Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Principles of High Performance Wi-Fi Brian Mason Director of Product Marketing Brian Mason Director of Product Marketing

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 2 Wi-Fi Needs High speed connectivity for fast transfer of large data files (e.g. CAD, simulation software, etc) Robust coverage for reliability on mission critical projects Pervasive availability for easy collaboration any where. Reliable enough to be considered suitable failover for wired networks Secure connectivity to entrust proprietary data

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Wi-Fi Nightmares 3

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Wi-Fi Nightmares 4

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Wi-Fi Nightmares 5

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 6 Wi-Fi Challenges 1.Higher User Density 2.Performance 3.Reliable Seamless coverage 4.Security 5.Resiliency

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 7 Wired Faced same problem 15 years ago Added bandwidth – Ethernet trumped ATM and Token Ring Dedicated Resources – Switches beat hubs Intelligence at the edge – Intelligent switches are the standard Easier Deployment – more ports, fewer devices

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 8 Wireless Following Wired’s lead Six Trends in wireless making this possible: 1. Standardization of n (Increased Bandwidth) 2. Move from 2.4GHz to 5GHz (Increased Bandwidth) 3. Multi-Radio devices (Greater Capacity) 4. Directional Antennas (Greater range, fewer devices) 5. Embedded Threat Sensors (Increased Security) 6. Integrated Spectrum Analyzer (Easier Troubleshooting)

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Should be ratified June 2009 Faster Up to 100 Mbps with first-gen pre-N products Up to 300 Mbps with n draft 2.0 products Ample bandwidth makes it easier for a single WLAN to support a mix of voice, video and data Farther More than 300 feet vs. 100 feet with a/b/g Potential for lower infrastructure costs because fewer access points (APs) required to blanket an area n: The Basics

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved More Robust MIMO technology mitigates interference and maintains broadband performance even with weak signals More Secure Wi-Fi Alliance certified n draft 2.0 products must include Wi-Fi Protected Access 2 (WPA2) n: The Basics

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved n – Obtaining Higher Data Rates Spatial Multiplexing Source data stream split and sent over separate antennas at the same time Recombined at receiver using MIMO signal processing Doubles, triples, or quadruples the data rate depending on the number of transmit antennas used Channel Bonding Increasing the Bandwidth Bonds two 20MHz channels to a 40MHz channel Slightly more than doubles the bandwidth Phased channel operation: ability to jump between 20 and 40Mhz channels

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved n – MAC Improvements Reducing Overhead Improves Efficiency Frame Aggregation Block ACKs Reduced Inter-frame spacing

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved n Range and Data Rates Longer Range or Higher Data Rates Wi-Fi Certified data rates 300Mpbs Most compatible with a Backwards compatible with bg Channel Bonding Multiple Input/ Muliple Output (MIMO) Spactial Multiplexing

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 14 5GHz vs 2GHz Spectrum

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Channels – Cell Planning b/g Channels Available = 3 Distance to cell with same channel is less than a single cell Sensitive to co-channel interference (from other cells on the same channel) If energy is weak, seen as interference If energy is strong, stations will defer Bleed-over retards higher data rates Greatly reduces overall network capacity a Channels Available = 23 High Performance: 8 times the capacity Far less interference from cells on same channel More channels to avoid interference

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Channels – Interference Issues b/g uses the 2.4 GHz ISM band Common devices cause interference Bluetooth devices Cordless phones Microwave ovens X10 wireless video cameras HAM radio operators Interference collides with the intended signal Transmissions are garbled and data packets are retransmitted Reduced end-user throughput and increased latency of data traversing the RF network a uses the 5GHz UNII band Relatively interference free

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved n Rates and Modes a/n (5GHz) 23 channels * 150Mbps = 3.4Gbps a (5GHz) 23 channels * 54Mbps = 1.2 Gbps g/n (2.4GHz) 3 channels * 150Mbps = 450 Mbps g (2.4GHz) 3 channels * 54Mbps = 162 Mbps b (2.4GHz) 3 channels * 11Mbps = 33 Mbps 150

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 18 Multi-Radio vs Dual-radio Architectures Multiple Radios in a single AP (i.e. an Array) = MORE CAPACITY - Traditional APs have one or two radios - New multi-radio architectures have up to 4, 8, or 16 radios in a single device - Each radio has fixed bandwidth - Each radio can support a limited number of users at one time In a classroom of 30 students a dual radio AP will have 15 students per radio Traditional AP: Multi-Radio In the same classroom an Array would just have 2 or 3 students per radio

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 19 Directional vs Omni-Directional Directional Antennas = GREATER RANGE Better antenna gain Better receiver sensitivity Allows fewer devices cover a larger area Typically 75% fewer devices and cable drops required

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 20 Distributed vs Centralized Distributed = HIGHER PERFORMANCE Packet Processing at edge Control plane at edge Policy and security enforcement at edge Encryption processing at edge Just like Ethernet Switching Central management Central Controller + Thin Aps Packet Processing at core Control plane at core Policy and security enforcement at core Encryption processing at core Central management Centralized ProcessingDistributed Processing

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Security Security Performance Use Line-rate Hardware Based Encryption AES (WPA2) is Best Hardware based encryption on client Best to Use a Single Encryption Mode per SSID Authentication: 802.1X RADIUS Servers should be local PMK Sharing = faster roaming Intrusion Detection Threats, Attacks, Compliance Neighboring Networks Requires: Dedicated Radio for RF Monitoring Time sharing radios for IDS reduces performance especially for voice You cant fix a problem if you don’t know there is a problem 21 Access Point / Array Authentication Server Ethernet Switch Hardware-Based Line-Speed Encryption Encryption Engine Dedicated Monitor Radio

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Wi-Fi Array The Xirrus Wi-Fi Array Single Device Superior Range and Capacity 75% Less Devices and Cabling Up to 16 Modular Radios n Upgradeable Advanced RF Management Redundant Radios and Ethernet Integrated Wi-Fi Switch Integrated Spectrum Analyzer Integrated Threat Monitor Line Speed Hardware-based Encryption Filtering and Firewalling Complete Suite of Management and Planning Tools Plan for the Success of your Wi-Fi Network! 22 Wi-Fi Sponsor ’06 & ‘07 Best Design of the Year B e s t S t a r t u p Array Controller Radio Modules Antennas

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved 23 The Future of Wi-Fi “The only effective way to deliver high- performance Wi-Fi is to have a centrally managed intelligent edge network – just like your wired networks do”

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Wi-Fi Reference Poster Series Xirrus Wi-Fi Reference Posters Register at: Posters in the Series a/b/g n Principles Wi-Fi Authentication Wi-Fi Encryption Wi-Fi Range Dynamics Wi-Fi Network Architectures Wi-Fi Cousins & Nephews High Performance Wi-Fi Also: Reference Poster Podcast Reference Poster Companion Guides Webinars White Papers Design Guides

Confidential Information ® 2008 Xirrus, Inc. All Rights Reserved Thanks Visit forwww.xirrus.com - Wi-Fi posters n webcast and podcast - Best Practices and design guides - Wi-Fi gadgets and widgets