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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 hecan 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 MessageTo: address@hidden From: Matthew Huber <address@hidden> Subject: serving level II data Organization: UCAR/Unidata Keywords: 200410290202.i9T22OvV006303Hi 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-peerstreaming arrangement). Depending on the potential number of clients Icould potentially serve the national stream in real time... -Matthew Huber Purdue University
-- ************************************************************* 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 *************************************************************