Node Provisioning Protocol Interface Procedures#

The Node Provisioning Protocol Interface is used when a Node Provisioning Protocol Interface procedure is executed.

The Node Provisioning Protocol Interface (NPPI) is an interface used by the node to route the Provisioning PDUs between the Provisioner and the layer that is executing the provisioning protocol.

Device Key Candidate#

The Device Key Candidate is a key that can replace the device key when activated. The Device Key Candidate may be delivered to the node by using an OOB mechanism or may be generated by successfully executing the Device Key Refresh procedure. When the Device Key Candidate is available, it can be activated, and replaces the device key.

Device Key Refresh Procedure#

The Device Key Refresh procedure is used to change the device key (DevKey) without reprovisioning a node and without the need to reconfigure the node.

The Device Key Refresh procedure does not transfer a device key to the device over-the-air. Instead, it uses the provisioning protocol to compute the Device Key Candidate. The device key value change that results from this procedure is thus performed at the same security level as is provisioning of the unprovisioned device. The Address, NetKey, NetKey Index, and IV Index that are provided using the provisioning protocol must match the values stored on the node. The value of the Flags field is ignored.

Node Address Refresh Procedure#

The Node Address Refresh procedure is used to change the node’s device key and unicast address without reprovisioning.

Executing this procedure ends the current term of the node and starts a new term.

The NetKeys and AppKeys stored in the node are not removed during the procedure. Other configuration states may change. For example, the Composition Data state may change upon successful procedure completion if features are added or removed.

Node Composition Refresh Procedure#

The Node Composition Refresh procedure is used to change the device key of the node and to add or delete models or features of the node without reprovisioning.

Executing this procedure ends the current term of the node and starts a new term.

Almost all states of the node remain the same during this procedure. The Composition Data state of the node is changed.

For more details, refer to the Bluetooth Mesh Profile specification (1.1 draft) Chapter 3.11.8 Node Provisioning Protocol Interface procedures.