2. PROGRESSION LOW LATENCY NETWORKS
over
$4B
PRE-1970’S 70’-80’s 90’s-TODAY market
globally
MESSENGER SERVICES, DATA NETWORKS FIBER
PHYSICAL/HAND DELIVERY (ANALOG/DIGITAL)
ON COPPER
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3. NEXT STEP IN LOW LATENCY PROGRESSION:
MICROWAVE microwave uses more direct routes
(less distance)
propagation is 30% faster over air
MICROWAVE IS FASTER THAN FIBER AND IS QUICKLY BECOMING
DEFACTO STANDARD FOR ULTRA LOW LATENCY TRANSPORT
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4. WHAT IS USABLE LATENCY?
Functional, viable, practical. ???
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5. BUT MICROWAVE IS COMPLEX AND NEW TO
FINANCIAL SERVICES…
Number Co-Existence Network
Weather with Fiber
Hops (rain,
Management
propagation)
Path Design Installation
and Reliability
Regulatory
Issues
Latency
Sites and
Security
Acquisition
9. WHERE DOES LATENCY GO?
On a standard latency microwave link
SHORT FRAMES (64)
LONG FRAMES (1518)
0.15% Interface Speed
3.85% 0.39% 2.11% 0.08%
7.00% Switching & 5.13%
Serialization 21.13%
19.26% Transfer Buffers
38.52%
44.07%
Interleaving 16.91%
30.82%
Encoding/Decoding 10.57%
Mod/Demod
Analog Front End
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10. PAYLOAD INTERFACES AND SERIALIZATION DELAY
Ethernet Interfaces
L1 Interfaces (STM1/OC3)
Proprietary L1 Interfaces (Clock and Data)
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11. MODEM TECHNOLOGY
FEC Method Algorithm Latency SG Imp.
Linear and Iterative LPDC, Turbo Codes High High
Forward Error Correction Convolutional Codes Viterbi Medium Good
Block Codes Reed Solomon Low* Good*
128 QAM
256 QAM
16 QAM
32 QAM
64 QAM
No FEC --- Lowest None
Mod
QPSK
BW
30 MHz
40 MHz Modulations and Bandwidths
50 MHz
Diversity Protection
Improves link availability and hence low latency availability
Adaptive Modulation and Adaptive Coding Latency Increase
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12. LOW LATENCY… (OBVIOUSLY)
SO HOW DO WE REDUCE THE LINK LATENCY?
- High speed interfaces
~10-20 µs
- Use small frame sizes
- Early packet forwarding
- Reduce buffering wherever possible BOX
- Eliminate Interleaving
- Reduce or eliminate FEC
And equipment/box latency is easy to
understand/measure, but…
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13. THE REAL METRIC IS END-END LATENCY
(THIS IS WHERE IT GETS COMPLICATED…)
BOX
BOX
BOX
Exchange Exchange
BOX BOX
And best ways to lower end-end MW latency…
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14. REDUCE NUMBER AND COMPLEXITY OF THE HOPS
INTRODUCTION OF THE REPEATER CONCEPT
- Latency in Nx10 ns
- RF Repeater
- Limited RF Options
- Mask Limitations
- IF Repeater
- Frequency Agile
- Mask Limitations Regenerator Repeater Repeater Regenerator
Node Node Node Node
- Digital Repeater
- Frequency Agile
- Usually No Mask Limitations 30% reduction
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15. ADAPTIVE REPEATER TECHNOLOGY
Ultra Low
End-End
Latency
99% of time Regenerator Repeater Repeater Repeater Repeater Regenerator
Node Node Node Node Node Node
Low End-End
Latency
(still better
than fiber)
Regenerator Repeater Regenerator Repeater Repeater Regenerator
1% of time
Node Node Node Node Node Node
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16. RF AND MODEM PERFORMANCE
WHERE DOES IT HELP?
• Link Distance • Antenna Size
• Number of Hops • Number of Repeaters
• Link Availability
• Techniques include:
- Tx Power - FEC Coding
- Rx Sensitivity - Rx Threshold
- Diversity - Higher Quality Oscillators
Ultimately all revolves around having better System Gain !!!
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17. QUANTIFY RF / MODEM PERFORMANCE
Example: Chicago rain zone, 99.999 Availability, 6 Ft Antenna, 64QAM
Frequency Band Std System Gain +3dB
6 GHz 51.6 Miles 55.8 Miles
11 GHz 35.1 Miles 38.5 Miles
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18. AND MANAGING THE RELIABILITY /
LATENCY TRADEOFF
High Latency
End-End Good News: with
Latency new innovations,
best of both worlds
Low Latency can be achieved…
90% 99.999%
Path Uptime
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19. SO THAT’S LOW LATENCY…
BUT what good is low latency if your network is:
Thus a full featured microwave solution will be required
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20. BEST PRACTICE
FOR BUILDING LOW LATENCY
MICROWAVE NETWORKS:
FOCUS ON END-END LATENCY
USING A FULL-FEATURED
MICROWAVE PLATFORM
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23. VALIDATE THE ROUTE
Phase 1 - Planning and Design
• Regulatory
• Site Selection
• Frequency Coordination and Acquisition
• Transmission and Network Engineering
• Site & Path Survey
Is the route viable?
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24. SECURE THE SITES
Site Acquisition and Construction
• Site Acquisition and Leasing
• Engineering and Drafting
• Zoning
• Utilities and Construction
• System Engineering and Optimization
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25. BUILD AND LAUNCH THE NETWORK
Integration and Deployment
• Configuration and Network Engineering
• Factory Integration
• Equipment Staging
• Installation of Antennas, Lines & Ground
Equipment
• Radio Installation and Path Alignment
• Acceptance Testing & Commissioning
• Commercial Launch
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26. When the network is built…then what?
Focus on what you do best and let Microwave experts keep the
network running at optimal speed and efficiency
Peace of Mind!
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