CN105764042B

CN105764042B - A kind of methods, devices and systems of processing home subscriber server registration storm

Info

Publication number: CN105764042B
Application number: CN201410784162.9A
Authority: CN
Inventors: 于青; 宋月; 姜怡
Original assignee: China Mobile Communications Group Co Ltd
Current assignee: China Mobile Communications Group Co Ltd
Priority date: 2014-12-16
Filing date: 2014-12-16
Publication date: 2019-03-26
Anticipated expiration: 2034-12-16
Also published as: CN105764042A

Abstract

The invention discloses a kind of methods of processing home subscriber server (HSS) registration storm, HSS is determined when having the risk that registration storm occurs, it is preferential long term evolution voice (VoLTE) or prioritized data according to carrier policy, corresponding network edge network element is notified to execute registration limitation；The present invention also discloses a kind of device and system of processing HSS registration storm.

Description

Method, device and system for processing registration storm of home subscriber server

Technical Field

The present invention relates to telecommunications network technologies, and in particular, to a method, an apparatus, and a system for handling a Home Subscriber Server (HSS) registration storm.

Background

With the commercial deployment of voice over long term evolution (VoLTE), the HSS is used as a core entity for centrally managing user data and service data of a telecommunication network, and has interactive operation with different functional domains such as an Evolved Packet Core (EPC), an IP Multimedia Subsystem (IMS), a service platform, and so on, and how to ensure the availability thereof is more and more important.

The HSS is mainly used to store user data and service data, and the user data needs to be read from the HSS for authentication and authorization both in EPC registration and in IMS registration. Meanwhile, the application server may also need the HSS to cooperate with the HSS to store and read the service data.

When a wireless side network element (evolved node (eNode)), an EPC network element (mobile management entity (MME), a Serving Gateway (SGW), a packet data gateway (PGW), etc.) fails, whether the network element is restarted or performs function switching or load redistribution through disaster tolerance and load balancing mechanisms such as 1+1 backup or Pool group (Pool), etc., an original online user may initiate EPC and IMS registration again, and both registration flows may cause an increase in HSS load. Especially, if the redundancy or disaster recovery mechanism of the network planning is not ideal, when the subsequent disaster recovery mechanism of the failed network element still cannot handle the processing of a large number of re-registrations, it may cause the cycle of short-time high-frequency re-registrations, which causes a serious impact to the EPC network element, that is, a so-called "registration storm", and the HSS is the network element most vulnerable to the impact.

At present, the problem of solving the registration storm is mainly focused on the IMS field, including the following ways:

1) and setting a longer IMS registration period, namely when a user initiates IMS registration, the network side specifies the re-registration period of the IMS terminal through an aging (expire) parameter.

The advantages are that: when the registration storm occurs, the registration flow rate is attenuated more quickly, and the situation that a registered user occupies more resources too quickly is avoided;

the disadvantages are as follows:

(1) the network side cannot synchronize the information whether the terminal is on line or not in time;

(2) the problem that after the wireless or EPC equipment is recovered due to failure, all original users can serve as new users to initiate initial registration at the same time cannot be solved;

(3) the registration pressure of IMS to HSS can be relieved only, and the EPC aspect is not involved.

2) Safety protection is performed through IMS border network elements, such as a Session Border Controller (SBC), an interrogating call session control function (I-CSCF, interworking CSCF), a service session control (S-CSCF), and the like, that is, when a registration storm occurs, the SBC intelligently discards an incoming registration request by detecting its CPU load to a set threshold, and disperses the request to a longer time window through a retransmission mechanism, and such processing may be based on statistics or for each terminal.

The advantages are that: the overload source is directly judged and controlled at the IMS boundary, so that the registration pressure of the IMS to the HSS can be effectively controlled;

the disadvantages are as follows:

(1) the occurrence of a registration storm cannot be accurately judged, the overload of a local SBC is not necessarily caused by the registration storm, and also is not necessarily caused by 'fatal' pressure (possibly, the service usage amount is increased) on an HSS, and when the registration storm occurs, the sum of the registration loads from a plurality of non-overloaded SBCs is likely to generate excessive impact on the HSS together theoretically;

(2) the registration pressure of IMS to HSS can be relieved only, and the EPC aspect is not involved.

