Virtual bridge

• US 20060233168A1
• Filed: 04/19/2005
• Published: 10/19/2006
• Est. Priority Date: 04/19/2005
• Status: Active Grant

• Current Assignee: Tahoe Research Limited (f/k/a Learndale Limited) (Vector Capital Corporation)
• Original Assignee: Intel Corporation
• Inventors: Lewites, Saul, Garg, Ajay
• Granted Patent: US 7,561,531 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• CPC Class Codes: H04L 12/462 LAN interconnection over a bridge based backbone

Abstract

A method and apparatus establish an address of a frame as being associated with a physical device or a virtual device. If the frame is associated with a virtual device, the address of the frame may be established as being associated with a local virtual device or a remote virtual device. Establishing the nature and location of the device may provide routing by a virtual bridge.

Claims

1. A method comprising:

establishing an address of a frame as being associated with a physical device or a virtual device; and

if the frame is associated with a virtual device, establishing the address of the frame as being associated with a local virtual device relative to a virtual bridge or a remote virtual device, to provide routing by the virtual bridge.

2. The method of claim 1, wherein establishing an address of a frame as being associated with a physical device or a virtual device includes assigning a portion of the address of the frame a value such that the value is different from values assigned to physical devices.

3. The method of claim 2, wherein the value is assigned to the first byte of a MAC address of a virtual network interface card, the value of the first byte being different from a value of a first byte of assigned organizationally unique identifiers.

4. The method of claim 3, wherein the method includes:

assigning an index to a second byte of the MAC address, the index belonging to a table that maintains pointers to virtual network interface card objects; and

assigning four bytes of an address of a physical network interface card to four bytes of the MAC address, the physical network interface card being associated with the virtual network interface card.

5. The method of claim 1, wherein establishing an address of a frame as being associated with a physical device or a virtual device includes checking whether a first set of information in the address of the frame is associated with a physical device or a virtual device, and establishing the address of a frame as being associated with a local virtual device or a remote virtual device includes checking whether a second set of information in the address is associated with an address of a local physical or a remote physical device.

6. The method of claim 1, wherein establishing an address of a frame as being associated with a physical device or a virtual device includes checking a first byte of a destination MAC address to determine if the first byte is assigned to a physical network interface card.

7. The method of claim 6, wherein checking a first byte of a destination MAC address includes comparing the first byte against assigned identifiers.

8. The method of claim 6, wherein establishing the address of a frame as being associated with a local virtual device or a remote virtual device, if the frame is associated with a virtual device, includes checking four bytes of the destination MAC address to determine if the four bytes are associated with a local or remote physical network interface card.

9. The method of claim 8, wherein the method includes accessing a routing table at an index specified by a second byte of the destination MAC address.

10. The method of claim 9, wherein the method includes forwarding the frame to an appropriate local virtual network interface card after accessing the routing table.

11. The method of claim 8, wherein the method includes sending the frame to a physical network interface card if checking four bytes of the destination MAC address determines that the address of the frame is associated with a remote virtual network interface card.

12. An apparatus comprising:

a controller; and

a virtual machine monitor executable by the controller, the virtual machine monitor operable to direct data flow between a network interface card and a set of virtual machines, the virtual machine monitor having a virtual bridge to make routing decisions, the virtual machine monitor operable to;

establish an address of a frame as being associated with a physical device or a virtual device; and

if the frame is associated with a virtual device, establish the address of the frame as being associated with a local virtual device relative to a virtual bridge or a remote virtual device, to provide routing by the virtual bridge.

13. The apparatus of claim 12, wherein to establish an address of a frame as being associated with a physical device or a virtual device includes checking whether a first set of information in the address of the frame is associated with a physical device or a virtual device, and to establish the address of a frame as being associated with a local virtual device or a remote virtual device includes checking whether a second set of information in the address is associated with an address of a local physical device or a remote physical device.

14. The apparatus of claim 12, wherein to establish an address of a frame as being associated with a physical device or a virtual device includes checking a first byte of a destination MAC address to determine if the first byte is assigned to a physical network interface card.

15. The apparatus of claim 14, wherein to establish the address of a frame as being associated with a local virtual device or a remote virtual device, if the frame is associated with a virtual device, includes checking four bytes of the destination MAC address to determine if the four bytes are associated with a local or remote physical network interface card.

