perfsonar development work

[Joe Metzger <>]

On Aug 14, 2008, at 3:41 AM, Nina Jeliazkova wrote:
> However, Maciej had a different view ( don't restrict the answer to  
> one subnet, present everything to the user, see emails below ), so  
> we thought it will be best to move the discussion into the  
> developers mailing list.
>
> In summary,  my question is as follows (having in mind only the use  
> case when the user is asking for list of IPs coming from a  
> traceroute and a given eventtype, i.e. subnet mask 32 )
> 	• Is there a chance, that information for a given IP and given  
> eventtype (e.g. utilization) is provided by more than one (MA)  
> service ?

Once the rest of my infrastructure is ready I should always have 2  
geographically distributed
MA's with very similar utilization data for any ESnet interface.  This  
is a critical part of
the architecture as far as I am concerned.  During network outages or  
server maintenance,
it is quite possible that one of the systems will have holes in the  
data.

We have also contemplated having 3 MA's.  2 of which are based on  
independent systems that
are doing active polling and have the current data for the last week  
(or month), and a 3rd,
which will have archived historical data which is synthesized from the  
2 servers, with any
data holes filled in.


> 	• If yes, how do we visualize that and assure the information is  
> consistent?

People working on operational purposes will want one display with the  
'best' data.

People working on network research, or measurement maintenance will  
want to see all
the data, and be especially interested in when various sources are  
different.

So, I think the default could be to pick one.  But eventually we will  
want the ability
to select and compare the data from multiple servers.


>         • If not, what is the reason of looking into multiple options?
> Discussion on other use cases are of course welcome :)
>
> Best regards,
> Nina