David Black President/CEO Insource Technology Corporation (281) 774-4150 david.black@insource.com www.insource.com
Interested in Wireless LANs? There's no shortage of advice A lot of it is incomplete, biased, and sometimes just flat-out wrong Manufacturers Trade press Self-proclaimed experts
The Current State Wi-Fi has shifted from convenience to essential Experiencing explosive growth Wi-Fi traffic will exceed wired traffic in 2015 30 B 2020 1.9 billion Wi-Fi devices will be in use in 2014 No sign of slowing down
802.11 Fundamentals Public spectrum Free, anyone can use Interference is common Shared Medium Half-duplex One talker at a time
802.11 Fundamentals The station is the boss Different NICs Different drivers Different behaviors Collision avoidance Requires a lot of overhead
Two Frequency Bands 2.4 GHz Greater range 802.11b/g/n devices Heavily congested 3 non-overlapping channels in the U.S 5 GHz Greater performance 802.11a/n/ac Shorter range 9-22 non-overlapping channels in the U.S.
Keys to Success Good design Good equipment Good installation/configuration
Good Design Design coverage for 5GHz More channels Less Interference Better Performance Minimum RSSI: -63dBm or better Minimum SNR: 25dBm 2013 Insource Technology Corporation
Good Design Design for Capacity (not just coverage) Number of users and types of devices Desired bandwidth per user Add enough APs to provide needed capacity One AP for every two classrooms 2012 Insource Technology Corporation
One AP per Classroom? Someday, but not yet Buy what's required for today Buy more in the future when needed Better radios Higher performance New features Lower cost
As AP Density Increases So will Co-Channel Interference Contention from APs on the same channel Destroys network performance A good design can help minimize Careful placement of APs Taking advantage of building obstructions and distance Optimized transmit power
Good Equipment Wireless infrastructure Wired network Cable plant
Good Equipment Use real commercial grade access points Designed to work as a system Better radios, multiple radios, more control over the radios Multiple SSID's, User Roles, VLANs More powerful hardware Plenum rated Power over Ethernet Intrusion detection functionality Broader selection of antennas Auto-channel and auto-power Band steering, load balancing, airtime fairness
Good Equipment Carefully test critical features Good Load Balancing Airtime Fairness Band Steering Bad Receive Sensitivity Performance under max load Power consumption
Edge Switch Considerations Power consumption is not the problem it once was but... Many 3-stream APs require 802.3at for full functionality Vendor excuses vary significantly Insist on written specs and test for compliance Using standard POE with a 328 ft. cable, will your AP sustain full functionality while under maximum load? If "yes" show me
Edge Switch Considerations Are Gig switches sufficient for 802.11ac access points? Yes, not only for Wave-1 APs but Wave-2 as well Wave-1 Max PHY if only 3-stream 11ac devices present Approximate TCP Typical TCP on a well designed network Typical TCP if only 2-stream 11ac devices present TypicalTCP if only 2-stream, half-up / half-down Rate 1.3Gbps 650K 500K 333K 167K
Edge Switch Considerations Are Gig switches sufficient for 802.11ac access points? Yes, not only for Wave-1 APs but Wave-2 as well Wave-2 Max PHY if only 4-stream Wave-2 devices present Approximate TCP Typical TCP on a well designed network Typical TCP if only 2-stream 11ac devices present TypicalTCP if only 2-stream, half-up / half-down Rate 1.7Gbps 867K 650K 430K 215K
Cable Plant Considerations 5e is OK if that's what you have, but Cat 6 is recommended Cat 5e Cat 6 Cat 6a Ratedfor 1G 1G / 10G 1G / 10G Max length 1G / 10G 328 / NA 328 / 180 328 / 328 Relative Cost / 1000 ft 1x 1.3x 2x Other Size Weight Bendradius
