Re: [saag] Would love some feedback on Opportunistic Wireless Encryption

Christian Huitema <huitema@microsoft.com> Wed, 26 August 2015 18:52 UTC

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From: Christian Huitema <huitema@microsoft.com>
To: Warren Kumari <warren@kumari.net>, "saag@ietf.org" <saag@ietf.org>
Thread-Topic: [saag] Would love some feedback on Opportunistic Wireless Encryption
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Date: Wed, 26 Aug 2015 18:51:57 +0000
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Subject: Re: [saag] Would love some feedback on Opportunistic Wireless Encryption
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On Wednesday, August 26, 2015 10:36 AM, Warren Kumari wrote:
>
> On Wednesday, August 26, 2015, Viktor Dukhovni <ietf-dane@dukhovni.org>; wrote:
>> ...  This is considerably weaker
>> than many other opportunistic security protocols.  With no protection
>> against a passive adversary who started monitoring before the victim
>> joins the network, is this still worth doing?
> 
> I believe that it is -- I think that the cost to implement this is really really low (I added PoC 
> "support" to OpenWRT in less than an hour, and almost all of that was finding a 
> suitable access point in my basement :-)).
>
> I fully acknowledge that this doesn't solve all issues, and doesn't claim to - but I think that for 
> the negligible cost, the incremental security win is worth it.

You have to decide who you are optimizing for. The administrators would cannot be bothered to set a password for the Wi-Fi? If the router starts doing OWE without their knowledge, there will be a great deal of confusion when legacy UI shows the network as encrypted and users asks the bartender for the password.

So let's assume that OWE is explicitly turned on by the administrators. They take the pain to activate the option in the UI. Why is it simpler than just setting a password? The bartender will still get asked for the password by all the legacy customers, and at that point it does not make any difference whether he has to answer "use the name of the network" or "Open Sesame."

-- Christian Huitema