Wireless Lan (PDF) by liuhongmei



    Wireless Lan

  Haben Sie Fragen oder wünschen eine
Beratung, eine kostenlose Teststellung oder
          weitere Informationen?

           Tel.: 02203 – 96960
          Mobil: 0174 - 9222144

                 XNC GmbH
             Auf der Kaiserbitz 3
                D-51147 Köln
         Amtsgericht Köln HRB 25563
       Geschäftsführer Frank Bergknecht
Installationen mit Meru’s
WLAN System
Meru Überblick
x   Meru zielt auf zwei der derzeit am stärksten
    IT Wachstumsmärkte —VoIP and Wireless

x   Innovative Technologie
     q   Eliminiert die derzeit komplexe RF Planung
     q   High performance, High density (Leistung und Dichte)
     q   Liefert High-Quality wireless VoIP

x   Industrielle Auszeichungen
Die Industrie sieht derzeit Meru als
 WLAN Architektur Evolution
                                            Aruba, Trapeze,
                 “Stand Alone” or           Extreme, Airespace              “Intelligent &
                     “Fat” AP                    “Thin” AP                Coordinated” Edge

                                               WLAN Switch                      WLAN Switch
                     LAN Switch
                                                                                 / Controller

Architecture       Stand Alone APs,         Centralized Intelligence     Overlay WLAN Network,
               Centralized or Distributed                                Distributed Intelligence,
                     Management                                            Centralized Control

Benefits       Simple Implementation for      Scaleable, Central        RF Coordination, Over-the-
                  a Few Access Points,           Management            Air QoS, Simple Deployment,
                Centralized Management                                    Scaleable, Management

Target          SOHO, Medium & Large           Medium & Large             Large Scale Enterprise
Markets              Enterprise                  Enterprise
2005 – Unstrung Insider:
Enterprise VOIP Mobility Leadership
                                As of August, 2005
5 Top Equipment Makers Pick Meru for
Wireless VoIP Solution
  VoIP Server           Wireless LAN                   Handsets

                +                              +
                                                   Wi-Fi     Dual-mode

                                                   Handset   Handset

                    Wireless / VoIP Security
Meru’s Unique Solution Advantages
Compared to Extreme’s WLAN
 Better WLAN Performance
   •   Predictable, fair service to all clients
   •   Higher performance in dense user environments
   •   Higher performance in mixed-mode 802.11b & 802.11g clients

 Easy Deployment
   •   Co-channel Interference Management
   •   Reduced RF planning

 Better Mobility/Roaming
   •   Zero Handoff vs. Slow Handoff

 Better QoS / VoWLAN Support
   •   Over-the-air upstream and downstream QoS
   •   Automatic voice flow detection (SIP, H323, SVP, SCCP)
   •   Advanced Call-Admission Control, call load-balancing
       and dynamic error correction capabilities
Meru Differentiation:
Air Traffic Control (ATC)

                                Functionality             Benefits
                            Centralized Control
                            -   Global Policies
                            -   Global Coordination       Management
                            -   Central RF Intelligence
                            -   App Flow Inspection

                            AP Intelligence               Co-Channel
                            - QoS Flow Recognition        Management
                            - Application Detection
                            - Local RF Coordination
                            - Admission Control
                                                           Jitter and
                            ATC MAC                       Bandwidth
                            - Local Governance            Management
                            - Scheduling
                            - Virtual MAC for Clients
                            - 802.11 Control
                                                          Zero Handoff

                       Performed in Controller

                       Performed in the Access Point
          Air Traffic Control Technology
          More Bandwidth For More Users

                                       Peak Aggregate Throughput                    Active Users Per AP

Total Bandwidth at Peak


                                   8                                  Meru AP


                                       Today’s AP
                                   1   Performance
                                          3                   20-25
                                                                                    Others      Meru
                                          Number of Active Users
Air Traffic Control Technology :
More Voice Calls

      over-the-air                    Over-the-Air
         QoS                Wired        QoS
                     AP                                       Wired
                            QoS                          AP   QoS



                                               MOS Score
             ~Low                                 4.0+

            AP+ Switch                         Meru AP &
          standard Client                   Standard Client

    Data and voice typically on      Converged Network - voice
    Separate channels/network        and data on same channels
      Air Traffic Control Technology
      Service Fairness

Throughput   Standard AP’s + 20 Clients             Throughput   1 Meru AP + 20 Clients

              x   Industry leading aggregate throughput at density
              x   Predictable, uniformly fair throughput across all
                   q   Other AP’s erratic, unfair access over short term
Air Traffic Control Technology
Zero Loss Handoff

         Other WLAN                   Meru WLAN

                                Virtual Cell Architecture

      BSSID = A   BSSID = B       BSSID = M   BSSID = M

                       01:00                       00:00

100ms – 2 sec between handoff   No Handoff For Client
How Over-the-Air QoS Compares

                                                         Air Traffic Control

    Global RF Knowledge and
                                          --                     Yes
    Inter-cell Coordination

    Application Flow Detection   Static ESSID-based or
                                                            Yes (Dynamic)
    and Classification                   Filters

    Admission Control                     --                     Yes

                                  Simple Priority of      Reservation-based
    Downlink (AP to Client)
                                      packets            True over-the air QoS

