It is probably better that upon connecting, a Participant adapter (the Connection of an Agent Device or V/PM device) register itself with the Identity through which the Connection is expressed. This means that the Agent Device serving the device represented by the Participant adapter does not have to acquire the Axle's identifier in order to add a given Participant adapter to the Agent Device's set of served Participant adapters expressed in a given Axle. Perhaps this will permit the Agent Device instances to express these served Participant adapters in an Identity even when an Agent Device does not know the Identity's Axle.
It is hoped this will permit an individual to connect a device to an Agent Device operated by another individual without the first individual having to disclose their Axle to the second. I like this; it is a more flexible proposition.