WO2012009407A2

WO2012009407A2 - Voip call setup integration with power saving mode support

Info

Publication number: WO2012009407A2
Application number: PCT/US2011/043810
Authority: WO
Inventors: Tricci So; Wen Luo; Yangwei Tu
Original assignee: Zte Usa Inc.; Zte Corporation
Priority date: 2010-07-14
Filing date: 2011-07-13
Publication date: 2012-01-19
Also published as: WO2012009407A3

Abstract

Aspects of the present invention are directed towards methods and apparatus for adjusting an application timer to integrate an application service with power saving support. An application server receives an incoming call request from a calling device. The application server queries an Authentication, Authorization, Accounting server (AAA) server for paging performance information associated with a target device. The application server adjusts the application layer timer to a period of time longer than an expected duration for the calling device to receive an incoming call response from the target device, wherein the expected duration is based upon the paging performance information.

Description

S P E C I F I C A T I O N

VOIP CALL SETUP INTEGRATION WITH POWER SAVING MODE

SUPPORT

PRIORITY

[001] Priority is claimed to U.S. Provisional Patent Application No.

61/364,258, filed July 14, 2010, and U.S. Provisional Patent Application No. 61/365,036, filed July 16, 2010, the disclosures of which are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION [002] The field of the present invention is Session Initiation Protocol

(SlP)-based Voice over Internet Protocol (VoIP) systems, and more specifically, SIP-based VoIP systems with power saving mode support.

BACKGROUND

[003] VoIP service is transacted at a service layer which is above an access transport layer of an access network. Through the access network, a mobile device can interact with an SIP-based server, (e.g., a proxy server at the backend), to establish voice communication between the proxy server and the mobile device. The access network may include a wireless access network such as WiMAX Access Service Network (ASN). Figure 1 is a block diagram illustrating the concept service and transport layer integration to support voice and other multi-media services. Although the discussion herein is directed primarily toward VoIP support, aspects of the present invention may also be directed to other multi-media services that may be implemented using the SIP protocol. [004] Due to high processing requirements associated with emerging wireless technologies, battery consumption performance has become critical to ensure that batteries used in new generations of mobile devices have a satisfactory life-span while still providing sufficient power to enable the mobile devices to provide advanced wireless services. Thus, effective and efficient power saving support is critical for these new generations of mobile devices.

[005] Power saving operations on the mobile terminal involves functions implemented on the mobile device, as well as, support functions implemented on the attached access network. The mobile device enters its power saving mode due to a lack of local activity. However, the mobile device may remain in its owner's possession as the owner travels to different geographical areas that are within a coverage area of the access network. As incoming data could be targeted to the mobile device at anytime, it is important for the access network to keep track of the current location of the mobile device so that the access network can alert the mobile device as necessary.

[006] Because there is no way for the access network to predict exactly when incoming data will be sent to a mobile device, the mobile device is required to wake up in regular periodic intervals to provide updated location information to the access network. When the mobile device checks in with the access network, it also checks to see if there is any outstanding data waiting to be transmitted to the mobile device. When the access network receives incoming data which is targeted to the mobile device, it pages the mobile device. The access network pages the last known location that was updated by the mobile device. The paging occurs at the next alert interval during which the mobile device is expected to come out from an idle mode. Thus, the access network paging cycle interval for paging the mobile device is aligned with the duration that the mobile comes out from the idle mode to perform the location update and to check for outstanding data.

[007] It is important to note that a frequency of when the mobile device comes from the idle mode has a significant impact on the power saving efficiency of the battery used by the mobile device. Although, a mobile device that infrequently comes out from the idle mode affects call setup latency, many operators have recognized that more mobile users prefer to live with a few more seconds of delay during the call setup than to have a battery with a shorter lifespan.

