Processing transport packets

A relay node for processing transport packets comprising:

• a buffer configured to store the transport packets, the transport packets conveying:
• (i) data stream units forming a data stream, and (ii) correction data units relating to the data stream units, each transport packet containing the data stream units, the correction data units sufficient to enable generation of substitute data stream units for at least one transport packet, and information identifying the content of the units in that transport packet, the relay node further comprising:
• a receiver configured to receive transport packets, the data stream units in the transport packets received at the relay node being insufficient to reconstitute the data stream;
• a generator configured to use at least some of the correction data units and the data stream units in the received transport packets to generate substitute data stream units thereby to substantially recover the data stream at the relay node;
• a packetiser configured to packetise, at the relay node, the data stream units of the substantially recovered data stream with correction data units to form output transport packets for transmission from the relay node;
• and
• a transmitter configured to transmit said output transport packets from the relay node.

A computer program product embodied on a computer readable storage device comprising computer readable instructions for execution by computer processing means at a relay node comprising:

• processing transport packets, the transport packets conveying:
• (i) data stream units forming a data stream, and (ii) correction data units relating to the data stream units generated from an operation to combine correction data from at least two encrypted data stream units, each transport packet containing the data stream units, the correction data units, and information identifying the content of the units in that transport packet, the instructions further comprising instructions for:
• receiving transport packets at the relay node, the data stream units in the transport packets received at the relay node being insufficient to constitute the data stream;
• using at least some of the correction data units and the data stream units in the received transport packets to generate substitute data stream units thereby to substantially recover the data stream at the relay node;
• packetising, at the relay node, the data stream units of the substantially recovered data stream with correction data units to form output transport packets for transmission from the relay node;
• and
• transmitting said output transport packets from the relay node.

A method comprising:

• processing transport packets, each of the transport packets comprising encrypted data stream units and non-encrypted correction data units, the correction data units conveying information relating to encrypted data stream units sufficient to enable generation of substitute data stream units for at least one transport packet, and each transport packet containing unencrypted recovery data indicating how the correction data units relate to the encrypted data stream units, the method further comprising:
• receiving transport packets at a relay node;
• using at least some of the correction data units in the received transport packets and the unencrypted recovery data to recover a lost transport packet at the relay node;
• packetising, at the relay node, correction data units to form output transport packets for transmission from the relay node;
• and
• transmitting said output transport packets from the relay node.

A method comprising:

• processing transport packets, each of the transport packets comprising encrypted data stream units, non-encrypted correction data units generated from an operation performed on a first encrypted data stream unit and a second encrypted data stream unit, and a sequence number, the sequence number conveying information relating to encrypted data stream units forming a data stream, and each transport packet containing unencrypted recovery data indicating how the non-encrypted correction data units relate to the encrypted data stream units, the method further comprising:
• receiving transport packets at a relay node;
• using at least some of the units in the received transport packets and the unencrypted recovery data at the relay node to generate substitute units which relate to the encrypted data stream units for use in substantially recovering the data stream;
• packetising, at the relay node, at least some of the units of the received transport packets and the substitute units to form output transport packets for transmission from the relay node;
• and
• transmitting said output transport packets from the relay node.