CN102868634B

CN102868634B - Method and device for congestion control and user equipment

Info

Publication number: CN102868634B
Application number: CN201110185546.5A
Authority: CN
Inventors: 龙水平; 李小娟
Original assignee: Huawei Device Co Ltd
Current assignee: Global Innovation Polymerization LLC; Tanous Co
Priority date: 2011-07-04
Filing date: 2011-07-04
Publication date: 2015-07-08
Anticipated expiration: 2031-07-04
Also published as: CN102868634A; WO2013004151A1

Abstract

The invention is applicable to the communication field and provides a method and a device for congestion control and user equipment. The method comprises the steps that: the user equipment UE initiates a session management (SM) request or a mobility management (MM) request to a core network; the UE receives a rejection message, containing back-off time, sent by the core network due to SM congestion or MM congestion; and the UE runs a back-off timer according to the back-off time, monitors information of congestion release during the running of the back-off timer, and stops running the back-off timer when the information of congestion release is monitored. According to the invention, the UE monitors information of SM congestion release or MM congestion release during the running of the back-off timer so that the UE can timely acquire the information of network congestion release.

Description

Congestion control method and device and user equipment

Technical Field

The present invention belongs to the field of communications, and in particular, to a method and an apparatus for congestion control, and a user equipment.

Background

Currently, congestion (also called overload) is the most machine-to-machine problem for operators, and therefore, how to effectively control congestion becomes crucial. Nowadays, after the congestion problem is standardized, the congestion is controlled by three types of schemes, which are: a back-off timer, a low priority indication, and an extended access restriction. The congestion control method by the back-off timer is divided into three mechanisms: session Management (SM) congestion control based on an Access Point Name (APN), Mobility Management (MM) congestion control based on an APN, and non-access stratum (NAS) level MM congestion control.

Whether APN based SM congestion control, APN based MM congestion control or generic NAS level MM congestion control, there is a major problem: during the back-off timer running, even if congestion has been relieved or a User Equipment (UE) has moved to a new SGSN or MME, the UE cannot know in time.

Disclosure of Invention

The embodiment of the invention provides a congestion control method, aiming at solving the problem that in the existing mode of controlling congestion by a back-off timer, even if congestion is relieved during the operation of the back-off timer, UE (user equipment) cannot know in time.

In one aspect, a method of congestion control is provided, the method comprising:

user Equipment (UE) initiates a Session Management (SM) request or a Mobility Management (MM) request to a core network;

the UE receives a rejection message which is sent by a core network due to SM congestion or MM congestion and contains a back-off time;

and the UE operates a back-off timer according to the back-off time, monitors the information of congestion relief during the operation period of the back-off timer, and stops the back-off timer if the information of congestion relief is monitored.

In another aspect, a user equipment is provided, which includes:

a request initiating unit, configured to initiate a session management SM request or a mobility management MM request to a core network;

a message receiving unit, configured to receive a rejection message containing a back-off time sent by the core network due to SM congestion or MM congestion;

a congestion detection unit, configured to run a back-off timer according to the back-off time, and monitor congestion relief information during the running period of the back-off timer;

and a back-off stopping unit, configured to stop the back-off timer if the congestion monitoring unit monitors the congestion release information.

Meanwhile, in one aspect of the present invention, a method for congestion control is provided, where the method includes:

when a generic non-access stratum NAS level MM congestion occurs in the core network,

after receiving an MM request sent by User Equipment (UE), returning a rejection message to the UE, wherein the rejection message carries rollback time;

when the back-off time is greater than the sum of the MRT time and the implicit detach time of the mobile reachable timer, the core network adjusts the MRT time and/or the implicit detach time so that the back-off time is smaller than the sum of the MRT time and the implicit detach time.

In another aspect, an apparatus is provided, the apparatus comprising:

a congestion judgment unit for determining whether or not MM congestion of the generic non-access stratum NAS level occurs;

a request receiving unit, configured to, when the congestion determining unit determines that the MM congestion of the generic NAS level occurs, receive a MM request for mobility management sent by a user equipment UE, and then return a rejection message to the UE, where the rejection message carries a backoff time;

and the time keeping unit is used for adjusting the MRT time and/or the implicit detach time when the back-off time is greater than the sum of the MRT time and the implicit detach time of the mobile reachable timer so that the back-off time is less than the sum of the MRT time and the implicit detach time.

