WO2013060154A1

WO2013060154A1 - Method and device for updating pws key

Info

Publication number: WO2013060154A1
Application number: PCT/CN2012/077423
Authority: WO
Inventors: 李阳; 冯成燕
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-10-25
Filing date: 2012-06-25
Publication date: 2013-05-02
Also published as: CN103079197A

Abstract

Disclosed in the present invention are a method and device for updating Public Warning System (PWS) key。 According to the said method，when a preset condition is satisfied, UE receives updated PWS key from a network side device via a downlink NAS message; UE updates the current PWS key with the received PWS key. According to the technical solution provided by the present invention, the PWS security protection is enhanced by updating the PWS key in real time.

Description

TECHNICAL FIELD The present invention relates to the field of communications, and in particular to a method and apparatus for updating a public alert system (PWS) key. BACKGROUND OF THE INVENTION In order to enable users to receive timely, accurate and accurate alerts, warnings and critical information about disasters and other emergencies, the 3rd Generation Partnership Project (3GPP) defines the Public Alert System (PWS) service. . In the event of disasters such as earthquakes, tsunamis, hurricanes and wildfires, the business can enable the public to take appropriate action to protect themselves and their families from serious injury or death, or to suffer significant property damage.

Different communication networks defined by 3GPP, such as Global System of Mobile communication (GSM), Universal Mobile Telecommunications System (UMTS), and Long Term Evolution (LTE) Both support PWS services, and stipulate that the PWS service uses Cell Broadcast Service (CBS) to carry and transmit. The architecture is as shown in Figure 1. The functions of each network element are as follows: Cell Broadcast Entity (CBE): A communication network that is not defined by 3GPP. The CBE is responsible for formatting the Cell Broadcast Service (CBS), including dividing the CBS message into different pages. The Cell Broadcast Center (CBC) is a part of the core network and can be connected to multiple CBEs. The CBC is responsible for the management of CBS messages, including: determining the time when the CBS message starts broadcasting; determining the time when the CBS message stops broadcasting, and Instructing each BSC/RNC to stop broadcasting CBS messages; determining a time interval during which CBS messages are repeatedly broadcasted; determining a cell broadcast channel for broadcasting CBS messages, etc. For GSM networks, CBC and base station controllers located in the radio access network (Base The Station Controller (BSC) is connected; for the UMTS system, the CBC is connected to the Radio Network Controller (RNC) located in the radio access network through the Iu interface; for the LTE system, the CBC and the core The Mobility Management Entity (MME) is connected to the network. After receiving the alarm information sent by the CBE, the CBC configures and encapsulates it, and sends it to the BSC (GSM system) and RNC (UMTS system) of the affected area. MME (LTE system), BSC/RNC/MME forwards it to the base station (GSM system is BTS, UMTS) System is B, LTE systems e B) broadcast to the user. The currently defined CBS services are all sent on the broadcast channel. Currently, the broadcast channel does not have any security protection. An attacker can tamper with an alert message, or after receiving an alert message, replay in the same region or at another location at other times, causing unnecessary panic and confusion in the public. In order to prevent this from happening, 3GPP decided to secure the PWS by introducing a signature algorithm and a key management scheme by using a digital signature field and a timestamp. When the terminal receives the broadcasted alert message, it will first authenticate the message, and only if the authentication succeeds, it is considered to be a valid alert message. For any signature-based authentication scheme, the verifier needs to obtain the signer's key, which is usually a public key and needs to be guaranteed to be valid. That is, for the UE, it is necessary to obtain a signed key. At the same time, in order to ensure the freshness and security of the key, the key generally has an effective life cycle. During this life cycle, the key can be used normally. Before the key expires, the network needs to update the key and successfully enable the new key. In the current 3GPP specifications, there is also a lack of technical solutions for updating PWS keys. SUMMARY OF THE INVENTION The present invention provides a method and apparatus for updating a PWS key to at least solve the problem of the technical solution that the PWS key is not updated in the related art. According to an aspect of the present invention, a method of updating a PWS key is provided. The method for updating the PWS key according to the present