[008] When an incoming service destined for a called party/mobile device of the access network arrives at an application-service core, if the protocol of the service layer requires a deterministic timely response to the calling party, it is important for the application server to know how to fine tune a timer to wait for a called party's response. In the case when the mobile device of the called party is in idle mode, the application layer timer needs to be set to wait long enough for the called party's response. The application server also needs to determine if inserting an interim proxy response, for example a Ring-Back Tone (RBT), towards the calling party is needed.

[009] It should be noted that not all devices attached to the access network are mobile devices. Hence, for some fixed devices, the power saving operations are not applicable. As a result, the application server may not want to extend the application layer timer and may not want to provide the interim response to the calling party indiscriminately. This limits the impact on the call setup performance for fixed devices in order to accommodate the power saving requirements of mobile devices.

[010] Call setup performance is important to operators that compete on network performance differentiation. As a result, operators need to balance the interests of battery life performance and call setup performance

SUMMARY OF THE INVENTION

[011] Aspects of the present invention are directed towards methods and apparatus for adjusting an application timer to integrate an application service with power saving support.

[012] In an aspect of the present invention, at least one application server receives an incoming call request from a calling device. An application server receives an incoming call request from a calling device. The application server queries an Authentication, Authorization, Accounting server (AAA) server for paging performance information associated with a target device. The application server adjusts the application layer timer to a period of time longer than an expected duration for the calling device to receive an incoming call response from the target device, wherein the expected duration is based upon the paging performance information. The paging performance information can be a static value, a target device type, and/or a current operational state of the target device.

[013] Additional aspects and advantages of the improvements will appear from the description of the preferred embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[014] Aspects of the present invention will now be further described in the following more detailed description of the specification when read with reference to the accompanying drawings in which:

[015] Figure 1 is a block diagram depicting separate control layers for transport and application services;

[016] Figure 2 is a signaling diagram illustrating a basic call setup control flow without considering the power saving impact of a target device at a target access network when an incoming call arrives;

[017] Figure 3 is a signaling diagram illustrating integration of a service application with power saving support. A call setup is configured to include a static value representative of an expected paging performance at the target access network, regardless of the target device type or state at the time the incoming call arrives.

[018] Figure 4 is a signaling diagram illustrating integration of a service application with power saving support. A call setup is configured according to the expected paging performance at the target access network based on the target device type, regardless of the target device state at the time an incoming call arrives;

[019] Figure 5 is a signaling diagram illustrating integration of a service application with power saving support. A call setup is configured according to the expected paging performance at the target access network based on the current operational state of the target device at the time an incoming call arrives; [020] Figure 6 is a signaling diagram illustrating integration of a service application with power saving support. A call setup is configured according to the expecting paging performance at the target access network based on the current operational state of the target device at the time an incoming call arrives, wherein the AAA server or HSS queries the target access network to determine the operational state of the target device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[021] Aspects of the present invention enable an application server, for example WiMAX VoIP Service (i.e. WVS) Server, at the called party end to determine how the application layer timer, for example SIP Timer A and/or SIP Timer B, is to be aligned with the expected paging performance, and to provide the interim response to the calling mobile device, if the called mobile device is in idle mode when the incoming call arrives. The "paging

performance" is, for example, "the duration of the paging interval" that is determined by the network to page the mobile device which has subscribed to voice services, in addition to "the duration of the worst case scenario for the mobile device to complete the paging response and the network re-entry procedures," based on the given network's local measurement.

[022] The "paging performance" is, for example, "the duration of the paging interval" that is determined by the network to page the mobile device which has subscribed to voice services, in addition to "the duration of the worst case scenario for the mobile device to complete the paging response and the network re-entry procedures," based on the given network's local measurement. [023] Figure 2 is a signaling diagram illustrating a basic call setup control flow without considering the power saving impact on the target device when an incoming call arrives. The SIP Timer-C that is set to wait for the target device response is generally based on the access network's round trip processing delay and the transport delay. It does not take into consideration the current operational state of the target device.