In the embodiment of the invention, the information of releasing the network congestion can be timely obtained by the UE by monitoring the information of releasing the congestion during the running period of the back-off timer.

Drawings

Fig. 1 is a flowchart of a congestion control method according to a first embodiment of the present invention;

fig. 2 is a flowchart of a congestion control method according to a second embodiment of the present invention;

fig. 3 is a flowchart of a congestion control method according to a third embodiment of the present invention;

fig. 4 is a flowchart of a congestion control method according to a fourth embodiment of the present invention;

fig. 5 is a flowchart of a congestion control method according to a fifth embodiment of the present invention;

fig. 6 is a flowchart of a congestion control method according to a sixth embodiment of the present invention;

fig. 7 is a schematic diagram of a congestion control apparatus according to a seventh embodiment of the present invention;

fig. 8 is a schematic diagram of a congestion control apparatus according to an eighth embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The embodiment of the invention enables the UE to timely acquire the information of congestion relief by a method that the UE monitors the information of congestion relief during the running period of the back-off timer.

The invention provides a congestion control method, a congestion control device and user equipment, wherein the congestion control method comprises the following steps:

a method of congestion control, the method comprising:

the UE receives a rejection message which is sent by a core network due to SM congestion or MM congestion and contains the back-off time;

Further, the information for monitoring congestion relief during the operation of the back-off timer comprises:

when a preset condition is met, the UE initiates an SM request or an MM request to the core network;

and if the UE receives a message sent by the core network and used for accepting the SM request or the MM request, judging that the congestion relief information is monitored.

Further, the preset condition includes at least one of the following:

the running time of the back-off timer reaches a preset threshold; or

The UE detects a new Routing Area Identifier (RAI); or

The UE detects a new tracking area identity, TAI.

Further, after the UE receives a rejection message containing a back-off time sent by a core network due to SM congestion or MM congestion, the method further includes:

and the UE stores the current routing area identification RAI or the current tracking area identification TAI or a TAI list contained in the rejection message.

Further, the reject message further includes a routing area identity RAI list or a tracking area identity TAI list, where the RAI list indicates a service area of an SGSN and the TAI list indicates a service area of an MME;

the information for monitoring congestion relief during the operation of the back-off timer comprises:

and when the UE moves to a routing area RA outside the RAI list or moves to a tracking area TA outside the TAI list, judging to monitor the information of congestion relief.

Further, when the core network is congested by an SM based on an APN of an access point name, the information for monitoring congestion relief during the operation of the back-off timer includes:

the UE monitors information of SM congestion relief based on APN through MM flow or SM flow or paging flow or Notification flow initiated by the core network; or,

the UE monitors information of SM congestion relief based on APN through RAU or TAU or periodic RAU or periodic TAU;

or,

when the core network is congested with a generic non-access stratum (NAS) level MM, the information for monitoring congestion relief during the operation of the back-off timer includes:

when the UE moves to a new routing area RA or a new tracking area TA, the UE initiates a routing area update RAU or a tracking area update TAU;

monitoring the information of the congestion relief of the general NAS-level MM through an SM flow or a called service flow or a paging flow initiated by the core network;

or,

when the UE moves to a new routing area RA or a new tracking area TA, the UE initiates a routing area update RAU request or a tracking area update TAU request, and if the UE receives a message sent by the core network and accepting the request, the information of congestion relief is judged to be monitored.

Further, the core network comprises one or more serving general packet radio service technology support nodes, SGSN, and/or mobility management entities, MME.

A user equipment, comprising:

a message receiving unit, configured to receive a rejection message containing a back-off time, which is sent by the core network due to SM congestion or MM congestion;

a congestion monitoring unit, configured to run a back-off timer according to the back-off time, and monitor congestion relief information during the running period of the back-off timer;

and the back-off stopping unit is used for stopping the back-off timer if the congestion monitoring unit monitors the information of congestion relief.

