AdSense

Sunday, October 16, 2016

WI-FI PT / 2 - ATTACKS AGAINST INFRASTRUCTURE / 2.8 - Working at disallowed channels and exceeding power output limits


2.8 - Working at disallowed channels and exceeding power output limits

- Because every country in the world has got its own legislation regarding to the radio spectrum, it is important to know which are the channels and output power allowed in every place. Moreover, each wireless network interface has got its own default regulatory settings.  
- First of all, assuming we are in the United States (US), let's take for instance the US regulatory domain:



- This new setting is immediately detected by the log file of the system:



- In the US regulatory domain is perfectly possible to use channel 11:



- But it is not allowed channel 12:



- About the power output, maximum allowed is 27 dBm (500 mW):



- For that reason, 30 dBm ( 1 Watt) is rejected:



- Now, although being physically in the US, the regulatory domain can be changed, for instance to Bolivia (BO):



- Again, the log file records the news:



- Now, the system allows to use both channel 12 (2.467 GHz) and power 30 dBm (1 Watt), because Bolivian regulatory domains are different from the US:



- What to do for using the all over the world forbidden channel 14? the answer is to change to Japanese regulatory domain, because Japan is the only country in the world allowing channel 14:



- The log informs about the changes:



- Verifying that the wireless interface card is now working at the forbidden channel 14 (2.484 GHz):



- From this practice, we conclude that although in each country there are unlicensed wireless bands and strict power limits specified, all those regulations can be overwritten changing the regulatory domain to other country. In this way, the wireless interface card is forced to work at:
  • disallowed channels
  • more than allowed power transmission