Packet data service in a mobile communications system

A mobile communications network comprising:

• a plurality of mobile stations having a packet data capability,
• a switching and management infrastructure having a mobility management capability for the mobile stations which have a logical packet data connection of a first type activated between said infrastructure and the respective mobile station,
• a gateway packet node connected to said switching and management infrastructure by means of a standard interface initially defined to be used between packet nodes in a different type of a packet radio network in order to provide a packet mode connection to an external communications network,
• said switching and management infrastructure and the gateway packet node being arranged to activate a logical packet data connection of a second type and to tunnel data packets between the infrastructure and the gateway packet node according to protocols and signaling messages defined for said standard interface,
• and wherein said switching and management infrastructure further comprises a signaling interface to another switching and management infrastructure in a separate mobile communications network, and wherein said gateway packet node has a second standard interface to another gateway packet node in said separate mobile communications network, said second standard interface being initially defined to be used between gateway packet nodes in said different type of communications network.

A method of establishing packet mode communication from a mobile communications network to external communications networks, said mobile communications network comprising a plurality of mobile stations and a trunked radio switching and management infrastructure, said method comprising:

• activating a packet protocol context between a mobile station and the trunked radio switching and management infrastructure with a trunked radio infrastructure-specific network-layer protocol,
• using the mobility management of the trunked radio switching and management infrastructure for managing the mobility of the mobile station having the packet protocol context,
• interconnecting the trunked radio switching and management infrastructure to a gateway packet node by means of a standard interface initially defined to be used between packet nodes in another packet network,
• using protocols and signaling messages defined for said standard interface, for activating packet data protocol context between the trunked radio switching and management infrastructure and the gateway packet node.