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Technology for High Performance WLANs Serving The Needs Of Higher Education.

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Presentation on theme: "Technology for High Performance WLANs Serving The Needs Of Higher Education."— Presentation transcript:

1 Technology for High Performance WLANs Serving The Needs Of Higher Education

2 2 Agenda Meru Networks – Our Mission Why 802.11 WLANs require QoS for Voice and Data Meru’s QoS Architecture Comparing QoS Solutions Converged Network Case Study High Performance b/g Network Co-Existence Location Based Services

3 3 Our Mission Design and manufacture 3 rd generation WLAN (Wi-Fi ) solutions for voice & data Comprehensive Security Easy Deployment & Management Transparent Mobility High Density QoS Zero Configuration Multi-layers 5x Number of Voice Calls 5x Number of Active Users 0 Loss - Handoff High Performance: With Meru Air Traffic Control Technology

4 4 Meru Wireless LAN Infrastructure Products Floor 2 Floor 1 Data Center L2 / L3 Backbone Virtual AP AP Meru Controller Meru AP  Coordinated Access Points ► Over-the-Air QoS ► Contention management  Controller ► Centralized appliance for management and security ► RF Interference Management ► Built-in application Flow-Detectors e.g. SIP, H.323, Cisco Skinny, Spectralink SVP ► Location Services

5 5 Wireless LAN Evolution Number of Clients and Coverage Applications Products / Technology Email, Web Stand-alone Access Points Stand AloneMulti-site Email, Web from different locations Centralized security and management High Density Application QoS Transparent mobility Full network integration Voice and Data Business applications Primary connectivity Video emerging Pervasive

6 6 Enterprise WLAN Product Evolution Generation 1 + Central Management Security 2000-01 1 st Generation 2002-3 2nd Generation 2003-4 3rd Generation Aggregated AP’s Central Switch/ Appliance Stand-alone APs Cisco 1200+SWAN Symbol Aruba, Trapeze, Airespace … Meru Generation 2 + RF Intelligence High Density QoS Zero Handoff Cisco 350 Proxim Linksys Basic Connectivity Services / Scale Coordinated AP’s Central Switch/ Appliance

7 7 University WLAN Requirements  High Density ► Lecture halls, classrooms, memorial unions, etc  High Mobility ► Students, faculty, visitors – constant movement  Data, Voice, and Video ► Data today ► Voice emerging – soft phones, dual mode cell phones ► Video – lecture content, video presentations, etc.  Integrated Security ► Student / faculty / guest security profiles ► Integration with network access control ► Location based security

8 8 WLAN Architectures Medium & large enterprise Scaleable, central management Centralized intelligence SOHO, Medium & large enterprise Target Markets Simple implementation for a few access points, Centralized Management Benefits Stand alone APs, Centralized or Distributed Management Architecture “Stand Alone” or Fat” AP “Thin” or “Fit” AP LAN Switch WLAN Switch / Controller Medium & large enterprise RF coordination, simple deployment, scaleable, central management Overlay WLAN network, distributed intelligence, centralized control “Intelligent” AP WLAN Switch / Controller

9 9 Key Requirements WLANs Security Easy Deployment & Management Transparent Mobility High Density QoS Priority for Voice Calls, Video Capacity for Active Users Zero Loss Handoff Air Traffic Control Technology With Standard WiFi Clients Take Control of the Converged WLAN

10 10 Issues for Voice & Data over Wi-Fi 1. Unpredictable behavior over-the-air  Random allocation of air time 2. Poor performance  Low user density  Low number of voice calls, call quality  Handoff 3. Security 4. Difficult to install 5. Difficult to manage

11 11 802.11 Challenges for Voice & Data The 4 fundamental problems that must be solved to achieve enterprise level performance for high density Voice and Data for Wi-Fi networks: 1. Single Cell Contention 2. Contention Across Cells 3. Jitter and Volatile Bandwidth Allocation 4. Slow Handoff

