Define the specifications required for intermodal and/or cross vertical interactions

[swaldron58]

The team has stated the need to define the API behavior needs for interoperability between travel verticals such as hotel, air, car, rail, cruise, tours and so on. A hotel booking, for example, is a hotel booking no matter if requested by a traveler or an airline. An air booking is a an air booking if requested by a traveler or a rail operator to make a connection. Or are they?
I will open a separate issue on intermodal and cross vertical transactions focused on security. The team quickly identified several issues there.
This issue is to explore the non security issues. The major issue I can see is a booking such as tour, hotel, rail, air implies all four parts have an implied relationship. There is a tour I want to take, I need to hotel close by, and I will use rail connecting to air to get there. That's still leaving out ground transportation or car rental. A traveler making all the bookings is on hook to deal with any changes. The service providers would be expected to sort out what happens when one service changes (ex: tour is canceled that day) and the rest must react. One could assume a client side app would be expected to do it all or is there a need at the API level to allow one service provider to communicate to another a change is needed? Given the growing requirements for trip level bundling this could be a hot topic.