Combining routers to increase concurrency and redundancy in external network access

• US 6,493,341 B1
• Filed: 12/29/2000
• Issued: 12/10/2002
• Est. Priority Date: 12/31/1999
• Status: Expired due to Term

• Current Assignee: Fatpipe Networks Private Ltd.
• Original Assignee: Ragula Systems Incorporated
• Inventors: Datta, Sanchaita, Bhaskar, Ragula
• Primary Examiner(s): Jung, Min
• Application Number:
  US09/751,590
• Time in Patent Office: 711 Days
• Field of Search: 370/392, 370/401, 370/402, 370/403, 370/404, 370/405, 370/409, 370/410, 370/462, 370/503, 370/217, 370/465, 370/229, 709/238, 709/242
• US Class Current: 370/392
• CPC Class Codes: H04L 12/5692 Selection among different networks
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 45/58 Association of routers
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/10 of different types
• CPC Class Codes: H04L 61/35 involving non-standard use of addresses for implementing network functionalities, e.g. coding subscription information within the address or functional addressing, i.e. assigning an address to a function
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures

Abstract

Methods, configured storage media, and systems are provided for increasing bandwidth between a local area network (“LAN”) and other networks by using multiple routers on the given LAN. Data packets are multiplexed between the routers using a novel variation on the standard SYN packet synchronization protocol, and other components. On receiving data destined for an external network, a controller or gateway computer will direct the data to the appropriate router. In addition to providing higher speed connections, the invention provides better fault tolerance in the form of redundant connections from the originating LAN to a wide area network such as the Internet.

Claims

1. A method for combining routers to provide flexible increased concurrency for external access by a local area computer network, the method comprising the steps of:

identifying at least two routers for the local area network, each identified router having its own IP address and its own physical address;

receiving a SYN request in the form of a SYN packet;

selecting one of the identified routers by determining that consequent use of the selected router will tend to increase concurrent operation of identified routers by sending subsequent access requests and their corresponding responses through the selected router and thereby helping provide improved external access to the computer network through identified routers; and

responding to the SYN request with a modified SYN packet that specifies the physical address of the selected router, the selected router not necessarily having the IP address specified in the unmodified original SYN request.

2. The method of claim 1, wherein the identifying step is performed at a first location in a local area network which is a sub-network, and the identifying step comprises identifying an IP address and a physical address for at least two routers within the local area network.

3. The method of claim 1, wherein the selecting step comprises multiplexing between identified routers without regard to current router loads.

4. The method of claim 1, wherein the selecting step comprises the steps of obtaining indications of the current loads of identified routers and then choosing the selected router by applying at least one load balancing criterion.

5. The method of claim 1, wherein the receiving step receives the SYN request at a machine whose IP address is specified in the request and that machine is not the selected router.

6. The method of claim 1, wherein the SYN request specifies the IP address of a first identified router, and that first identified router is not the selected router.

7. The method of claim 1, further comprising an exchanging step in which a controller at a source network exchanges command data packets with a controller at a destination network, whereby at least one of networks obtains at least one address of a router at the other network.

8. A controller for combining routers to provide increased concurrency in external access to a computer network, the controller comprising:

a router identifier for identifying at least two routers for a LAN, each identified router having its own IP address and its own physical address;

a router selector for selecting between identified routers, the router selector making its selection in a manner which increases concurrent operation of identified routers and thereby helps provide improved external access to the computer network through identified routers; and

a SYN modifier which provides modifed SYN requests that contain the IP address of an identified router, each response specifying the physical address of an identified router which was selected by the router selector.

9. The controller of claim 8, wherein the SYN modifier provides a response to a SYN request that contains the IP address of a machine running the controller, and the response specifies the physical address of an identified router selected by the router selector instead of specifying the physical address of the machine running the controller.

10. The controller of claim 8, wherein the SYN modifier provides a response to a SYN request that contains the IP address of a first identified router, and the response specifies the physical address of a second identified router selected by the router selector instead of specifying the physical address of the first identified router.

11. The controller of claim 8, wherein the controller consists of software containing executable instructions and data.

12. The controller of claim 8, wherein the controller consists of hardware and software, the hardware includes at least one processor and memory accessible to the processor, and the software contains executable instructions and data which are stored in the memory and which guide operation of the processor.

13. The controller of claim 8, in combination with a computer which is running at least part of the controller as software.

14. The controller of claim 8, in combination with at least two identified routers which have been identified by the router identifier.

15. The controller of claim 8, in combination with at least one network client which generates at least one SYN request to which the SYN modifier provides a response.

16. The controller and network client combination of claim 15, in combination with a computer which is running at least part of the controller as software, at least two identified routers which have been identified by the router identifier, and at least one additional network client which generates at least one SYN request to which the SYN modifier provides a response.

17. The controller of claim 8, characterized in that the controller helps provide improved external access to the computer network through identified routers by providing higher speed connections.

18. The controller of claim 8, characterized in that the controller helps provide improved external access to the computer network through identified routers by providing redundant connections from the originating LAN to the wide area network, thereby increasing the system'"'"'s fault tolerance.

19. The controller of claim 18, wherein a router stops functioning, and the controller software automatically redirects the data destined for the external network to at least one other functioning router.

20. A computer storage medium having a configuration that represents data and instructions which will cause performance of method steps for combining routers to provide increased concurrency for external access by a computer network, the method comprising the steps of:

identifying at least two routers, each identified router having its own address;

receiving a SYN request containing an IP address;

selecting one of the identified routers; and

modifying the SYN request so that it specifies the physical address of the selected router, the physical address in the modified SYN request identifying a different machine than the machine identified by the IP address in the original request.

21. The configured storage medium of claim 20, wherein the identifying step identifies an IP address and a physical address for each of at least two routers within a local area network.

22. The configured storage medium of claim 20, wherein the selecting step comprises multiplexing between identified routers with regard to past router selections.

23. The configured storage medium of claim 20, wherein the selecting step comprises the steps of obtaining indications of the measured loads on identified routers and then choosing the selected router by applying at least one load balancing criterion.