Connection and packet level multiplexing between network links

• US 6,243,379 B1
• Filed: 04/04/1997
• Issued: 06/05/2001
• Est. Priority Date: 04/04/1997
• Status: Expired due to Fees

• Current Assignee: Ramp Networks, Inc.
• Original Assignee: Ramp Networks, Inc.
• Inventors: Gurajapu, Suresh, Bathina, Raghu, Veerina, Mahesh
• Primary Examiner(s): Martin-Wallace, Valencia
• Assistant Examiner(s): Nguyen, Kim T.
• Application Number:
  US08/835,072
• Time in Patent Office: 1,523 Days
• Field of Search: 370/400, 370/389, 370/401, 370/402, 370/404, 370/406, 370/408, 370/410, 395/200.3, 395/200, 395/200.79
• US Class Current: 370/389
• CPC Class Codes: H04L 12/46 Interconnection of networks
• CPC Class Codes: H04L 2101/663 Transport layer addresses, e.g. aspects of transmission control protocol [TCP] or user datagram protocol [UDP] ports
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/2517 using port numbers

Abstract

Router circuit, provides Internet protocol (IP) address translation to enable connection or packet-level multiplexing over multiple single-user IP address account links. Connection-level multiplexing (CLM) provide between LAN and WAN addresses outbound packet transfer by replacing private packet source IP address and port number with said external IP address port number, and inbound packet transfer by replacing external packet destination IP address and port number with private IP address and port number. Look-up table provides bi-directional translation or effective multiplexing of IP addresses and port assignments for incoming or outgoing packets. Packet-level multiplexing (PLM) provides between LAN1 and LAN2 addresses outbound packet processing, wherein destination IP address and port number are replaced with external IP address and port number, and inbound packet processing, wherein source IP address and port number are replaced with internal IP address and port number. Link or port allocation are optimizable according to round-robin or bandwidth loading algorithm.

Claims

1. A computer network for digital packet communication comprising:

a first network having at least one first processor, each first processor having a first address;

a second network having at least one second processor, each second processor having a second address; and

a network module for coupling the first network and the second network, the network module comprising an outbound handler, an incoming handler, an IP translation table, an IP router, a plurality of wide area network interfaces connecting to a plurality of corresponding modems to form a plurality of links, wherein the outbound handler checking the IP translation table to select a link for an outbound packet by modifying destination IP address and destination port number of the outbound packet wherein the incoming handler checking the IP translation table for an incoming packet and either dropping the incoming packet if the incoming packet is not found in the IP translation table or modifying destination IP address and destination port number of the incoming packet if the incoming packet is found in the IP translation table.

2. A computer network comprising:

a local area network having a plurality of processors, each processor having an internal Internet Protocol (IP) address;

a wide area network having a plurality of Internet Service Providers (ISP); and

a connection circuit for coupling the local area network and the wide area network, the connection circuit comprising an outbound handler, an incoming handler, an IP translation table, an IP router, a plurality of wide area network interfaces connecting to a plurality of corresponding modems to form a plurality of links, wherein the outbound handler checking the IP translation table to select a link for an outbound packet by modifying destination IP address and destination port number of the outbound packet wherein the incoming handler checking the IP translation table for an incoming packet and either dropping the incoming packet if the incoming packet is not found in the IP translation table or modifying destination IP address and destination port number of the incoming packet if the incoming packet is found in the IP translation table.

9. The computer network of claim 2 wherein:

said translating means modifies a source IP address to be a provided external IP address.

3. A method for outbound packet transfer from processors in a local area network to Internet Service Providers in a wide area network, the method comprising the steps of:

receiving from a plurality of processors in a local area network a plurality of outbound packets;

checking an IP translation table to determine a link from a plurality of links to route an outbound packet;

modifying the destination IP address and port number of the outbound packet; and

sending the modified outbound packet via the selected link to a single-user IP account of an Internet Service Provider in a wide area network.

10. The method of claim 3 wherein:

a source IP address and port number are replaced by a valid IP address and port number which are obtained from a look-up table.

11. The method of claim 3 wherein:

one or more of the outbound packets correspond with a network access instruction for browsing an Internet website over a plurality of Internet user accounts.