12 12 Problem 1: Contention within Single Cell 20 5 8 11 1 3 Baseband + Protocol Overhead Contention Loss Contention Loss Today’s AP Performance Number of Active Users Total Bandwidth at Peak (Mbps) Multiple clients contend for the same shared medium While transmitting sender cannot listen for collisions As number of calls goes up, collisions increase Collisions cause clients to backoff Backoff slows down network Requires more than scheduling S R I I I Air = Shared Medium

13 13 5.5/11 Mbps CS Receive Signal at AP 1 Mbps Distance Problem 2: Co-Channel Interference Across Multiple Cells Cell size Collision Domain Interference Domain Interference Range Is Much Larger Than Communications Range Mbps

14 14 Problem 3: Jitter & Bandwidth Allocation 5.465.485.55.525.545.56 Time (Sec) Channel Access with Today’s 802.11 AP 2 6 4 8 10 12 5.36 5.385.45.445.42 As number of calls goes up: Random channel access by clients causes latency & jitter AP gets less bandwidth (only 1/n th of channel) Erratic, unfair access over short term intervals (completely starved 2 clients) Channel Throughput 1 AP + 20 Clients

15 15 Problem 4: Slow Handoff Across Cells Beacon and Probes to join available ESSID 802.11 Association and Authentication process 802.1X Authentication or any other type of security authentications (includes Radius or other AAA servers) IP address assignment 100ms – 1 sec between handoff BSSID = ABSSID = B 01:00

16 16 Meru Networks - QoS Architecture Application Flow Detection Global RF Resource Knowledge Admission Control Control Mechanisms in 802.11 Standard Meru QoS Algorithms +  Global knowledge of interference and resource usage at AP’s including knowledge of clients  Time-based accounting, not bandwidth-based  Inter-cell Coordination  Deep packet inspection for understanding resource requirements of Application (e.g. SIP/Codec)  Resource management + +  Virtual carrier sense for uplink reservation/QoS  Contention-free periods and contention periods. Per-flow Scheduling  Uplink and Downlink accounting of packets / expected packets  Reservation-based QoS +

17 17 Meru Networks - Air Traffic Control Centralized Control - Global Policies - Global Coordination - Central RF Intelligence - App Flow Inspection MERU MAC - Local Governance - Dynamic QoS Flow Recognition - Distributed Rogue Detection & Mitigation Performed in Controller Performed in the Access Point Contention Management Algorithms Contention Suppression for QoS Flow Virtual MAC for Zero Handoff Voice Client Voice Client

18 18 Comparing Control of the Air How Meru Delivers Over-the-Air QoS Mgmt (Auth/Assoc/Probe) Beaconing Packet Fragmentation Scheduling/Queuing Lower MAC (CSMA/CA) PHY RF Integrated MAC/PHY  Access to the Lower MAC is critical to provide QoS  Decisions need to be made at microsecond level based on prior packet air conditions  Other AP’s queue packets asynchronously requiring decisions to be made several time intervals prior to transmission Reference- design AP Meru AP (with Meru MAC) 802.11 Phy/RF Asynchronous Interface Between SW And MAC/PHY Sychronous Interface Meru APOther APs

19 19  Predictable channel access  Predictable and low jitter  Support for higher number of clients 5.56 AP C6 C4 C8 C10 C12 5.36 5.385.45.44 5.465.485.55.525.54 5.42 Channel Access with Meru AP for QoS Flows Time (Sec) Application Flows with Over-the-Air QoS Air Traffic Control - The Result Meru AP

20 20 Meru Air Traffic Control Technology 5x More Users 20-25 Total Bandwidth at Peak (Mbps) 5 8 11 1 3 Contention Loss Contention Loss Today’s AP Performance Meru AP Performance Active Users Per AP TodayMeru 20-25 100+ 5X Number of Active Users Peak Aggregate Throughput