Further, at least any one of the following is included:

a condition monitoring module, configured to initiate an SM request or an MM request to the core network when a preset condition is met, and determine to monitor congestion relief information if a message sent by the core network to accept the SM request or the MM request is received, where the preset condition includes that a back-off timer running time reaches a preset threshold and/or a new routing area identity RAI or a new tracking area identity TAI is detected;

an SGSN/MME mobility module, configured to determine that congestion relief information is monitored when the ue moves to a new serving gprs support node SGSN or a new mobility management entity MME in the core network;

a first flow monitoring module, configured to monitor, through an MM flow, an SM flow, a paging flow, or a Notification flow initiated by the core network, information about SM congestion relief based on an APN of an access point name, or monitor, through an RAU, a TAU, a periodic RAU, or a periodic TAU, information about SM congestion relief based on an APN;

a second flow monitoring module, configured to initiate an SM flow or a called service flow or a paging flow through the core network to monitor information of releasing MM congestion in a generic non-access stratum NAS level;

a third flow monitoring module, configured to determine that congestion relief information is monitored if a message sent by the core network to accept a routing area update RAU request or a tracking area update TAU request is received when the ue moves to a new routing area RA or a tracking area TA and the ue initiates the RAU request or the tracking area update TAU request.

In another aspect, a congestion control method is provided, the method including:

when a core network generates general non-access stratum (NAS) level Mobility Management (MM) congestion, after receiving an MM request sent by User Equipment (UE), returning a rejection message to the UE, wherein the rejection message carries rollback time;

An apparatus, the apparatus comprising:

a congestion determination unit for determining whether or not a generic non-access stratum (NAS) level Mobility Management (MM) congestion occurs;

a request receiving unit, configured to, when the congestion determining unit determines that the MM congestion of the generic NAS level occurs, receive an MM request sent by a user equipment UE, and then return a rejection message to the UE, where the rejection message carries a backoff time;

and the time keeping unit is used for adjusting the MRT time and/or the implicit detach time when the back-off time is greater than the sum of the MRT time and the implicit detach time of the mobile reachable timer so as to enable the back-off time to be less than the sum of the MRT time and the implicit detach time.

In order to explain the technical means of the present invention, the following description will be given by way of specific examples.

The first embodiment is as follows:

fig. 1 is a flowchart of a congestion control method according to a first embodiment of the present invention, and for convenience of description, only the parts related to the embodiment of the present invention are shown.

1. The core network determines that SM congestion or MM congestion has occurred.

In the embodiment of the present invention, SM congestion or MM congestion includes, but is not limited to: APN based SM congestion, or APN based MM congestion, or generic NAS level MM congestion. The core network includes one or more serving general packet radio service technology Support nodes (SGSN) and/or Mobility Management Entities (MME).

The UE initiates an SM request or MM request to the core network.

3. The core network rejects the SM request or MM request initiated by the UE and returns the back-off time.

In the embodiment of the present invention, because the core network has already determined that SM congestion or MM congestion occurs at this time, after receiving the SM request or MM request sent by the UE, the core network sends a message rejecting the SM request or MM request sent by the UE, where the message carries the backoff time.

And 4, the UE operates a back-off timer according to the back-off time and monitors the information of congestion relief during the operation of the back-off timer.

In the embodiment of the invention, after receiving the back-off time returned by the core network, the UE operates a back-off timer according to the back-off time and forbids SM or MM processes. The UE monitors whether SM congestion or MM congestion is relieved or not during the running period of the back-off timer, so that the UE can know the information of SM congestion or MM congestion relief in time.

In the embodiment of the present invention, there are various methods for the UE to monitor the SM congestion or MM congestion relief information, which are respectively:

A. when the preset condition is met, the UE initiates an SM request or an MM request, and judges whether the information of congestion relief is monitored by receiving a message of receiving the SM request or the MM request sent by a core network.