3) The signaling source is limited by HSS, that is, HSS monitors the incoming Diameter (Diameter) request rate of each peer network element, such as MME, Call Session Control Function (CSCF), Telephone Application Server (TAS) and the like, if the incoming Diameter (Diameter) request rate exceeds the preset upper limit, HSS sends an alarm to a network element network management system, the alarm indicates the peer network elements exceeding the preset threshold, including IP address and port number, HSS starts the Diameter peer lock and forbids the peer network element request.

The advantages are that: the pressure of the HSS can be accurately judged, and the condition of whole-network paralysis can be effectively organized;

the disadvantages are as follows:

(1) the execution point is at the HSS, and the rejected request brings unnecessary load to the network element before the HSS;

(2) the mode is a 'final' processing method of the HSS and is also a necessary mechanism, but the mode is carried out only based on the HSS load, the priority strategy between EPC registration and VoLTE registration cannot be distinguished, and registration storm can not be avoided in advance by optimizing the ratio between different requests.

To sum up, the current solutions for registration storm mainly fall into two categories, one is to judge and constrain the IMS registration request at the edge of the IMS network, and the other is to judge and constrain the requests of each party at the HSS. Either not ideal at the decision point or not ideal at the processing point and there is no way to balance between EPC and IMS according to operator policy.

Disclosure of Invention

In order to solve the existing technical problems, the invention mainly provides a method, a device and a system for processing HSS registration storm.

The technical scheme of the invention is realized as follows:

the invention provides a method for processing HSS registration storm, which comprises the following steps:

and when determining that the risk of registration storm occurs, the HSS informs a corresponding network edge network element to execute registration limitation according to whether the operator strategy is priority long-term evolution voice over LTE (voice over long term evolution) or priority data.

In the foregoing solution, the network edge network element includes: a mobile management entity MME, a proxy call session control function/session border controller P-CSCF/SBC.

In the foregoing solution, the determining, by the HSS, that there is a risk of a registration storm includes: the HSS monitors incoming Diameter messages on the first interface and the second interface, determines the registration request intensity on the first interface and the second interface according to the incoming Diameter messages on the first interface and the second interface, and determines that the risk of registration storm occurs when the registration request intensity on the first interface and the second interface both exceed corresponding intensity thresholds and the HSS real-time load exceeds a registration storm judgment threshold.

In the foregoing solution, the determining, by the HSS, that there is a risk of a registration storm includes: configuring an overload threshold of an HSS as A%, a registration storm judgment threshold of the HSS as B%, a registration storm risk relief judgment threshold as C%, C < B < A, a real-time load of the current HSS as m%, a strength threshold of an S6a interface as S _ EPC, and a strength threshold of a Cx interface as S _ IMS;

the HSS calculates the registration request strength n _ EPC on the S6a interface and the registration request strength p _ IMS on the Cx interface from within the same area D, and determines that there is a risk of a registration storm occurring when m > B and n _ EPC > S _ EPC and p _ IMS > S _ IMS.

In the foregoing solution, the notifying, according to whether the operator policy is priority VoLTE or priority data, a corresponding network edge network element to execute registration restriction includes:

if the operator strategy is to ensure that a user successfully registering the EPC uses the VoLTE service, the HSS sends a notification message for controlling the EPC registration success rate of the evolved packet core network to the MME, wherein the notification message carries the percentage for reducing the registration request intensity;

and if the operator strategy is to ensure that more users establish data connection, the HSS sends a notification message for controlling the registration success rate of the IP multimedia subsystem IMS to the P-CSCF/SBC in the area D, wherein the notification message carries the percentage for reducing the registration request intensity.

In the above scheme, the method further comprises: the HSS determines the standard of releasing the risk of the registration storm to be as follows: m < C and n _ EPC < S _ EPC and p _ IMS < S _ IMS; and when the HSS determines that the risk is relieved, the MME or the P-CSCF/SBC is informed to relieve the registration limitation.

The present invention provides an HSS, comprising: a risk determination module and a notification module; wherein,

the risk determining module is used for determining that the risk of registration storm occurs and triggering the notification module;

and the notification module is used for notifying the corresponding network edge network element to execute registration limitation according to whether the operator strategy is priority VoLTE or priority data.

In the above scheme, the risk determining module is specifically configured to monitor incoming Diameter messages on the first interface and the second interface, determine registration request strengths on the first interface and the second interface according to the incoming Diameter messages on the first interface and the second interface, and determine that a risk of a registration storm occurs when the registration request strengths on the first interface and the second interface both exceed corresponding strength thresholds and when an HSS real-time load exceeds a registration storm decision threshold.

