This document describes in more detail the relation between the interworking functionality and the TETRA SwMI from the perspective of operators and users. The focus is on the usage during transition and what  the expected features needed from this perspective are. It sets aside the needed basic functionality for interworking like voice calls, data messages and designates priorities in a clear overview of 1) must-have, 2) nice to have and 3) not prioritized in this service overview for the standardized IWF features. The added use cases in chapter 5 are reflections from operators and considers how the IWF can be managed during operation.

It all started with a discussion at the TCCA ISI WG#100 in Helsinki that developed into a focus forum stream during the Critical Communications World 2021 in Madrid: the identification of features, functions, and services that could result in a new system connection mapping the generation from LMR to 3GPP Mission Critical Services. Last week the final editorial check on the grammar and style has been done and the publication of the TETRA Interworking Service Overview is a fact.

According to Michel Duits (Senior Principal Engineer / Product manager ISI at DSB), who actively participated n the process,  it was not an easy road from the focus forums, via the online workshops during Covid19, towards the interesting discussions on perspective, deployments, use cases at the end.

In his short article on LinkedIn, Duits expressed his gratitude to all who joined the last two years the workshops, focus forums, discussions, resolution meetings and for reading and improving the document. At the same time, work on making the IWF a reality is ongoing as demonstrated during the last two ETSI Plugtests.

Early next year the Task Force will organize a workshop to sum up the highlights and will investigate how the interworking options could develop into more and future implementations.

The invitation for this workhop will be distributed via the email list TETRA-IWF@tcca.info.

If you are interested, the Service Overview can be downloaded here.