System and method for providing secure multicasting across virtual private networks

1. A method for providing a secure multicast of data across an unsecured network, the method comprising:

receiving, at an IPSec virtual private network device (IVD), a join message identifying at least one private multicast group;

identifying, by the IVD, a public multicast group of the unsecured network that is mapped to the private multicast group;

generating, by the IVD, a membership report specifying the public multicast group;

inserting a public IVD address of the IVD into a source field of the membership report;

sending the membership report to the unsecured network;

creating an IPSec tunnel through the unsecured network to a network element;

generating an IPSec encrypted control message specifying the private multicast group; and

sending the encrypted control message through the tunnel to allow the network element to decrypt the encrypted control message and send the decrypted control message to another network element.

2. The method of claim 1 , wherein the join message is a control message.

3. The method of claim 2 , wherein the control message is a Protocol Independent Multicast control message.

4. The method of claim 1 , wherein the join message is a membership report.

5. The method of claim 4 , wherein the membership report is an Internet Group Message Protocol membership report.

6. The method of claim 1 , wherein the network element is an encryption device.

7. The method of claim 1 , further comprising:

receiving the encrypted control message from the secure tunnel;

decrypting the encrypted control message; and

sending the decrypted control message to a second network element.

8. A system for securely transmitting multicast data across a public network, the system comprising:

a first encryptor network element comprising an IPSec virtual private network device (IVD) and operable to

receive a join message from a first network element, the join message identifying at least one private multicast group,

identify a public multicast group of the unsecured network that is mapped to the private multicast group,

generate a membership report specifying the public multicast group,

send the membership report to the public network,

generate an IPSec encrypted control message specifying the private multicast group,

insert a public IVD address of the IVD into a source field of the membership report,

send the encrypted control message through the secure tunnel to the second encryptor network element to allow the second encryptor network element to decrypt the encrypted control message and send the decrypted control message to another network element.

9. The system of claim 8 , wherein the first network element is selected from a group consisting of:

a router;

a switch;

a gateway;

a bridge;

a load-balancer; and

a firewall.

10. The system of claim 8 , wherein the join message is a control message.

11. The system of claim 10 , wherein the control message is a Protocol Independent Multicast control message.

12. The system of claim 8 , wherein the first network element is a multicast receiver.

13. The system of claim 12 , wherein the join message is a membership report.

14. The system of claim 13 , wherein the membership report is an Internet Group Message Protocol membership report.

15. A non-transitory computer readable medium storing software for securely transmitting multicast data across a public network, the software being embodied in the non-transitory computer readable medium and comprising code such that when executed is operable to:

receive a join message identifying at least one private multicast group;

identify a public multicast group of the unsecured network that is mapped to the private multicast group;

generate a membership report specifying the public multicast group;

insert a public IVD address of the IVD into a source field of the membership report;

send the membership report to the unsecured network;

create an IPSec tunnel through the unsecured network to a network element;

generate an IPSec encrypted control message specifying the private multicast group; and

send the encrypted control message through the tunnel to allow the network element to decrypt the encrypted control message and send the decrypted control message to another network element.

16. The non-transitory computer readable medium of claim 15 , wherein the join message is a control message.

17. The non-transitory computer readable Medium of claim 16 , wherein the control message is a Protocol Independent Multicast control message.

18. The non-transitory computer readable medium of claim 15 , wherein the join message is a membership report.

19. The non-transitory computer readable medium of claim 18 , wherein the membership report is an Internet Group Message Protocol membership report.

20. The non-transitory computer readable medium of claim 15 , wherein the network element is an encryption device.