A system comprising: one or more satellite gateway earth stations; a plurality of terminals, each of the plurality of terminals being arranged to receive communications via a satellite and a respective spot beam of a plurality of spot beams formed by the satellite, wherein: the one or more satellite gateway earth stations are arranged to receive one or more multicast streams from an external network, and when a satellite gateway earth station of the one or more satellite gateway earth stations is configured to be in a static forwarding mode, the satellite gateway earth station is statically configured to replicate and forward each of the one or more multicast streams over one or more first respective outroute carriers of at least one first respective spot beam of the plurality of spot beams regardless of whether any terminals are arranged to actively receive any of the one or more multicast streams, when the satellite gateway earth station is configured to be in a dynamic forwarding mode, the satellite gateway earth station is dynamically configured to replicate and forward one of the one or more multicast streams over one or more second respective outroute carriers of at least one second respective spot beam of the plurality of spot beams only when at least one respective terminal is arranged to actively receive each of the ones of the one or more multicast streams over the one or more second respective outroute carriers of the at least one second respective spot beam of the plurality of spot beams; and characterized in that: the satellite gateway earth station is further configured to receive, from a terminal via a satellite, the information informing the satellite gateway earth station to forward received traffic from the multicast stream to the terminal via an outroute of a spot beam of the satellite that communicates with the terminal, when the satellite gateway earth station is configured to be in the dynamic forwarding mode.. one or more satellite gateway earth stations; a plurality of terminals, each of the plurality of terminals being arranged to receive communications via a satellite and a respective spot beam of a plurality of spot beams formed by the satellite, wherein: the one or more satellite gateway earth stations are arranged to receive one or more multicast streams from an external network, and when a satellite gateway earth station of the one or more satellite gateway earth stations is configured to be in a static forwarding mode, the satellite gateway earth station is statically configured to replicate and forward each of the one or more multicast streams over one or more first respective outroute carriers of at least one first respective spot beam of the plurality of spot beams regardless of whether any terminals are arranged to actively receive any of the one or more multicast streams, when the satellite gateway earth station is configured to be in a dynamic forwarding mode, the satellite gateway earth station is dynamically configured to replicate and forward one of the one or more multicast streams over one or more second respective outroute carriers of at least one second respective spot beam of the plurality of spot beams only when at least one respective terminal is arranged to actively receive each of the ones of the one or more multicast streams over the one or more second respective outroute carriers of the at least one second respective spot beam of the plurality of spot beams; and characterized in that: the satellite gateway earth station is further configured to receive, from a terminal via a satellite, the information informing the satellite gateway earth station to forward received traffic from the multicast stream to the terminal via an outroute of a spot beam of the satellite that communicates with the terminal, when the satellite gateway earth station is configured to be in the dynamic forwarding mode.. the one or more satellite gateway earth stations are arranged to receive one or more multicast streams from an external network, and when a satellite gateway earth station of the one or more satellite gateway earth stations is configured to be in a static forwarding mode, the satellite gateway earth station is statically configured to replicate and forward each of the one or more multicast streams over one or more first respective outroute carriers of at least one first respective spot beam of the plurality of spot beams regardless of whether any terminals are arranged to actively receive any of the one or more multicast streams, when the satellite gateway earth station is configured to be in a dynamic forwarding mode, the satellite gateway earth station is dynamically configured to replicate and forward one of the one or more multicast streams over one or more second respective outroute carriers of at least one second respective spot beam of the plurality of spot beams only when at least one respective terminal is arranged to actively receive each of the ones of the one or more multicast streams over the one or more second respective outroute carriers of the at least one second respective spot beam of the plurality of spot beams; and characterized in that: the satellite gateway earth station is further configured to receive, from a terminal via a satellite, the information informing the satellite gateway earth station to forward received traffic from the multicast stream to the terminal via an outroute of a spot beam of the satellite that communicates with the terminal, when the satellite gateway earth station is configured to be in the dynamic forwarding mode..