In the embodiment of the invention, under a preset condition, if an SM request or an MM request initiated by a UE attempt is accepted by a core network, the congestion relief information is monitored, and the SM congestion or the MM congestion is relieved by the core network; if the SM request or MM request initiated by the UE is not accepted by the core network, it indicates that the congestion release information is not monitored, and the core network does not release the SM congestion or MM congestion. Wherein the preset conditions comprise at least one of the following conditions: the running time of the back-off timer reaches a preset threshold, or the UE detects a new RAI (Routing Area identity), or the UE detects a new TAI (Tracking Area identity), or the UE has a need to initiate an SM or MM procedure. The preset thresholds include, but are not limited to: one quarter over time, one half over time, three quarters over time, etc. The specific implementation is shown in fig. 2, which will be described in detail later, and will not be described again here.

B. The UE determines whether congestion release information is monitored by determining whether the UE moves to a new SGSN or a new MME in the core network.

In the embodiment of the present invention, if the UE moves to a new SGSN or MME in the core network, and the new SGSN or MME is not in the SM congestion state or the MM congestion state, it indicates that congestion release information is monitored. The UE may normally initiate an SM request or an MM request at this time. The specific implementation is shown in fig. 3, which will be described in detail later, and will not be described again here.

C. And monitoring the information of the SM congestion relief based on the APN through an MM flow or an SM flow or a paging flow or a Notification flow initiated by a core network, or monitoring the information of the SM congestion relief based on the APN through an MM flow initiated by UE.

The specific implementation is shown in fig. 4, which will be described in detail later, and will not be described again here.

D. And the SM flow or the called service flow or the paging flow initiated by the core network or the information of the congestion relief of the general NAS-level MM is monitored.

The specific implementation is shown in fig. 5, which will be described in detail later, and will not be described again here.

5. And if the congestion relief information is monitored, the UE stops the back-off timer.

In the embodiment of the present invention, the back-off timer is stopped when the UE monitors the SM congestion or MM congestion release information. The disabled SM or MM flow is resumed.

In the embodiment of the invention, the UE monitors the information of SM congestion or MM congestion relief during the running period of the back-off timer, so that the UE can timely acquire the information of network congestion relief.

Example two:

fig. 2 is a flowchart of a congestion control method according to a second embodiment of the present invention, and for convenience of description, only the parts related to the embodiment of the present invention are shown.

The UE initiates an SM request or MM request to the core network.

And 4, the UE runs a back-off timer according to the back-off time.

In the embodiment of the present invention, if the core network returns a message rejecting the MM request, the reject message does not allocate an RAI or a TAI list (multiple TAIs) to the UE, and the UE shall store the current RAI or TAI by itself. When the UE runs the back-off timer, the UE prohibits the SM or MM flow initiated by the UE, but does not prohibit the SM or MM flow initiated by the network.

5. When a preset condition is satisfied, the UE attempts to initiate an SM request or an MM request.

Although the UE prohibits the SM or MM procedure initiated by the UE, when the preset condition is satisfied, if the SM request or MM request initiated by the UE can be attempted to be accepted by the SGSN or MME, it indicates that the SGSN or MME has released the SM congestion or MM congestion; if the SM request or MM request initiated by the UE is not accepted by the SGSN or MME, the SM congestion or MM congestion is not released by the SGSN or MME. Wherein the preset condition comprises at least one of the following conditions: the running time of the back-off timer reaches a preset threshold, or the UE detects a new RAI, or the UE detects a new TAI, or the UE has a requirement for initiating an SM flow. The preset thresholds include, but are not limited to: one quarter over time, one half over time, three quarters over time, etc.

6. The core network returns a message accepting the SM request or MM request.

In the embodiment of the present invention, if the core network accepts the SM request or the MM request, it indicates that the core network has released the SM congestion or the MM congestion, that is, the UE monitors the congestion release information.

The UE stops the back-off timer.

In the embodiment of the invention, the UE stops the back-off timer to indicate that the congestion is relieved, and the forbidden SM or MM flows are recovered.

In the embodiment of the present invention, if the SM request or MM request initiated by the UE is not accepted by the core network, it indicates that the core network has not released the SM congestion or MM congestion, and tries to initiate the SM request or MM request again after waiting for the preset condition to be met next time.

In the embodiment of the invention, the UE tries to initiate the SM request or the MM request under the preset condition, so that the UE can timely acquire the information that the network congestion is relieved.

Example three:

fig. 3 is a flowchart of a congestion control method according to a third embodiment of the present invention, and for convenience of description, only the parts related to the embodiment of the present invention are shown.

