Data synchronization unit for a headend

Claim 3

The method of claim 1 , wherein step (b) comprises the step of inserting revised timing information in the first timing packet.

Claim 4

The method of claim 2 , further comprising the step of extracting timing information from the network data source.

Claim 5

The method of claim 1 , wherein the first timing packet is generated by a Media Access Control function and the first timing packet is a timing information element.

Claim 6

The method of claim 1 , wherein the headend is a Hybrid Fiber/Coaxial cable network headend.

Claim 7

The method of claim 1 , wherein the headend transmits the combined data stream using a Moving Picture Experts Group-2 transport stream.

Claim 8

The method of claim 1 , wherein the headend transmits the combined data stream using an Asynchronous Transport Mode transport stream.

Claim 9

A data synchronization unit adapted to provide Time Division Multiple Access (TDMA) synchronization for a headend that includes a network data source having a clock, and transmits a plurality of data streams on a transmission medium, wherein the plurality of data streams are multiplexed by a multiplexer into a combined data stream and include a first timing packet generated by the network data source, said data synchronization unit comprising: a timing packet replacer having a first input coupled to said clock of the network data source, a second input coupled to an output of the multiplexer, and an output coupled to the transmission medium; wherein said timing packet replacer extracts the first timing packet from the combined data stream, generates a second timing packet that compensates for a time delay of the multiplexer using said clock of the network data source, and inserts the second timing packet into the combined data stream in place of the first timing packet at the output of the multiplexer and before the combined data stream is transmitted by the headend.

Claim 10

A data synchronization unit adapted to provide Time Division Multiple Access (TDMA) synchronization for a headend that includes a network data source having a clock, and transmits a plurality of data streams on a transmission medium, wherein the plurality of data streams are multiplexed by a multiplexer into a combined data stream and include a first timing packet generated by the network data source, said data synchronization unit comprising: a timing packet replacer having a first input coupled to said clock of the network data source, a second input coupled to an output of the multiplexer, and an output coupled to the transmission medium; wherein said timing packet replacer extracts the first timing packet from the combined data stream, generates a second timing packet that compensates for a time delay of the multiplexer using said clock of the network data source, and inserts the second timing packet into the combined data stream in place of the first timing packet at the output of the multiplexer and before the combined data stream is transmitted by the headend.

Claim 11

The data synchronization unit of claim 8 , wherein the plurality of data streams comprise a video stream and an Internet data stream.

Claim 12

The data synchronization unit of claim 8 , wherein the first timing packet is generated by a Media Access Control function and the first timing packet is a timing information element.

Claim 13

The data synchronization unit of claim 8 , wherein the headend is a Hybrid Fiber/Coaxial cable network headend.

Claim 14

The data synchronization unit of claim 8 , wherein the headend transmits the combined data stream using a Moving Picture Experts Group-2 transport stream.

Claim 15

The data synchronization unit of claim 8 , wherein the headend transmits the combined data stream using an Asynchronous Transport Mode transport stream.

Claim 16

A headend adapted to transmit a plurality of data streams on a transmission medium comprising: a network data source that generates at least one of the plurality of data streams, and comprises a clock, wherein said at least one data streams include a first timing packet; a multiplexer coupled to said network data source that multiplexes the plurality of data streams into a combined data stream; and a data synchronization unit coupled to said multiplexer and said network data source, wherein said data synchronization unit provides Time Division Multiple Access (TDMA) synchronization for said headend, said data synchronization unit comprising: a timing packet replacer having a first input coupled to said clock, a second input coupled to an output of the multiplexer, and an output coupled to the transmission medium; wherein said timing packet replacer extracts the first timing packet from the combined data stream, generates a second timing packet that compensates for a time delay of the multiplexer using said clock of the network data source, and inserts the second timing packet into the combined data stream in place of the first timing packet at the output of the multiplexer and before the combined data stream is transmitted by the headend.

Claim 17

A headend adapted to transmit a plurality of data streams on a transmission medium comprising: a network data source that generates at least one of the plurality of data streams, and comprises a clock, wherein said at least one data streams include a first timing packet; a multiplexer coupled to said network data source that multiplexes the plurality of data streams into a combined data stream; and a data synchronization unit coupled to said multiplexer and said network data source, wherein said data synchronization unit provides Time Division Multiple Access (TDMA) synchronization for said headend, said data synchronization unit comprising: a timing packet replacer having a first input coupled to said clock, a second input coupled to an output of the multiplexer, and an output coupled to the transmission medium; wherein said timing packet replacer extracts the first timing packet from the combined data stream, generates a second timing packet that compensates for a time delay of the multiplexer using said clock of the network data source, and inserts the second timing packet into the combined data stream in place of the first timing packet at the output of the multiplexer and before the combined data stream is transmitted by the headend.

Claim 18

The headend of claim 14 , wherein the plurality of data streams comprise a video stream, an audio stream, and a network data stream.

Claim 19

The headend of claim 14 , wherein the first timing packet is generated by a Media Access Control function and the first timing packet is a timing information element.

Claim 20

The headend of claim 14 , wherein the headend is a Hybrid Fiber/Coaxial cable network headend.