Wi-Fi Opportunities In A 4G World
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Wi-Fi Opportunities In A 4G World

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As presented at the 4G Wireless Evolution conference in Miami, January 22, 2010....

As presented at the 4G Wireless Evolution conference in Miami, January 22, 2010.

WiFI has been at the heart of the change to OFDM and MIMO solutions. It is not suprising that WiFi is a hotbed of innovation in today’s marketplace. This discussion looks at the current and future opportunities associated with WIFI and the implications for new kinds of deployment and adaptation by the LTE and WiMAX community.

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  • 1. Current  &  Future  Opportuni.es   for  Wi-­‐Fi  in  a  4G  World   Brough  Turner   rbt@ashtonbrooke.com   broughturner@gmail.com   1  
  • 2. ITU  Vision  for  3G   Global Satellite Suburban Urban In-Building Picocell Microcell Macrocell Basic Terminal PDA Terminal Audio/Visual Terminal 2  
  • 3. “3G”  Services   •  3G-­‐324M  Video  telephony   •  Loca.on-­‐based  services   •  Push-­‐to-­‐Talk    (VoIP  w/o  QoS)   •  Rich  presence  (instant  messaging)   •  Fixed-­‐mobile  convergence  (FMC)   •  IP  Mul.media  Services  (w/  QoS)   –  Video  sharing  (conversa.onal  video  on  IP)   •  Converged  “All  IP”  networks  –  the  Vision   3  
  • 4. “3G”  Services   •  3G-­‐324M  Video  telephony   Limited adoption •  Loca.on-­‐based  services   •  Push-­‐to-­‐Talk    (VoIP  w/o  QoS)   Limited adoption •  Rich  presence  (instant  messaging)   •  Fixed-­‐mobile  convergence  (FMC)   Limited adoption •  IP  Mul.media  Services  (w/  QoS)   Limited adoption –  Video  sharing  (conversa.onal  video  on  IP)   •  Converged  “All  IP”  networks  –  the  Vision   4  
  • 5. “3G”  Services   •  3G-­‐324M  Video  telephony   Limited adoption •  Loca.on-­‐based  services   Bypassed ! •  Push-­‐to-­‐Talk    (VoIP  w/o  QoS)   Limited adoption •  Rich  presence  (instant  messaging)   No traction •  Fixed-­‐mobile  convergence  (FMC)   Limited adoption •  IP  Mul.media  Services  (w/  QoS)   Limited adoption –  Video  sharing  (conversa.onal  video  on  IP)   •  Converged  “All  IP”  networks  –  the  Vision   Too late … 5  
  • 6. The  Internet  is  the  killer  pla[orm     •  Mobile  Internet  access   drives  3G  data  usage   •  Future  business  models  an   open  ques.on   –  Walled  garden  –  too  late  !   –  Adver.sing  ?   –  Other  2-­‐sided  business   models  ?   6  
  • 7. Mobile  Internet  Access   •  For  PC’s  under  restric.ve   terms  of  service,  e.g.     no  servers,  no  P2P,     no  subs.tu.on  for  private   lines  or  frame  relay   •  AT&T:  5GB  @  $60/mo   •  Verizon:  dieo   •  Sprint:    dieo   •  No  US  operator  offers     flat  rate  unlimited  plans   7  
  • 8. iPhone    glimmer  of  what’s  possible   •  Controlled  eco-­‐system   –  Apps  must  meet  unpublished      Apple  &  AT&T  requirements,   e.g.,  VoIP  over  Wi-­‐Fi,  not  3G   •  Explosive  growth  in  mobile     broadband  usage   8  
  • 9. iPhone  traffic   9  
  • 10. US  data  traffic   10  
  • 11. US  3G  performance   •  Novarum  Inc.  (1/2010)   –  Measurements  in    36  ci.es   (Anaheim,  …,  Boston,  …,   Philly,  …,  Raleigh,  …,  Tempe)   –  8-­‐2007:    507/195  Kbps  &   340  ms  delay   –  12-­‐2009:    1.5  Mbps  down   •  Doubling  <  24  months   11  
