Power saving operation of always-connected wireless roaming

• US 8,149,747 B2
• Filed: 09/28/2007
• Issued: 04/03/2012
• Est. Priority Date: 09/28/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel Corporation
• Inventors: Sood, Kapil, James, Tsai
• Primary Examiner(s): Sam, Phirin
• Application Number:
  US11/864,688
• Publication Number:
  US 20090086660A1
• Time in Patent Office: 1,649 Days
• Field of Search: None
• US Class Current: 370/311
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 52/0251 using monitoring of local events, e.g. events related to user activity
• CPC Class Codes: H04W 52/0293 having a sub-controller with a low clock frequency switching on and off a main controller with a high clock frequency
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Methods and apparatuses enable maintaining wireless connectivity while the wireless client device is in a power save mode. The system includes a host operating system (OS) that handles wireless connections while the device is executing in normal operation, and an embedded agent that handles the wireless connections when the device switches to power saving operation and the host OS switches to a sleep or standby state. The system detects a change in the power save mode and triggers an exchange of session context information between the host OS and the embedded agent (from the host OS to the embedded agent when the system enters the power save mode, and from the embedded agent to the host OS when the system returns to normal operation from the power save mode). The system also triggers the switching of management consistent with the passing of session context information.

Claims

1. A method in a wireless network client device comprising:

detecting a change in a power saving operating mode within the wireless network client device,

where a host operating system on a host hardware platform of the wireless network client device manages network access of the wireless network client in normal operation, and

where an embedded agent that has independent operation from the host OS manages network access of the wireless network client in power saving operation;

wherein managing network access includes maintaining an active network access session with a wireless network including managing connectivity and security configuration information of the wireless network client necessary to keep the network access session active;

exchanging session context between the host OS and the embedded agent of the wireless network client device responsive to detecting the change in the power saving operating mode, the session context defining a network access session of the wireless network client device with a wireless network, the session context including the security configuration information; and

switching management of roaming for network access for the wireless network client device between the host OS and the embedded agent in conjunction with exchanging the session context responsive to detecting the change in the power saving operating mode.

2. The method of claim 1, wherein detecting the change in power saving operating mode comprises determining that the host OS is resuming normal operation after being in a deep power save mode;

and

wherein exchanging the session context between the host OS and the embedded agent comprises uploading the session context from the embedded agent to the host OS.

3. The method of claim 2, wherein determining that the host OS is resuming normal operation after being in the deep power save mode comprises:

determining the host OS is awakening from standby.

4. The method of claim 1, wherein exchanging the session context between the host OS and the embedded agent comprises:

exchanging information related to open network connections, including keying information.

5. The method of claim 1, wherein exchanging the session context between the host OS and the embedded agent comprises:

exchanging the session context between the host OS and one of a virtual machine independent of the host OS or an embedded firmware agent executing on network interface hardware.

6. The method of claim 1, wherein exchanging the session context between the host OS and the embedded agent comprises:

exchanging the session context between the host OS and one of an embedded microcontroller on a host hardware platform or a dedicated processing core of a multi-core processing unit.

7. The method of claim 1, wherein switching management of roaming for the wireless network client device comprises:

switching management of roaming that is compatible with the Institute of Electrical and Electronics Engineers (IEEE) 802.11r standard.

8. An article of manufacture comprising a machine-readable storage medium having content stored thereon to provide instructions which when executed cause a machine to perform operations including:

detecting initiation of a power saving operating mode in a host operating system (OS) on a host hardware platform of a wireless network client device that connects to a wireless broadband data network,

where the host OS manages network access of the wireless network client in normal operation, and

where an embedded agent that has independent operation from the host OS manages network access of the wireless network client in power saving operation;

wherein managing network access includes maintaining an active network access session with a wireless network including managing connectivity and security configuration information of the wireless network client necessary to keep the network access session active;

transferring session context related to a network access session of the wireless network client device from the host OS to the embedded agent on the wireless network client device in response to detecting the initiation of the power saving operating mode, the session context defining the network access session of the wireless network client device with the wireless broadband data network, the session context including the security configuration information; and

performing roaming on behalf of the wireless network client device with the embedded agent while the host OS is in the power saving operating mode.

9. The article of manufacture of claim 8, wherein the content to provide instructions for transferring session context from the host OS to the embedded agent comprises content to provide instructions for

transferring session context via a wireless device driver to the embedded agent.

10. The article of manufacture of claim 8, wherein the content to provide instructions for transferring session context from the host OS to the embedded agent comprises content to provide instructions for

transferring session context from the host OS to one of a virtual machine independent of the host OS, an embedded firmware agent executing on network interface hardware, an embedded microcontroller on a host hardware platform, or a dedicated processing core of a multi-core processing unit.

11. The article of manufacture of claim 8, wherein the content to provide instructions for performing the roaming comprises content to provide instructions for

executing wireless connection management algorithms locally on the embedded agent.

12. The article of manufacture of claim 8, the content to further provide instructions to result in the machine performing operations including:

monitoring the wireless network client device for an event that will trigger the host OS to switch operation from the power saving operating mode to a normal operating mode.

13. The article of manufacture of claim 12, the content to further provide instructions to result in the machine performing operations including:

passing updated session context from the embedded agent to the host OS responsive to detecting an event that will trigger the host OS to switch to the normal operation mode.

14. A wireless client device comprising:

a host hardware platform to execute a host operating system (OS), the host OS to manage wireless connections in a normal operating mode, including maintaining the wireless connections with a wireless access point;

an embedded agent to operate independently of the host OS, the embedded agent to manage the wireless connections in a power saving mode when the host OS is not managing the wireless connections, including maintaining the wireless connections with the wireless access point and roaming to a different wireless access point;

wherein managing the wireless connections network access includes maintaining an active network access session with a wireless network including managing connectivity and security configuration information of the wireless network client necessary to keep the network access session active;

transfer logic to switch management of the wireless connections between the host OS and the embedded agent depending on the operating mode, and trigger an exchange of session context that defines a network access session of the wireless client device, the session context including the security configuration information; and

network interface hardware to maintain a physical link to a current access point.

15. The wireless client device of claim 14, wherein the embedded agent comprises an agent executed on one of a processor core, a microprocessor on a hardware platform of the wireless client device, or a network interface card.

16. The wireless client device of claim 14, wherein the embedded agent managing the wireless connections comprises maintaining security parameters of the wireless connections.

17. The wireless client device of claim 14, wherein the embedded agent managing the wireless connections comprises maintaining quality of service (QoS) parameters of the wireless connections.

18. The wireless client device of claim 14, wherein the transfer logic triggers an exchange of multiple session contexts for multiple sessions for the wireless client device.