20041030:IDV level II server

Hi Matt-

Matthew Huber wrote:
> hmmm, that sounds like a powerful and clean, but slow to implement  
> solution. I am plainly ignorant of how the server side works, so  
> forgive my questions.  But it seems that the Level III interface could  
> be leveraged. Simply go through the hoops for the in the GUI for the  
> Level III data, and then have another box that says "would you like  
> this as Level II data?"  then it's just a matter of a server-side  
> resolve to a different file name, which IDV more or less knows who to  
> read immediately.

You have to have something that knows how to read the Level II
data on the remote server.  Right now, neither OPeNDAP nor
ADDE have readers for Level II data.  In the Level III selector,
the server is queried for a list of available stations and for
a particualr station, the available times.  OPeNDAP
does not provide a mechanism so there needs to be some middleware
or a server enhancement to get the list of stations and
available times.  That's where THREDDS comes in.

> If it resolves to a non-existent file it exits cleanly....   am I  
> dreaming? :)

It doesn't hurt to dream for eventually those dreams may
become reality.  Right now, though, there is no protocol
that provides the information or data for remote access to
Level II data.

I've cc'd the others at Unidata who might be working on
these protocols.

> On Oct 29, 2004, at 3:58 PM, Don Murray wrote:
>
> > Matt-
> >
> > There is some work being done on a DODS/OPeNDAP server for
> > the Level II data but it is a work in progress.  The work is
> > being done by the University of Alabama-Huntsville, with
> > some help from the Unidata Program Center.  That will probably
> > be the method the IDV uses to access remote Level II data.
> > We will be relying on the THREDDS project will provide the middleware
> > that allows us to create a nice user interface to display
> > the available stations, etc like we have for the Level III
> > and other ADDE served data.  There are no plans that I know
> > of for a Level II ADDE server.
> >
> > Don Murray
> >
> >
> > Matthew Huber wrote:
> >
> > > HI jeff,
> > >     that sounds good.  I'm familiar with DODS/OpENDAP, although not   
> > > with  ADDE.  Since I"m familiar with the former my tendency would be  
> > > to move  forward with that and not with ADDE, but perhaps an expert  
> > > on both  protocols might prefer a different approach, so feel free 
> > > to  offer  opinions :).
> > > In terms of facilitation, advice is always welcome, what I do know,  
> > > is  that I don't know how much I don't know.  Certainly, there are  
> > > two  classes of problems, the first is simply setting up a system  
> > > that works  at all. Presumably DODS will work for that without much  
> > > hassle.   Second, is setting up a system that could work for a large  
> > > user base.   That's tougher.  That might also require more resources  
> > > on my end in  order to make that happen, so a grant might be in  
> > > order.  So I'd like  to try rolling it out in a small way, see what  
> > > the drain is  resource-wise and then think about how to roll this 
> > > out  globally.
> > > -m
> > > On Oct 29, 2004, at 11:57 AM, Jeff Weber wrote:
> > >
> > > > Hi Matt,
> > > >
> > > > I have cc'd the IDV head developer, Don Murray, on this as well in   
> > > > case he
> > > > can add/clarify/correct any information.
> > > >
> > > > The "nifty" interface utilizes ADDE servers to offer up this data.
> > > >
> > > > ADDE is part of the McIDAS package and delivers projection and   
> > > > navigation
> > > > information re the dataset. The IDV can also access DODS/OpENDAP   
> > > > servers.
> > > >
> > > > I think it would be great to offer the live stream via one of these
> > > > protocols for IDV use!
> > > >
> > > > Please let us know how we can help facilitate this.
> > > >
> > > > Cheers,
> > > >
> > > > Jeff
> > > > ---------------------------------------------------------------------
> > > > Jeff Weber                                    address@hidden         :
> > > > Unidata Program Center                        PH:303-497-8676         :
> > > > University Corp for Atmospheric Research      3300 Mitchell Ln        :
> > > > http://www.unidata.ucar.edu/staff/jweber      Boulder,Co 80307-3000   :
> > > > ---------------------------------------------------------------------
> > > >
> > > > On Fri, 29 Oct 2004, Unidata Support wrote:
> > > >
> > > > > ------- Forwarded Message
> > > > >
> > > > > > To: address@hidden
> > > > > > From: Matthew Huber <address@hidden>
> > > > > > Subject: serving level II data
> > > > > > Organization: UCAR/Unidata
> > > > > > Keywords: 200410290202.i9T22OvV006303
> > > > >
> > > > >
> > > > >
> > > > > Hi folks,
> > > > >     I'm going to ask a question from the opposite end :)  I'd like  to
> > > > > serve Level II data to IDV users, using that nifty interface, i.e.
> > > > > browse to a server and see what they have.... What protocol are  those
> > > > > data servers serving the data out over, and what software are they
> > > > > running to do this?  I'm looking for a more open approach than LDM  (I
> > > > > mean open in the sense of not having to have a strict peer-to-peer
> > > > > streaming arrangement).  Depending on the potential number of  
> > > > > clients  I
> > > > > could potentially serve the national stream in real time...
> > > > >
> > > > > -Matthew Huber
> > > > > Purdue University


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Don Murray                               UCAR Unidata Program
address@hidden                        P.O. Box 3000
(303) 497-8628                              Boulder, CO 80307
http://www.unidata.ucar.edu/staff/donm
"There's someone in my head, but it's not me"    Roger Waters
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