ETSI TS 101 747 V1.1.1 (2001-07). Technical Specification. Terrestrial Trunked Radio (TETRA); Voice plus Data(V+D); IP Interworking (IPI)

The present document defines IP Interworking (IPI) between two TETRA networks for the transfer of IP data while MS
migrates from one SwMI to another.
The present document defines the use of GPRS Tunnelling Protocol (GTP), the Gateway GPRS Support Node (GGSN)
and ISI for IPI.
The present document proposes limited extension to SNDCP of the TETRA Air Interface and ISI in order to use the IP
interworking functionality of the GGSN and to use standardized Gn and Gp interfaces. As a consequence, the protocols
and signalling messages already defined and developed for GPRS can be used. The use of standard GGSN and other
GPRS Backbone elements and the existing interworking functions is described for IPI. The architecture ensures re-use
of the already standardized TETRA ISI MobilityManagement, HDB and VDB functions and TETRA registration
procedures between the Mobile Station and SwMI.Keywords: internet, interworking, IP, packet mode, security, TETRA