I am planning to implement Peer to Peer data exchange between 2 iOS devices. I have the following queries. My devices are connected through Ethernet. I would prefer to use this route if possible before switching over to Wifi. I can see there is an option to use prohibitedInterfaceTypes but that doesn't guarantee the route to use Ethernet when there are multiple available. Does the connection automatically switch between ethernet and Wifi or does that have to be handled via isViable and betterPathAvailable? I'm unsure when I should be using a custom framing protocol. I just need to exchange codable objects between the devices. Is the custom protocol required only if I use TCP as the underlying protocol? Can NSURLSessionStreamTask be used for this use case?

I have a use case where I have two iOS devices that needs to exchange JSON objects between each other. It is a bidirectional flow of data and the request can trigger from each device at any point of time. I would like to understand if I can achieve this using CoreBluetooth? I have checked multipeer connectivity and although that does do the Job for me, it seems an overkill since I don't have multiple peers. I have a set of devices that will always be talking to one other device i.e, 1:1 mapping of all the devices that I have and there is no cross connection.