perfsonar development work

[Nicolas Simar <>]

Hi Stig,

just to mention you that few days ago, I met people from Renater and from
the French regional network. They mentioned that they are interested by
a monitoring tool that allow them to identify where a multicast problem
is located.

They had an issue between them and an Asian network. A multicast UDP
transfer which was experiencing packet loss. The Asian network NOC was
troubleshooting the problem with ICMPs and was identifying a certain
amount of packet loss within the Regional network. The regional network
wasn't seeing any packet loss locally and identify TEIN2 diagnoses as
rather being an accumulation of packet loss over GEANT2-Renater.

There was no tool available to clearly identify where the problem was
located (on which section of the network) and no way of exchanging that
information between network in a trusted and meaningful way (both
parties understanding the test done).

I believe that what you describe as
"Another possibility is that the join path is in place, but that the
data is not forwarded all the way to the receiver. This is also
something that would be checked thruogh the MP multicast service. If
receiver receives some data but not all, the tool could also tell where
packets are being dropped along the path. "
would allow to identify the location(s) where the packets are being
dropped. Would it be at an AS level or at a router level that those
detection would occur?

Cheers,
--
Nicolas
______________________________________________________________________

Nicolas Simar
Network Engineer

DANTE - www.dante.net

Tel - BE: +32 (0) 4 366 93 49
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