Good Equipment Don t let vendors distract you with sideshows and gimmicks Layer 7 functionality Cloud-based and controllerless architectures Integrated spectrum analysis Stay focused on what's most important to users Wi-Fi performance, stability, reliability
Good Configuration Use 5GHz as the Primary Network Operate in HT or VHT modes Force legacy 11a clients to 2.4GHz band Enable Dual-CTS if nearby 11a networks exist Consider reducing channel width in high-density areas if necessary Consider enforcing minimum connection rates
Good Configuration Use 2.4GHz for Legacy Devices Operate in HT-Mixed mode Use 20MHz channels only Disable PCO Disable 802.11b rates Enforce minimum connection rates
Wi-Fi Security Employee Network: WPA2-Enterprise Domain computers, full access Personal devices, internet only (generally) Use roles instead of multiple SSIDs Guest Network: PSK, open, or captive portal, internet only Upgrade older hardware that doesn't support WPA2 Disable ad-hoc connections
Sample Wi-Fi Security Configuration PDF Version DOMAIN COMPUTERS 802.1X Hidden Domain Computers GPO Config PERSONAL / UNMANAGED 802.1X Visible Employee Personal Devices Enter Credentials First Time GUESTS Open, PSK, Captive Portal Internet Only Full Access Internet (+ Print) Role 1 Role 2 Role 3 Role 1 Role 2 Role 3 ACL ACL ACL ACL ACL VLAN VLAN VLAN VLAN VLAN Operating Hours Operating Hours Operating Hours Operating Hours Operating Hours Location(s) Location(s) Location(s) Location(s) Location(s) Rate Limits Rate Limits Rate Limits Rate Limits Rate Limits NAP Policies
802.11 Standards 3500 3000 2500 2000 1500 1000 500 802.11n 2 Streams 300 Mbps 802.11 Roadmap 802.11n 3 Streams 450 Mbps 802.11n 4 Streams 600 Mbps 802.11ac Wave 1 3 Streams 1.3 Gbps 802.11ac 2 Streams 867Mbps 802.11ac Wave 2 3 Streams 2.6 Gbps 802.11ac Wave 2 4 Streams 3.5 Gbps 802.11ax 3.5Gb/stream APs with More transmitters More receivers More streams Better MU-MIMO 3 Streams 10.4 Gbps 4 Streams 13.8 Gbps 0 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 "802.11 timeline"
802.11ac Many benefitsover 802.11a, b, g, n Higher data rates More capacity Longer range More reliable Significantly more complex The benefits and the complexity come from a long list of enhancements
Major Enhancements in 802.11ac More advanced modulation and encoding Wider channels More spatial streams Multi-user MIMO Transmit beamforming
Understanding 802.11 PHY PDF Version 802.11 a/g PHY Rate 20 MHz wide channel 52 subcarriers (48 data, 4 pilots) -10MHz f c 52 Subcarriers (48 usable) +10MHz 6 bits encoded per sub-carrier -10MHz Data Data f c Data EC +10MHz 3 / 4 forward error correction 75% of bits are data Symbol (216 data bits) 250,000 symbols/sec 48 x 6 x 0.75 = 216 x 250,000 = 54 Mbps
Understanding 802.11n PHY PDF Version 802.11 n PHY Rate 40 MHz wide channel 114 subcarriers (108 data, 6 pilots) -20MHz f c 114 Subcarriers (108 usable) +20MHz 6 bits encoded per sub-carrier 5 / 6 forward error correction -20MHz f c +20MHz Data Data Data Data Data EC 83.33 % of bits are data Symbol (540 data bits) 277,777 symbols/sec 108 x 6 x 0.83 = 540 x 277,777 = 150 Mbps
Understanding 802.11ac PHY PDF Version 802.11 ac PHY Rate 80 MHz wide channel 242 subcarriers (234 data, 8 pilots) -40MHz f c 242 Subcarriers (234 usable) +40MHz 8 bits encoded per sub-carrier 5 / 6 forward error correction -40MHz f c +40MHz Data Data Data Data Data EC 83.33 % of bits are data 256-QAM Symbol (1,560 data bits) 277,777 symbols/sec 234 x 8 x 0.83 = 1,560 x 277,777 = 433 Mbps
Wave-1 vs Wave-2 and Beyond 5GHz Only 256-QAM Modulation 20/40/80 MHz Channels Wave 1 (2013-2014) 160 and 80+80MHz Channels -- Wave 2 (2015) Future Max Number of Streams (APs) 3 4 8 Max Number of Streams (Clients) 3 4 4 MU-MIMO (APs) -- 2Q MU-MIMO (Clients) -- 3Q