In the above scheme, the risk determining module is specifically configured to pre-configure an overload threshold of the HSS as a%, a registration storm decision threshold of the HSS as B%, a registration storm risk release decision threshold as C%, C < B < a, a real-time load of the current HSS is m%, a strength threshold of an S6a interface is S _ EPC, and a strength threshold of a Cx interface is S _ IMS; the registration request strength n _ EPC on the S6a interface and the registration request strength p _ IMS on the Cx interface from within the same area D are calculated, and when m > B and n _ EPC > S _ EPC and p _ IMS > S _ IMS, it is determined that there is a risk of a registration storm.

In the above scheme, the notification module is specifically configured to send a notification message for controlling an EPC registration success rate to an MME if an operator policy is that a user who has successfully EPC-registered uses a VoLTE service, where the notification message carries a percentage that reduces registration request intensity;

and if the operator strategy is to ensure that more users establish data connection, sending a notification message for controlling the success rate of IMS registration to the P-CSCF/SBC in the area D, wherein the notification message carries the percentage for reducing the intensity of the registration request.

In the foregoing solution, the notification module 32 is further configured to, according to the criterion for determining cancellation of risk of registered storm: m < C and n _ EPC < S _ EPC and P _ IMS < S _ IMS, and after determining risk release, the MME or the P-CSCF/SBC is informed to release the registration restriction.

The invention provides a system for processing HSS registration storm, which comprises: HSS, network edge network element; wherein,

the HSS is used for informing the corresponding network edge network element to execute registration limitation according to whether the operator strategy is priority VoLTE or priority data when the risk of registration storm is determined;

and the network edge network element is used for executing registration limitation according to the notice of the HSS.

In the above scheme, the network edge network element includes an MME and a P-CSCF/SBC.

The invention provides a method, a device and a system for processing HSS registration storm.A HSS informs a corresponding network edge network element to execute registration limitation according to whether an operator strategy is priority VoLTE or priority data when determining that the risk of registration storm occurs; therefore, whether the VoLTE or the data is guaranteed preferentially can be determined according to the operator strategy, the execution point is located at the network edge network element, and unnecessary load brought to the network element before the HSS by the rejected request is reduced to the maximum extent.

Drawings

Fig. 1 is a flowchart illustrating a method for handling an HSS registration storm according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a network architecture according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of an HSS according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a system for handling an HSS registration storm according to an embodiment of the present invention.

Detailed Description

In the embodiment of the present invention, when the HSS determines that there is a risk of a registration storm, the HSS notifies a corresponding network edge network element to execute registration restriction according to whether an operator policy is priority VoLTE or priority data, where the network edge network element includes: MME and P-CSCF/SBC.

The invention is further described in detail below with reference to the figures and the specific embodiments.

The embodiment of the invention realizes a method for processing HSS registration storm, as shown in figure 1, the method comprises the following steps:

step 101: the HSS determines that the risk of registration storm occurs;

specifically, the HSS monitors incoming Diameter messages on a first interface and a second interface, determines the registration request intensity on the first interface and the second interface according to the incoming Diameter messages on the first interface and the second interface, and determines that the risk of registration storm occurs when the registration request intensity on the first interface and the second interface both exceed corresponding intensity thresholds and the HSS real-time load exceeds a registration storm judgment threshold; wherein the first interface is an interface for monitoring MME, such as S6 a; the second interface is an interface for monitoring the P-CSCF/SBC, such as Cx.

Taking the network architecture shown in fig. 2 as an example, the HSS determines that there is a risk of a registration storm as follows:

presetting an overload threshold of an HSS (namely, once the overload threshold is exceeded, an HSS overload protection mechanism is triggered) as A%, a registration storm judgment threshold of the HSS as B%, a registration storm risk relief judgment threshold as C%, C < B < A, the real-time load of the current HSS as m%, the strength threshold of an S6a interface as S _ EPC, and the strength threshold of a Cx interface as S _ IMS;

the HSS calculates the registration request intensity n _ EPC on an S6a interface and the registration request intensity p _ IMS on a Cx interface from the same area D, and when m > B and n _ EPC > S _ EPC and p _ IMS > S _ IMS, the risk of registration storm is determined;

the registration request strength on the S6a interface is obtained by calculating the number of EPC new registration requests in unit time, and the registration request strength on the Cx interface is obtained by calculating the number of IMS new registration requests in unit time;

