[OTR-dev] OTR Encrypted File Transfer, Spec Draft

[Hans-Christoph Steiner]

On 06/04/2013 10:27 PM, Hans-Christoph Steiner wrote:
> Nadim Kobeissi
>>
>> Hi everyone,
>> We've been working on the first implementation of OTR file transfer, using
>> the extra symmetric keys afforded in the latest update to the OTR
>> specification.
>>
>> We've come up with a spec draft, you should check it out!
>> https://github.com/cryptocat/cryptocat/wiki/OTR-Encrypted-File-Transfer-Specification
>>
>> Thanks,
>> NK
> 
> Glad to see progress on this.  We're currently debating whether to start with
> this spec, or develop a file transfer method that is in the OTR band rather
> than in the XMPP band like XEP-0047.  Being in the OTR band seems like it
> would provide extra benefits of hiding more meta data, like the fact that a
> file is being transferred, the rough size of the file, etc.
> 
> Having the file transfer happen in the OTR band could provide a fully hidden
> file transfer method by combining things like randomized padding and packet
> size quantization, as well as slaving transfer timing to actual messaging
> patterns or other such ways of hiding the file transfer timing.

Oh yeah, I forgot to mention that OTR in-band might continue to work if a XMPP
service decided to block XEP-0047 transfers.

.hc