A method of transmitting data streams via satellite, comprising: receiving, by a digital transport formatter, a plurality of original, MPEG-compliant, data streams (TS1, TS2, TS3), each original data stream having its own timing information; combining, by the digital transport formatter, the plurality of original data streams into a single combined data stream which is also MPEG compliant, the combining comprising: for each one of the original data streams, re-encapsulating packets from the original data stream including packet headers into an output stream of newly-generated packets (315, 320, 325), such that an original packet of the original data stream is split among two or more newly generated packets, and wherein a single new packet identifier, PID, is assigned to the newly-generated packets of the output stream, the new packet identifier being unique to the output stream; and combining the output streams of newly generated packets to form the single combined data stream; preparing, at a satellite modulator, the single combined data stream for uplink and uplinking it to a satellite; the method further comprising, at a receiver site: receiving a downlink transmission from the satellite, the downlink transmission including the single combined data stream; de-combining the single combined data stream into the plurality of original data streams; and passing respective original data streams to one or more target destinations (136, 140). receiving, by a digital transport formatter, a plurality of original, MPEG-compliant, data streams (TS1, TS2, TS3), each original data stream having its own timing information; combining, by the digital transport formatter, the plurality of original data streams into a single combined data stream which is also MPEG compliant, the combining comprising: for each one of the original data streams, re-encapsulating packets from the original data stream including packet headers into an output stream of newly-generated packets (315, 320, 325), such that an original packet of the original data stream is split among two or more newly generated packets, and wherein a single new packet identifier, PID, is assigned to the newly-generated packets of the output stream, the new packet identifier being unique to the output stream; and combining the output streams of newly generated packets to form the single combined data stream; preparing, at a satellite modulator, the single combined data stream for uplink and uplinking it to a satellite; for each one of the original data streams, re-encapsulating packets from the original data stream including packet headers into an output stream of newly-generated packets (315, 320, 325), such that an original packet of the original data stream is split among two or more newly generated packets, and wherein a single new packet identifier, PID, is assigned to the newly-generated packets of the output stream, the new packet identifier being unique to the output stream; and combining the output streams of newly generated packets to form the single combined data stream; the method further comprising, at a receiver site: receiving a downlink transmission from the satellite, the downlink transmission including the single combined data stream; de-combining the single combined data stream into the plurality of original data streams; and passing respective original data streams to one or more target destinations (136, 140). receiving a downlink transmission from the satellite, the downlink transmission including the single combined data stream; de-combining the single combined data stream into the plurality of original data streams; and passing respective original data streams to one or more target destinations (136, 140).