Wireless Networking for the
Smart Grid
Narasimha Chari
Chief Technology Officer
© 2011 Tropos Networks, Inc.
About Tropos
• Technology and
products company
• Outdoor mesh
routers and network
management
software
• 800+ customers in
50 countries
• 40+ patents
• Founded in 2000
• Headquarters in
Sunnyvale, CA
© 2011 Tropos Networks, Inc. | Page 2
Smart Grid requires broadband communications
Demand
Response
Renewable
Integration
Automated
Metering
SMART GRID
Field Data
Applications
Outage
Management
© 2011 Tropos Networks, Inc. | Page 3
PHEV
Management
Distribution
Automation
and Control
Power Quality and
Planning
Smart Grid bandwidth needs growing
Other applications
representing higher traffic
include:
• Substation Video
• PHEV Station
• Mobile GIS
• AVL
…and more in the future
© 2011 Tropos Networks, Inc. | Page 4
Tiered view of Smart Grid communications
© 2011 Tropos Networks, Inc. | Page 5
Tropos architecture components
© 2011 Tropos Networks, Inc. | Page 6
•
Wireless IP Mesh Routers
•
PTMP and PTP Radio Systems
•
Centralized Wireless Network
Management
GridCom: Distribution-Area Network
© 2011 Tropos Networks, Inc. | Page 7
Distribution Area Network requirements
• Availability
• Survivability
• Coverage
• Performance: Bandwidth & latency
• QoS
• Security
• Manageability
• Interoperability
© 2011 Tropos Networks, Inc. | Page 8
Reliability challenges at utility-scale
•
Very large service territories
Mix of urban, suburban and rural areas
Diverse application mix with different requirements
Stringent requirements
– Mission-critical apps need very high availability networks
(4 or 5 9's)
– Need for highly survivable networks to aid in service
restoration following outages
– Sub-cycle latencies (<20ms) for DA
Most utilities do not own licensed spectrum
•
Wireless is hard
•
•
•
•
© 2011 Tropos Networks, Inc. | Page 9
Techniques for high-reliability wireless
•
Hardware
–
–
–
–
•
Architecture
–
–
–
–
–
•
High-performance radios
Ruggedized outdoor-optimized hardware
Backup power options
MIMO techniques
Resilient mesh architecture (path and route diversity)
Opportunistic use of multiple bands (frequency band diversity)
Distributed channel coordination (channel diversity)
Combination of mesh and PTMP topologies
Fault detection and isolation
Cognitive radio techniques
– Adaptive modulation
– Transmit power control
– Adaptive noise immunity
© 2011 Tropos Networks, Inc. | Page 10
High Reliability Mesh Routers
•
•
Reliable
•
•
Self organizing fully redundant mesh
>99.99% system availability
•
-40ºC to 55ºC operating range
•
IP67 weather tight (NEMA 6+)
•
Available battery backup
•
IEEE 1613 compliant
Secure
•
•
•
Manageable
•
•
Multi-layer security – 802.1x, IPSec, AES
FIPS 140-2 certified
Monitoring, configuration, upgrades, fault
management, security
Multiple Applications
•
•
•
High bandwidth: up to 15Mbps
Low latency: 3-5ms per hop
Application QoS: 802.11e, 802.1p, VLANs
© 2011 Tropos Networks, Inc. | Page 11
Mesh architecture
Tropos mesh software leverages redundant paths, channels, frequencies,
and backhaul locations to create the most robust network possible
© 2011 Tropos Networks, Inc. | Page 12
Cognitive Radio Techniques for High Reliability
• Mesh architecture: inherently capable of routing around
interference through leveraging path diversity
• Multi-band radio technologies can efficiently and adaptively
exploit multiple frequency bands, with failover and loadbalancing between them (e.g., dual-mode 2.4/5 GHz)
• Dynamic frequency selection: ability to detect interference or
elevated noise levels and dynamically switch channels
• Transmit power control and adaptive modulation: techniques
for adapting radio transmission parameters in real-time to
maintain link reliability
© 2011 Tropos Networks, Inc. | Page 13
Private Network Architectures: Mesh and PTMP
PTMP Advantages
Mesh Advantages
Large coverage area
Resilient high-availability architecture
Compelling economics for sparse areas
Ideal solution for NLOS environments,
dense urban areas
Easy to deploy
High system capacity
PTMP Challenges
Mesh Challenges
LOS is challenging in urban areas
Requires pole-top mounting assets
Expensive site acquisition, construction
Economics for sparsely-populated areas
Hub-and-spoke architecture with single
point of failure
Management of many distributed assets
© 2011 Tropos Networks, Inc. | Page 14
PTMP and Mesh are Complementary
•
PTMP and Mesh are complementary technologies for the
DAN layer
– PTMP is very cost-effective rural deployments
– PTMP is suitable for mesh capacity injection in denser areas,
especially where there isn’t utility-owned fiber
– Mesh is well-suited for urban/suburban areas providing resilience
and higher capacity
•
Optimal combination of Mesh and PTMP leverages the
strengths of both
– Mesh extends coverage range of PTMP and improves reliability
– Architectural resilience through mesh failover capabilities
– Unification of mesh and PTMP components through Tropos
Control
– Combined deployment achieves
•
•
Economics optimized for mix of urban/suburban/rural areas
Meets requirements for multiple DAN applications
© 2011 Tropos Networks, Inc. | Page 15
What Optimal Technology Mix Looks Like
Data Center(s)
Tropos
Control
Tier 1 / Tier 2
Microwave
Tier 1: Fiber (SONET, GigE),
Microwave, MPLS Core
Tropos Gateway (GW)
Routers Installed at
Tier 1 Core Sites
Tropos Node (ND) Routers
Distribute Tier 2
Capacity Across
Urban/Suburban
Service Areas
Tier 1 Topology Implemented with
Path Diversity Where Possible
GW
GW
GW
Smart Grid Devices
Connect via Wired
or Wireless Ethernet
to Tropos Mesh Nodes
Rural Subscribers
Served via P2MP
P2MP Demarc to
Mesh Gateways
Decreasing Mesh Density
Tier 3 (NAN)
Tier 4 (HAN)
Dense
Urban
© 2011 Tropos Networks, Inc. | Page 16
Urban
Suburban
Transition to WiMAX/P2MP/LTE
Rural / Ultra Rural
Mesh Used in Rural
to Overcome P2MP
Propagation Obstacles
Thank you!
© 2011 Tropos Networks, Inc.