  • 12. Increasing  capacity   5 Wi-Fi 4 2 Femtocell Internet 1 Operator Services 3 1.  Add Cellsites ($$$) 2.  Newer radios ($$) 4. Femtocells ($$) 3.  More backhaul ($$$) 5. Wi-Fi ($) 12  
  • 13. Spectrum  history   •  1920:    Primi.ve  radio  receivers   –  Needed  to  restrict  who  transmits   13  
  • 14. Spectrum  history   •  1920:    Primi.ve  radio  receivers   –  Needed  to  restrict  who  transmits   •  1927-­‐  1934:    Origin  of  FCC,  spectrum  licensing   –  Ensuing  decades  -­‐  almost  all  spectrum  assigned   –  Three  bands  reserved  for  “junk”  uses   14  
  • 15. Spectrum  history   •  1920:    Primi.ve  radio  receivers   –  Needed  to  restrict  who  transmits   •  1927-­‐  1934:    Origin  of  FCC,  spectrum  licensing   –  Ensuing  decades  -­‐  almost  all  spectrum  assigned   –  Three  bands  reserved  for  “junk”  uses   •  1985:    FCC  authorizes  spread   spectrum  communica.ons  in  the   ISM,  or  “junk”  bands,  i.e.     –  900  MHz,  2.4  GHz,  5.8  GHz   15  
  • 16. Wi-­‐Fi  History   1985   FCC  permits  communica.ons  in  “junk  bands”  at  900  MHz,  2.4  GHz  &  5.8  GHz   IEEE  bodies  iterate;    eventually  publish  first  802.11  spec   1988  -­‐  1997   Three  alternate  solu.ons  for  1  Mbps  opera.on  with  a  2  Mbps  op.on   1999   802.11a  –  54  Mbps  at  5.8  GHz  using  OFDM  modula.on   1999   802.11b  –  11  Mbps  at  2.4  GHz  using  DSSS  modula.on   Wireless  Ethernet  Compa.bility  Alliance  (WECA)  formed   1999   –  Focuses  on  interoperability  and  a  cer.fica.on  program   2001   802.11d  –  extends  the  spec  for  other  regulatory  domains  (EU,  Japan,  etc.)   2003   802.11g  –  54  Mbps  at  2.4  GHz  using  OFDM  modula.on   2003   WECA    adopts  new  name:    Wi-­‐Fi  Alliance   16  
  • 17. 2004  view  of  Wi-­‐Fi  market   17  
  • 18. 2004  view  of  Wi-­‐Fi  market   •  Rampant  growth   however…   •  Ar.cle  in  ‘ The   Economist’  warns   Wi-­‐Fi  under  threat:   •  WiMAX  in  wide  area   •  WiMedia  in  home   18  
  • 19. Addi.onal  highlights   •  1997:    FCC  authorizes  Unlicensed  Na.onal  Informa.on  Infrastructure   (U-­‐NII)  radio  band  providing  200  MHz  more  spectrum  in  5  GHz  band   •  2003:    FCC  adds  255  MHz  to  5  GHZ  bringing  total  spectrum  to  555  MHz   19  
  • 20. Addi.onal  highlights   •  1997:    FCC  authorizes  Unlicensed  Na.onal  Informa.on  Infrastructure   (U-­‐NII)  radio  band  providing  200  MHz  more  spectrum  in  5  GHz  band   •  2003:    FCC  adds  255  MHz  to  5  GHZ  bringing  total  spectrum  to  555  MHz   •  2003-­‐2009:    Task  Group  n  works  to  drama.cally  improve  Wi-­‐Fi     performance,  in  part  via  MIMO  and  Beamforming   •  2007:    802.11n  dray  2  products  cer.fied  by  the  Wi-­‐Fi  Alliance   •  2009:    802.11n  specifica.on  approved   20  
  • 21. Addi.onal  highlights   •  1997:    FCC  authorizes  Unlicensed  Na.onal  Informa.on  Infrastructure   (U-­‐NII)  radio  band  providing  200  MHz  more  spectrum  in  5  GHz  band   •  2003:    FCC  adds  255  MHz  to  5  GHZ  bringing  total  spectrum  to  555  MHz   •  2003-­‐2009:    Task  Group  n  works  to  drama.cally  improve  Wi-­‐Fi     performance,  in  part  via  MIMO  and  Beamforming   •  2007:    802.11n  dray  2  products  cer.fied  by  the  Wi-­‐Fi  Alliance   •  2009:    802.11n  specifica.on  approved   21  
