[ndnSIM] Question about ndnSIM for Data Freshness function.

[Prasertsak U.]

*Thank you so much* for all *your help and* suggestion.

Regards,
Prasertsak.


On Thu, Dec 13, 2012 at 10:24 AM, Alex Afanasyev <
alexander.afanasyev at ucla.edu> wrote:

> Hi Prasertsak,
>
> I decided to spend a little bit time today to implement functionality that
> you were missing.
>
> As of the latest commit on github
> (71278d4c6011bf4f961fa79d12a2c39f3fbfdd3c) you can use the following
> content store realizations that fully support Freshness in ContentObjects
> - ns3::ndn::cs::Freshness::Lru
> - ns3::ndn::cs::Freshness::Random
> - ns3::ndn::cs::Freshness::Fifo
>
> (Small disclaimer. I haven't had time to thoroughly test them yet. Basic
> tests working, but if you encounter a bug, please let me know.)
>
> I also updated documentation on the website, adding an example how to use
> new realizations:
> http://ndnsim.net/helpers.html#content-store-respecting-freshness-field-of-contentobjects
>
> Sincerely,
> Alex
>
> On Dec 11, 2012, at 12:44 PM, Alex Afanasyev <alexander.afanasyev at ucla.edu>
> wrote:
>
> > Dear Prasertsak,
> >
> > Though it is possible to specify the freshness parameter in the
> ContentObject packet, ndnSIM does not yet have support for actually
> enforcing it.  Generally, as such a "cache" is just a temporary short-term
> buffer, it does not really matter.  You as a producer don't really have a
> control for how long routers would store your data, similarly how you don't
> have control for how long packets will be in routers interface queues.
> >
> > Actually, Content Store name for the cache in ndnSIM is a little bit
> misleading, and we are planning to rename it to PacketBuffer in near future.
> >
> > It should be pretty straightforward to add freshness functionality
> (similar how it is implemented in ndn-pit-impl.h/cc, but unfortunately I
> will be only available in a week or so to work on this.
> >
> > Sincerely,
> > Alex
> >
> >
> > On Dec 11, 2012, at 5:55 AM, Prasertsak U. <gniliamg at gmail.com> wrote:
> >
> >> Dear cawka (Alex Afanasyev),
> >>
> >> I'm Prasertsak from Thailand. I'm not a native speaker in English. I'd
> apologize if my English made you confuse.
> >>
> >> Now, I'm using the ndnSIM to simulate the CCN network in my research.
> However, I have a problem about "SetFreshness" function on the provider
> side. The data freshness seems to be not working, but I'm not sure because
> of the less experience about this tool.
> >>
> >> This is my simple environment for testing the data freshness:
> >>
> >> Consumer <------------> intermediate node <-----------------> provider
> >>
> >> I try to send the same prefix (i.e., "/data/10") to the provider and
> capture the interest packet at the provider node. Hence, the interest
> packet is replied by the provider application with freshness attributes.
> (Some parts of the code are shown below)
> >>
> >> ndn::ContentObjectHeader data;
> >> data.SetName (Create<ndn::NameComponents> (interest->GetName()));
> >> data.SetFreshness(Seconds(1.0));
> >> data.SetTimestamp(Simulator::Now().GetSeconds());
> >>
> >> At the consumer side, the consumer application tries to send the same
> prefix (i.e., "/data/10") again, but the interest doesn't send through the
> provider after the second time. The response packet came from the cache
> only. In my opinion, the interest packet should send through the provider
> when the data in the cache is expired (by SetFreshness() function ... Is
> correct?).
> >>
> >> My question is
> >>      • Have the ndnSIM supported the data freshness?
> >>      • How to use the data freshness of the ndnSIM? (If the data
> freshness had already supported.)
> >> Thank you very much.
> >>
> >> Regards,
> >> Prasertsak U.
> >>
> >>
> >
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.lists.cs.ucla.edu/pipermail/ndnsim/attachments/20121213/739c9b23/attachment.html>