Re: [dtn-security] Newbie seeking some security related advice

"Graham Keellings (Leonix Solutions Pte Ltd)" <> Thu, 28 May 2009 02:20 UTC

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From: "Graham Keellings (Leonix Solutions Pte Ltd)" <>
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Subject: Re: [dtn-security] Newbie seeking some security related advice
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Armando Caro wrote:
> Ivancic, William D. (GRC-RHN0) wrote:
>> I believe DARPA is using DTN for voice networks but I believe the
>> disruption is expected to be very quick fades and the like or perhaps
>> that voice simply will not make sense at certain times.
> I believe you are referring to the work that BBN is doing for the
> DARPA WNaN program. For this program, we run IP over DTN and use VoIP
> without modifications to the VoIP application. We are using the BPA as
> a forwarding engine that works in both connected and disconnected
> scenarios. VoIP traffic (and other delay sensitive traffic) are only
> routed/forwarded to destinations that are currently connected, since
> VoIP doesn't make sense for disconnected destinations. If a node
> receives VoIP traffic for a disconnected destination, the traffic is
> dropped.
What about "transiently" disconnected nodes? Can we accept loss of
transmission for a fraction of a second? Or even a few seconds?

If I stipulate a network that carries primarily voice traffic (albeit as
VoIP), then what does DTN bring me? I could argue that it adds a degree
of complexity that brings no gain.  I suppose that the gain is that the
network is distributed and has no central infrastructure (although, to
split hairs, that is an ah-hoc network, which not all DTN need to be); I
can see that that would be attractive to DARPA.

> One important take-away from this work... the motivation of DTN is to
> support delay/disrupted scenarios and apps that can operate in that
> regime, but it is possible to implement a DTN stack that can also deal
> with time-sensitive traffic.
> Armando

Thanks very much for taking the time to reply.


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