In the embodiment of the present invention, the core network includes a plurality of SGSNs or MMEs, and the UE is moved from a first SGSN/MME to a second SGSN/MME.

1. The first SGSN/MME determines that SM congestion or MM congestion has occurred.

The UE initiates an SM request or an MM request to the first SGSN/MME.

3. The first SGSN/MME rejects the SM request or MM request initiated by the UE and returns the back-off time and RAI list or TAI list.

In the embodiment of the present invention, the RAI list indicates a service area of an SGSN, and the TAI list indicates a service area of an MME.

And 4, the UE stores the RAI list or the TAI list and runs a back-off timer according to the back-off time.

In the embodiment of the invention, since the UE already knows that the first SGSN/MME is in a congestion state, SM or MM flow is prohibited.

5. When the UE moves to an RA (Routing Area) outside the RAI list or when the UE moves to a TA (Tracking Area) outside the TAI list, the RAI list or the TAI list is deleted and the back-off timer is stopped.

In the embodiment of the invention, whether the UE moves to a new SGSN or a new MME is judged by judging whether the UE moves to an RA outside an RAI list or whether the UE moves to a TA outside a TAI list. When the UE moves to an RA outside an RAI list or moves to a TA outside a TAI list during the operation period of the back-off timer, the UE is considered to have moved to a new SGSN or a new MME, and the UE defaults that the new SGSN or the new MME is not congested, so the UE judges that the information of congestion relief is monitored when the RA outside the RAI list or the UE moves to the TA outside the TAI list. The UE stops the back-off timer and resumes the SM or MM flow, i.e. the UE may initiate the SM or MM flow to the new SGSN or MME.

The UE initiates an SM request or an MM request to the second SGSN/MME.

7. The second SGSN/MME accepts the SM request or MM request initiated by the UE.

In the embodiment of the invention, if the second SGSN/MME to which the UE moves is not in the SM congestion state or the MM congestion state, the SM request or the MM request sent by the UE can be processed normally. And if the second SGSN/MME to which the UE moves is in the SM congestion state or the MM congestion state, executing the step 8.

8. And the second SGSN/MME rejects the SM request or the MM request initiated by the UE and returns new back-off time and an RAI list/TAI list.

In the embodiment of the invention, if the second SGSN/MME to which the UE moves is in an SM congestion state or an MM congestion state, the SM request or MM request sent by the UE is rejected, and new back-off time and a new RAI list or TAI list are returned.

And 9, the UE runs a new back-off timer according to the new back-off time and stores a new RAI list/TAI list.

In the embodiment of the invention, the UE can sense the movement to a new SGSN or MME and think that the congestion relief information is monitored by judging whether the UE moves to an RA outside an RAI list or whether the UE moves to a TA outside a TAI list.

Example four:

fig. 4 is a flowchart of a congestion control method according to a fourth embodiment of the present invention, and for convenience of description, only the parts related to the embodiment of the present invention are shown. At this point the core network has APN based SM congestion.

1. The core network determines that APN-based SM congestion has occurred.

And 2, the UE initiates an SM request to the core network.

3. The core network rejects the SM request initiated by the UE and returns the back-off time.

And 4, the UE runs a back-off timer according to the back-off time.

In the embodiment of the invention, because the SM congestion based on the APN occurs, the SM flow is forbidden, and the MM flow can be normally carried out.

5. The core network determines that APN based SM congestion has been relieved.

6. The core network initiates an MM flow or an SM flow or a paging flow or a Notification flow to notify the UE that the congestion is relieved, or the core network notifies the UE that the congestion is relieved through the MM flow initiated by the UE.

In the embodiment of the present invention, the MM procedure initiated by the UE includes, but is not limited to, a Routing Area Update (RAU) or a Tracking Area Update (TAU) or a periodic RAU or TAU procedure.

In the embodiment of the present invention, for the UE, the information of APN-based SM congestion relief includes, but is not limited to: the UE detects an SM flow, a paging flow, or a Notification flow initiated by a core network, or the UE receives a back-off timer stopping indication or a congestion relieving indication through an RAU or TAU, a periodic RAU or a periodic TAU, or an MM flow initiated by the UE.

