The Fusion of IP and Wireless

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The Fusion of IP and Wireless
Jacob Jorgensen president, CTO and
founder jacob_at_malibunetworks.com
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The problemWireless broadband should be
incredibly important, but it isnt
yet
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Wireless should be an important broadband option

• Broadband is exploding
• Millions of additional subscribers want broadband
  services, but cant be reached with DSL and cable
  modems
• Wireless should be an answer
• it could reach many of these subscribers
• it needs only one truck roll
• it needs no cable conditioning
• it can operate faster than cable modems and DSL
• wireless operators arent dependent on the LEC
• in some countries, wireless is the only
  economical choice

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But today, wireless is only a very small part of
the broadband market
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Why?

• Wireless is too expensive
• Wireless is too slow
• Wireless cant get through the trees
• Wireless is too hard to install
• Wireless cant guarantee bandwidth levels
• Wireless cant support QoS for voice, video, and
  data

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What is the ideal solution?

• A complete IP-aware wireless broadband system
• Consistent with the emerging 802.16.3 / .4
  standard
• Optimized for SME and residential
• World-class RF technologies, including burst-mode
  OFDM, which deliver
• high RF throughput
• non-line-of-sight operation
• high subscriber penetration
• A unique broadband access QoS architecture, which
  delivers
• bandwidth guarantees
• guaranteed, bandwidth-efficient support for voice
  and video
• high protocol throughput

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What do operators need in a wireless broadband
system?
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meeting the operators needs
Every part of the Internet impacts every other
part subscribers only care about their experience
PROTOCOLPERFORMANCE
PRIMARILY INTERNETWORKING
Differentiated services that meet the needs of an
increasingly sophisticated user base
Differentiated services that give users what they
expect and increase operator profits
Easy to install and manage another key element
of system cost
Equipment costs that meet the subscriber
expectation for residential broadband
PRIMARILY RF
A system that keeps subscriber data moving
Maximize bandwidth, and at a minimum, more than
DSL or cable
Penetration to a high of potential subscribers
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OFDM very resilient, non-line-of-sight

• Single carrier uses one large carrier
• Interference and multipath can block the entire
  signal
• Errors often require retransmission

• OFDM uses many small carriers
• Interference and multipath affect only a small
  portion of the signal
• Most errors can be completely recovered with
  forward error correction

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Dynamic modulation and FEC optimizing throughput
and resiliency
Subscriber further from base station with more
obstacles lower-order modulation, maximum
forward error correction
Subscriber close to base station with few
obstacles higher-order modulation, minimum
forward error correction
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Dynamic TDD optimal, dynamic balance of upstream
and downstream bandwidth
Frame 1
Downstream
Upstream
Frame 2
Downstream
Upstream
Frame 3
Downstream
Upstream
Frame 4
Downstream
Upstream
Frame 5
Downstream
Upstream
Downstream
Bandwidth adjusts dynamically, frame by frame,
based on user demand
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Quality of Service
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Problems of present broadband wireless systems

• Limitation in number of subscribers
• Limited services and features
• Inability to support real-time multimedia
• Inability to manage subscriber usage
• Inability to enforce access policies
• Inability to provide broadband and narrowband
  services simultaneously
• Low revenue profit/RF Hz/system/month

All adversely affecting the service providers
business model
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What is a reasonable definition of QoS in a
broadband wireless system?

• No added jitter or latency for time sensitive
  data
• No added errors for error sensitive data
• Minimal added traffic shaping
• Guaranteed Services
• Differentiated Services
• Best Efforts Services
• Ability to isolate effects of traffic types
  from each other
• Ultimate test is mixture of real-time
  multimedia traffic and best efforts FTP and
  UDP traffic

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System-level approaches for wireless QoS

• MAC layer must have a design specifically
  optimized for TCP/IP and UDP data transport
• TCP and UDP traffic must be segregated
• Link layer must be IP aware
• Media access methodology must be deterministic
  so that timing requirements of flows can be met
• System resources must be allocated on basis of
  traffic types and priorities
• Scheduling of IP data transport must be done
  in a manner consistent with timing requirements
  of data
• Hierarchical link sharing must be utilized

