Abstract: System, methods, nodes, and instruction set for routing a session invitation from a first network (101) to a second network (112) are described. The first network (101) and the second network (112) are interconnected via at least two points of interconnect (114, 120). A first control node (124) receives a session invitation to a first user equipment (106), both are part of the first network (101). The first control node (124) determines whether a breakout condition for routing of the session invitation to the second network (112) is fulfilled. If so, a second control node (128) of the first network (101) selects a point of interconnect (114, 120) to the second network (112), considering a capability information characterizing the first control node (124). Therefore the session invitation may be routed in an efficient way from the first network (101) to the second network (112).

Abstract: There is provided a method of operating an IP Multimedia Subsystem Access Gateway (IMS-AGW) in order to support the transmission of media to and from an endpoint, using an IMS, wherein the endpoint implements an alternative media transport protocol other than Real-time Transport Protocol (RTP). The method comprises the IMS-AGW receiving instructions from an IMS Application Level Gateway (IMS-ALG) for an alternative media transport protocol connection with the endpoint and a RTP connection within the IMS, the instructions including more than one RTP payload type number and a dynamic binding of each of the more than one RTP payload type number to a statically defined codec identifier. The IMS-AGW stores the dynamic binding. Then, when translating between alternative media transport protocol packets and RTP packets, the IMS-AGW uses the stored binding to map between an RTP payload type number and a codec identifier used by the alternative media transport protocol.

Abstract: System, methods, nodes, and instruction set for routing a session invitation from a first network (101) to a second network (112) are described. The first network (101) and the second network (112) are interconnected via at least two points of interconnect (1 14, 120). A first control node (124) receives a session invitation to a first user equipment (106), both are part of the first network (101). The first control node (124) determines whether a breakout condition for routing of the session invitation to the second network (112) is fulfilled. If so, a second control node (128) of the first network (101) selects a point of interconnect (114, 120) to the second network (112), considering a capability information characterizing the first control node (124). Therefore the session invitation may be routed in an efficient way from the first network (101) to the second network (112).

Abstract: There is provided a method of operating an IP Multimedia Subsystem Access Gateway (IMS-AGW) in order to support the transmission of media to and from an endpoint, using an IMS, wherein the endpoint implements an alternative media transport protocol other than Real-time Transport Protocol (RTP). The method comprises the IMS-AGW receiving instructions from an IMS Application Level Gateway (IMS-ALG) for an alternative media transport protocol connection with the endpoint and a RTP connection within the IMS, the instructions including more than one RTP payload type number and a dynamic binding of each of the more than one RTP payload type number to a statically defined codec identifier. The IMS-AGW stores the dynamic binding. Then, when translating between alternative media transport protocol packets and RTP packets, the IMS-AGW uses the stored binding to map between an RTP payload type number and a codec identifier used by the alternative media transport protocol.