[LINK] Google's WiFi bungle

David Vaile d.vaile at unsw.edu.au
Wed May 19 17:25:02 AEST 2010

> Date: Wed, 19 May 2010 07:22:41 +1000
> From: Stilgherrian <stil at stilgherrian.com>
> Subject: Re: [LINK] Google's WiFi bungle
> Personally I don't think mapping the SSIDs of Wi-Fi networks is a breach
> of privacy, since it IS broadcast information and it isn't personally
> identifiable in and of itself. 

Hi Stil, 

"Broadcast": While WiFi uses radio, and for some purposes you could use the term 'broadcast' for everything that emits an electromagnetic wave, there is a category problem here. 

'Broadcasting' in this narrow physical propagation sense is being conflated with 'broadcasting' in the other broader sense, of being deliberately offered to all, in a context intended to be widely available. This other assumed meaning is then used to infer that home WiFi network operators (and their users?) should be deemed to have implicitly given permission for eg., Streetview to take whatever it can get from this transmission. 

The law in Australia, as I mentioned, clearly treats WiFi as NARROW-casting, intended for certain specific (intended) users, NOT for everyone. It is thus NOT a 'broadcast' like say a commercial radio station is a 'broadcast', even though they both use electromagnetic waves. 

WiFi is legal here only if operated under a specific Low Interference 'class licence' offered on the basis that, while it uses radio spectrum also used elsewhere by others, there is very limited prospect of interference -- largely because the range of the device is strictly limited by a very low wattage power, and few others will be able to receive it. This Narrowcast regulatory model is another basis for why it is reasonable for technically unsophisticated users (most of us) to treat WiFi as different from say operating your own radio station, even ham radio. By specific regulatory requirement it is restricted to be very local and short range, and is often difficult to receive even in the same building because of these power limits (though less so with newer N protocols).

You of course can boost range and reception using various fun techniques, but these run the risk of falling outside the class licence precisely because they may affect/be receivable by many others -- such as by combinations of antenna gain and transmitter wattage that exceed the low Australian effective limits.

The Streetview collection only worked because their receivers physically came within the very limited, more or less domestic range of devices, like a global-scale house to house 'war drive'. The equivalent of bouncing an infrared beam off house windows to eavesdrop conversations inside. 

Possible: yes, legal: maybe not, authorised: no.

The proper response here may be user education, and perhaps even specific legal protection against unauthorised harvesting of narrowcast network data (if it does not already exist within the federal Criminal Code, the Cybercrime Act 2001 or the Telecommunications Interception Act), not saying 'anything goes' because it is physically possible, and clueless users are not aware they need to guard against it using more than default security.


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