the number of EPC new registration requests in the unit time may be calculated by a total number of registration requests in a period of time on the S6a interface, and the total number of registration requests in a period of time on the S6a interface may be calculated by one of the following two methods:

one is the sum of the number of all Location Update (LUR) requests on the S6a interface over a period of time;

secondly, subtracting the sum of the average number of the LURs in the ordinary time period from the sum of all the numbers of the LURs on the S6a interface in a period of time, wherein the period of time can be set according to a specific application environment, such as between 8 and 9 points per day or between 7 and 9 points per day;

the number of IMS new registration requests per unit time may be calculated from a total number of registration requests on a Cx interface in a period of time, and the total number of registration requests on the Cx interface in the period of time may be calculated in one of the following two manners:

first, the sum of the number of all User Authentication Requests (UARs) on the Cx interface over a period of time;

secondly, subtracting the sum of average UAR numbers in the period of time from the sum of all UAR numbers on the Cx interface in a period of time, wherein the period of time can be set according to specific application environments, such as 8-9 points per day or 7-9 points per day;

the method also comprises the following steps: the HSS determines that the registration request on the S6a interface and the registration request on the Cx interface are in the same area D, and the determining method is as follows:

the HSS acquires the geographical location information of the registration request on the S6a interface through the location information (such as CELL _ ID) transmitted in the LUR, acquires the geographical location information of the registration request on the Cx interface through an Attribute Value Pair (AVP) in a UAR message, wherein the AVP is transmitted to the HSS by an I-CSCF (serving call session control function), the I-CSCF acquires the geographical location information of the registration request on the Cx interface from PANI in a SIP (session initiation protocol) message sent by a P-CSCF/SBC, and transmits the geographical location information to the HSS through a designated AVP;

the HSS determines that the registration request on the S6a interface and the registration request on the Cx interface are in the same area D according to the fact that the two pieces of geographical position information are in the same area D;

the judgment criteria of the HSS for the registration storm are as follows: m > B and n _ EPC > S _ EPC and p _ IMS > S _ IMS.

Here, the A, B, C, S _ EPC and S _ IMS values are closely related to the networking architecture and user model, and are generally determined from empirical values and/or simulations.

Step 102: the HSS informs a corresponding network edge network element to execute registration limitation according to whether the operator strategy is priority VoLTE or priority data;

specifically, if the operator policy is to ensure that a user with successful EPC registration can use the VoLTE service, the HSS sends, to the MME, a notification message for controlling the EPC registration success rate, where the notification message may carry a percentage that reduces the registration request intensity, and if necessary, the percentage may be reduced by 30%, and the specific manner may be one of the following two manners:

as shown in fig. 2, the HSS reports the notification message to the operator network management system OSS through the same manufacturer equipment network management OMC, and issues the notification message to the MME through the MME and the same manufacturer equipment network management OMC;

or, sending the AVP appointed in the location update response (LUA) returned from any other HSS to the MME as the notification message to the MME;

if the operator policy is to ensure that more users establish data connection, the HSS sends a notification message for controlling the success rate of IMS registration to the P-CSCF/SBC in the area D, where the notification message may carry a percentage that reduces the intensity of the registration request, and if necessary, the percentage may be reduced by 30%, and the specific manner may be one of the following two manners:

as shown in fig. 2, the HSS reports the notification message to the operator network management system OSS through the equipment network management OMC of the same manufacturer, and issues the notification message to the P-CSCF/SBC through the equipment network management OMC of the same manufacturer;

or, the AVP appointed in the user authentication response (UAA) returned by any other HSS to the I-CSCF is taken as the notification message and sent to the I-CSCF, and the I-CSCF sends the notification message to the P-CSCF/SBC through the SIP header domain or body in the SIP response message for replying the P-CSCF/SBC.

Thus, after the MME and the P-CSCF/SBC receive the notification message of the registration limit sent by the HSS, the subsequent arrival registration request quantity is reduced by the notified percentage according to the notification message, and the limit degree can be controlled.

The method further comprises the following steps: the HSS determines the standard of releasing the risk of the registration storm to be as follows: m < C and n _ EPC < S _ EPC and p _ IMS < S _ IMS; after the HSS determines that the risk is removed, the MME or the P-CSCF/SBC is notified to remove the registration restriction through the notification message issuing mode, and the AVP value sent by the HSS to the MME or the P-CSCF/SBC can be set to be 0%.

