[ndnSIM] how to obtain link load

[Alex Afanasyev]

Hi Shenglan,

Got it.  I think for your specific case you should not use tracer at all, since it is really designed for recording simulation scenario metrics, and not to be used internally.

For the "instant" link load (besides that you have to carefully define "instant"), there are no modules in the base code of ndnSIM, but I made an extension to obtain run-time statistics per interface/per name prefix about incoming/outgoing interest/data packets as part of Interest flooding mitigation research.  It may be not exactly what you need, but you can try to modify it for your needs.  

You can check the code in this repo on github: https://github.com/cawka/ndnSIM-ddos-interest-flooding
The files that you will be interested are:
- extensions/stats.h and extensions/stats.cc  defining a "forwarding strategy" (actually it is a strategy layer) that tracks in real-time NDN stats and records it in a special data structure
- extensions/stats/*  implementation of this special data structure.

Let me know if you have questions.  I wasn't sure that this "module" (and this particular implementation) is general enough to be included in ndnSIM code base, but if you find it useful, I can push it to the base.

---
Alex


On Apr 16, 2013, at 12:00 AM, 陈胜蓝 <blindeafer at 163.com> wrote:

> Yes，I got the "rate-trace.txt" and "aggregate-trace.txt".
> 
> I want to write a caching scheme that nodes implement it according to both the instant input link load when they got a contentobject and the output link load according to PIT entry(s).
> 
> Would please provide me an example on how can a node get the instant link load and make use of the instant value to decide whether to cache the contentobject?
>  
> 
> 
> 
> 
> At 2013-04-16 01:29:26,"Alex Afanasyev" <alexander.afanasyev at ucla.edu> wrote:
> Hi Shenglan,
> 
> Have you tried ndn::L3RateTracer (http://ndnsim.net/metric.html#example-of-packet-level-trace-helpers)?  It breaks down the "rates" (and the aggregate number of packet/bytes) for incoming and outgoing data/interest packets, as well as faces on which (to which) data/interest packets were send out.  You can just run the example and check the contents of rate-trace.txt file.
> 
> ---
> Alex
> 
> On Apr 15, 2013, at 2:29 AM, 陈胜蓝 <blindeafer at 163.com> wrote:
> 
>> Hi Alex,
>> 
>> Is there any module to obtain the link load of the link from which a content object come into a node and the link(s) which a node transmit to according to PIT entry(s)?
>> 
>> Best regards,
>> Shenglan
> 
> 
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.lists.cs.ucla.edu/pipermail/ndnsim/attachments/20130416/686e6a27/attachment.html>