWORK INOPERATIVE
Network Topologies
• PHYSICAL STAR
– RING
CONFIGURATION
– STAR TOPOLOGY
Network Topologies
• COLLAPSED
BACKBONE
– SIMILAR TO STAR
Network Topologies
• SHARED NETWORK
Network Topologies
• SWITCHED NETWORK
Network Topologies
Cable Choice
• UTP
• FTP, STP, ScTP
• Wireless
• Fibre
UTP
• Horizontal
• EMC (Electromagnetic Compatibility)
• Not resistant to EMI
• Crosstalk
• Not secure
• Cheap
• Carries up to Gigabit speeds
• Distances
Screened
• FTP, STP, ScTP
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as with UTP but
Better resistance to EMI
Better resistance to Crosstalk
Needs grounding
More expensive (labour)
Wireless
• Shared 54Mbps channel
• Ease of installation
• No cable
• Susceptible to EMI
Fibre
• Multimode
• Singlemode
• Secure
• Cost
• Distances
• Bandwidth
Hybrids
• Copper
• Fiber
• Multimode / Singlemode
• Future proofing
• Cost
Switch
• Central component of star topology
• Regenerates and repeats data
• Extended distances
• Dedicated bandwidth
– Switching
• Same media (e.g.. Ethernet)
Router
• Connects two LANs together
• Routes data from source to destination
• Reduces network traffic
• Improves performance
• Relatively high cost
• Extended distances
• Mixed media (e.g. Ethernet & token ring)
• Mixed protocols (.eg. TCP/IP & Novell IPX)
Consolidation point
• Zone distribution
• Open office cabling
– Consolidation point
• Must be at least 15m from telecomms closet
• Should be limited to serving a maximum of 12 work areas.
• Located is fully accessible, permanent locations
• Was known as TSB72 in EIA standards
Zone Distribution
TIA/EIA-568-B.1 6.4.2
Consolidation point (TSB 75)
•
Advantages
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Transition point allowed along 90m
Office divided into zones
Only short run at transition point moved when office moves
Less disruption
Less lost productivity
Work area leads can be lengthened if run is less than 90m
Is not meter for meter (see table)
Leads have higher attenuation
Patch leads
• The connection from the CP to the TO uses solid core copper.
• The option is available to use a stranded cable but the total
•
•
maximum length of your link is reduced
Stranded cable has 20% higher attenuation so the total length
of your link must be reduced
Option to use a 26AWG cable
– 50% higher attenuation
– must adjust figure in table accordingly
11801 and TIA/EIA-568-B.1
• Centralised Optical Architecture
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Previously called TSB 72
Usually for fibre systems
Can use copper
300 meter length limit (including patch cord in TIA/EIA version
only)
– ISO have 3 link lengths of 300, 500 & 2000 m
• Also a number of application link lengths
– Electronics on one floor
– Higher densities on hubs
– Less space used