If the UE moves to a new SGSN or a new MME and the new SGSN or the new MME is not congested, the new SGSN or the new MME may know from the old SGSN or MME that the UE is running the back-off timer, and the new SGSN or the new MME should replace the old SGSN or MME to notify the UE that the APN-based SM congestion has been released.

The UE stops the back-off timer.

In the embodiment of the invention, the UE recovers the forbidden SM flow after stopping the back-off timer.

In the embodiment of the invention, the SGSN/MME actively informs the UE after releasing the congestion, so that the UE can timely acquire the information that the network congestion is released.

Example five:

fig. 5 is a flowchart of a congestion control method according to a fifth embodiment of the present invention, and for convenience of description, only the parts related to the embodiment of the present invention are shown. In this embodiment, the core network has a generic NAS level MM congestion and the UE is already in the attached state.

1. The core network determines that generic NAS level MM congestion has occurred.

The UE initiates an MM request to the core network.

3. The core network rejects the MM request initiated by the UE and returns the back-off time.

And 4, the UE runs a back-off timer according to the back-off time, reserves the RAU or TAU triggered by moving to the new RAI or TAI, and forbids other MM flows.

5. When the UE moves to a new RA or TA, the RAU or TAU is initiated.

In the embodiment of the invention, when the UE moves to a new RA or TA, the RAU or TAU is initiated, and at the moment, the SGSN or MME can know and store the latest position information of the UE according to the RAU or TAU initiated by the UE. For a RAU or TAU request by the UE, the core network returns a message denying the RAU or TAU.

6. The core network determines that generic NAS level MM congestion has been relieved.

7. The core network informs the UE that the congestion has been relieved.

In the embodiment of the present invention, after determining that the MM congestion of the generic NAS level is released, the core network notifies the UE that the congestion is released through an MM flow, an SM flow, a called service flow, or a paging flow initiated by the network according to the stored latest location information of the UE, where the congestion release information may be a back-off timer stop indication or a congestion release indication carried by the flow itself or a message in the flow.

In the embodiment of the present invention, the step of the core network notifying the UE that the congestion is relieved may also be: when UE moves to a new routing area RA or a new tracking area TA, the UE initiates an RAU request or a TAU request, and if the UE receives a message sent by the core network and accepting the request, the UE judges that the congestion relief information is monitored.

The UE stops the back-off timer.

In the embodiment of the invention, the UE stops the back-off timer and recovers the forbidden SM and MM flows.

If the UE moves to a new SGSN/MME, the UE detects that the UE moves to a new RAI/TAI and initiates an RAU/TAU procedure, and if the new SGSN/MME is not congested, the UE accepts the RAU/TAU request, which is also information that the generic NAS level MM congestion is released for the UE.

In the embodiment of the invention, when the SGSN/MME generates the MM congestion of the general NAS level, the RAU or TAU flow is reserved for the UE, so that the network can conveniently acquire the latest position information of the UE, and the information that the MM congestion of the general NAS level is relieved can be timely notified to the UE.

Example six:

when the core network is congested by the general NAS MM and the UE is in the attached state, the UE cannot perform the periodic RAU/TAU without stopping the back-off timer. Therefore, when the MM back-off time is greater than the sum of the interval of the periodic RAU/TAU and the time of the implicit detach, the core network may perform the implicit detach operation during the back-off timer running. Fig. 6 shows a flow of a method for solving this problem, and for convenience of explanation, only the part related to the embodiment of the present invention is shown.

In an embodiment of the invention, the core network comprises one or more SGSNs and/or MMEs.

The UE initiates an MM request to the core network.

And 4, the UE runs a back-off timer according to the back-off time.

5. The core network adjusts the sum of the mobile reachable timer MRT time and the implicit detach time so that the back-off time is less than the sum of the mobile reachable timer MRT time and the implicit detach time.

In the embodiment of the invention, when the back-off time is greater than the sum of the MRT time and the time of implicit detachment, the core network increases the MRT time or the time of implicit detachment to enable the back-off time to be smaller than the sum of the MRT time and the time of implicit detachment. Wherein the MRT time comprises: when the MRT is in operation, the MRT time is the residual operation time; when the MRT has stopped, the implicit detach timer is running, the MRT time is 0. Implicit detach times include: when the implicit detach timer is not running, the time is the set running time; when the implicit detach timer is running, this time is the remaining run time.

