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Jon, > My name is Jon Hurst, I work with James Pelagatti at MIT/Lincoln > Laboratory. We are currently altering our LDM setup so we can serve > some internal data to outside organizations and we had some questions > about how to choose a feedtype. I realize that we could technically > choose any feedtype, and for testing we have been using EXP and also > FSL2, but in the long term perspective we were thinking it might be > worth establishing our own feedtype for the Lab. If we do not create > our own feedtype, I suppose we'll have to piggyback off of some other > feed, or perhaps use the default ANY or EXP feedtypes. Here are my > questions in a semi-concise form: > > - How frequently are new feedtypes added and when does a distribution > site qualify for its own feedtype? Might we qualify? The LDM feedtype is represented as a 32-bit, unsigned integer with each bit corresponding to a primitive feedtype. As a consequence, only 32 primitive feedtypes are possible. Increasing the number of feedtypes would entail a change to the protocol and more than a little bit of programming. > - How much work would be involved with adding a new feedtype? It looks > like we would need to modify atofeedt.c, ldm.h and feedtypes.xml. I > guess the problem is ensuring that clients connecting to our server have > a version of ldm that recognizes our new feedtype. Is it common > practice to use the ANY or EXP feedtype in the short term with the goal > of switching to a unique feedtype upon the arrival of the next LDM version? I suggest using the EXP feedtype and choosing your product-identifiers very carefully so that they uniquely identify the data-products and are easily selected via regular expressions. We, typically, recommend that the first component of such a product-identifier be an institutional or project name. > Any feedback would be very helpful. Thank you for your time. LDM has > been a great help! I'm glad to hear that. I'm currently working on an LDM replacement that won't have a problem with a limited number of feedtypes. Unfortunately, it won't be out until next year. Regards, Steve Emmerson Ticket Details =================== Ticket ID: RQS-322086 Department: Support LDM Priority: Normal Status: Closed