The "name space" in Max is global - when you have objects that have names associated with them such as coll, send, receive, table, or buffer~ , you can share data between Max for Live devices. In these cases, the Max name space is shared, but the "signal processing space" is independent - each Max for Live device processes its audio or data separately.

If you want a named object to be unique to a device, use three dashes (---) to start the name of your buffer or send/receive destination.