And 6, after the back-off timer operated by the UE is timed out, recovering the forbidden MM flow.

The time that the UE periodically performs RAU or TAU.

The UE initiates a request for periodic RAUs or TAUs to the core network.

9. The core network resets the MRT and reruns the MRT.

10. If the congestion is relieved, the core network receives a periodic RAU or TAU request initiated by the UE; otherwise, rejecting the request of the UE.

In the embodiment of the invention, the core network is prevented from executing the implicit detachment operation during the running period of the back-off timer by adjusting the MRT time and the implicit detachment time.

Example seven:

fig. 7 is a schematic structural diagram of a ue according to an embodiment of the present invention, and only shows a part related to the embodiment of the present invention for convenience of description. Wherein the user equipment comprises:

a request initiating unit 71, configured to initiate an SM request or an MM request to a core network.

A message receiving unit 72, configured to receive a message initiated by the core network to reject or accept the SM request or the MM request.

In the embodiment of the present invention, if the core network is not in the SM congested state or the MM congested state, the message receiving unit 72 receives a message initiated by the core network to accept an SM request or an MM request; if the core network is in the SM congested or MM congested state, the message receiving unit 72 receives a rejection message including a back-off time sent by the core network.

In the embodiment of the present invention, SM congestion or MM congestion includes, but is not limited to: APN based SM congestion, or APN based MM congestion, or generic NAS level MM congestion.

And a congestion monitoring unit 73, configured to run a back-off timer according to the back-off time, and monitor information of congestion relief during the running of the back-off timer.

In the embodiment of the present invention, since the congestion monitoring unit 73 monitors congestion relief information in different methods, the congestion monitoring unit 73 at least includes one of the following modules, namely, a condition monitoring module 731, an SGSN/MME moving module 732, a first flow monitoring module 733, a second flow monitoring module 734, and a third flow monitoring module 735. Wherein:

a condition monitoring module 731, configured to initiate an SM request or an MM request to a core network when a preset condition is met, and determine to monitor information of releasing congestion if a message for accepting the SM request or the MM request sent by the core network is received, where the preset condition includes that a back-off timer running time reaches a preset threshold and/or a user equipment detects a new RAI or a new TAI and/or a UE has a need to initiate an SM or MM procedure. The preset threshold includes, but is not limited to, one quarter of the time, one half of the time, three quarters of the time, and the like.

An SGSN/MME moving module 732, configured to determine that congestion relief information is monitored when the ue moves to a new SGSN or a new MME in the core network.

The first flow monitoring module 733 is configured to monitor, through an MM flow or an SM flow or a paging flow initiated by a core network or a Notification flow, information of SM congestion relief based on an APN, or monitor, through an RAU or a TAU or a periodic RAU or a periodic TAU, information of SM congestion relief based on an APN.

The second flow monitoring module 734 is configured to initiate an SM flow or a called service flow or a paging flow through the core network to monitor the information of the congestion relief of the generic NAS level MM.

The third flow monitoring module 735 is configured to, when the ue moves to a new routing area RA or tracking area TA and the ue initiates a routing area update RAU request or tracking area update TAU request, determine to monitor the congestion relief information if a message sent by the core network to accept the RAU request or the TAU request is received.

A back-off stopping unit 74, configured to stop the back-off timer if the congestion monitoring unit monitors the congestion relief information.

Example eight:

fig. 8 is a schematic structural diagram of an apparatus according to an eighth embodiment of the present invention, and only the portions related to the embodiment of the present invention are shown for convenience of explanation. The device can be a software unit, a hardware unit or a unit combining software and hardware which is built in the core network, or can be integrated into the core network or an application system of the core network as an independent pendant. Wherein:

a congestion judging unit 81, configured to determine whether or not a generic non-access stratum NAS level MM congestion occurs.

A request receiving unit 82, configured to, when the congestion determining unit determines that the MM congestion of the generic NAS level occurs, receive an MM request sent by a user equipment UE, and then return a rejection message to the UE, where the rejection message carries a backoff time.

