Apparatus and method for a virtual hierarchical local area network
View Patent ↗A method and apparatus are provided for creating a virtual hierarchical local area network. The method and apparatus provide a hierarchical framing technique that allows a network architecture to realize a local area network hierarchy within the network. In this manner, a first local area network hierarchy is defined by communication in a first frame format between a first set of network devices and a second set of network devices. A second local area network hierarchy is defined by communication in a second frame format between members of the second set of network devices. The second frame format includes the fields of a frame in the first frame format that is used to communicate between the first set of communication devices and the second set of communication devices.
1. A packet-forwarding apparatus for use in a network comprising network devices, the apparatus comprising,
a storage for storing an address table having a number of entries comprising data link layer addresses for the network devices;
an input to receive a first frame in a first frame format, the first frame format comprising a first data link layer header,
wherein the first frame format represents a first tier of data link layer addresses in the network such that the network has a hierarchy achieved through tiered data link layer addressing;
a framing mechanism to encapsulate the first frame with a second data link layer header to form a second frame format, the second frame format representing a second tier of data link layer addresses in the network hierarchy;
an output to forward the frame in the second frame format toward a destination electronic device; and
a processor for updating the address table, wherein the number of entries in the address table increases linearly for each network device with a data link layer address that is associated with the second tier of the network hierarchy added to the network.
2. The apparatus of claim 1 , wherein the framing mechanism adds a trailer to the first frame to form the second frame.
3. The apparatus of claim 1 , wherein the apparatus is a switch.
4. The apparatus of claim 1 , wherein the output forwards the frame in the second frame format based on a destination address from the first frame format.
5. The apparatus of claim 1 , wherein the framing mechanism encapsulates the first frame independent of the location of the apparatus in the network hierarchy.
6. A device readable medium holding device readable instructions for performing a method in an electronic device for use in a network comprising network devices, the electronic device storing an address table having a number of entries comprising data link layer addresses for the network devices, the method comprising the steps of,
parsing a portion of a first frame in a first frame format received on an input of the electronic device to identify a destination address of the frame, the first frame format having a first data link layer source address and a first data link layer destination address, wherein the first frame format represents a first tier of data link layer addresses in the network such that the network has a hierarchy achieved through tiered data link layer addressing;
formatting the frame in the first frame format into a second frame format in the electronic device, wherein the second frame format represents a second tier of data link layer addresses in the network hierarchy, the second frame format having a second data link layer source address and a second data link layer destination address;
forwarding the frame in the second frame format toward a destination electronic device; and
updating the address table, wherein the number of entries in the address table increases linearly for each network device with a data link layer address that is associated with the second tier of the network hierarchy added to the network.
7. The medium of claim 6 , wherein the step of formatting comprises the step of appending a trailer to the frame in the first frame format.
8. The medium of claim 6 , wherein the step of formatting comprises the step of encapsulating the frame in the first frame format to format the frame into the second frame format.
9. The medium of claim 6 , wherein the first frame format includes a first MAC source address and a first MAC destination address.
10. The medium of claim 6 , wherein the second frame format includes a second MAC source address and a second MAC destination address.
11. The medium of claim 6 further comprising the step of, adding a label to the frame in the second frame format.
12. The medium of claim 6 further comprising the steps of,
receiving one or more of the frames in the second frame format from another electronic device associated with the network; and
decapsulating one of the received frames in the second frame format to return the received frame to the first frame format.
13. The medium of claim 12 further comprising the step of, forwarding the first frame in the first format to the destination address identified in the destination address field of the frame in the first frame format.
14. The medium of claim 6 , wherein the step of forwarding the frame in the second frame format is performed based on a destination address from the first frame format.
15. The medium of claim 6 , wherein the step of formatting the frame in the first frame format into a second frame format is performed independent of the location of the electronic device in the network hierarchy.
16. A method performed in an electronic device for use in a network comprising network devices, the electronic device storing an address table having a number of entries comprising data link layer addresses for the network devices, the method comprising the steps of,
parsing a portion of a first frame in a first frame format received on an input of the electronic device to identify a destination address of the frame, the first frame format having a first data link layer source address and a first data link layer destination address, wherein the first frame format represents a first tier of data link layer addresses in the network such that the network has a hierarchy achieved through tiered data link layer addressing;
formatting the frame in the first frame format into a second frame format in the electronic device, wherein the second frame format represents a second tier of data link layer addresses in the network hierarchy, the second frame format having a second data link layer source address and a second data link layer destination address;
forwarding the frame in the second frame format toward a destination electronic device; and
updating the address table, wherein the number of entries in the address table increases linearly for each network device with a data link layer address that is associated with the second tier of the network hierarchy added to the network.
17. The method of claim 16 , wherein the step of formatting comprises the step of appending a trailer to the frame in the first frame format.
18. The method of claim 16 , wherein the step of formatting comprises the step of encapsulating the frame in the first frame format to format the frame into the second frame format.
19. The method of claim 16 , wherein the first frame format includes a first MAC source address and a first MAC destination address.
20. The method of claim 16 , wherein the second frame format includes a second MAC source address and a second MAC destination address.
21. The method of claim 16 further comprising the step of, adding a label to the frame in the second format.
22. The method of claim 16 further comprising the steps of,
receiving one or more of the frames in the second frame format from another electronic device associated with the network; and
decapsulating one of the received frames in the second frame format to return the received frame to the first frame format.
23. The method of claim 22 further comprising the step of, forwarding the frame in the first format to the destination address identified in the destination address field of the frame in the first frame format.
24. The method of claim 16 , wherein he step of forwarding the frame in the second frame format is performed based on a destination address from the first frame format.
25. The method of claim 16 , wherein the step of formatting the frame in the first frame format into a second frame format is performed independent of the location of the electronic device in the network hierarchy.