Patent ID: 8817758
Filing Date: 2014-08-26
Classification: H04W

Abstract:
1. A telecommunications system comprising: a first radio access technology having a first radio access network divided into a plurality of first areas, the first radio access network having a network core; a second radio access technology comprising a second radio access network divided into a plurality of second areas; a mobile terminal concurrently positioned in one of the first areas and one of the second areas, the first and second areas in which the mobile terminal is positioned being deemed to be equivalent routing areas allocated to the mobile terminal, the mobile terminal being registerable with each of the radio access technologies corresponding to the equivalent routing areas, the mobile terminal having an active state in which a communication session with the registered radio access technology is established and an inactive state when no such communication with the registered radio access technology is established, the mobile terminal being registerable with only one of the radio access technologies at a time; a home subscriber server entity common to both the first and second radio access technologies and which monitors/stores in which of the first and second areas the mobile terminal is registered; and a common control plane gateway entity positioned within the network core of the first radio access network, the common control plane gateway entity being configured such that communications from the first and second radio access networks, which relate to the first and second areas in which the mobile terminal is positioned, are routed through the common control plane gateway entity, wherein with no signaling to the home subscriber server entity, the mobile terminal is moveable from an inactive state corresponding to registration of the mobile terminal with the first radio access technology to an inactive state corresponding to registration of the mobile terminal with the second radio access technology.