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The Fusion of IP and Wireless. Jacob Jorgensen president, CTO and founder jacob@malibunetworks.com. The problem: Wireless broadband should be incredibly important, but it isn’t…. … yet. Wireless should be an important broadband option. Broadband is exploding
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The Fusion of IP and Wireless Jacob Jorgensen president, CTO and founder jacob@malibunetworks.com
The problem:Wireless broadband should be incredibly important, but it isn’t… … yet
Wireless should be an important broadband option • Broadband is exploding • Millions of additional subscribers want broadband services, but can’t 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 aren’t dependent on the LEC • in some countries, wireless is the only economical choice
But today, wireless is only a very small part of the broadband market
Why? • Wireless is too expensive • Wireless is too slow • Wireless can’t get through the trees • Wireless is too hard to install • Wireless can’t guarantee bandwidth levels • Wireless can’t support QoS for voice, video, and data
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
VOICE AND VIDEO SLAs INSTALLABILITY & MANAGEABILITY PER-SUBSCRIBER COST RELIABILITY BANDWIDTH COVERAGE meeting the operator’s 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
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
residential residential tower 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
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
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 provider’s business model
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
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
Why an IP-aware protocol architecture is essential for wireless broadband IP access
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
FTP HTTP TELNET SMTP VoIP Intelligent packet scheduling guarantees QoS for voice and video IP QoS-aware packet scheduler Service provider network MAC 1 2 3 4 5 1… Wireless broadband system Non-optimally scheduled flows: jitter and latency are introduced
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 Subscriber Applications CPE IP Flow SAR & Framer CPE IP Flow Identifier CPE IP Flow Manager 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 Analyzer IP Flow Scheduler SAR and Framer FTP, SMTP, etc. CPE Low-priority Base station Subscriber Applications CPE
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 Subscriber Applications CPE IP MAC SAR & Framer CPE IP Flow Identifier 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 Analyzer IP Flow Scheduler SAR and Framer FTP, SMTP, etc. CPE Low-priority Base station Subscriber Applications CPE
Predictive bandwidth reservation for voice and video MAC Frame Scheduler Downlink SubFrames (Current frame = N) Uplink SubFrames Increasing Slot Number Increasing Slot Number N N+1 N+2 N+3 Frame Sequence Number N+4 N+5 N+6 N+x Voice, video advance reservations
With IP-aware architecture Without IP-aware architecture 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
Let’s 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 that’s easy to install and manage • A system that’s 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