In order to implement the above method, the present invention further provides an HSS, as shown in fig. 3, where the HSS includes: a risk determination module 31, a notification module 32; wherein,

a risk determining module 31, which may be implemented by an interface of the HSS in combination with a memory, and is configured to determine that there is a risk of a registration storm and trigger the notification module 32;

a notification module 32, which can be implemented by a processor of the HSS in combination with an interface, and is configured to notify a corresponding network edge network element to execute registration restriction according to whether an operator policy is VoLTE-first or data-first;

the risk determining module 31 is specifically configured to monitor incoming Diameter messages on the first interface and the second interface, determine registration request strengths on the first interface and the second interface according to the incoming Diameter messages on the first interface and the second interface, and determine that a risk of a registration storm occurs when the registration request strengths on the first interface and the second interface both exceed corresponding strength thresholds and an HSS real-time load exceeds a registration storm decision threshold; wherein the first interface is an interface for monitoring MME, such as S6 a; the second interface is an interface for monitoring the P-CSCF/SBC, such as Cx.

The risk determining module 31 is specifically configured to pre-configure an overload threshold of the HSS as a%, a registration storm decision threshold of the HSS as B%, a registration storm risk release decision threshold as C%, C < B < a, a real-time load of the current HSS is m%, a strength threshold of an S6a interface is S _ EPC, and a strength threshold of a Cx interface is S _ IMS; calculating the registration request intensity n _ EPC on an S6a interface and the registration request intensity p _ IMS on a Cx interface from the same area D, and determining that the risk of registration storm occurs when m is greater than B and n _ EPC is greater than S _ EPC and p _ IMS is greater than S _ IMS;

the method for determining that the registration request on the S6a interface and the registration request on the Cx interface are in the same area D includes:

acquiring geographical location information of a registration request on an S6a interface through location information (such as CELL _ ID) transferred in LUR, acquiring geographical location information of a registration request on a Cx interface through Attribute Value Pairs (AVP) in UAR message, wherein the AVP is transmitted to HSS by I-CSCF, the I-CSCF acquires geographical location information of the registration request on the Cx interface from PANI in SIP message sent by P-CSCF/SBC, and transfers the geographical location information to HSS through designated AVP;

and determining that the registration request on the S6a interface and the registration request on the Cx interface are in the same area D according to the fact that the two pieces of geographical location information are in the same area D.

The notification module 32 is specifically configured to send, to the MME, a notification message for controlling an EPC registration success rate if an operator policy is that it is ensured that a user with successful EPC registration can use a VoLTE service, where the notification message may carry a percentage that reduces the registration request intensity, and if necessary, the percentage may be reduced by 30%, and a specific manner may be one of the following two manners:

reporting the notification message to an operator network management system OSS through the OMC of the equipment of the same manufacturer, and issuing the notification message to an MME through the MME and the OMC of the equipment of the same manufacturer;

or, returning any other HSS to the designated AVP in the LUA of the MME as the notification message and sending the notification message to the MME;

if the operator policy is to ensure that more users establish data connection, sending a notification message for controlling the success rate of IMS registration to the P-CSCF/SBC in the area D, where the notification message may carry a percentage that reduces the intensity of the registration request, and if necessary, the percentage may be reduced by 30%, and the specific manner may be one of the following two manners:

reporting the notification message to an operator network management system OSS through the OMC of the equipment of the same manufacturer, and issuing the notification message to a P-CSCF/SBC through the P-CSCF/SBC and the OMC of the equipment of the same manufacturer;

The notification module 32 is further configured to, according to the criteria for determining release of risk of registered storm: and m < C, n _ EPC < S _ EPC and P _ IMS < S _ IMS, and after the risk is relieved, the MME or the P-CSCF/SBC is informed to relieve the registration restriction through the notification message issuing mode.

In order to implement the method, the present invention further provides a system for handling an HSS registration storm, as shown in fig. 4, the system includes: HSS 41, network edge network element 42; wherein,

the HSS 41 is configured to notify, when it is determined that there is a risk of a registration storm, a corresponding network edge network element 42 to execute registration restriction according to whether an operator policy is preferential VoLTE or preferential data;

a network edge network element 42 for performing registration restriction according to the notification of the HSS 41;

the network edge network element 42 comprises an MME 43 and a P-CSCF/SBC 44, wherein,

an MME 43 for performing registration restriction according to the notification of the HSS 41;

a P-CSCF/SBC 44 for performing registration restriction according to the notification of the HSS 41.

