Gigabit WiFi: Utilising ac on Campus Considerations and Benefits

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1 Gigabit WiFi: Utilising ac on Campus Considerations and Benefits Paul Lambert Consulting Systems Engineer, UK & Ireland

802.11ac Standard Highlights What s in the 802.

2 802.11ac Standard Highlights What s in the ac Standard Very High Throughput (VHT) - up to 10x compared with11n Wider channels: 80MHz, 160MHz, 80+80MHz (4X) New modulation: 256-QAM (1.3X) More MIMO streams: up to 8 (2X) Well defined Beam Forming Multi-User-MIMO (MU-MIMO) 3

3 802.11ac Data Rate Matrix Data Rates in ac Rates in Mbps 20MHz 40MHz 80MHz 160MHz 1 stream streams streams streams streams streams streams streams Expected in the first generation of silicon 4

36 40 44 48 52 56 60 64 100 104 108 112 116 120 124 128 132 136 140 144 149 153 157 161 165 Wider channels: 80Mhz and 160Mhz 5170 MHz 5330 MHz 5490 MHz DFS Weather radar Not allowed in North America

4 Wider channels: 80Mhz and 160Mhz 5170 MHz 5330 MHz 5490 MHz DFS Weather radar Not allowed in North America 5730 MHz 5735 MHz Not allowed in Europe 5835 MHz IEEE channel # 20 MHz 40 MHz 80 MHz 160 MHz Dynamic Frequency Selection Available Channels for ac Using DFS Channels Without DFS Channels Channel Size US Europe US Europe 40 MHz MHz MHz 1 2 5

5 Data Rate Table Standard Bandwidth Spatial Streams PHY Data Rate Real Throughput a 20 MHz 1 54 Mbps 24 Mbps n 20 MHz 1 65Mbps 46 Mbps n 40 MHz Mbps 210 Mbps n 40 MHz Mbps 320 Mbps ac Phase I 80 MHz 1 293Mbps 210 Mbps ac Phase I 80 MHz Mbps 610 Mbps ac Phase I 80 MHz Mbps 910 Mbps ac Phase II 160MHz Mbps 610 Mbps ac Phase II 160 MHz Mbps 1200 Mbps ac Phase II 160 MHz Mbps 1800 Mbps ac Phase II 160 MHz 8* 6933 Mbps 4900 Mbps * There are no commercial implementations that use more than 3 spatial streams

6 Rate and Range Power and space challenges are still the same Don t expect more than 3 data streams soon (-) Higher rates available at ranges closer to the AP (-) Higher throughput efficiency mean less time (power) spent for transmit (+) Users will still observe greater net throughput (+) Thank You

7 Predicted Uptake Questions?

8 Beamforming Introduced in n n had many options no vendor implemented it ac uses a single standard for beam forming 9

Beamforming By changing time (phase) of 3 transmitters, 802.

9 Beamforming By changing time (phase) of 3 transmitters, ac AP s can create a constructive interference transmit beam-forming waveform (TxBF) and generate a stronger signal that clients can hear better. Without Beamforming 1 st Stream With Beamforming 1 st Stream AP 2 nd Stream 3 rd Stream 11ac AP 2 nd Stream 3 rd Stream Destructive Interference, when three streams of RF energy cancel each other Constructive Interference, when three streams of RF energy stack up each other AP 11ac AP 10

11n 64 QAM coverage Top rate @ 450 Mbps 802.

RX Z(e.g. -90 dbm receiving sensitivity) 802.

10 Beamforming A standard 3x3:3SS n AP effective coverage at different modulation rates Where can I access my Wi-Fi? n 64 QAM coverage Top 450 Mbps n 16 QAM coverage Top 180 Mbps User is outside of RF coverage zone with lowest RX Z(e.g. -90 dbm receiving sensitivity) ac 256QAM 64 QAM Top 1330 Mbps GbE Zone n 64 QAM coverage Top 450 Mbps User is within RF coverage zone with due to reconstructed radio coverage (due to different phase) n 16 QAM coverage Top 180 Mbps

11 Multi-User MIMO Allows a sophisticated AP (#Antennas > #Streams) to maintain high throughput even when the clients are simple (smartphones, tablets, etc ) Up to four simultaneous clients, each with one or more antennas, transmit or receive independent data streams Needs MU-MIMO beam forming support Provides better channel reuse in single channel, enables high client density 4 x density Expected only in the second generation of silicon 12

12 802.11ac Design Considerations Survey/Plan for 5GHz coverage Old AP placements are probably based on old requirements Higher signal strength requirement for 256QAM data-rates 40 or 80MHz Support Highest data rates are only available with 80MHz channels Not all vendors are recommending 80MHz channel widths due to architectural constraints 802.3af/at PoE PD Support Some solutions require 802.3at PoE+ to operate at full performance Multiple GigE ports per AP Worth considering provision, but not a must-have Possible more benefit for resilience than performance 13

13 802.11ac Benefits Higher data-rates than n Gen ac AP s offering 1.3Gbps vs 450Mbps on 11n Greater density Higher data-rates mean clients need less time to complete their data transfers. Leaves more space for more clients Gen 2 AP s will add MU-MIMO capability Better n than n Testing from multiple vendors has shown an increase in performance in n chipsets when used on ac infrastructure - no need to wait for benefits Power consumption benefits on client devices More efficient transmissions lead to lower battery requirements 14

14 Bonjour! A friendly greeting, or death to your network?

doesn t scale due to Location Challenges Which services are relevant

15 Bonjour - Many Challenges Advertisement Problems Bonjour is local only, designed for home use Others use multicast Scalability Issues Bonjour doesn t scale due to Location Challenges Which services are relevant Policy and Control Who should advertise services? Who should learn about services?

16 Policy Policy Service Control in Action (Bonjour) Discover Consolidate Distribute Advertise POLICY CONTROLLED SERVICE DISCOVERY & ADVERTISEMENT

17 Service Control Use Case ESSID: student ESSID: staff Vlan 600 vlan 700 Administration Building Liberal Arts Building 18

18 Service Control - Discovery Global Service Discovery List Liberal Arts Liberal Arts Admin Bldg - Apple TV - Printer - Printer ESSID: student ESSID: staff Vlan 600 vlan 700 Administration Building Liberal Arts Building 19

19 Service Control Policy - Faculty Liberal Arts Liberal Arts Admin Bldg - Apple TV - Printer - Printer ESSID: student ESSID: staff Vlan 600 vlan 700 Administration Building Liberal Arts Building 20

20 Service Control Policy - Student Global Service Discovery List Liberal Arts Liberal Arts Admin Bldg - Apple TV - Printer - Printer ESSID: student ESSID: staff Vlan 600 vlan 700 Administration Building Liberal Arts Building 21

21 Questions???

22 Thank You

Enhancing the Student Experience: SDN Wifi

Enhancing the Student Experience: SDN Wifi Henry Batten UK&I HE/FE Manager hbatten@merunetworks.com By Meru Networks 2014 Customer Acquisition slide (since Q4 2008) Business Highlights Founded in 2002