I haven't used the SIRI functionality in OBA myself, but here's what I understand. Also, keep in mind that OBA is a suite of software with some standalone projects.
>(1) I would like to convert a GTFS-Realtime feed into a CEN SIRI VM service and offer this service as a producer to arbitrary consumer.
I think this is supported in the onebusaway-application-modules, as MTA Bus Time (built on OBA) offers a SIRI VM and SM REST API:
...but folks from MTA would probably be in the best place to answer if an input GTFS Realtime feed can be output to this SIRI API.
(1) I would like to convert a GTFS-Realtime feed into a CEN SIRI VM service and offer this service as a producer to arbitrary consumer.
This should also be supported in the onebusaway-application-modules:
I don't know of anyone using SIRI SX as input, but there might be folks out there that I don't know of.
If anyone knows better please jump in to correct me.
Center for Urban Transportation Research
University of South Florida