perfSONAR User Q&A and Other Discussion

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Hi Jason, 

Thanks a lot for your response.

I think the only way for me to move forward would be to look at the second
option you suggested and see how many such mesh measurement instances I can
find. 

Surprisingly none of my look up queries returned the internet2 MA or the Esnet
MA's that you have mentioned.  I guess I need to have a look at my script! 

Thanks
Madhav


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: "LSStore\"]/nmwg:metadata\n";
$hLSXquery .= " let \$metadata_id := 
\$metadata/ 
\n";
$hLSXquery .= " let \$data :=
/nmwg: "LSStore\"]/nmwg: ";
$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