perfsonar development work

["Michael Bischoff" <>]

URN's (https://wiki.internet2.edu/confluence/display/PSPS/URNs) should solve 
most problems
even with local ip ranges as a domain is always included.

We discussed about things that would solve this. To me it really sounds like 
a mismatch
between what the LS is suppose to do and what the topology service is suppose 
to do,
undoubtly in the topo service this problem is trivial to solve as they have 
all the
information right there and in the LS infrastructure it would feel like 
hack-ar-y thing.
Since that discussion ended in strong disagreement and arguments I'll not 
rattle it up again.

The idea with LS client api was to represent the topology elements as URN's 
(but I beleave it
is a bit 'lax' at the moment.) I think you can either query with just the 
ip's without the
domain information and I would probably then return anything that I can find 
with that ip but
in the data I return I try to also supply domain and the client(software that 
calls the api)
can sort it out that or simply supply a domain with the ip and the problems 
would go away
too.

The only issues that are really there is whether I can extract enough 
information from the
back-end / infrastructure.

Suggestions with regard to issues with visualising would bring us back in the 
old discussion.

The problem isn't new; to globally uniquely identify a node a ip + subnet 
doesn't cut it from
the URN proposal I take it addign domain information fixes this issue.

As far as the LS api goes I think that the policy of leaving filtering data 
is up to the
programmer and not the api saves from headaches in the future.

regards

Michael B.

> 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
>>
>
>