Object and Group IDs

[mengelbart]

Until now, we just ignored the existence of object and group IDs and deferred to the application. It would be nice if the transport implementation could handle reordering on the receiver side. I don't yet know how to handle this on the sender side. We could assign IDs automatically, but we don't know anything about the content, so we can't decide where new groups start. It may also be better to leave it to the application because it knows what the IDs mean in context. Maybe the transport can make sure it doesn't send nonsensical IDs?