  • 22. In-­‐Stat  (Nov  09)   •  Worldwide  hotspots  reach  245,000  venues  in  2009   •  Hotspot  connects  increased  in  2009  by  47  percent,   bringing  total  worldwide  1.2  billion  connects   •  Wi-­‐Fi  handset  shipments  grew  50%,  2007  to  2008   •  Wi-­‐Fi-­‐enabled  entertainment  device  (cameras,   gaming  devices,  and  personal  media  players)   shipments  projected  to  increase  from  108.8  million  in   2009  to  177.3  million  in  2013   22  
  • 23. ABI  Research  (August  2009)   •  ABI  projects  1  billion  Wi-­‐Fi  chips  in  2011   •  Global  shipments  of  Wi-­‐Fi-­‐enabled  cell  phones   to  double  between  2009  and  2011   –  144  million  in  2009  to  300  million  in  2011   •  90%  of  smart  phones  Wi-­‐Fi  capable  by  2014   23  
  • 24. Increasing  capacity   5 Wi-Fi 4 2 Femtocell Internet 1 Operator Services 3 1.  Add Cellsites ($$$) 2.  Newer radios ($$) 4. Femtocells ($$) 3.  More backhaul ($$$) 5. Wi-Fi ($) 24  
  • 25. Femtocells:    too  liele,  too  late   •  Primary  users  of  3G/4G  data  also  have  Wi-­‐Fi   –  Laptops,  smart  phones   •  Corporate  IT  prefers  Wi-­‐Fi  they  control   •  Consumers  deploying  Wi-­‐Fi  anyway   –  For  PCs,  for  gaming,  for  home  media   –  Pay  extra  to  help  carrier  improve  their  network?   •  Femtocell’s  only  value  may  be  voice  coverage   25  
  • 26. What’s  next?   •  Wireless  .pping  point   –  5  GHz  becomes  as  valuable  as  2.4  GHz  or  700  MHz   –  Spa.al  reuse  →  incredible  density  increments   •  Wi-­‐Fi  leads  the  way   –  Leveraging  Moore’s  law  and  exis.ng  802.11n  spec.   –  Task  Grp  ac  –  Very  high  throughput  <6GHz    (2012?)    New  biz  ops!   26  
  • 27. Spectrum  Myth   TV  Spectrum  is  “beach  front”  spectrum   27  
  • 28. Spectrum  Myth   TV  Spectrum  is  “beach  front”  spectrum   •  Based  on  legacy  technology,  not  physics!   –  Travels  farther  thru  the  air  –  No!   –  Thru  windows  –  roughly  the  same   –  Goes  thru  masonry  –  yes,  this  is  beeer  …   28  
  • 29. Free  space  path  loss   Seems to say more , more loss 29  
  • 30. Free  space  path  loss   Seems to say more , more loss But this equation encapsulates two effects:   Actual path loss   Receiving antenna aperture (assumed to be ½ wavelength) 30  
  • 31. Free  space  path  loss   Seems to say more , more loss But this equation encapsulates two effects:   Actual path loss   Receiving antenna aperture (assumed to be ½ wavelength) 5 GHz photons go just as far as 700 MHz photons ! 31  
  • 32. Refrac.on  and  reflec.ons   Shorter wavelength - more reflections, refraction  “MultiPath”  “Ghosts” if a single receiver 32  
  • 33. MIMO:  Mul.ple  Input  Mul.ple  Output   •  Mul.ple  paths  improve  link  reliability  and  increase   spectral  efficiency  (bps/Hz),  range  &  direc.onality   33  
  • 34. Rich  Indoor  MIMO  Mul.path   Source: Fanny Mlinarsky, Octoscope 34  
  • 35. Municipal  Mul.path  Environment   Source: Fanny Mlinarsky, Octoscope 35  
  • 36. Mul.ple  channels  per  chip   Like  CPU  cores  …   Intel •  2x2  MIMO  –  2008   •  4x4  MIMO  –  2010-­‐11   then   •  8  radios,  16  radios?,  …   Fujitsu how  to  use  silicon?            Be$er  and  be$er                  beam-­‐forming  !   AMD 36  