PDF Version Multi-User MIMO Transmit to multiple stations simultaneously Improves network efficiency TxBF one stream to client 1 using transmitters 1 and 2 Downstream only Requires Wave-2 on both ends Transmit Beamformingon the AP 2 transmitters per stream Physical separation between clients TxBF one stream to client 2 using transmitters 3 and 4
Wider Channels and DFS Wider channels = fewer channels DFS restrictions reduces the number further SAFE APs -NOT RECOMMENDED BRIDGES -OK DFS Generally not supported on Entry level APs Some clients 144 25 9 12 4 62 20 1
More 5GHz Spectrum Coming 25 channels now (22 in U.S.) Gain back 120, 124, 128 (with restrictions) New spectrum for 10-12 more channels Currently available channels New channels Not practical to use in U.S. 20 MHz 40 MHz 80 MHz 160 MHz 36 40 44 48 52 56 60 64 68 72 76 80 84 88 92 96 100 104 108 112 116 120 124 128 132 136 140 144 UNII-1 UNII-2 NEW UNII-2 UNII-3 149 153 157 161 165 169 173 177 181 NEW
802.11ac Caveats Performance is great, but generally less than expected 256-QAM has limited range (~ 20 ft. line of sight) 80 MHz channels are difficult to sustain in dense deployments 3-stream APs may require 802.3at POE for full functionality Legacy protection mechanisms will impact performance Entry level APs and some client NICs don't support DFS
802.11ac Recommendations If it's time to upgrade, go with 11ac Today's 3-stream 11ac APs are an excellent value If you can't justify 3-streams Consider lower cost 2-stream 11ac APs Or even lower cost entry level 11n APs If it's not time to upgrade, wait for Wave 2 and MU-MIMO
Summary Design for 5GHz coverage and for capacity Don't under-provision or over-provision Rein in transmit power Utilize WPA2-Enterprise and user roles Minimize the number of SSIDs Try before you buy
Introduction to Insource David Black Insource Technology Corporation (281) 774-4150 david.black@insource.com www.insource.com
Overview Who We Are Information Technology consulting firm Established in 1992 by the founders of Compaq Clients across the U.S.; projects around the world Short and long-term engagements with clients of all sizes Public, private, for-profit, non-profit, practically every industry
Overview What We Do Enterprise Wireless - Wireless LAN Infrastructure, Intrusion Detection & Prevention, Distributed Antenna Systems, Bridges Enterprise Infrastructure - Storage, Virtualization, Microsoft Lync, Local and Wide-Area Networks, Security Enterprise Applications - SharePoint, Custom Application Development Managed Services
The Insource Difference OUR UNIQUE Value Added Guarantee "Our client has the right to adjust our compensation if the client determines that the value we have added to the assignment is not commensurate with the fee arrangement previously established."
Enterprise Wireless Networks PDF Version We make wireless work Offices, schools, hospitals, factories Indoor Outdoor Problem-prone environments Mesh, bridges, PtP and MP Intrusion detection/prevention systems Top technical certifications with practically all industry leaders
Enterprise Wireless Networks Comprehensive Service Offerings Designs and Surveys Assessments and Tune Ups Toolkits and Training WLAN Controller Video Storage Video Monitor s Security and BYOD solutions IP Camera LAN/WAN Analog Camera Mesh IP Camera Tutorials to help build your organization's expertise WLAN IP Camera Voice Indoors Data WLAN IP Surveillanc Camera e w/ PDA Outdoors
Wireless Tutorial Series 1. Wireless Network Basics 2. Wireless Security 3. Anatomy of a Wireless Hack 4. Survey and Design Tools 5. Advanced Troubleshooting 6. Protocol 101 7. 802.11n Overview 8. 802.11n PHY Enhancements 9. 802.11n MAC Enhancements 10. 802.11ac Hype vs. Reality 11. BYOD and Securing Your Environment
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