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Why an IP-aware protocol architecture is
essential for wireless broadband IP access
Wireline Wireless
Bit error rate Low High
Bandwidth scope Infinite Fixed
Typical topology Point-to-point Point-to-multipoint
Jitter, due to point-to-multipoint topology Low High
Ideal Solution
Adaptive ARQ, Adaptive FEC, Adaptive modulation
Predictive bandwidth reservation
Centralized protocol analysis and scheduler
Fast packet multiplexing, intelligent packet scheduling
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Intelligent packet scheduling guarantees QoS for
voice and video
Service provider network
FTP
HTTP
TELNET
MAC
SMTP
1
2
3
4
5
1
VoIP
Wireless broadband system
Non-optimally scheduled flows jitter and latency
are introduced
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Intelligent packet scheduling guarantees QoS for
voice and video
IP QoS-aware packet scheduler
Service provider network
MAC
1
3
4
1
2
5
Wireless broadband system
Non-optimally scheduled flows jitter and latency
are introduced
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IP flow analysis centralized scheduling
optimize bandwidth efficiency enforce QoS
Subscriber Applications
CPE
CPE IP Flow Manager
CPE
Subscriber Applications
CPE IP Flow Identifier
CPE IP Flow Manager
CPE IP Flow SAR Framer
CPE IP Flow Identifier
CPE IP Flow SAR Framer
MAC Frames over RF Media
CPE
CPE IP Flow SAR Framer
CPE IP Flow Manager
CPE IP Flow Identifier
Subscriber Applications
From SP network backbone
CPE IP Flow SAR Framer
Example IP Flow Priorities
CPE IP Flow Identifier
CPE IP Flow SAR Framer
Latency-sensitive UDP
High-priority
CPE IP Flow Manager
Intermediate-priority
CPE IP Flow Identifier
Initial HTTP screens
Subscriber Applications
Latency-neutral
CPE IP Flow Manager
IP Flow Scheduler
SAR and Framer
IP Flow Analyzer
FTP, SMTP, etc.
CPE
Low-priority
Base station
Subscriber Applications
CPE
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IP flow analysis centralized scheduling
optimize bandwidth efficiency enforce QoS
Subscriber Applications
CPE
Uplink IP Flow Reservation Scheduler
CPE IP Flow Identifier
CPE
Subscriber Applications
CPE IP Flow Manager
CPE IP Flow Identifier
CPE IP MAC SAR Framer
CPE IP Flow Manager
CPE IP MAC SAR Framer
MAC Frames over RF Media
CPE
CPE IP MAC SAR Framer
CPE IP Flow Identifier
Subscriber Applications
CPE IP Flow Manager
To SP NETWORK BACKBONE
CPE IP MAC SAR Framer
Example IP Flow Priorities
CPE IP Flow Manager
CPE MAC SAR Framer
Latency-sensitive UDP
High-priority
CPE IP Flow Identifier
Intermediate-priority
CPE IP Flow Manager
Subscriber Applications
Initial HTTP screens
Latency-neutral
CPE IP Flow Identifier
IP Flow Scheduler
SAR and Framer
IP Flow Analyzer
FTP, SMTP, etc.
CPE
Low-priority
Base station
Subscriber Applications
CPE
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Predictive bandwidth reservation for voice and
video
MAC Frame Scheduler
Downlink SubFrames
Uplink SubFrames
(Current frame N)
Increasing Slot Number
Increasing Slot Number
N
N1
N2
N3
Frame Sequence Number
N4
N5
N6
Nx
Voice, video advance reservations
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Wireless throughput and QoS overall impact of
an IP-aware architecture

yi
y1
y2
y3
Increasing QoS
y4
y5
y6
y7
y8
Internet backbone
Service provider network
Wireless system
Subscriber site
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Lets summarize
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Lets summarize what do operators need?

• A signal that can reach a high percentage of
  subscribers
• Very high data rates (up to 240 Mbps per base
  station)
• A scalable, reliable system thats easy to
  install and manage
• A system thats cost-effective enough to serve
  the consumer broadband market
• The ability to sell -- and genuinely deliver --
  SLAs
• Great QoS support for voice, video, and data
• Maximum operator revenues and profits, due to
• service level agreements
• very high bandwidth efficiency
• strongly differentiated capabilities