Cost reduction of NAT connection state keep-alive

• US 8,553,701 B2
• Filed: 08/02/2011
• Issued: 10/08/2013
• Est. Priority Date: 03/12/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Herzog, Shai
• Primary Examiner(s): Sefcheck, Gregory
• Assistant Examiner(s): MITCHELL, DANIEL D
• Application Number:
  US13/196,337
• Publication Number:
  US 20110286373A1
• Time in Patent Office: 798 Days
• Field of Search: None
• US Class Current: 370/395.2
• CPC Class Codes: H04L 61/2553 Binding renewal aspects, e.g. using keep-alive messages
• CPC Class Codes: H04L 61/256 NAT traversal
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 76/25 Maintenance of established connections
• CPC Class Codes: H04W 92/02 Inter-networking arrangements
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Keep-alive processing for NAT devices and reducing power consumption in wireless clients. A server driven keep-alive mechanism facilitates keep-alive messages to a NAT device currently providing a connection to a mobile client to refresh the NAT state, thereby reducing or eliminating power consumption in a wireless device to respond to the connection with keep-alive packets. In one instance, keep-alive packets are sent to the NAT device to reset the NAT timeout timer, and then to the mobile client. The client responds only when expected keep-alive packets are not received at the client. In another instance, keep-alive packets reset the NAT timer to maintain the connection but are dropped or self-destruct before reaching the mobile client thereby providing the optimum power conservation in the mobile device. Thus, the client is not forced into extra client activity to send or receive wireless data, thereby draining the battery.

Claims

1. A method of managing communications connections, comprising acts of:

in an enhanced keep-alive packet processing mode, receiving a keep-alive packet from an external network at a network boundary component;

resetting a connection timer associated with a communications connection between a wireless device on an internal network and the external network in response to receiving the keep-alive packet from the external network;

monitoring the communications connection based on utilization of the enhanced keep-alive packet processing mode; and

automatically changing to a standard keep-alive packet processing mode based on reduced quality in a connection state of the communications connection.

2. The method of claim 1, further comprising:

receiving an indication from the wireless device if the wireless device does not receive the keep-alive packet.

3. The method of claim 1, further comprising:

computing a time-to-live (TTL) value based on a transit time of the keep-alive packet from a source of the keep-alive packet to the network boundary component; and

changing the TTL value in the keep-alive packet.

4. The method of claim 1, further comprising:

selectively terminating the keep-alive packet at the network boundary component based on a nTTL value associated with the keep-alive packet.

5. The method of claim 1, wherein:

the network boundary component is a NAT router; and

the method further comprises providing an indication that the NAT router can handle the enhanced keep-alive packet processing mode.

6. The method of claim 1, further comprising:

performing the method for each of multiple communications connections.

7. The method of claim 1, further comprising:

performing IP address translation for the communications connection.

8. The method of claim 1, wherein the keep-alive packet includes a protocol identifier, a source IP address, a source port identifier, a destination IP address, and a destination port identifier.

9. A computer-readable memory having instructions stored therein for performing operations that manage communications connections, the operations comprising:

in an enhanced keep-alive packet processing mode, receiving a keep-alive packet from an external network at a network boundary component;

resetting a connection timer associated with a communications connection between a wireless device on an internal network and the external network in response to receiving the keep-alive packet from the external network;

monitoring the communications connection based on utilization of the enhanced keep-alive packet processing mode; and

automatically changing to a standard keep-alive packet processing mode based on reduced quality in a connection state of the communications connection.

10. The computer-readable memory of claim 9, wherein the operations further comprise:

receiving an indication from the wireless device if the wireless device does not receive the keep-alive packet.

11. The computer-readable memory of claim 9, wherein the operations further comprise:

computing a time-to-live (TTL) value based on a transit time of the keep-alive packet from a source of the keep-alive packet to the apparatus; and

changing the TTL value in the keep-alive packet.

12. The computer-readable memory of claim 9, wherein the operations further comprise:

selectively terminating the keep-alive packet at the apparatus based on a nTTL value associated with the keep-alive packet.

13. The computer-readable memory of claim 9, wherein:

the network boundary component is a NAT router; and

the operations further comprise providing an indication that the NAT router can handle the enhanced keep-alive packet processing mode.

14. The computer-readable memory of claim 9, wherein the operations further comprise:

performing IP address translation for the communications connection.

15. The computer-readable memory of claim 9, wherein the keep-alive packet includes a protocol identifier, a source IP address, a source port identifier, a destination IP address, and a destination port identifier.

16. An apparatus for managing a communications connection, comprising:

a memory and a processor that are respectively configured to store and execute instructions that;

establish an IP connection between an external network and a wireless device of an internal network via the apparatus;

receive a keep-alive packet from the external network into the apparatus;

reset a connection timer in response to receiving the keep-alive packet from the external network;

maintain the IP connection between the external network and the wireless device via the apparatus based on receiving keep-alive packets from the external network;

monitor the IP connection between the external network and the wireless device based on utilization of an enhanced keep-alive packet processing mode; and

automatically change to a standard keep-alive packet processing mode based on a reduced quality in a connection state between the external network and the wireless device.

17. The apparatus of claim 16, wherein the instructions also:

receive an indication from the wireless device if the keep-alive packet is not received at the wireless device.

18. The apparatus of claim 16, wherein the instructions also:

compute a time-to-live (TTL) value based on transit time of the keep-alive packet to the apparatus; and

set the TTL value in the keep-alive packet for dropping the packet.

19. The apparatus of claim 16, wherein the instructions also:

selectively terminate keep-alive packet based on an nTTL value associated with the keep-alive packet.

20. The apparatus of claim 16, wherein the instructions also:

perform IP address translation for the IP connection.