21 21 Generic Access Point + Standard Client Meru AP + Standard Client Meru Air Traffic Control Technology Over-The-Air QoS: 5X More Voice Calls Converged Network - voice and data on same channels Data and voice typically on Separate channels/network ~20-30 ~5-8 AP Wired QoS Standards-based Over-the-Air QoS AP Voice Quality MOS Score 4.0+ Over-the-air QoS

22 22 Meru Quality of Service - Results  Industry leading aggregate throughput at density  Predictable, uniformly fair throughput across all clients ► Other AP’s erratic, unfair access over short term intervals completely starved 2 clients  4X less loss rate (2% - 2.5%) ► Versus other AP’s 8% loss rate Throughput 1 AP + 20 Clients Throughput 1 Meru AP + 20 Clients

23 23 Meru Air Traffic Control Technology Results - Zero Loss Handoff Meru WLAN Virtual AP Architecture No Handoff For Client BSSID = M 00:00 100ms – 1 sec between handoff Today’s WLAN BSSID = ABSSID = B 01:00

24 24 Meru Quality of Service - Summary  Works with all standard 802.11 Wi-Fi clients  Fine grained upstream and downstream over-the-air QoS with easy provisioning ► Voice flow detectors (SIP, H.323, Vocera, Spectralink, Cisco) ► Real-time highest priority ► Application QoS Rules ► Real-time, user-configurable rules ► Client Fairness ► 8 priority queues ► Optimized throughput with Meru Air Traffic Control algorithms for predictable performance

25 25 How Meru Over-the-Air QoS Compares to Others Meru802.11e / WMM Today’s AP’s / “WLAN Switches” Global RF Knowledge and Inter-cell Coordination Yes-- Application Flow Detection and Classification Yes (Dynamic)-- Static ESSID-based or Filters Admission ControlYes-- Downlink (AP to Client) Reservation-based True over-the air QoS Low-scale Simple Priority of packets Uplink (Client to AP) Reservation-based True over-the air QoS Low-scale With Client-side HW/SW --

26 Customer Case Study

27 27 Jackson Memorial Hospital A Meru Customer Success Story Creating a Wireless LAN with better utilization across different applications is the right move for companies today. Enterprises require third generation Wireless LAN products with coordinated Access Points that permit greater scalability and centralized management. This will lead to a reduction in the overall costs of wireless infrastructure while improving performance. Rachna Ahlawat, Principal Analyst, Gartner Inc. ” “ University of Miami

28 28  Inability to manage contention needed to support high density environments  Cannot operate on a single channel to avoid interference with outdoor AP  Unable to deliver over-the- air QoS needed for mission- critical applications The Jackson Memorial Hospital Wi-Fi Challenge  A n indoor WLAN solution that could reliably co-exist with its existing outdoor AP’s  Future-proof system to support data today and voice in the future.  Support for high user density and broad range of devices Key RequirementsWhy Other Systems Fall Short

29 29  Meru system seamlessly connected to existing wired Cisco switches and works with any standard 802.11 client (phone, pda, laptops)  Dynamic over-the-air QoS supports reliable data services today and high-performance voice and video in the future Single Channel Deployment Leverage Existing Wired & Wireless Investments Meru Controller PBXVocera System Server Data Center Netscreen SSL VPN Outdoor AP Outdoor Laptops Vocera Badges Cisco Catalyst 6500 Virtual AP WiFi Phones PDAs Tablet PCs Laptops Floor 2 Floor 3 Floor 4 Floor 5 Floor 6 Floor 7 Cisco Catalyst Switch PAC Building Meru AP Cisco Catalyst Switch Network Admin Building

30 High Performance b/g Network Co-Existence

31 31 Why 802.11 b/g Co-Existence?  Backwards compatibility of b clients ► Large and growing installed base of b clients (Millions)  Utilize same AP infrastructure ► No new AP installations ► No RF re-planning  Higher channel efficiency for g networks ► Leverages the g network speed – 54 Mbps

32 32 The b/g Co-Existence Problems  Significant Co-Channel interference ► Only 3 spectrally independent channels ► Coverage required for high data rates  802.11b slows down g clients ► g client throughput reduced by 50%+

33 33 802.11b Slows g Clients  b client preamble and header impact control and data periods for g clients  Significant reduction in data rate – greater than 50% PreamblePLCPDataACK CTS PreamblePLCP Preamble PLCP Pre PLCPPLCP Data Pre PLCPPLCP ACK Pre PLCPPLCP Data Pre PLCPPLCP ACK 802.11b Only 802.11g Only 802.11g/b Carrier Sense Virtual Carrier Sense b Client g Client CCK OFDM > 2X micro sec. X micro sec.