    Uplink (Client to AP)                 --
                                                         True over-the air QoS
Voice Services Module Further Improves
Users Experience

 x Consists   of the following components:
   q   Call Admission Control
   q   Call Load Balancing
   q   Dynamic Error Correction
Call Admission Control

 x Enables administrator to configure
   system to allow a given number of
   active calls
 x Upon reaching limit, call can either be
   rejected with Network Busy (similar to
   PSTN) or can be moved to alternate
   channel that has available resources
Call Load Balancing
 x   System can perform balancing of the data/voice
     devices across multi-channel deployments in dense
 x   Dynamically re-balance phones during call setup to
     achieve peak call density in an area (3X other
 x   Allows you to paint an area with 3 channels to
     achieve 3X call density allowing you to handle
     common deployment situations where workers
     congregate in a break area or conference room and
     all place calls simultaneously.
Example Load Balancing Within a

x   After initial assignment,
    AP1: 6 STA, AP2: 3 STA        AP1     Channel 1 VirtualCell     AP2
x   Client signal re-evaluated
    every 1 second and moved
    to strongest AP within the
x   Data rate maximized by
                                        After Periodic Load Balancing
    assigning to AP with
    strongest signal as clients
    roam about.
                                  AP1     Channel 1 VirtualCell     AP2
Example Load Balancing Across two
                                 Example Settings:
x   After initial assignment,    Max Stations per AP = 7
    AP1: 7 STA, AP2: 3 STA       Max Stations per VirtualAP = 10
    AP3: 4 STA, AP4: 6 STA
x   Within each VirtualAP,
    the client signal is re-
                                AP1     Channel 1 VirtualCell      AP2
    evaluated over time and
    moved to strongest AP
    within the VirtualAP
    (refer to slide 12).

                                        Channel 6 VirtualCell      AP4
Dynamic Error Correction

 x System   monitors voice flow and when
   loss is detected due to outside
   interference, corrects the loss by
   interpolating the voice sample.
 x Preserves voice quality when
   errors/loss occurs.
Dynamic Error Correction

      Voice Signal Without DEC   Voice Signal With DEC

  RTP voice sample lost
Meru Eliminates Trade-Off Between Backward
Compatibility and 802.11g Throughput
Critical in Voice Client (b) + Data Client (g) Deployments

 UDP                         TCP                         TCP
 1g                          1g                          1g +1b
 (with b clients present)    (with b clients present)    g client perf.

               ~22.6                     ~15.8                    ~10.1

Others          Meru        Others        Meru          Others    Meru

  Source: Meru Lab Tests
 Comparative Results
                                     Meru                                Other Leading AP/WLAN Systems
Density: >3X better                  128 clients/AP                      ~ 15 clients/AP

only product with time fairness

                    UDP (bg mode) 22.6Mbps                               14.8Mbps
50% better in bg    TCP (bg mode) 17.5Mbps                               10.9Mbps
Handoff: 10X – 150X better           2.19ms (in Virtual AP mode)         50ms – 3000ms
                       Spectralink   10 calls/AP; works even with data   8-9 calls/AP in unloaded AP;
                                     clients loaded                      breaks with 2 – 3 data clients
QoS Call Capacity
                      Chariot VoIP   MOS up: 4.22                        MOS up: 1.58            downlink
First truly
                        30 calls     MOS Down: 4.26                      MOS Down: 4.29        kills uplink
                      Convergence    MOS: 4.26                           4 calls did not completedata kills
                       6 calls + 6   Data T’put: 5.6Mbps                 2 calls MOS 1.5            voice
                                                                         Data T’put: 7Mbps
Meru Has Significant Performance Advantage
in Requirements for WLAN Deployments

                    Airespace*        Aruba*       Trapeze*        Meru

                                                                No Client       50 – 150X
           Open     1000-3000**    1000-3000**    1000-3000**
                                                                (2 ms
           WPA         2000         8000 – 9000    2000 ms      switchover in   100 – 400X

802.11g client
throughput, in
                    10.9 Mbps        7.6 Mbps        10.9        17.5 Mbps        1.5X
presence of b

Density of data
                      ~15-20          ~15-20        ~15-20          128            5X

 * Magazine Tests
 ** Depends on client card capabilities
Customer Examples
Hyatt Osaka Hotel
Data and Voice Deployment
                                                         Floor 39
                                                                       IP Centrex
                                                         Floor …        Service
                                                                      Provided By
                                                                      VoIP Service
                                                          Floor 5
x   28 Floors + Conference
    Center                   PDAs
                                                          Floor 4

x   Wireless Data access      WiFi
    for guests               Phones
                                                          Floor 3

x   VoWLAN handsets
    for internal staff                           Conference Floor

                                                      Data Center
x   VoIP carrier providing
    services                          Meru
University of Miami Hospital
Data Application and Voice

                                                       x   Largest Healthcare system in
                                                           Southeast with 6000 member

                                                       x   Multiple applications – data,
                                                           voice, PDA, medical carts,

                                                       x   Meru Benefits:
                                                            q   Ease of deployment
“Meru delivered an easily managed, future-proof             q   Reduced costs
system at a significant cost savings. Its standards-        q   Predictable service with
compliant solution supports Quality of Service for
                                                                over-the-air QoS
real-time applications, single channel operations
for co-channel interference mitigation, and the
ability to seamlessly integrate with our existing
backend infrastructure and security processes.”
- Chris Bogue, IT Director
Meru Selected For World's Largest FMC
Deployments: Validating Meru’s VoIP Wireless
Leadership Position
  x Osaka   Gas: Large Utility
    q   $9B Revenue
    q   50 Offices: 6000+ DoCoMo Dual Mode Phones
    q   Competed with Cisco, NEC and others

  x Large   Construction Company
    q   US$18B annual revenues
    q   Nationwide in Japan, offices in Asia, US, UK
    q   9000+ Dual Mode Phones
Live Shots
Live Shots
Danke / Thank you

To top