[024] To integrate the power saving support with an application service at the called domain for those mobile devices to provide a deterministic state response to the calling domain, several aspects of the present invention are provided. These aspects consider the expected paging performance for alerting an idle target device, when needed, to respond to the incoming call setup requests. It should be noted that the expected paging performance in the target network may be influenced by the quality of service (QoS) for the given application service.

[025] Figure 3 is a signaling diagram illustrating integration of a service application with power saving support. A call setup is configured to include a static value associated with the expected paging performance at the target access network, regardless of whether the target device is fixed or mobile, or in active mode or idle mode at the time an incoming call arrives. The target access network configures the application layer timer, for example, SIP Timer A and/or SIP Timer B, to a time that is long enough to incorporate the expected paging performance at the target access network with which the target device is presently associated. The application layer time is also configured to a time that is long enough to insert an interim proxy response to a calling party while waiting for the actual response from the target device. [026] Figure 4 is a signaling diagram illustrating integration of a service application with power saving support. In this aspect, the call setup is configured according to the expected paging performance at the target access network. This call setup is configured based on the target device type (fixed or mobile), regardless of whether the target device is operating in active or idle mode at the time when an incoming call arrives. A serving application server stores the target device type. Prior to the target device making an outgoing call or receiving an incoming call, the target device registers with the serving application server. During the service registration, the server application server queries an Authentication, Authorization, and Accounting (AAA) server or Home Subscriber Server (HSS) about the device type. This device type information drives the decision of the serving application server to set the application layer timer and to provide the interim proxy response to the calling party accordingly. For example, a short timer may be used without considering the paging performance (i.e. t1 only) for a "fixed device". The longer timer considering the paging performance (i.e. t1 + t2(paging performance)) may be used for the mobile device, regardless of whether the mobile device is in an idle mode or active mode, at the time an incoming call arrives.

[027] Figure 5 is a signaling diagram illustrating integration of a service application with power saving support. A call setup is configured according to the expected paging performance at the target access network based on the current operational state of the target device at the time an incoming call arrives. In this aspect, an AAA-server or an HSS has already received notification from the target access network regarding the current operational state of the target device.

[028] When an incoming call setup request (e.g. SIP INVITE message) arrives at the serving application server associated with the target device (e.g. a WVS server of which the target device is registered), the serving application server queries the AAA server/HSS regarding the current operational state of the target device. The serving application server could use can use the target device state query request/response transaction to query the operation state. If the target device is in idle mode, and therefore needs to be paged, the serving application server will then set the application layer timer (e.g. the SIP Timer for the SIP INVITE transaction timeout) to be long enough for the target device to exit from idle mode (i.e. the paging for the target device is successfully completed) to receive the incoming call request. The serving application server then sends a call setup request to the target device. The serving application server could also provide the interim proxy response to the calling device. For example, the server application server can reply with a SIP 180 (ringing) provisional response to the calling device. If the target device is not in idle mode (i.e. in active mode), the application layer timer will be set to the regular response time to wait for the target device's response for the call setup request and the interim proxy response may not be provided to the calling device.

[029] Note that there are various approaches for the AAA-server/HSS to be aware of the current power saving operational status of the device. For example, whenever the device enters or exits into/from the idle mode, the access network informs the AAA-server/ HSS of its operational status. Thus, when the serving application server queries the AAA-server or the HSS, the power saving operational status of the target device will be available for the inquiry. In another example, when the AAA-server or the HSS receives the inquiry from the application server, the AAA-server or the HSS will then query the access network regarding the current power saving operational status of the device prior to responding to the inquiry from the application server. If the target device is fixed, the power saving operation state will be "active". Note that the control flow in the Figure 5 regarding the "Callee Operational Status Query Request and Response" can be sent by the Application/Proxy Server to the AAA-server/HSS before or after the SIP-INVITE:sip.dbaron@18.18.2.4 message is sent to the target device.