34 34 Concurrent High Performance  Separate 802.11b and 802.11g networks into different BSSIDs ► Logically isolate b and g clients  Creates packet level interoperation ► Controlled channel access ► g only window ► b only window  Adaptively determine the window period ► Protocol content ► Flow-level info (upstream & downstream) ► Number of b clients ► Number of g clients

35 35 Deployment Architecture Meru Controller DHCP Server RADIUS Server Routed Core Virtual Wireless Subnet Meru AP to controller tunnels established over routed infrastructure  Separate BSSIDs for b and g clients  AP’s can advertise each b and g network (2 BSSIDs)  APs control channel access based on required b and g resources  APs utilize adaptive control algorithms to determine window period AP 802.11b ESSID #1 802.11g ESSID #2 b b g g g

36 36 Meru Eliminates Trade-Off Between Backward Compatibility and g Throughput UDP g (with b clients present) ~14.8 ~22.6 Vendor C Meru ~10.3 ~15.8 Meru ~3.4 ~10.1 Meru TCP 1g TCP 1g +1b g client perf. Source: Meru Lab Tests Vendor C

37 37 Summary  Breakthrough Air Traffic Control Technology Delivers Concurrent 802.11b and 802.11g with High Performance ► Simplify 802.11g deployment – no new APs ► Highest 802.11g throughput in mixed b/g networks ► Leverage deployed 802.11b clients ► Eliminate user performance compromise

38 Location Based Services

39 39 Planning / Site Survey – “Snap Shot”  Create Network Plan: ► Upload map (.jpg or.png file, no need for CAD drawings) ► Draw walls and other obstacles (optional) ► Place access points on the map ► Simulate the network coverage  Perform Site Survey ► Upload map (.jpg or.png file, no need for CAD drawings) ► Deploy the APs as per plan Survey the site - Measure the coverage ► Fix the coverage holes if any by adding APs or adjusting antennas

40 40 RF Visualization – “Real-Time” Visualize coverage based on signal strength, data rate, Determine which areas support given ESSID, or channels Visualize network performance and coverage holes Visualize Coverage

41 41 Location Tracking Applications  Real-time location of Rogues, clients ► Pinpoint rogue device (AP or client) to specific location (in a cubicle, in the hallway, outside the building) ► Allow connectivity only when client at specific location (e.g. inside building)  Real-time capacity management/troubleshooting ► Identify relevant portion of a network for capacity adjustment or troubleshooting based on caller’s location  Mobile asset tracking ► Locate critical equipment or assets in hospital, manufacturing, retail environments  E-911 support ► Meet regulatory requirements for calls that require emergency dispatch

42 42 Location Tracking Technology  Traditional approaches: ► Closest AP – find the AP that hears a signal the loudest ► Very coarse granularity (point in 60’x60’ or 3600 sq ft area) ► Triangulation – overlap coverage from 3 different APs ► Granularity of ~ 30’ ► Challenges: Reflection, attenuation, multi-path ► RF-Fingerprinting – predict signal strength at every grid point, and match against it ► Hours of RF signature training ( ‘can you hear me now?’ approach) ► Granularity of ~10’

43 43 Summary  Over-the Air QoS is required for Converged WLAN networks  Breakthrough Technology Delivers Concurrent 802.11b and 802.11g with High Performance  “Stay tuned” for Location based WLAN services

44 Thank You Nate Walker Director, Product Management

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