And a time keeping unit 83, configured to, when the backoff time is greater than the sum of the MRT time of the mobile reachable timer and the implicit detach time, adjust the MRT time and/or the implicit detach time so that the backoff time is less than the sum of the MRT time and the implicit detach time.

In the embodiment of the invention, the core network keeps the back-off time smaller than the sum of the MRT time and the implicit detach time by reducing the MRT time or the implicit detach time.

In the embodiment of the invention, the core network is prevented from executing the implicit detachment operation during the running period of the back-off timer by adjusting the MRT time and the implicit detachment time. It will be understood by those skilled in the art that all or part of the steps in the method for implementing the above embodiments may be implemented by relevant hardware instructed by a program, and the program may be stored in a computer readable storage medium, such as ROM/RAM, magnetic disk, optical disk, etc.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A method of congestion control, the method comprising:

user equipment UE initiates a first session management SM request or a first mobility management MM request to a core network;

the UE receives a rejection message which is sent by the core network due to SM congestion or MM congestion and contains a back-off time;

the UE runs a back-off timer according to the back-off time, monitors information of congestion relief during the running period of the back-off timer, and stops the back-off timer if the information of congestion relief is monitored;

the information to listen for congestion relief during the back-off timer running comprises:

when a preset condition is met, the UE initiates a second SM request or a second MM request to the core network;

if the UE receives a message sent by the core network and used for accepting the second SM request or the second MM request, judging that the congestion relief information is monitored;

or,

when the UE moves to a routing area RA outside a routing area identifier RAI list or moves to a tracking area TA outside a tracking area identifier TAI list, judging that congestion relief information is monitored; the reject message further includes the RAI list representing a service area of an SGSN or the TAI list representing a service area of an MME;

or,

when the core network is SM congestion based on Access Point Name (APN), the information for monitoring congestion relief during the operation of the back-off timer comprises:

the UE monitors information of SM congestion relief based on APN through a routing area update RAU or a tracking area update TAU or a periodic RAU or a periodic TAU;

or,

when the core network is congested with a generic non-access stratum (NAS) level MM, the information for monitoring congestion relief during the operation of the back-off timer comprises:

when the UE moves to a new routing area RA or a new tracking area TA, the UE initiates a routing area update RAU request or a tracking area update TAU request, and if the UE receives a message sent by the core network and accepting the RAU request or the TAU request, the UE judges that the congestion relief information is monitored;

after the UE receives a rejection message containing a back-off time issued by a core network due to SM congestion or MM congestion, the method further includes:

2. The method of claim 1, wherein the preset condition comprises at least one of:

the running time of the back-off timer reaches a preset threshold; or

The UE detects a new Routing Area Identifier (RAI); or

The UE detects a new tracking area identity, TAI.

3. The method according to claim 1 or 2, wherein the core network comprises one or more serving general packet radio service technology support nodes, SGSN, and/or a mobility management entity, MME.

4. A user equipment, the user equipment comprising:

a request initiating unit, configured to initiate a first session management SM request or a first mobility management MM request to a core network;

a back-off stopping unit, configured to stop the back-off timer if the congestion monitoring unit monitors the congestion relief information; the congestion monitoring unit at least comprises any one of the following:

a condition monitoring module, configured to initiate a second SM request or a second MM request to the core network when a preset condition is met, and determine to monitor congestion relief information if a message that is sent by the core network and accepts the second SM request or the second MM request is received, where the preset condition includes that a running time of a back-off timer reaches a preset threshold and/or a new routing area identity RAI or a new tracking area identity TAI is detected;

a first flow monitoring module, configured to monitor information of SM congestion relief based on APN through a routing area update RAU or a tracking area update TAU or a periodic RAU or a periodic TAU;

a third flow monitoring module, configured to determine that congestion relief information is monitored if a message sent by the core network to accept a Routing Area Update (RAU) request or a Tracking Area Update (TAU) request is received when the ue moves to a new RA or TA and the ue initiates the RAU or TAU request;

the user equipment further comprises:

a storing unit, configured to store a current routing area identifier RAI or a current tracking area identifier TAI, or a TAI list included in the reject message.