The present document has been produced as an aspect of work to realise the stage 3 protocols to implement the stage 2 functionality for Interworking between Mission Critical systems and Land Mobile Radio systems as described in TS 23.283. Early stage 3 study work is documented in TR 24.883 which covers both MCPTT and MCData interworking. The document structure describes functionality modelled on TS 24.282 because the behaviour of an Interworking Function (IWF) for LMR MCData interworking is modelled on that of an MCData server, and the clause numbering is also based on that used in on TS 24.282 in order to aid comparison between the two specifications and identification of any behavioural changes. The reference numbering is based on that used in TR 24.883 and so may not be sequential.

The present document specifies the protocols needed to support a Mission Critical Data (MCData) system interworking with a Land Mobile Radio (LMR) system based on the IWF-2 interface between an MCData server and an Interworking Function (IWF) as described in TS 23.283.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

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