System and method for transparent virtual routing

• US 8,451,833 B2
• Filed: 12/14/2007
• Issued: 05/28/2013
• Est. Priority Date: 05/14/2004
• Status: Expired due to Fees

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Inventors: Kolli, Raja, Mead, Garrett, Reister, John, Shaver, Christopher J., Sun, Wendell, Tiedeman, Mark
• Primary Examiner(s): Rinehart, Mark
• Assistant Examiner(s): HOPKINS, MATTHEW A
• Application Number:
  US11/956,652
• Publication Number:
  US 20080151906A1
• Time in Patent Office: 1,992 Days
• Field of Search: 370/270, 370/389, 370/292, 370/390, 370/395.64, 370/397, 370/465, 370/466, 370/473, 370/432, 370/404, 379/27.01, 709/220, 709/221, 725/106, 725/114, 725/138, 725/118
• US Class Current: 370/389
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• CPC Class Codes: H04L 12/289 Single service
• CPC Class Codes: H04L 2101/668 Internet protocol [IP] address subnets
• CPC Class Codes: H04L 61/50 Address allocation

Abstract

A transparent routing device disposed within an access network configured in accordance with one or more lower-layer protocols is disclosed herein. The device includes a set of subscriber-side ports. Each of the subscriber-side ports is associated with a plurality of virtual subscriber-side interfaces disposed to effectively terminate a corresponding plurality of subscriber-side connections with subscriber host devices served by the access network. The device further includes at least one network-side port through which communication occurs with an external network in accordance with a higher-layer protocol. A routing table is configured to establish a correspondence between network addresses of the subscriber host devices and the plurality of virtual subscriber-side interfaces. During operation of the device, packets received through the at least one network-side port are forwarded to corresponding ones of the virtual subscriber-side interfaces based upon network addresses of the packets.

Claims

1. A method for generating an IP-based routing table for use by a transparent routing device disposed within an access network configured in accordance with one or more lower-layer protocols, wherein the transparent routing device comprises a plurality of subscriber-side ports and at least one network-side port, and wherein the transparent routing device is configured to route both upstream and downstream network traffic, said method comprising:

receiving a message through a virtual subscriber-side interface that is defined by said transparent routing device and associated with one of the plurality of subscriber-side ports, the message comprising a request; and

creating an association within the IP-based routing table between an IP address associated with the message, and said virtual subscriber-side interface;

wherein the IP-based routing table is associated with a transparent virtual routing group of the transparent routing device; and

wherein the transparent routing device is able to automatically configure the IP-based routing table by determining IP addresses of a plurality of subscriber hosts associated with the transparent virtual routing group.

2. The method of claim 1, said method further comprising:

wherein the message comprises an address resolution request destined for an IP-based network from a subscriber host within said access network;

inspecting said address resolution request so as to identify an IP address of said subscriber host included within said address resolution request; and

wherein the step of creating an association comprises creating the association within the IP-based routing table between said IP address and said virtual subscriber-side interface.

3. The method of claim 2 wherein said IP-based routing table is associated with a first set of virtual subscriber-side interfaces of said transparent routing device, said method further including generating an additional IP-based routing table associated with a second set of virtual subscriber-side interfaces of said transparent routing device.

4. The method of claim 1, wherein the step of receiving a message comprises receiving the message from a subscriber host served by said access network and through the virtual subscriber-side interface defined by said transparent routing device, the message comprising a DHCP request destined for a DHCP server;

said method further comprising;

generating an augmented DHCP request including at least a client identifier associated with said subscriber host;

forwarding the DHCP request to the DHCP server;

receiving, from the DHCP server, a DHCP reply; and

inspecting said DHCP reply so as to identify an IP address which has been assigned to said subscriber host;

wherein the step of creating an association comprises creating the association within the IP-based routing table between said IP address and said virtual subscriber-side interface.

5. The method of claim 4 further including forwarding the DHCP reply to said subscriber host through said virtual subscriber-side interface.

6. The method of claim 4 wherein said augmented DHCP request further includes relay agent information.

7. The method of claim 4 further including inspecting said DHCP reply so as to determine a duration of assignment of said IP address to said subscriber host.

8. The method of claim 4 wherein said IP-based routing table is associated with a first set of virtual subscriber-side interfaces of said transparent routing device, said method further including generating an additional IP-based routing table associated with a second set of virtual subscriber-side interfaces of said transparent routing device.

9. A method for generating an IP-based routing table for use by a transparent routing device disposed within an access network configured in accordance with one or more lower-layer protocols, wherein the transparent routing device comprises a plurality of subscriber-side ports and a network-side port, and is configured to route both upstream and downstream network traffic, and wherein the IP-based routing table is associated with a transparent virtual routing group of the transparent routing device, said method comprising:

receiving a message through a network-side interface that is defined by said transparent routing device and associated with the network-side port, the message comprising an IP packet received from an IP-based network and destined for a subscriber host within said access network;

identifying a destination IP address of said IP packet; and

if no association exists within the IP-based routing table between the destination IP address and a virtual subscriber-side interface defined by said transparent routing device;

generating a request for identifying the subscriber host having the destination IP address;

transmitting the request to a plurality of hosts via a plurality of virtual subscriber-side interfaces of said transparent routing device;

receiving a reply, via one of the plurality of virtual subscriber-side interfaces, from the subscriber host having the destination IP address; and

creating an association within the IP-based routing table between the destination IP address and the one of the plurality of virtual subscriber-side interfaces.