VIRTUAL NETWORK INTERFACE

• US 20090129385A1
• Filed: 08/03/2005
• Published: 05/21/2009
• Est. Priority Date: 09/17/2004
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Wray, Michael John, Dalton, Christopher I.
• Granted Patent: US 8,213,429 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling

Abstract

A virtual network has network interfaces coupled by a multipoint tunnel (100) through a forwarding network (40), each interface having a forwarding address in an address space of the forwarding network, each network interface having a reconfigurable address mapper (320) for determining a forwarding address for a packet, and encapsulating the packet with its forwarding address so that the forwarding network can forward the data packet transparent to its destination address. This makes the virtual network more agile since changes to the virtual network can be achieved by reconfiguring the corresponding forwarding addresses without needing to set up new tunnels new routing to these different tunnels. The forwarding network need not be aware of the virtual network and so no adaptation of the forwarding network or specialised hardware is needed.

Claims

1. A network interface for a virtual network, the virtual network having a number of remote interfaces coupled by a multipoint tunnel through a forwarding network, each remote interface having a forwarding address in an address space of the forwarding network, the network interface being arranged to receive data packets to be sent across the virtual network, the data packets each having a destination address in an address space of the virtual network, the network interface having an address mapper arranged to determine which of the forwarding addresses to use for each packet, according to its destination address, the corresponding forwarding addresses being reconfigurable, and the network interface being arranged to encapsulate each data packet with its forwarding address so that the forwarding network can forward the data packet transparent to its destination address, to implement the multipoint tunnel.

2. The interface of claim 1, the address mapper being arranged to determine the corresponding address locally without reference to a remote centralised map.

3. The interface of claim 1 the address mapper having a stored mapping of addresses for determining the corresponding address.

4. The interface of claim 1, for use with multiple virtual networks, the address mapper being arranged to determine the corresponding address according to which virtual network the data packet belongs to.

5. The interface of claim 1, for use with multiple users, and arranged to receive inbound tunnelled packets from the forwarding network and use the destination address of the packets to route each packet to the correct one of the users.

6. The interface of claim 3, for use with multiple virtual networks, the stored mapping having an input for an identifier of the virtual network.

7. The network interface of claim 1, arranged for use with multiple virtual networks, and arranged to encapsulate the data packet with an indication of which of the virtual networks the data packet belongs to.

8. The network interface of claim 1, arranged such that a user of the virtual network is unaware of the corresponding forwarding address.

9. The network interface of claim 1, arranged for use with multiple virtual networks, and arranged to determine which of the multiple virtual networks a data packet belongs to without reference to a user.

10. The network interface of claim 1, arranged to set a source address of the data packet without reference to a user.

11. The network interface of claim 1, arranged to intercept all the data packets sent from one or more virtual machines.

12. The network interface of claim 1, for use with virtual machines, the interface using an operating system to provide a bridge from each of the virtual machines to the interface.

13. The interface of claim 1, the virtual network using a network standard according to ISO layer 2.

14. The interface of claim 1, the forwarding network using a network standard according to ISO layer 3.

15. The interface of claim 1, being arranged to configure the stored mapping by sending a discovery request over the forwarding network.

16. The interface of claim 1, being arranged to identify if the packet data is a multicast packet and if so send it to a predetermined multicast address in the forwarding network.

17. A computer network having a first physical server arranged to run the interface of claim 1, and a second physical server coupled to the first physical server by a physical link, and arranged to run a remote interface, the forwarding network being arranged to use the physical link.

18. The network of claim 17, having a VLAN interface to a virtual local area network.

19. The network of claim 18, for use with multiple virtual networks, and the VLAN interface being arranged to determine from a received packet an identifier of a virtual network for that packet, and use the identifier to determine an identifier of a corresponding VLAN, for use in forwarding the packet over the VLAN.

20. A method of sending data packets across a virtual network, the virtual network having a number of remote interfaces coupled by a multipoint tunnel through a forwarding network, each remote interface having a forwarding address in an address space of the forwarding network, the data packets each having a destination address in an address space of the virtual network, the method having the steps of identifying the destination address of each data packet to be sent, determining which of the forwarding addresses to use for each packet, according to its destination address, by using a reconfigurable address mapper, and encapsulating each data packet with its forwarding address so that the forwarding network can forward the data packet transparent to its destination address, to implement the multipoint tunnel.