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>From: "Arthur A. Person" <address@hidden> >Organization: PSU >Keywords: 200503102200.j2AM0Lq2027557 IDD Hi Art, re: downstream IDD users of atm.geo.nsf.gov >Can you tell me who the typical subscribers are? Are these primarily >edu/gov type sites, or are there commercial sites as well? The users are .edu, .gov, international users (.ar, .au, .bb, .br, .ca, .cl, .cr, .hk, .mx, .pt, .ru, .vn) and, before the commodity Internet connection to atm was closed to IDD traffic, .org (the Museum of Science in Boston). >How many sites >are requesting lower bandwidth streams like WMO or MCIDAS Most are getting the lower bandwidth feeds. >and how many >sites request the higher bandwidth feeds such as CONDUIT or NEXRAD2? Some are getting these. The mixture is fluid. You can always see who is getting data from atm through the real time statistics pages: http://my.unidata.ucar.edu/content/software/idd/rtstats/topoindex.php?tree Click on a particular feed type and then search for atm.geo.nsf.gov and see who it is feeding. >Also, is all this traffic on Internet 2, or does some of it go out on >commodity networks? It used to be a mixture, but that changed when it was demonstrated that the IDD would consume NSF's entire commodity Internet connection bandwidth when their I2 connection failed. >If so, how much would be going out on commodity >networks? A small fraction. It is my impression that no site using commodity Internet ever requested large volumes of data. They typically were interested in IDS|DDPLUS, UNIWISC (aka MCIDAS), NNEXRAD (some, not all), FNEXRAD, DIFAX, etc. >Internet 2 is no problem for us to service, but I think there >could be costing or bandwidth issues if there's much commodity internet >required. The current state of affairs is that no site using commodity Internet is allowed to request data from atm. Those sites that have to use commodity Internet have been shifted off to other relay sites like idd.unidata.ucar.edu. Cheers, Tom -- NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.