B.0 Introduction

This clause describes the behaviour of CoAP layer for multicast group fan out procedure. Figure B.0-1 illustrates the steps involved in the interaction.

Figure B.0-1: Multicast group fan out procedure

• The Group Hosting CSE (CoAP client) shall use the Non-confirmable Method for the resource to the Member Hosting CSEs (CoAP server). The Group Hosting CSE shall provide a unique Token value in the request.
• The Member Hosting CSE, upon successful processing of the request, shall send an appropriate response in a separate Non-confirmable message with the same Token value.