  • 37. Beamforming   •  Select  among  mul.ple  predefined  antenna  elements   –  Widely  used  with  single  radios  (2G,  3G,  Wi-­‐Fi  –  Vivato,  Ruckus  Wireless)   37  
  • 38. Beamforming   •  Select  among  mul.ple  predefined  antenna  elements   –  Widely  used  with  single  radios  (2G,  3G,  Wi-­‐Fi  –  Vivato,  Ruckus  Wireless)   •  Adap.ve  antenna  arrays   –  Dynamically  compute  phase  and  amplitude  for  each  antenna  element   –  Adapts  for  desired  signal  while  also  reducing  interference   38  
  • 39. Beamforming   •  Select  among  mul.ple  predefined  antenna  elements   –  Widely  used  with  single  radios  (2G,  3G,  Wi-­‐Fi  –  Vivato,  Ruckus  Wireless)   •  Adap.ve  antenna  arrays   –  Dynamically  compute  phase  and  amplitude  for  each  antenna  element   –  Adapts  for  desired  signal  while  also  reducing  interference   8 antenna elements spread over 3.5 λs, i.e. ~18 cm, or < 7.5” at 5.8 GHz 39  
  • 40. Beamforming   •  Select  among  mul.ple  predefined  antenna  elements   –  Widely  used  with  single  radios  (2G,  3G,  Wi-­‐Fi  –  Vivato,  Ruckus  Wireless)   •  Adap.ve  antenna  arrays   –  Dynamically  compute  phase  and  amplitude  for  each  antenna  element   –  Adapts  for  desired  signal  while  also  reducing  interference   8 antenna elements spread over 3.5 λs, i.e. ~18 cm, or < 7.5” at 5.8 GHz 40  
  • 41. Beamforming   ~2014: >300 Mbps Wi-Fi to ~1 Km at mass market prices ? 4x4 MIMO with 8-12 antenna elements 41  
  • 42. Beamforming   ~2014: >300 Mbps Wi-Fi to ~1 Km at mass market prices ? 4x4 MIMO with 8-12 antenna elements 42  
  • 43. Beamforming   ~2014: >300 Mbps Wi-Fi to ~1 Km at mass market prices ? 4x4 MIMO with 8-12 antenna elements 43  
  • 44. Commercial  beamforming    Wi-­‐Fi  beams,  before  silicon  support  …   •  Vivato  (’02-­‐’06)     –  Technical  success,  but  expensive     –  Connect  with  11g  clients  up  to  2  km   –  Vivato-­‐to-­‐Vivato  up  to  18  km   44  
  • 45. Commercial  beamforming    Wi-­‐Fi  beams,  before  silicon  support  …   •  Vivato  (’02-­‐’06)     –  Technical  success,  but  expensive     –  Connect  with  11g  clients  up  to  2  km   –  Vivato-­‐to-­‐Vivato  up  to  18  km   •  Ruckus  Wireless  (today)     –  12  elements  –  selec.vely  switched  to     two  channels  on  2x2  silicon   –  Drama.cally  outperforms  conven.onal   2x2  systems   45  
  • 46. •  11n  wireless  networking  solu.ons  in  silicon   •  Founded  2006;    customers  include  Netgear   •  4x4  MIMO  with  beamforming   46  
  • 47. TVWS  –  Beach-­‐front  Property?   •  MIMO  antenna  element     separa.on  >=  ½  wavelength   –  2.1  meters  at  70  MHz   –  21  cm  at  700  MHz   •  But  only   –  2.5  cm  for  5.8  GHz  Wi-­‐Fi   Ruckus Wireless Wavion Networks D-Link DAP-2553 47  
  • 48. Wi-­‐Fi   3G  /  4G   48  
  • 49. Wi-­‐Fi   3G  /  4G   •  Sta.onary  clients  or   •  Supports  mobile  use     pedestrian  mo.on   at  auto  speeds   49  
  • 50. Wi-­‐Fi   3G  /  4G   •  Sta.onary  clients  or   •  Supports  mobile  use     pedestrian  mo.on   at  auto  speeds   •  Data  centric  (VoIP  an   •  Voice  centric  (voice   ayerthought)   revenues  s.ll  king)   50  