4. A method for inbound packet transfer from Internet Service Providers in a wide area network processors in a local area network, the method comprising the steps of:

receiving from a plurality of Internet Service Providers (ISPs) in a wide area network a plurality of inbound packets;

checking the IP translation table to determine a link from a plurality of links to route an inbound packet;

modifying each inbound packet by replacing its destination Internet protocol (IP) address and port number respectively with an internal IP address and port number; and

sending modified inbound packets to at least one processor in a local area network via the selected link to a single-user ISP accounts.

12. The method of claim 4 wherein:

one or more of the received inbound packets comprise a response from a browser request to access a network source for downloading data, the response being received over the same link over which the browser request was sent.

13. The method of claim 4 wherein:

the internal IP address and port number are obtained from a digital memory which stores a plurality of IP addresses and port numbers, thereby effectively enabling multiplexed access simultaneously between one or more processors in the local area network over multiple separate single-user links and one or more ISPs in the wide area network.

5. Apparatus for connecting local-area networks comprising:

a router for sending packets over a plurality of single-user links connectable between at least one processor in a first local area network (LAN) and at least one processor in a second LAN; and

a multiplexing module couples to the router a network module for coupling the first network and the second network, the multiplexing module comprising an outbound handler, an incoming handler, an IP translation table, a plurality of wide area network interfaces connecting to a plurality of corresponding modems to form a plurality of links, wherein the outbound handler checking the IP translation table to select a link for an outbound packet by modifying destination IP address and destination port number of the outbound packet wherein the incoming handler checking the IP translation table for an incoming packet and either dropping the incoming packet if the incoming packet is not found in the IP translation table or modifying destination IP address and destination port number of the incoming packet if the incoming packet is found in the IP translation table.

14. The apparatus of claim 5 wherein:

the multiplexing module comprises a look-up table for storing one or more Internet Protocol (IP) addresses for programmably modifying one or more routing addresses associated with sending packets from the router separately through a first and second single-user links.

6. A method for packet processing comprising the steps of:

providing a look-up table in a memory having at least one entry representing a network connection between a first processor in a first network and a second processor in a second network, each entry comprising a source Internet protocol (IP) address and port, a valid IP address and port, and a destination address IP address and port;

receiving a plurality of packets for routing between the first network and the second network;

checking an IP translation table to determine a link from a plurality of links to route an outbound packet; and

updating the look-up table to include updated entries corresponding to the received packets, the updated entries representing connections between the first and second networks through a plurality of single-user links provided therebetween,

wherein the connections programmably provide multiplexed access simultaneously between one or more processors in the first network and one or more processors in the second network using a plurality of single-user Internet accounts, each single-user Internet account corresponding separately with a different single-user link, whereby a plurality of users in the first network may access the second network simultaneously, the first network having a limited number of IP addresses, and the number of users accessing the limited number of IP addresses is larger than the number of available IP addresses.

7. A method for outbound packet transfer between local area networks, the method comprising the steps of:

receiving at least one outbound packet for transfer from at least one first processor in a first local area network (LAN) to at least one second processor in a second LAN through a plurality of single-user links provided selectably for separately multiplexed access over different single-user links coupled simultaneously therebetween;

checking an IP translation table to determine a link from a plurality of links to route an outbound packet;

modifying the received outbound packet by replacing its destination Internet protocol (IP) address and port number respectively with a remote IP address and port number corresponding to a second processor in the second LAN; and

sending the modified outbound packet to the corresponding second processor in the second LAN, whereby a plurality of users in the first LAN may access the second LAN simultaneously, the first LAN having a limited number of IP addresses, and the number of users accessing the limited number of IP addresses is larger than the number of available IP addresses.

8. A method for inbound packet transfer between local area networks, the method comprising the step of:

receiving at least one inbound packet for transfer from at least one first processor in a first local area network (LAN) to at least one second processor in a second LAN through a plurality of single-user links provided selectably for separately multiplexed access over different single-user links coupled simultaneously therebetween;

checking an IP translation table to determine a link from a plurality of links to route an outbound packet;

modifying the received inbound packet by replacing its source Internet protocol (IP) address and port number respectively with an internal IP address and port number corresponding to a second processor in the second LAN; and

sending the modified inbound packet to the corresponding second processor in the second LAN, whereby a plurality of users in the first LAN may access the second LAN simultaneously, the first LAN having a limited number of IP addresses, and the number of users accessing the limited number of IP addresses is larger than the number of available IP addresses.