BT's 21CN trials will include Siemens' SURPASS hiG 1200 Trunk Gateway, a carrier grade VoIP trunk media gateway, which provides mediation between the core IP infrastructure of a next generation network and the existing circuit-switched network. Siemens will also supply Juniper Networks' T640 core router platform for the IP/MPLS backbone. http://www.siemens.comhttp://www.juniper.net