Method and apparatus for supporting sub networks in a MoCA network

1. A method for establishing sub networks in a communication network having a main network, the method comprising:

receiving an admission request message from a node, wherein the admission request messages comprises:

at least a first bit that specifies whether the node is a preferred network coordinator (PNC); and

at least a second bit, different from the first bit, that specifies whether the node is a secured and preferred network coordinator (SPNC) different from a PNC, wherein an SPNC is a node that is capable of concurrently performing the functions of a secured network coordinator of a main network of a premises and of performing the functions of a secured network coordinator of a sub network of the main network, wherein:

the main network comprises a first number of nodes and has a main network password; and

the sub network comprises a second number of nodes, which is a subset of the first number of nodes, and has a sub network password different from the main network password; and

in response to the admission request message, sending an admission response message to at least the node comprising information indicating which of the nodes in the network are secured and preferred network coordinators (SPNCs).

2. The method of claim 1 , wherein the at least a first bit and the at least a second bit of the received admission request message are bits of a NODE PROTOCOL SUPPORT (NPS) field of the received admission request message.

3. The method of claim 1 , comprising:

prior to receiving the admission request, receiving a discovery request message;

if privacy is enabled for a sub network of the main network and privacy is not enabled for the main network, sending a discovery response message including a Permanent Salt in response to the received discovery request message;

decrypting the received admission request with a static key derived from the Permanent Salt and a main network password; and

sending the admission response message only if the contents of the received admission request could be interpreted after decrypting.

4. The method of claim 1 , comprising sending dynamic sub network keys associated with at least one sub network, where the dynamic sub network keys are encrypted with a static sub network key derived from a Permanent Salt of the main network and a sub network password, different from the main network password, associated with the sub network with which the encrypted dynamic sub network key is to be used.

5. The method of claim 1 , comprising sending dynamic sub network keys associated with at least one sub network within a response message, wherein the entire response message is encrypted with a static sub network key derived from a Permanent Salt of the main network and a sub network password, different from the main network password, associated with the sub network with which the encrypted dynamic sub network key is to be used.

6. The method of claim 4 , wherein said sending dynamic sub network keys comprises:

receiving a key request message encrypted with the static sub network key; and

sending a key response message in response to receipt of the key request message, the key response message including the encrypted dynamic sub network keys.

7. The method of claim 1 , comprising sending on the network a subnetwork parameters distribution request message providing information about sub networks.

8. The method of claim 7 , comprising:

receiving a sub network key response message carrying sub network dynamic keys, different from main network dynamic keys, for sub networks identified in the subnetwork parameters distribution request message, where the subnetwork key response message is encrypted with a sub network dynamic key;

sending a subnetwork key acknowledgement indicating that the subnetwork key response message was received; and

sending a media access plan (MAP) message indicating that privacy is in use for the subnetworks.

9. The method of claim 1 , comprising selecting a node that is an SPNC to perform a network coordinator (NC) function if the at least a second bit of the admission request message indicates that the node is an SPNC, the current NC is not an SPNC and an NC selection process is performed.

10. The method of claim 1 , wherein the at least a second bit is only a single bit of the admission request message.

11. A node for utilization with a communication network, the node comprising:

an electrical circuit comprising:

a physical layer (PHY) comprising an interface that receives and sends information over a medium; and

a processor coupled to the PHY,

wherein the at least one electrical circuit operates to, at least:

receive an admission request message from a node, wherein the admission request message comprises:

at least a first bit that specifies whether the node is a preferred network coordinator; and

at least a second bit, different from the first bit, that specifies whether the node is a secured and preferred network coordinator (SPNC) different from a PNC, wherein an SPNC is a node that is capable of concurrently performing the functions of a secured network coordinator of a main network of a premises and of performing the functions of a secured network coordinator of a sub network of the main network, where:

the main network comprises a first number of nodes and has a main network password; and

the sub network comprises a second number of nodes, which is a subset of the first number of nodes, and has a sub network password different from the main network password; and

in response to the admission request message, send an admission response message to at least the node comprising information indicating which of the nodes in the network are secured and preferred network coordinators (SPNCs).

12. The node of claim 11 , wherein the at least a first bit and the at least a second bit of the received admission request message are bits of a NODE PROTOCOL SUPPORT (NPS) field of the received admission request message.

13. The node of claim 11 , wherein the electrical circuit operates to:

prior to receiving the admission request, receive a discovery request message;

if privacy is enabled for a sub network of the main network and privacy is not enabled for the main network, send a discovery response message including a Permanent Salt in response to the received discovery request message;

decrypt the received admission request with a static key derived from the Permanent Salt and a main network password; and

send the admission response message only if the contents of the received admission request could be interpreted after decrypting.

14. The node of claim 11 , wherein the electrical circuit operates to send dynamic sub network keys associated with at least one sub network, where the dynamic sub network keys are encrypted with a static sub network key derived from a Permanent Salt of the main network and a sub network password, different from the main network password, associated with the sub network with which the encrypted dynamic sub network key is to be used.

15. The node of claim 11 , wherein the electrical circuit operates to send dynamic sub network keys associated with at least one sub network within a response message, wherein the entire response message is encrypted with a static sub network key derived from a Permanent Salt of the main network and a sub network password, different from the main network password, associated with the sub network with which the encrypted dynamic sub network key is to be used.

16. The node of claim 14 , wherein the electrical circuit operates to send the dynamic sub network keys by, at least in part, operating to:

receive a key request message encrypted with the static sub network key; and

send a key response message in response to receipt of the key request message, the key response message including the encrypted dynamic sub network keys.

17. The node of claim 11 , wherein the electrical circuit operates to send on the network a subnetwork parameters distribution request message providing information about sub networks of the network.

18. The node of claim 17 , wherein the electrical circuit operates to:

receive a sub network key response message carrying sub network dynamic keys, different from main network dynamic keys, for sub networks identified in the subnetwork parameters distribution request message, where the subnetwork key response message is encrypted with a sub network dynamic key;

send a subnetwork key acknowledgement indicating that the subnetwork key response message was received; and

send a media access plan (MAP) message indicating that privacy is in use for the subnetworks.

19. The node of claim 11 , wherein the electrical circuit operates to select a node that is an SPNC to perform a network coordinator (NC) function if the at least a second bit of the admission request message indicates that the node is an SPNC, the current NC is not an SPNC and an NC selection process is performed.

20. The node of claim 11 , wherein the at least a second bit is only a single bit of the admission request message.