Abstract: A method includes: receiving, in a first tag, a first security certificate for a second tag and a session token corresponding to an arrangement involving the first and second tags; determining, by the first tag, that the second tag satisfies a proximity criterion with regard to the first tag; receiving, in the first tag and from the second tag, the first security certificate and the session token; and generating, by the first tag and in response to the determination and the receipt of the first security certificate and the session token, a first output corresponding to verification of a custodian of the second tag as a participant in the arrangement.

Abstract: A method includes: receiving, by a first tag and from a second tag, a first message including an identifier of the second tag, the first and second tags configured for coupling to respective first and second physical objects to organize activities; identifying, by the first tag and based on a proximity measure, the second tag for a pairing process to register the second tag as a child tag of the first tag; and providing, by the first tag, a second message with the identifier to a processing device configured to register the second tag as the child tag of the first tag.