Statistical Multiplexing in Satellite Communication Networks

1. A satellite communication system, comprising: a hub; and at least one subnet, each said subnet configured as a private network, and each said subnet comprising at least one gateway and at least one terminal, wherein the at least one gateway in each subnet is configured to communicate with the at least one terminal in the same subnet and with the hub, and wherein the at least one terminal in each subnet is configured to communicate with the at least one gateway in the same subnet and with the hub; and wherein the hub is configured to share bandwidth between a first subnet in the satellite communication system and at least one of (a) one or more independent terminals in the satellite communication system, or (b) one or more additional subnets in the satellite communication system.

2. The satellite communication system of claim 1 , wherein a plurality of transmission channels are used by the at least one gateway or the at least one terminal of the at least one subnet, and wherein the plurality of transmission channels share a bandwidth pool.

3. The satellite communication system of claim 1 , wherein a first transmission channel used by the at least one gateway or the at least one terminal of the first subnet is allocated on a dedicated bandwidth pool.

4. The satellite communication system of claim 1 , wherein a first gateway in the first subnet comprises: a LAN interface configured to connect the first gateway to at least one user application; and at least one controller configured to: process and transmit data received from at least one user application to the at least one remote terminal in the first subnet or to the hub; and process and transmit data received from the hub or from the at least one remote terminal in the first subnet to at least one user application.

5. The satellite communication system of claim 4 , wherein the first gateway in the first subnet further comprises: a reception chain; a radio frequency (RF) splitter coupled to the reception chain; at least one receiver coupled to the RF splitter and coupled to the at least one controller in the first gateway, wherein the at least one receiver is configured to: receive a burst containing data, transmitted by a first terminal in the first subnet; decode the received burst and receive the data; and transmit the received data, over a first local area network (LAN), to the at least one controller in the first gateway.

6. The satellite communication system of claim 5 , wherein the at least one receiver is further configured to: tune on a first transmission channel and receive a first burst transmitted from a first terminal in the first subnet; and tune on a second transmission channel and receive a second burst transmitted from a second terminal in the first subnet, wherein the second burst differs from the first burst in one or more of frequency, symbol rate, modulation, or coding, wherein an interval between an end of the first burst and a beginning of the second burst does not exceed an interval of a guard between two regular transmission timeslots.

7. The satellite communication system of claim 1 , wherein each subnet is configured as a private network so that exchange of data between entities in different subnets is blocked.

8. The satellite communication system of claim 7 , wherein each subnet is configured as a private network by assigning one or more unique virtual LAN identifiers to said subnet.

9. The satellite communication system of claim 7 , wherein each subnet is configured as a private network using virtual routing.

10. The satellite communication system of claim 1 , wherein a first terminal in the first subnet is configured to: receive data transmitted by a second terminal in the first subnet, without said data being routed either via the hub or via a gateway in the first subnet.

11. The satellite communications system of claim 5 , wherein: the first subnet includes a plurality of remote terminals; the first gateway in the first subnet comprises multiple receivers coupled to the RF splitter and coupled to the at least one controller in the first gateway; and the first gateway is configured to simultaneously receive a plurality of bursts simultaneously transmitted by the plurality of remote terminals in the first subnet using the multiple receivers.

12. The satellite communications system of claim 5 , wherein the first gateway in the first subnet further comprises a transmission chain and at least a first controller and a second controller, and wherein: the second controller is coupled to the at least one receiver; the first controller and the second controller are coupled to the transmission chain via an RF switch; and the first gateway is configured to have only one controller active at any given time.

13. A method, comprising: receiving, by a hub in a satellite communication system, one or more bandwidth requests from at least one of (a) one or more gateways in one or more subnets of the satellite communication system, (b) one or more terminals in the one or more subnets of the satellite communication system, or (c) one or more independent terminals in the satellite communication system; processing, by the hub in a satellite communication system, the received bandwidth requests, and determining an amount of bandwidth to allocate for each received bandwidth request using at least one quality-of-service algorithm; and allocating, by the hub in a satellite communication system, bandwidth in accordance with a time-frequency plan to the requesting one or more gateways, one or more terminals, or one or more independent terminals.

14. The method of claim 13 , wherein the at least one quality-of-service algorithm regards the one or more independent terminals as constituting at least one virtual subnet.

15. The method of claim 13 , wherein determining the amount of bandwidth to allocate for each received bandwidth request is based on one or more of: an amount of bandwidth requested; an amount of bandwidth available for distribution; and one or more service level agreements of the one or more subnets, the one or more gateways in the subnets, or the one or more terminals in the subnets.

16. The method of claim 13 , wherein determining a first amount of bandwidth to allocate for a first received bandwidth request is based on a first service level agreement including one or more of a priority characteristic, a committed information rate characteristic, or a maximal information rate characteristic.

17. The method of claim 13 , wherein processing the received bandwidth requests comprises: processing all bandwidth requests received by the hub by a single instance of said at least one quality-of-service algorithm.

18. The method of claim 13 , wherein processing the received bandwidth requests comprises: processing all bandwidth requests received by the hub using at least two instances of said at least one quality-of-service algorithm, wherein a first instance is used for processing bandwidth requests for transmitting traffic towards the hub, and one or more other instances are used for processing requests for transmitting traffic between gateways and terminals included in said one or more subnets.

19. The method of claim 13 , wherein processing the received bandwidth requests comprises: aggregating said bandwidth requests for each of the one or more subnets; determining an aggregated demand for each of the one or more subnets; determining a subnet service level agreement; determining total available bandwidth; and distributing the total available bandwidth to the one or more subnets in accordance with one or more of a predefined policy, the determined aggregated demand, and the determined subnet service level agreement.

20. The method of claim 19 , wherein processing the received bandwidth requests further comprises: distributing bandwidth allocated to a first subset between at least one gateway and at least one terminal included in the first subnet in accordance with one or more of an amount of bandwidth requested and a service level agreement associated with said at least one gateway and at least one remote terminal.