  • 51. Wi-­‐Fi   3G  /  4G   •  Sta.onary  clients  or   •  Supports  mobile  use     pedestrian  mo.on   at  auto  speeds   •  Data  centric  (VoIP  an   •  Voice  centric  (voice   ayerthought)   revenues  s.ll  king)   •  Wide-­‐open  market,   •  4-­‐6  vendors,     many  vendors,  many   1  applica.on,   market  segments,   <700  customers   many  customers   51  
  • 52. Wi-­‐Fi  markets  evolving   •  Well  established  in  enterprises  and  on  campus   •  Mesh  products  emerge  to  fill  coverage  gaps   –  Aruba  Networks,  BelAir  Networks,  Bluesocket,   Cisco,  Clearsite  Communica.ons,  Fire.de,  Locust   World,  Meraki,  Mesh  Dynamics,  Motorola,  Nortel,   Open-­‐Mesh,  Packet  Hop,  Ruckus  Wireless,  SkyPilot   Networks,  Strix  and  Tropos   •  Mesh  node  as  bridge  from  outdoor  to  indoor   52  
  • 53. Muni  Wi-­‐Fi   •  Wireless  broadband  access  networks   –  Take  2;    recovering  from  early  Metro  Wi-­‐Fi   –  Dozens  of  US  ci.es  now  succeeding   •  Ci.es  bring  real  estate,  look  to  save  current  $   –  Communica.ons  for  police  &  other  city  services   •  But  strong  pressure  for  “free”  in  some  form   –  40%  of  APs  are  open  (espc.  Consumer  APs)   53  
  • 54. Varia.ons  on  Free   •  Retail  business  giveaway   –  Coffee  shops,  restaurants,  hotels,  retail   –  Harvard  Sq.  Business  Associa.on   54  
  • 55. Varia.ons  on  Free   •  Retail  business  giveaway   –  Coffee  shops,  restaurants,  hotels,  retail   –  Harvard  Sq.  Business  Associa.on   •  Sponsorship  –  loca.ons,  events   By kumasawa 55  
  • 56. Varia.ons  on  Free   •  Retail  business  giveaway   –  Coffee  shops,  restaurants,  hotels,  retail   –  Harvard  Sq.  Business  Associa.on   •  Sponsorship  –  loca.ons,  events   By kumasawa •  Carrier  supported   –  e.g.  Cablevision’s     Op.mum  Wi-­‐Fi     56  
  • 57. More  free    Ad  supported     •  Didn’t  work  in  2005;  working  now…     –  Costs  way  down;    usage  and  interest  up   •  Freerunr  in  UK      (&  NL,  RS,  ZA)   –  Splash  screens,  limited  dura.on  free  periods,  …   •  JiWire  in  US  –  Ad  pla[orm  for  free  Wi-­‐Fi   –  Used  by  Microsoy  Bing  na.onwide  Wi-­‐Fi  offer   •  Sputnik  in  US  –  Ad  supported  model  growing   57  
  • 58. 100x  mesh  performance  coming   •  Wi-­‐Fi  mesh  performance  has  been  extremely  limited   –  Mul.-­‐path  limited  link  capacity  &  favored  2.4  GHz     –  Single  radios  with  omni  antennas  mean  all  links  share  one     20  MHz  channel,  so  mesh  capacity  drops  ~x2  per  node   58  
  • 59. 100x  mesh  performance  coming   •  Wi-­‐Fi  mesh  performance  has  been  extremely  limited   –  Mul.-­‐path  limited  link  capacity  &  favored  2.4  GHz     –  Single  radios  with  omni  antennas  mean  all  links  share  one     20  MHz  channel,  so  mesh  capacity  drops  ~x2  per  node   •  Pt-­‐to-­‐pt  links  =  drama.c  increase  in  mesh  capacity   –  Direc.onal  antennas  today;    soyware  beamforming  soon   •  Mul.-­‐radio  mesh  nodes   –  Separate  channels  for  each  link;    note:    there  are  eleven     40  MHz  channels  available  at  5  GHz   59  
  • 60. Enterprise  design  adapted  for  BB   60  
