perfSONAR User Q&A and Other Discussion

[Jason Zurawski <>]

Hi Madhav;

As Victor noted in his response, you may have more luck finding BWCTL 
and OWAMP daemons instead of MPs.  The service author can correct me if 
I am misrepresenting the service - but I do not believe that the BWCTL 
MPs register into the Information Services infrastructure.

Some more comments inline:

On 9/29/10 4:47 PM, 

 wrote:
> Hi All,
>
> I am a graduate student at Georgia Tech and as part of my research work I have
> been exploring  perfsonar deployment and looking to establish the set of
> services I can use.
>
> I am currently interested in performing some on-demand OWAMP measurement
> between a set of nodes in a mesh manner.
>
> I attempted to retrieve the list of access points for OWAMP MP's using the
> following Xquery directed at Home look up services.
>
> my $hLSXquery = "declare namespace
> nmwg=\"http://ggf.org/ns/nmwg/base/2.0/\";\n";;
> $hLSXquery .= "declare namespace
> perfsonar=\"http://ggf.org/ns/nmwg/tools/org/perfsonar/1.0/\";\n";;
> $hLSXquery .= "declare namespace
> psservice=\"http://ggf.org/ns/nmwg/tools/org/perfsonar/service/1.0/\";\n";;
> $hLSXquery .= "declare namespace
> nmtb=\"http://ogf.org/schema/network/base/20070828/\";\n";;
> $hLSXquery .= "for \$metadata in
> /nmwg:store[\@type=\"LSStore\"]/nmwg:metadata\n";
> $hLSXquery .= "    let \$metadata_id := 
> \$metadata/\@id
>   \n";
> $hLSXquery .= "    let \$data :=
> /nmwg:store[\@type=\"LSStore\"]/nmwg:data[\@metadataIdRef=\$metadata_id]\n";
> $hLSXquery .= "    let \$eventType := \$data/nmwg:metadata/nmwg:eventType";
> $hLSXquery .= "    where
> \$metadata/perfsonar:subject/psservice:service/psservice:serviceType=\"MP\"
> and
>                    \$eventType=\"http://ggf.org/ns/nmwg/tools/owamp/2.0\"";;
> $hLSXquery .= "    return
> \$metadata/perfsonar:subject/psservice:service/psservice:accessPoint";
>
> I queried all the home look up services(i retrieved information about HLS from
> the GLS) one by one using the above query.
>
> Through this script I was able to retrieve all the MA's(changed serviceType to
> MA) that support OWAMP data but when I change the serviceType to MP it
> returned no OWAMP MP's. Same was the case when I queried for BWCTL MP's
>
> I looked at the on-demand support in the document
> www.geant2.net/.../PB_perfSONAR_MDM_3.0_20080125103826.pdf and it only
> mentions about on-demand tests being supported for BWCTL (I was however not
> able to retrieve any data on BWCTL MP's as well)
>
> Has anyone been able to retrieve the list of OWAMP and BWCTL MP's ? I am able
> to retrieve the list of
> pinger MP's via the same script. Would I be correct in inferring that OWAMP
> and BWCTL MP's have not seen much deployment?


The pS Performance Toolkit accounts for many of the OWAMP and BWCTL 
daemons you will find in the wild.  The Toolkit does not have an MP 
interface for these services though.  perfSONAR-BUOY is an MA type 
service that will expose measurements on the Toolkit that are being 
collected regularly and would be your best way to find measurements 
between arbitrary endpoints.


> I basically want to be able to monitor the rtt and loss between the set of
> nodes. Is there some other service in perfsonar besides OWAMP which I can use
> to get the same data, considering the lack of OWAMP MP deployment.
>
> If you guys can provide me pointers on how I can accomplish what I am looking
> to do I would be great-full


I think you can try to get what you are looking for in one of two ways:

1) use perfSONAR-BUOY to set up your own tests from a central point 
(perhaps at Georgia Tech) to the daemons that you find via the 
information services.  This would not be a full mesh, but would be a start.

2) Rely on perfSONAR-BUOY instances that may have the measurements 
available that you are looking for.  For example Internet2 and ESnet 
perform regular mesh testing between points on the backbone networks. 
If you can find the MAs for each deployment (e.g. Internet2's = 
http://ndb1.net.internet2.edu:8085/perfSONAR_PS/services/pSB, ESnet's 
has several, and they can be found in the Information services) you will 
be able to get data for different paths.

Hope this helps;

-jason

> Thanks!
> Madhav