16. The apparatus of claim 15, wherein the virtual bridge is operable to access a routing table at an index specified by a second byte of the destination MAC address and to forward the frame to an appropriate local virtual network interface card after accessing the routing table.

17. The apparatus of claim 15, wherein the virtual bridge is operable to send the frame to a physical network interface card if checking four bytes of the destination MAC address determines that the address of the frame is associated with a remote virtual network interface card.

18. The apparatus of claim 12, wherein the virtual machine monitor operable to establish an address of a frame as being associated with a physical device or a virtual device includes the virtual machine monitor operable to assign a portion of the address of the frame a value such that the value is different from assigned to a physical device.

19. The apparatus of claim 18, wherein the value is assigned to the first byte of a MAC address of a virtual network interface card, the value of the first byte being different from a value of a first byte of assigned organizationally unique identifiers.

20. The apparatus of claim 19, wherein the virtual machine monitor is operable to:

assign an index to a second byte of the MAC address, the index belonging to a table that maintains pointers to virtual network interface card objects; and

assign four bytes of an address of a physical network interface card to four bytes of the MAC address, the physical network interface card being associated with the virtual network interface card.

21. A computer readable medium that stores instructions, which when performed by a machine, cause the machine to:

establish an address of a frame as being associated with a physical device or a virtual device; and

if the frame is associated with a virtual device, establish the address of the frame as being associated with a local virtual device relative to a virtual bridge or a remote virtual device, to provide routing by the virtual bridge.

22. The computer readable medium of claim 21, wherein to establish an address of a frame as being associated with a physical device or a virtual device includes assigning a value to a first byte of a MAC address of a virtual network interface card, the value of the first byte being different than a value of a first byte of assigned organizationally unique identifiers of physical virtual network interface cards.

23. The computer readable medium of claim 22, wherein the instructions, which when performed by a machine, cause the machine to:

assign an index to a second byte of the MAC address, the index belonging to a table that maintains pointers to virtual network interface card objects; and

assign four bytes of an address of a physical network interface card to four bytes of the MAC address, the physical network interface card being associated with the virtual network interface card.

24. The computer readable medium of claim 21, wherein to establish an address of a frame as being associated with a physical device or a virtual device includes checking a first byte of a destination MAC address to determine if the first byte has a valve different than assigned to physical network interface cards and to establish the address of a frame as being associated with a local virtual device or a remote virtual device, if the frame is associated with a virtual device, includes checking four bytes of the destination MAC address to determine if the four bytes are associated with a local or remote physical network interface card.

25. The computer readable medium of claim 24, wherein the instructions, which when performed by a machine, cause the machine to:

access a routing table at an index specified by a second byte of the destination MAC address; and

forward the frame to an appropriate local virtual network interface card after accessing the routing table.

26. A system comprising:

a processor;

a network interface;

a parallel bus to which the processor and the network interface are communicatively coupled; and

a virtual machine monitor executable by the processor, the virtual machine monitor operable to direct data flow between the network interface and a set of virtual devices, the virtual machine monitor having a virtual bridge to make routing decisions, the virtual machine monitor operable to;

establish an address of a frame as being associated with a physical device or a virtual device; and

if the frame is associated with a virtual device, establish the address of the frame as being associated with a local virtual device or a remote virtual device, to provide routing by a virtual bridge.

27. The system of claim 26, wherein to establish an address of a frame as being associated with a physical device or a virtual device includes assigning a value to a first byte of a MAC address of a virtual network interface, the value of the first byte being different than a value of a first byte of assigned organizationally unique identifiers of physical network interfaces.

28. The system of claim 27, wherein the virtual machine monitor is operable to:

assign an index to a second byte of the MAC address, the index belonging to a table that maintains pointers to virtual network interface objects; and

assign four bytes of an address of a physical network interface to four bytes of the MAC address, the physical network interface being associated with the virtual network interface.

29. The system of claim 26, wherein the virtual bridge is operable to:

check a first byte of a destination MAC address to determine if the first byte has a valve different than assigned to physical network interfaces; and

if the frame is associated with a virtual network interface, check four bytes of the destination MAC address to determine if the four bytes are associated with a local or remote network interface.

30. The system of claim 29, wherein the virtual bridge is operable to:

access a routing table at an index specified by a second byte of the destination MAC address; and

forward the frame to an appropriate local virtual network interface after accessing the routing table.