bestpracticesforbuildingultra lowlatencymicrowavenetworks pdf 121220160705 phpapp01
TRANSCRIPT
1
BEST PRACTICES FOR BUILDING ULL NETWORKS
PROGRESSION LOW LATENCY NETWORKS
FIBER DATA NETWORKS (ANALOG/DIGITAL)
ON COPPER
MESSENGER SERVICES, PHYSICAL/HAND DELIVERY
AVIAT NETWORKS
PRE-1970’S 70’-80’s 90’s-TODAY over $4B
market globally
NEXT STEP IN LOW LATENCY PROGRESSION: MICROWAVE
AVIAT NETWORKS
MICROWAVE IS FASTER THAN FIBER AND IS QUICKLY BECOMING DEFACTO STANDARD FOR ULTRA LOW LATENCY TRANSPORT
microwave uses more direct routes (less distance)
propagation is 30% faster over air
Functional, viable, practical. ???
WHAT IS USABLE LATENCY?
AVIAT NETWORKS
Weather (rain,
propagation)
Reliability Installation
Sites and Acquisition
Number Hops
Path Design and
Regulatory Issues
Network Management
Co-Existence with Fiber
Security
Latency
BUT MICROWAVE IS COMPLEX AND NEW TO FINANCIAL SERVICES…
3 ULL MICROWAVE QUESTIONS
AVIAT NETWORKS
Full size image
AVIAT NETWORKS
RELEVANT TECHNICAL CONSIDERATIONS
AVIAT NETWORKS
Equipment Latency Payload Interface Serialization Delay Modem Technology
End-to-End Latency Repeaters RF and Modem Performance
Operational Considerations
WHERE DOES LATENCY GO? On a standard latency microwave link
0.39%
7.00%
19.26%
30.82%
38.52%
3.85%
0.15%
SHORT FRAMES (64)
Interface Speed
Switching &Serialization
Transfer Buffers
Interleaving
Encoding/Decoding
Mod/Demod
Analog Front End
5.13%
44.07%
10.57%
16.91%
21.13%
2.11% 0.08%
LONG FRAMES (1518)
AVIAT NETWORKS
PAYLOAD INTERFACES AND SERIALIZATION DELAY
AVIAT NETWORKS
Ethernet Interfaces L1 Interfaces (STM1/OC3) Proprietary L1 Interfaces (Clock and Data)
MODEM TECHNOLOGY
Forward Error Correction Modulations and Bandwidths Diversity Protection
Improves link availability and hence low latency availability Adaptive Modulation and Adaptive Coding Latency Increase
AVIAT NETWORKS
FEC Method
Linear and Iterative
Convolutional Codes
Algorithm
LPDC, Turbo Codes
Viterbi
Latency
High
Medium
Block Codes
No FEC
Reed Solomon
- - -
Low*
Lowest
SG Imp.
High
Good*
None
Good
BW 30 MHz
40 MHz
Mod
16 Q
AM
32 Q
AM
50 MHz
128
QA
M
64 Q
AM
256
QA
M
QPS
K
LOW LATENCY… (OBVIOUSLY) SO HOW DO WE REDUCE THE LINK LATENCY?
AVIAT NETWORKS
- High speed interfaces - Use small frame sizes - Early packet forwarding - Reduce buffering wherever possible - Eliminate Interleaving - Reduce or eliminate FEC
And equipment/box latency is easy to understand/measure, but…
~10-20 µs
BOX
THE REAL METRIC IS END-END LATENCY (THIS IS WHERE IT GETS COMPLICATED…)
AVIAT NETWORKS
Exchange
And best ways to lower end-end MW latency…
BOX Exchange
BOX BOX
BOX BOX
REDUCE NUMBER AND COMPLEXITY OF THE HOPS INTRODUCTION OF THE REPEATER CONCEPT
AVIAT NETWORKS
- Latency in Nx10 ns - RF Repeater
- Limited RF Options - Mask Limitations
- IF Repeater - Frequency Agile - Mask Limitations
- Digital Repeater - Frequency Agile - Usually No Mask Limitations
Regenerator Node
Regenerator Node
Repeater Node
Repeater Node
30% reduction
Regenerator Node
Repeater Node
Repeater Node
Regenerator Node
Repeater Node
Repeater Node
Regenerator Node
Repeater Node
Repeater Node
Regenerator Node
Repeater Node
Regenerator Node
ADAPTIVE REPEATER TECHNOLOGY
AVIAT NETWORKS
Ultra Low End-End Latency
Low End-End Latency (still better than fiber)
99% of time
1% of time
RF AND MODEM PERFORMANCE WHERE DOES IT HELP?
AVIAT NETWORKS
• Link Distance • Number of Hops • Link Availability
• Techniques include: - Tx Power - Rx Sensitivity - Diversity
• Antenna Size • Number of Repeaters
- FEC Coding - Rx Threshold - Higher Quality Oscillators
Ultimately all revolves around having better System Gain !!!
QUANTIFY RF / MODEM PERFORMANCE
AVIAT NETWORKS
Example: Chicago rain zone, 99.999 Availability, 6 Ft Antenna, 64QAM
Frequency Band
6 GHz
11 GHz
Std System Gain
51.6 Miles
35.1 Miles
+3dB
55.8 Miles
38.5 Miles
AND MANAGING THE RELIABILITY / LATENCY TRADEOFF
AVIAT NETWORKS
End-End Latency
Path Uptime
Low Latency
High Latency
99.999% 90%
Good News: with new innovations,
best of both worlds can be achieved…
AVIAT NETWORKS
SO THAT’S LOW LATENCY…
Thus a full featured microwave solution will be required
BUT what good is low latency if your network is:
BEST PRACTICE FOR BUILDING LOW LATENCY MICROWAVE NETWORKS: FOCUS ON END-END LATENCY USING A FULL-FEATURED
AVIAT NETWORKS
MICROWAVE PLATFORM
AVIAT NETWORKS
ULL MICROWAVE LIFECYCLE
And path planning is more than just GPS Coordinates and Google Maps! AVIAT NETWORKS
VALIDATE THE ROUTE
AVIAT NETWORKS
Phase 1 - Planning and Design • Regulatory • Site Selection • Frequency Coordination and Acquisition • Transmission and Network Engineering • Site & Path Survey Is the route viable?
SECURE THE SITES
AVIAT NETWORKS
Site Acquisition and Construction • Site Acquisition and Leasing • Engineering and Drafting • Zoning • Utilities and Construction • System Engineering and Optimization
BUILD AND LAUNCH THE NETWORK
AVIAT NETWORKS
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
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! AVIAT NETWORKS
AVIAT NETWORKS
Functional, viable, practical. ???
MAXIMIZE PROFITABILITY OF THE NETWORK
AVIAT NETWORKS
THANK YOU
AVIATNETWORKS.COM