2.4GHz  is  Dead:  Abandoning  the  2.4GHz  ISM  Band  for  Greener  Wi-­‐Fi  Pastures  

At  Least  on  Life  Support..  

Dead  Like  PIFS  

•  PenetraDon  –  2.4GHz  has  4.3X  beGer  penetraDon  in  open  space  than  5GHz  

•  Interference  – Modulated  and  unmodulated  devices  –  Too  many  devices  on  a  channel  raises  the  noise  floor  

•  Frequency  Space  –  3  non-­‐overlapping  channels  – No  wide  channels  possible  –  Bounded  on  top  and  boGom  by  licensed  bands  

PenetraDon  

2.4GHz  penetrates  open  space  4.3X  beGer  than  5GHz  

2.4GHz  

5GHz  

Too  much  penetraDon  (limits  channel  reuse)  

Interference  

Too  much  interference  in  the  band,  and  quickly  geVng  worse  

IoT  brings  with  it  30+  Billion*  always-­‐on  devices  and  200+  Billion  intermiGently-­‐connected  devices  by  2020.    Many  of  these  devices  will  use  2.4GHz  (Bluetooth,  Zigbee,  Wi-­‐Fi).  

*Sources:  Gartner  &  IDC  

Frequency  Space  

2.4GHz  supports  3  non-­‐overlapping  channels  

Not  enough  channel  space  (limits  channel  reuse)  

Noise  Floor  Whether  hundreds  of  probing  Wi-­‐Fi  staDons  or  wideband  interference,  if  the  noise  floor  is  high,  performance  will  be  poor.  

Importance  of  Channel  Reuse  

•  ApplicaDon  Performance  •  System  Capacity  •  User  Experience  

Co-­‐Channel  ContenDon  (CCC)  Football  Field  (120  Yards,  110  Meters)  PerspecDve:    1mW  (0dBm)  in  open  space  

Receive  SensiDvity  Many  of  today’s  Wi-­‐Fi  chipsets  have  Rx  SensiDvity  below  the  actual  noise  floor  at  low  data  rates.  

Move  CriDcal  Wi-­‐Fi  to  5GHz  It’s  common  that  5GHz  channels  are  either  unused  or  lightly  used  

5GHz  by  Contrast  

Source:  Wireless  Training  &  SoluDons  

25  non-­‐overlapping  channels,  with  12  more  proposed  by  the  FCC  

What  Now?  •  Move  to  5GHz,  now.  OpDmize  for  performance.  •  Use  channels  supported  by  your  client  devices.  •  Move  client  devices  to  5GHz  11ac  when  possible.  •  Do  not  buy  2.4GHz-­‐only  client  devices  of  any  kind.  •  Use  a  performance-­‐opDmized,  transiDonal  2.4GHz  SSID  •  Set  organizaDonal  policy  to  avoid  use  of  2.4GHz  •  Set  expectaDons  for  2.4GHz  users  (whether  corporate  or  BYOD)  

•  Monitor  the  2.4GHz  spectrum  at  L1  &  L2  (WIPS)  

Time’s  Up!  

Learn  more  in  my  new  white  paper:    h"p://divdyn.net/docs/2.4-­‐GHz-­‐is-­‐Dead-­‐v1.00.pdf