An user equipment comprising: a transceiver arranged to communicate with a mobile communication network using a plurality of network connections, each network connection communicating via a different network slice type of the mobile communication network; and a processor arranged to: select a first of the network connections via a specific network slice type to establish a communication session with an IMS network to convey IMS signaling; receive a first request from an application running on the user equipment, the first request to establish an internet protocol multimedia subsystem, IMS, session with the IMS network, the IMS network reachable via the plurality of network connections, wherein the first request comprises a plurality of media types; select a second of the network connections via a specific network slice type to be used for communicating media traffic for each media type of the plurality of media types; and transmit, using the first of the network connections, an IMS session request message to the IMS network, wherein the IMS session request message indicates one or more parameters to be used for communicating the media traffic for each media type over the selected network connection for that media type. a transceiver arranged to communicate with a mobile communication network using a plurality of network connections, each network connection communicating via a different network slice type of the mobile communication network; and a processor arranged to: select a first of the network connections via a specific network slice type to establish a communication session with an IMS network to convey IMS signaling; receive a first request from an application running on the user equipment, the first request to establish an internet protocol multimedia subsystem, IMS, session with the IMS network, the IMS network reachable via the plurality of network connections, wherein the first request comprises a plurality of media types; select a second of the network connections via a specific network slice type to be used for communicating media traffic for each media type of the plurality of media types; and transmit, using the first of the network connections, an IMS session request message to the IMS network, wherein the IMS session request message indicates one or more parameters to be used for communicating the media traffic for each media type over the selected network connection for that media type. select a first of the network connections via a specific network slice type to establish a communication session with an IMS network to convey IMS signaling; receive a first request from an application running on the user equipment, the first request to establish an internet protocol multimedia subsystem, IMS, session with the IMS network, the IMS network reachable via the plurality of network connections, wherein the first request comprises a plurality of media types; select a second of the network connections via a specific network slice type to be used for communicating media traffic for each media type of the plurality of media types; and transmit, using the first of the network connections, an IMS session request message to the IMS network, wherein the IMS session request message indicates one or more parameters to be used for communicating the media traffic for each media type over the selected network connection for that media type.