title: changing wireless beacon interval
body: <p>Is there any possible ways to change beacon interval in linux. I have atheros chipset using ath9k driver. I know it is possible to to use iw command to set the beacon interval but still i am confused about the use of the command. Also how do i know the current beacon interval</p>
  
  <p>What i  want is to make a ad hoc networks between two devices using ubuntu 12.04 and beaconing interval lower than the normal values. </p>
  
  <p>This is the output that i get when i run the iw command. </p>
  
  <pre><code>iw iwphy2 set beacon-interval 25
  Usage:  iw [options] command
  Options:
      --debug     enable netlink debugging
      --version   show version (3.2)
  Commands:
      help
      event [-t] [-r] [-f]
      phy
      list
      phy &lt;phyname&gt; info
      dev
      dev &lt;devname&gt; info
      dev &lt;devname&gt; del
      dev &lt;devname&gt; interface add &lt;name&gt; type &lt;type&gt; [mesh_id &lt;meshid&gt;] [4addr on|off] [flags &lt;flag&gt;*]
      phy &lt;phyname&gt; interface add &lt;name&gt; type &lt;type&gt; [mesh_id &lt;meshid&gt;] [4addr on|off] [flags &lt;flag&gt;*]
      dev &lt;devname&gt; ibss join &lt;SSID&gt; &lt;freq in MHz&gt; [fixed-freq] [&lt;fixed bssid&gt;] [beacon-interval &lt;TU&gt;] [basic-rates &lt;rate in Mbps,rate2,...&gt;] [mcast-rate &lt;rate in Mbps&gt;] [key d:0:abcde]
      dev &lt;devname&gt; ibss leave
      dev &lt;devname&gt; station dump
      dev &lt;devname&gt; station set &lt;MAC address&gt; vlan &lt;ifindex&gt;
      dev &lt;devname&gt; station set &lt;MAC address&gt; plink_action &lt;open|block&gt;
      dev &lt;devname&gt; station del &lt;MAC address&gt;
      dev &lt;devname&gt; station get &lt;MAC address&gt;
      dev &lt;devname&gt; survey dump
      dev &lt;devname&gt; mesh leave
      dev &lt;devname&gt; mesh join &lt;mesh ID&gt; [&lt;param&gt;=&lt;value&gt;]*
      dev &lt;devname&gt; mpath dump
      dev &lt;devname&gt; mpath set &lt;destination MAC address&gt; next_hop &lt;next hop MAC address&gt;
      dev &lt;devname&gt; mpath new &lt;destination MAC address&gt; next_hop &lt;next hop MAC address&gt;
      dev &lt;devname&gt; mpath del &lt;MAC address&gt;
      dev &lt;devname&gt; mpath get &lt;MAC address&gt;
      dev &lt;devname&gt; scan [-u] [freq &lt;freq&gt;*] [ies &lt;hex as 00:11:..&gt;] [ssid &lt;ssid&gt;*|passive]
      dev &lt;devname&gt; scan trigger [freq &lt;freq&gt;*] [ies &lt;hex as 00:11:..&gt;] [ssid &lt;ssid&gt;*|passive]
      dev &lt;devname&gt; scan dump [-u]
      reg get
      reg set &lt;ISO/IEC 3166-1 alpha2&gt;
      dev &lt;devname&gt; connect [-w] &lt;SSID&gt; [&lt;freq in MHz&gt;] [&lt;bssid&gt;] [key 0:abcde d:1:6162636465]
      dev &lt;devname&gt; disconnect
      dev &lt;devname&gt; link
      dev &lt;devname&gt; offchannel &lt;freq&gt; &lt;duration&gt;
      dev &lt;devname&gt; cqm rssi &lt;threshold|off&gt; [&lt;hysteresis&gt;]
      phy &lt;phyname&gt; wowlan show 
      phy &lt;phyname&gt; wowlan disable 
      phy &lt;phyname&gt; wowlan enable [any] [disconnect] [magic-packet] [gtk-rekey-failure] [eap-identity-request] [4way-handshake] [rfkill-release] [patterns &lt;pattern&gt;*]
      dev &lt;devname&gt; roc start &lt;freq&gt; &lt;time&gt;
      phy &lt;phyname&gt; set antenna &lt;bitmap&gt; | all | &lt;tx bitmap&gt; &lt;rx bitmap&gt;
      dev &lt;devname&gt; set txpower &lt;auto|fixed|limit&gt; [&lt;tx power in mBm&gt;]
      phy &lt;phyname&gt; set txpower &lt;auto|fixed|limit&gt; [&lt;tx power in mBm&gt;]
      phy &lt;phyname&gt; set distance &lt;distance&gt;
      phy &lt;phyname&gt; set coverage &lt;coverage class&gt;
      phy &lt;phyname&gt; set netns &lt;pid&gt;
      phy &lt;phyname&gt; set rts &lt;rts threshold|off&gt;
      phy &lt;phyname&gt; set frag &lt;fragmentation threshold|off&gt;
      dev &lt;devname&gt; set channel &lt;channel&gt; [HT20|HT40+|HT40-]
      phy &lt;phyname&gt; set channel &lt;channel&gt; [HT20|HT40+|HT40-]
      dev &lt;devname&gt; set freq &lt;freq&gt; [HT20|HT40+|HT40-]
      phy &lt;phyname&gt; set freq &lt;freq&gt; [HT20|HT40+|HT40-]
      phy &lt;phyname&gt; set name &lt;new name&gt;
      dev &lt;devname&gt; set peer &lt;MAC address&gt;
      dev &lt;devname&gt; set 4addr &lt;on|off&gt;
      dev &lt;devname&gt; set type &lt;type&gt;
      dev &lt;devname&gt; set meshid &lt;meshid&gt;
      dev &lt;devname&gt; set monitor &lt;flag&gt;*
      dev &lt;devname&gt; set mesh_param &lt;param&gt;=&lt;value&gt; [&lt;param&gt;=&lt;value&gt;]*
      dev &lt;devname&gt; set power_save &lt;on|off&gt;
      dev &lt;devname&gt; set bitrates [legacy-&lt;2.4|5&gt; &lt;legacy rate in Mbps&gt;*]
      dev &lt;devname&gt; get mesh_param [&lt;param&gt;]
      dev &lt;devname&gt; get power_save &lt;param&gt;
  
  You can omit the 'phy' or 'dev' if the identification is unique,
  e.g. "iw wlan0 info" or "iw phy0 info". (Don't when scripting.)
  
  Do NOT screenscrape this tool, we don't consider its output stable.
  </code></pre>
  
  <p>thanks for your help</p>