The structure of the HSS 41 is shown in fig. 3, and will not be described repeatedly here.

Here, the MME 43 is further configured to limit execution of the registration request according to a percentage carried in the notification message issued by the HSS 41, where the percentage reduces the strength of the registration request;

the P-CSCF/SBC 44 is further configured to limit execution of the registration request according to a percentage carried in the notification message issued by the HSS 41, where the percentage reduces the strength of the registration request.

In summary, the embodiment of the present invention can determine whether to preferentially guarantee VoLTE or data according to the operator policy, and the enforcement point is at the network edge network element, so as to reduce unnecessary load on the network element before the HSS caused by the rejected request to the maximum extent.

The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, and any modifications, equivalents, improvements, etc. that are within the spirit and principle of the present invention should be included in the present invention.

Claims

1. A method of handling a home subscriber server, HSS, registration storm, the method comprising:

2. The method of claim 1, wherein the network edge network element comprises: a mobile management entity MME and a proxy call session control function/session border controller P-CSCF/SBC.

3. The method of claim 2, wherein the HSS determining that there is a risk of a registration storm comprising: the HSS monitors incoming Diameter messages on the first interface and the second interface, determines the registration request intensity on the first interface and the second interface according to the incoming Diameter messages on the first interface and the second interface, and determines that the risk of registration storm occurs when the registration request intensity on the first interface and the second interface both exceed corresponding intensity thresholds and the HSS real-time load exceeds a registration storm judgment threshold.

4. The method of claim 2, wherein the HSS determining that there is a risk of a registration storm comprising: configuring an overload threshold of an HSS as A%, a registration storm judgment threshold of the HSS as B%, a registration storm risk relief judgment threshold as C%, C < B < A, a real-time load of the current HSS as m%, a strength threshold of an S6a interface as S _ EPC, and a strength threshold of a Cx interface as S _ IMS;

5. The method of claim 1, wherein notifying the corresponding network edge network element to perform registration restriction according to whether the operator policy is VoLTE-first or data-first comprises:

6. The method of claim 4, further comprising: the HSS determines the standard of releasing the risk of the registration storm to be as follows: m < C and n _ EPC < S _ EPC and p _ IMS < S _ IMS; and when the HSS determines that the risk is relieved, the MME or the P-CSCF/SBC is informed to relieve the registration limitation.

7. An HSS, comprising: a risk determination module and a notification module; wherein,

8. The HSS of claim 7, wherein the risk determination module is specifically configured to monitor incoming Diameter messages on the first interface and the second interface, determine registration request strengths on the first interface and the second interface according to the incoming Diameter messages on the first interface and the second interface, and determine that there is a risk of a registration storm occurring when the registration request strengths on the first interface and the second interface both exceed corresponding strength thresholds and the HSS real-time load exceeds a registration storm decision threshold.

9. The HSS of claim 8, wherein the risk determination module is specifically configured to pre-configure an overload threshold of the HSS as a%, a registration storm decision threshold of the HSS as B%, a registration storm risk resolution decision threshold as C%, C < B < a, a real-time load of the current HSS as m%, a strength threshold of an S6a interface as S _ EPC, and a strength threshold of a Cx interface as S _ IMS; the registration request strength n _ EPC on the S6a interface and the registration request strength p _ IMS on the Cx interface from within the same area D are calculated, and when m > B and n _ EPC > S _ EPC and p _ IMS > S _ IMS, it is determined that there is a risk of a registration storm.

10. The HSS of claim 7, wherein the notification module is specifically configured to send, to the MME, a notification message that controls the EPC registration success rate if the operator policy is to ensure that a user with successful EPC registration uses VoLTE service, where the notification message carries a percentage that reduces the registration request strength;

11. The HSS of claim 9, wherein the notification module 32 is further configured to, based on the criteria for determining release of registered storm risk: m < C and n _ EPC < S _ EPC and P _ IMS < S _ IMS, and after determining risk release, the MME or the P-CSCF/SBC is informed to release the registration restriction.

12. A system for handling HSS registered storms, the system comprising: HSS, network edge network element; wherein,

13. The system of claim 12, wherein the network edge network element comprises an MME and a P-CSCF/SBC.