[Tinyos-devel] Re: CTP - day and night

[Omprakash Gnawali]

On Jan 5, 2008 4:32 PM, Philip Levis <pal at cs.stanford.edu> wrote:
>
> On Jan 3, 2008, at 9:16 PM, Omprakash Gnawali wrote:
>
> > I ran CTP for 24 hrs - 4pm till 4pm the following day. The result
> > tagged "aaa9" has been added to this page:
> > http://enl.usc.edu/~om_p/net2/ctp4bitle/figures.html
> >
> > In order to put results from experiments done in the past on the same
> > graphs, I have changed the time scale for the past results. You can
> > read this on the key for the lines on the graph. For example, time * 2
> > means time scaled by 2. The results seem qualitatively similar to aa9,
> > which was the previous long experiment. The numbers are on the top of
> > the page and the graphs follow. I think it would be interesting to
> > understand the cause for loops with aaa9. It would be also interesting
> > to understand the temporal variation in various metrics, including
> > loops. Having data from a 24-hr experiment allows us to study such
> > temporal variations.=
>
> Just to check -- aa9 has the < rule for loop detection, while aaa9
> has the <= rule? There's a big difference in delivery ratio. Also,
> aaa9 has a good number of queue full events... it would be good to
> look into what's causing them. Is it because of how CTP pauses on
> loop detection?
>
> Phil
>

Yes, aaa9 uses the <= test while earlier experiments used the < test.
One of the reasons why the results look more dramatic that they really
are is because of the difference in time scale used in the graphs for
lines corresponding to aa9 vs aaa9.

I just added a figure called cumfullevents(t) which is below the loop
graph to see if there are more full events when there are more loops.
The hypothesis is not supported beyond T=30k. After this point, the
full events taper off but not the loop detections. Something special
happened in the first 8 hrs. I need to look at temporal variation in
delivery ratio - my guess is we are seeing a significantly lower
delivery ratio in the first 8 hrs which explains the 2% difference in
mean delivery ratio over 24 hrs.

Here is the link again:
http://enl.usc.edu/~om_p/net2/ctp4bitle/figures.html

- om_p