an information provision transaction (HAN Only Message).
A Message instance shall be an instance of one of the Messages detailed in this GBCS.
The Device Specifications define the minimum functional capabilities required of Devices.
Except where those functional capabilities are internal to the Devices or are accessed via the Device’s User Interfaces, the minimum functional capabilities shall be invoked by, and / or result in, Messages being passed via the Devices’ Network Interfaces.
The GBCS is the technical specification, sufficient for the creation by the originator(s) and processing by the target(s), of each Message, where the Message is required in order to implement minimum functionality defined in the Device Specifications.
Specifically, the GBCS details the format, structure and associated processing for each of the Messages required to implement the Device Specifications’ minimum functionality.
There are two classifications of Message:
HAN Only Message4, where both the original sender and ultimate recipient are Devices within the same Smart Metering Home Area Network (SMHAN); and
Remote Party Message, where either the original sender or the ultimate recipient is not a Device.
A Remote Party Message shall only be of one of the following:
Where a Remote Party is known to a Device by way of that Remote Party’s Security Credentials being stored on the Device (as specified in Section 220.127.116.11), the Remote Party is referred to as a Known Remote Party (KRP). Otherwise, it is referred to as an Unknown Remote Party (URP).
Commands requiring a Response to an Unknown Remote Party shall always be sent to the Device by the Device’s Access Control Broker (see Section 18.104.22.168).
For clarity, Type 2 Devices shall not be required to support any Remote Party Messages. Thus, provisions in this GBCS in relation to Remote Party Messages shall not apply to Type 2 Devices.
Remote Parties and Devices are collectively referred to in this GBCS as Smart Metering Entities.