Re: [Captive-portals] Comments on draft-nottingham-capport-problem-00

David Farmer <farmer@umn.edu> Tue, 08 March 2016 15:37 UTC

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References: <D2FCEB47.12A6DC%jason_livingood@cable.comcast.com> <CABkgnnV-Nbbt3Mkh-ZOzWig7rJX32SFugkWLnx-t94bA-B__Lw@mail.gmail.com> <E8355113905631478EFF04F5AA706E9830EBCAE6@wtl-exchp-2.sandvine.com> <18C84D29-4E74-463D-B617-5CF25E9DCE7A@mnot.net>
To: Mark Nottingham <mnot@mnot.net>, Dave Dolson <ddolson@sandvine.com>
From: David Farmer <farmer@umn.edu>
Organization: University of Minnesota
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Date: Tue, 08 Mar 2016 09:37:08 -0600
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Cc: David Farmer <farmer@umn.edu>, "Livingood, Jason" <Jason_Livingood@comcast.com>, "captive-portals@ietf.org" <captive-portals@ietf.org>, Martin Thomson <martin.thomson@gmail.com>
Subject: Re: [Captive-portals] Comments on draft-nottingham-capport-problem-00
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While at the same time if we want people to actually use it, a non-HTTP 
solution can't become a trivially easy off-path attack vector or any of 
a number of other security problems either.

I think a non-HTTP solution is critically important, but it's equally 
important to get the security right for all of this, HTTP(S) based or 
not.  This is going to fundamentally be hard to get right, if it was 
easy we would have dealt with this long ago, but now it time to work 
through this and get it right.

Thanks

On 3/7/16 19:24 , Mark Nottingham wrote:
> On 8 Mar 2016, at 2:08 AM, Dave Dolson <ddolson@sandvine.com> wrote:
>>
>> Regarding non-browser clients, even non-HTTP clients, and considering
>> this is the IETF, it seems reasonable to find an IP-layer solution vs.
>> an HTTP-layer solution.
>
> Making the presence of a CP clear to non-HTTP clients seems like a good thing. Doing much more than that (e.g., presenting something to the user, getting their credentials) is less attractive.
>
> Cheers,
>
> --
> Mark Nottingham   https://www.mnot.net/

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