[Nfd-dev] A question about data return pathways

[Anthony Dowling]

Junxiao,

Thanks for your help, that answers my question completely.

Anthony Dowling

On Tue, Mar 13, 2018 at 2:19 PM, Junxiao Shi <shijunxiao at email.arizona.edu>
wrote:

> Hi Anthony
>
> what happens to the PIT entry when a data packet comes back to NFD through
> the same face that the interest came through?
>
> The Data packet would satisfy the PIT entry. A node does not care whether
> an a Interest was forwarded out of the face receiving Data.
> Cough cough: you can use this property to for cache poisoning, by sending
> an Interest followed by a Data satisfying that Interest. In reality it
> works if you timed your packets right.
>
> I have a configuration where there are two unicast UDP faces, and an
> interest comes from one of them (face A) and then gets relayed to the other
> face (face B). If data for that interest is returned to NFD through face A,
> what happens to it?
>
> The Data satisfies the PIT entry. The node does not forward it out of face
> A, because there is only one neighbor node on this face, and the Data comes
> from that neighbor.
>
> Would there be a way to have the data be routed to face B for delivery to
> other devices, rather than simply disappearing?
>
> Yes, the node connected to face B needs to express an Interest.
>
> Yours, Junxiao
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.lists.cs.ucla.edu/pipermail/nfd-dev/attachments/20180313/a03a3b4c/attachment.html>