Methods and Systems for Network Address Translation Management

• US 20090073987A1
• Filed: 11/14/2007
• Published: 03/19/2009
• Est. Priority Date: 09/14/2007
• Status: Active Grant

• Current Assignee: AT&T Knowledge Ventures, L.P. (AT&T, Inc.)
• Original Assignee: AT&T Knowledge Ventures, L.P. (AT&T, Inc.)
• Inventors: Li, Zhi, Savoor, Raghvendra, Li, Jian
• Granted Patent: US 8,233,488 B2
• Time in Patent Office: Days
• US Class Current: 370/395.310
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/36 by determining packet size, e.g. maximum transfer unit [MTU]
• CPC Class Codes: H04L 61/255 Maintenance or indexing of mapping tables

Abstract

A method for network address translation (NAT) includes providing a first and a second NAT table. The method further includes receiving a network packet and classifying the network packet based on a type of network traffic. Additionally, an entry is added to the first NAT table based on the classification of the network packet.

Claims

1. A method for network address translation (NAT), the method comprising:

providing a first NAT table and a second NAT table, the first NAT table including entries for network traffic of a first type between a public network and a private network and the second NAT table including entries for network traffic of a second type between the public network and the private network;

receiving a first network packet;

determining the first network packet corresponds to the first type of network traffic; and

adding a first entry to the first NAT table.

2. The method of claim 1, further comprising limiting the first NAT table to a predefined size.

3. The method of claim 2, further comprising providing an interface for changing the predefined size.

4. The method of claim 1, further comprising limiting the first type of network traffic to a predefined packet rate.

5. The method of claim 1, further comprising limiting the first type of network traffic to a first portion of a bandwidth to guarantee a predefined second portion of the bandwidth is available to network traffic of the second type.

6. The method of claim 1, further comprising receiving a second network packet;

determining the second network packet corresponds to the second type of network traffic; and

adding a second entry to the second NAT table.

7. The method of claim 1, further comprising removing the first entry from the first NAT table after a first timeout interval and removing the second entry from the second NAT table after a second timeout interval.

8. The method of claim 7, further comprising providing an interface for altering the first timeout interval or the second timeout interval.

9. The method of claim 1, further comprising receiving a third network packet;

determining the third network packet corresponds to the first type of network traffic; and

retrieving a third entry from the first NAT table.

10. The method of claim 1, wherein the first entry includes an address and a port of a first device on the private network, an address and a port of a second device on the public network, and an address and a port of the gateway.

11. A gateway comprising:

a memory configured to include a first NAT table and a second NAT table, the first NAT table including entries for network traffic of a first type between a public network and a private network and the second NAT table including entries for network traffic of a second type between the public network and the private network;

a processor configured to;

receive a first network packet;

determine the first network packet corresponds to the first type of network traffic; and

add a first entry to the first NAT table.

12. The gateway of claim 11, wherein the processor is further configured to limit the first type of network traffic to a predefined packet rate.

13. The gateway of claim 11, wherein the processor is further configured to limit the first type of network traffic to a first portion of a bandwidth to guarantee a predefined second portion of the bandwidth is available to network traffic of a second type.

14. The gateway of claim 11, wherein the processor is further configured to receive a second network packet;

determine the second network packet corresponds to the second type of network traffic; and

add a second entry to the second NAT table.

15. The gateway of claim 14, wherein the first NAT table has a first timeout value and the second NAT table has a second timeout value.

16. The gateway of claim 11, further comprising an expansion slot for increasing the size of the memory.

17. A method for network address translation (NAT), the method comprising:

providing a NAT table, the NAT table including plurality of entries for network traffic between a public network and a private network, a first portion of the plurality of entries including a type designation corresponding to a first type of network traffic and a second portion of the plurality of entries including a type designation corresponding to a second type of network traffic;

receiving a first network packet;

determining the first network packet corresponds to the first type of network traffic; and

adding a first entry to the NAT table, the entry including a type designation corresponding to the first type of network traffic.

18. The method of claim 17, further comprising limiting the first portion to a predefined size.

19. The method of claim 17, further comprising limiting the first type of network traffic to a predefined packet rate.

20. The method of claim 17, further comprising limiting the first type of network traffic to a first bandwidth to guarantee a predefined second bandwidth is available to the second type of network traffic.

21. The method of claim 17, further comprising receiving a second network packet;

determining the second network packet corresponds to the second type of network traffic; and

adding a second entry to the NAT table, the entry including a type designation corresponding to the second type of network traffic.

22. The method of claim 17, further comprising removing the first entry after a first timeout interval and removing the second entry after a second timeout interval.

23. A gateway comprising:

a memory configured to include a NAT table, the first NAT table including a plurality of entries for network traffic between a public network and a private network, a first portion of the plurality of entries including a first type designation corresponding to a first type of network traffic and a second portion of the plurality of entries including a second type designation corresponding to a second type of network traffic;

a processor configured to;

receive a first network packet;

determine the first network traffic corresponds to the first type of network traffic; and

add a first entry to the NAT table, the entry including the first type designation.

24. The gateway of claim 23, wherein the processor is further configured to limit the first type of network traffic to a predefined packet rate.

25. The gateway of claim 23, wherein the processor is further configured to limit the first type of network traffic to a first bandwidth to guarantee a predefined second bandwidth is available to the second type of network traffic.