  • 61. ILEC  price  umbrella   •  Cost  of  Internet  transit  @  urban  IXPs   –  <$4  /Mbps  /month  (mul.-­‐Gbps  quan..es)   –  <$9  /Mbps  /month  (<=100  Mbps)   •  Elsewhere,  even  1  block  away,  very  expensive   –  T1  $299,  5Mbps  $599,  10  Mbps  $1299  /month   –  This  is  $120-­‐$200  /Mbps  /month      20x-­‐50x  markup   •  Fosters  wireless  bypass   –  WISPs  opera.ng  20%-­‐50%  under  ILEC  price  umbrella   61  
  • 62. Wireless  ISPs   •  >  2000  WISPs,  in  fast  growing  segment   –  Most  use  license-­‐   exempt  spectrum   –  Mix  of     pre-­‐WiMAX,     WiMAX     and,  increasingly,     Wi-­‐Fi  gear   62  
  • 63. Wi-­‐Fi  for  wireless  broadband   •  WISPs  already  use  license-­‐exempt  spectrum   –  Some.mes  with  a  few  licensed  microwave  links   •  11g  &  11a,  rapidly  migra.ng  to  11n  technology   –  Performance  advantage  is  significant   •  Drama.cally  lower  cost   –   5x  or  more  vs  WiMAX  or  pre-­‐WiMAX  systems   –  Increasing  reliability,  similar  performance   63  
  • 64. Ubiqui.  targets  Wireless  ISPs   64  
  • 65. Ubiqui.  targets  Wireless  ISPs   Point-to-point $180-$600 65  
  • 66. Ubiqui.  targets  Wireless  ISPs   Point-to-point Point-to-multipoint $180-$600 ~$240 & $88 66  
  • 67. Example  Wi-­‐Fi  Pt-­‐2-­‐Pt  Link   Ubiquiti BULLET-M5-HP With 28dbi Grid Antenna 802.11n Purchased through distribution: 67  
  • 68. Community  WISP,  Inc.   68  
  • 69. •  Wireless broadband Internet access for all of Brevard County •  Served from 4 locations •  900 MHz, 2.4 GHz & 5 GHz, i.e. all license-exempt spectrum •  30/10 Mbps in many areas •  Expanding into Volusia and Seminole counties 69  
  • 70. Summary   •  Wi-­‐Fi  will  dominate  3G/4G  data  offload   –  Triple  play  operators  already  bundling  “free”  Wi-­‐Fi   –  3G/4G  service  providers  will  follow   •  Eventually,  high  speed  Wi-­‐Fi  will  be  the  norm   –  3G/4G  coverage,  merely  a  fallback   70  
  • 71. Summary   •  Wi-­‐Fi  will  dominate  3G/4G  data  offload   –  Triple  play  operators  already  bundling  “free”  Wi-­‐Fi   –  3G/4G  service  providers  will  follow   •  Eventually,  high  speed  Wi-­‐Fi  will  be  the  norm   –  3G/4G  coverage,  merely  a  fallback   •  Wi-­‐Fi  fosters  resurgence  in  independent  ISPs   –  Wireless  ISPs  offering  wireless  broadband  access   71  
  • 72. Thank  You   Brough  Turner   broughturner@gmail.com   rbt@ashtonbrooke.com    
  • 73. Credits,  References   •  Image  credits,  beyond  those  noted  in-­‐line…   –  Office  building  facade:      hep://commons.wikimedia.org/wiki/User:Beek100   –  Laptop  icon:    hep://www.flickr.com/photos/ichibod/   –  Microwave  oven:    hep://www.flickr.com/photos/code_mar.al/   •  Other  useful  references   –  Novarum  Inc.  measurements:    hep://www.novarum.com/publica.ons.php   –  NIST  Electromagne.c  Signal  Aeenua.on  in  Construc.on  Materials       hep://fire.nist.gov/bfrlpubs/build97/PDF/b97123.pdf   73  
  • 74. 802.11n  in-­‐the-­‐field   •  Ken  Biba:   –  The  King  is  Dead,  Long  Live  the  King:  802.11n  drama.cally  improves  Wi-­‐ Fi  outdoors     –  Real  world  measurements  show  muni  Wi-­‐Fi  networks  outperform   WiMAX  and  cellular     •  Tom’s  Hardware   –  Reviews  Ruckus  Wireless  11n  access  point  with  beamforming,   hep://www.tomshardware.com/reviews/beamforming-­‐wifi-­‐ruckus, 2390.html     •  Net,  net  –  it  really  works!   74