[030] Figure 6 is a signaling diagram illustrating integration of a service application with power saving support. The serving application network queries the AAA-server/HSS regarding the current operational status of the target device (i.e. active or idle mode) at the time the incoming call arrives at the target domain. The AAA-server/HSS which in turn queries the target access network regarding the current operational status of the target device. Note that the control flow in the Figure 6 regarding the "Callee

Operational Status Query Request and Response" can be sent by the

Application/Proxy Server to the AAA-server/HSS before or after the SIP- INVITE:sip.dbaron@18.18.2.4 message is sent to the target device.

[031] While embodiments of this invention have been shown and described, it will be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein. The invention, therefore, is not to be restricted except in the spirit of the following claims.

Claims

CLAIMS What is claimed is:

1. A method for adjusting an application layer timer to integrate an application service with power saving support, the method comprising:

receiving, by an application server, an incoming call request from a calling device to a target device;

querying, by the application server, an Authentication, Authorization, Accounting (AAA) server for information associated with the target device; and;

adjusting, by the application server, the application layer timer to a period of time longer than an expected duration based upon the information associated with the target device.

2. The method of claim 1 , wherein the information associated with the target device includes a static value, and the expected duration is a period of time which is shorter than the static value.

3. The method of claim 1 , wherein the information associated with the target device includes a target device type, and the expected duration is a period of time for receiving an incoming call response from the target device.

4. The method of claim 1 , wherein the information associated with the target device includes a current operational state of the target device, and the expected duration is based upon the current operational state.

5. The method of claim 4, wherein the current operational state of the target device is idle mode, and the expected duration is a period of time for paging the target device completion.

6. The method of claim 5, further comprising paging, by the application server, the target device, by sending the incoming call request to a last known location of the target device.

7. The method of claim 5, further comprising sending, by the application server, an interim proxy response to the calling party.

8. An application server for adjusting an application layer timer to integrate an application service with power saving support, the application server configured to:

receive an incoming call request from a calling device;

query an Authentication, Authorization, Accounting (AAA) server for information associated with a target device; and

adjust the application layer timer to a period of time longer than an expected duration based upon the information associated with the target device.

9. The application server of claim 8, wherein the information associated with the target device includes a static value, and the expected duration is a period of time which is shorter than the static value.

10. The application server of claim 8, wherein information associated with the target device includes a target device type, and the expected duration is a period of time for receiving an incoming call response from the target device.

1 1. The application server of claim 8, wherein the information associated with the target device includes a current operational state of the target device, and the expected duration is based upon the current operational state..

12. The application server of claim 1 1 , wherein the current operational state of the target device is idle mode, and the expected duration is a period of time for paging the target device completion.

13. The application server of claim 12, further configured to send the incoming call request to a last known location of the target device to page the target device.

14. The application server of claim 12, further configured to send an interim proxy response to the calling device.

15. An apparatus for adjusting an application layer timer to integrate an application service with power saving support, the method comprising:

means for receiving an incoming call request from a calling device to a target device;

means for querying an Authentication, Authorization, Accounting (AAA) server for information associated with the target device; and

means for adjusting the application layer timer to a time longer than an expected duration based upon the information associated with the target device.

16. The apparatus of claim 15, wherein the information associated with the target device includes a static value, and the expected duration is a period of time which is shorter than the static value.

17. The apparatus of claim 15, wherein the information associated with the target device includes a target device type, and the expected duration is a period of time for receiving an incoming call response from the target device.

18. The apparatus of claim 15, wherein the information associated with the target device includes a current operational state of the target device, and the expected duration is based upon the current operational state.

19. The apparatus of claim 18, wherein the current operational state of the target device is idle mode, and the expected duration is a period of time for paging the target device completion.

20. The apparatus of claim 19, further comprising means for sending the incoming call request to a last known location of the target device to page the target device.

21. The apparatus of claim 19, further comprising means for sending an interim proxy response to the calling party.