invention includes: when the preset condition is met, the UE receives the updated PWS key sent by the network side device through the non-access stratum downlink message; the UE adopts the received PWS key. Updating current PWS key information, wherein the PWS key information includes a PWS key. In the above method, the PWS key information further includes an identifier of the PWS key. After the UE receives the updated PWS key information sent by the network side device from the non-access stratum downlink message, the method further includes: the UE saves the PWS secret. The ID of the key. In the above method, the preset condition includes one of the following: the predetermined duration is reached; the network side device receives the key update message sent by the cell broadcast center CBC, where the key update message includes: the updated PWS key and the PWS The identity of the key. In the above method, after the UE updates the current PWS key by using the received PWS key, the method further includes: the UE receiving the identifier of the updated PWS key sent by the network side device; and determining, by the UE, the saved PWS key Whether the identifier of the received updated PWS key is included in the identifier, if it is included, the update is successful. In the above method, the manner in which the network side device sends the identifier of the updated PWS key includes: a broadcast message delivery mode. In the above method, when the UE determines whether the identifier of the received PWS key includes the identifier of the received updated PWS key, the method further includes: if the identifier of the PWS key saved by the UE does not include the received update The identifier corresponding to the PWS key, the UE initiates a PWS key update procedure, and requests the updated PWS key to the network side device. In the above method, the UE initiates a PWS key update process, and the requesting the updated PWS key to the network side device includes: the UE sends a request message for updating the current PWS key to the network side device, where the request message carries the updated PWS The identifier of the key; the UE receives the updated PWS key delivered by the network side device. In the foregoing method, after the UE receives the identifier of the updated PWS key sent by the network side device, before the UE sends the request message for updating the current PWS key to the network side device, the method further includes: receiving, by the UE, The PWS message delivered by the network side device, where the PWS message is encrypted by using the updated PWS key. In the above method, when the UE uses the received PWS key to update the current PWS key to generate an abnormality, the method further includes: receiving, by the UE, a PWS message sent by the network side device, where the PWS message is an updated PWS key. The key is encrypted; the UE receives the identifier of the updated PWS key sent by the network side device; in the case that the UE fails to authenticate the PWS message by using the current PWS key, the UE sends the updated current PWS to the network side device. The request message of the key, wherein the request message carries an identifier of the updated PWS key; the UE receives the updated PWS key delivered by the network side device. In the above method, the non-access stratum downlink message includes: an advertisement message. According to another aspect of the present invention, a method of updating a PWS key is provided. The method for updating the PWS key according to the present invention includes: when the preset condition is met, the network side device is triggered to send the updated PWS key; and the network side device sends the updated PWS key to the UE by using the non-access stratum downlink message. So that the UE updates the current PWS key information with the received PWS key, wherein the PWS key information includes a PWS key. In the above method, the PWS key information further includes an identifier of the PWS key. After the UE receives the updated PWS key information sent by the network side device from the non-access stratum downlink message, the method further includes: the UE saves the PWS secret. The ID of the key. In the above method, the preset condition includes one of the following: the predetermined duration is reached; the network side device receives the key update message sent by the cell broadcast center CBC, where the key update message includes: the updated PWS key and the PWS The identity of the key. In the above method, after the UE updates the current PWS key by using the received PWS key, the method further includes: sending, by the network side device, an identifier of the updated PWS key. In the above method, the manner in which the network side device delivers the updated PWS key includes: a broadcast message delivery mode. In the foregoing method, after the identifier of the updated PWS key is sent by the network side device, the method further includes:

The updated PWS key sent by the network side device is not included in the identifier of the PWS key saved by the UE, and the UE initiates a PWS key update process, and requests the updated PWS key from the network side device. In the above method, the UE initiates a PWS key update procedure, and requesting the updated PWS key from the network side device includes: the network side device receives a request message for updating the current PWS key from the UE, where the request message carries an update. The identifier of the PWS key; the network side device delivers the updated PWS key. In the above method, after the network side device sends the identifier of the updated PWS key, before the network side device receives the request message for updating the current PWS key from the UE, the method further includes: sending, by the network side device, the PWS message Wherein, the PWS message is encrypted using the updated PWS key. In the above method, when the UE uses the received PWS key to update the current PWS key to be abnormal, the method further includes: the network side device sends a PWS message, where the PWS message is encrypted by using the updated PWS key; The network side device sends an identifier of the updated PWS key, where the UE fails to use the current PWS key to authenticate the PWS message, the network side device receives the request message for updating the current PWS key from the UE, where The request message carries an identifier of the updated PWS key; the network side device delivers the updated PWS key. In the above method, the non-access stratum downlink message includes: an advertisement message. According to still another aspect of the present invention, an apparatus for updating a PWS key is provided. The device for updating the PWS key according to the present invention includes: a first receiving module, configured to receive an updated PWS key sent by the network side device through the non-access stratum downlink message when the preset condition is met; And being configured to update current PWS key information by using the received PWS key, wherein the PWS key information includes a PWS key. In the above apparatus, the PWS key information further includes an identifier of the PWS key, and the apparatus further includes: a saving module, configured to save the identifier of the PWS key. In the above apparatus, the method further includes: a second receiving module, configured to receive an identifier of the updated PWS key sent by the network side device; and a determining module, configured to determine whether the identifier of the saved PWS key includes the received The identifier of the updated PWS key, if included, the update is successful. In the above apparatus, the method further includes: a sending module, configured to send, to the network side device, a request message for updating the current PWS key, when the output of the determining module is negative or the first receiving module or the updating module performs an operation abnormality, where The request message carries an identifier of the updated PWS key; the third receiving module is configured to receive the updated PWS key delivered by the network side device. In the above apparatus, the method further includes: a fourth receiving module, configured to receive a PWS message sent by the network side device, where the PWS message is encrypted by using an updated PWS key. According to still another aspect of the present invention, an apparatus for updating a PWS key is provided. The device for updating the PWS key according to the present invention includes: a triggering module, configured to trigger the network side device to send the updated PWS key when the preset condition is met; and the first sending module is configured to send the downlink message through the non-access stratum The updated PWS key is sent, so that the UE updates the current PWS key information by using the received PWS key, where the PWS key information includes a PWS key. In the above apparatus, the method further includes: a second sending module, configured to send the identifier of the updated PWS key. In the above apparatus, the method further includes: a fifth receiving module, configured to receive a request message for updating the current PWS key from the UE, where the request message carries the updated PWS key The third sending module is configured to deliver the updated PWS key. In the above apparatus, the method further includes: a fourth sending module, configured to send a PWS message, where the PWS message is encrypted by using the updated PWS key. With the present invention, the current PWS key is updated before the current PWS key usage period expires, and the new PWS key can be successfully enabled, which solves the technical solution that the PWS key is not updated in the related art. The problem, which in turn achieves the effectiveness of PWS security protection through real-time updates of PWS keys.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawing: 1 is a schematic diagram of a network architecture of a PWS in a 3GPP network according to the related art; FIG. 2 is a flowchart of a method for updating a PWS key according to a first embodiment of the present invention; FIG. 3 is a PWS key according to an example 1 of the present invention. FIG. 4 is a flowchart of a method for updating a PWS key according to Example 2 of the present invention; FIG. 5 is a flowchart of a method for updating a PWS key according to Example 3 of the present invention; FIG. 6 is a flowchart according to the present invention. FIG. 7 is a flowchart of a method for updating a PWS key according to Embodiment 2 of the present invention; FIG. 8 is a flowchart of an apparatus for updating a PWS key according to Embodiment 1 of the present invention; FIG. 9 is a block diagram showing a structure of an apparatus for updating a PWS key according to a preferred embodiment of the present invention; FIG. 10 is a block diagram showing a structure of an apparatus for updating a PWS key according to a second embodiment of the present invention; A block diagram of a device for updating a PWS key of a preferred embodiment 2 of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. 2 is a flow chart of a method for updating a PWS key according to a first embodiment of the present invention. As shown in FIG. 2, the method mainly includes the following processes: Step S202: When the preset condition is met, the UE receives the updated PWS key information sent by the network side device by using the non-access stratum downlink message, where The PWS key information includes a PWS key; Step S204: The UE updates the current PWS key by using the received PWS key. In the related art, there is currently no method for how to update the PWS key. The method shown in FIG. 2 is adopted, and when the preset condition is met, the network side device receives the updated PWS key by using the updated PWS key delivered by the non-access stratum downlink message; and adopts the received PWS. The key updates the current PWS key, which solves the problem that the related art lacks the technical solution for updating the PWS key, and realizes the security protection of the PWS by real-time updating of the PWS key. Preferably, the PWS key information further includes an identifier of the PWS key, and after the UE receives the updated PWS key information sent by the network side device by using the non-access stratum downlink message, the method further includes: the UE saving the PWS key Logo. Preferably, the non-access stratum downlink message may include, but is not limited to: an announcement message. Preferably, the foregoing preset condition may include but is not limited to one of the following:

(1) reaching a predetermined duration; in a specific implementation process, the predetermined duration may be preset by using a timer or the like for the usage period of the PWS key;

(2) The network side device receives the key update message delivered by the cell broadcast center (CBC), where the key update message includes: the updated PWS key and the identifier of the PWS key. Preferably, after the UE updates the current PWS key by using the received PWS key, the following processing may also be included:

(1) The UE receives an identifier of the updated PWS key delivered by the network side device;

(2) The UE determines whether the identifier of the stored PWS key includes the identifier of the received updated PWS key, and if yes, the update succeeds. Preferably, the manner in which the network side device sends the updated PWS key may include, but is not limited to, a broadcast message sending manner. Preferably, when the UE determines whether the identifier of the saved PWS key includes the identifier of the updated PWS key, the following processing may be further included: if the PWS secret saved by the UE The identifier of the key does not include the identifier corresponding to the received PWS key, and the UE initiates a PWS key update procedure, and requests the network side device to update the PWS key. Preferably, the UE initiates a PWS key update procedure, and the requesting the updated PWS key to the network side device may include the following processing: (1) The UE sends a request message for updating the current PWS key to the network side device, where the request message carries The identifier of the updated PWS key; (2) The UE receives the updated PWS key delivered from the network side device. Through the above processing, the UE can accurately determine whether the update is successful. If the identifier of the updated PWS key is consistent with the identifier of the received updated PWS key, the update is successful; if the updated PWS key is identified and received If the identifiers of the updated PWS keys are inconsistent, the subsequent operations may be continued. For example, the network side device is continuously requested to deliver the updated key, and then the update operation is continued to ensure that the update is successful. The above preferred embodiments are further described below in conjunction with the examples of FIGS. 3 and 4. Example 1: FIG. 3 is a flow chart of a method for updating a PWS key according to Example 1 of the present invention. As shown in FIG. 3, this example shows a process in which a network side device actively sends an updated PWS key to a UE. This flow gives a flow chart of the LTE network, which is similar for the GSM/UMTS network, as long as the MME is replaced by the SGSN. In this process, the UE successfully receives the updated key information sent by the network side, and the specific steps are as follows: Step S302: The CBC sends a PWS key (key) to be updated to the network side device (for example, the MME) and the The identifier of the PWS key (key id); Step S304: After receiving the delivered key message, the MME saves the key and sends a response message to the CBC. It should be noted that: Steps S302 and S304 are an MME trigger. The case of the key update may also include other situations, such as the expiration of the key usage period in the MME, and the subsequent examples are the same; Step S306: The MME prepares to actively send the updated PWS key to the UE. If the NAS layer connection of the UE exists in the MME, the MME directly sends the NAS layer connection, and then the MME first sends the PWS key information, including the key and the NAS, to the UE. The corresponding key ID. The NAS layer message may be a notification message (NOTIFICATION) or the like; Step S310: The UE updates the locally saved current key information by using the newly received key information. Step S312: After the MME sends the PWS key information, the interval is separated. After the time, the current PWS key ID is broadcast to the UE through the base station device. The interval may be determined by a specific device by using a timer or other methods, and the interval time is determined by a specific device. Step S314: After receiving the broadcast PWS ID, the UE determines whether the locally saved and the received ones are consistent. Then the PWS key update is successful. Example 2: Figure 4 is a flow chart of a method for updating a PWS key according to Example 2 of the present invention. As shown in FIG. 4, the example shows that the network actively sends an updated PWS key to the terminal, and the UE does not successfully receive the exception handling process. This flow gives a flow chart of the LTE network. It is similar for the GSM/UMTS network, as long as the MME is replaced with the SGSN. The specific steps are as follows: Step S402: The CBC sends a PWS key (key) and an identifier (key id) of the PWS key to the MME. Step S404: After receiving the issued key message, the MME saves the key. Key information, and send a response message to the CBC; Step S406: The MME prepares to actively send the updated PWS key to the UE. If the NAS layer connection of the UE exists in the MME, the PWS key is directly sent; otherwise, the MME first triggers the establishment of the NAS layer connection, and then sends the same; Step S408: The MME sends the PWS key to the UE by using the non-access stratum (NAS layer) message. Information, including the key and the corresponding key ID. For example, the NAS layer message may be an announcement message NOTIFICATION or the like; Step S410: The UE updates the locally saved information using the newly received key. It should be noted that the UE may receive the NAS layer message, or may not receive it; or the received content is incorrect or the like; therefore, the UE may update the current PWS key by using the received PWS key. abnormal. Step S412: After the PGW sends the PWS key information, the MME broadcasts the current PWS key ID to the UE through the base station device. The time interval may be a timer mode, and the interval time is determined by a specific device. Step S414: After receiving the broadcast PWS ID, the UE determines that the local save is inconsistent with the received one, possibly due to step S408 and / or step S410 abnormally caused; Step S416: After the UE is separated for a period of time, the tracking area update message requests to update the PWS key, and the message carries the PWS key id to be requested. If it is a GERAN/UMTS network, the location area or the router is used to update the message. Step S418: After receiving the request message, the network side device sends a corresponding PWS key response message to the UE according to the PWS key id. As can be seen, FIG. 3 shows a case where the UE successfully updates the current PWS key with the received PWS key in step S204, and FIG. 4 shows that the UE adopts the received PWS key update in step S204. The current PWS key is abnormal, that is, no update is successful. Preferably, after the UE receives the identifier of the updated PWS key sent by the network side device, before the UE sends the request message for updating the current PWS key to the network side device, the following processing may be further included: the UE receives the The PWS message delivered by the network side device, where the PWS message is encrypted by using the updated PWS key. The above preferred embodiment is further described below in conjunction with the example of FIG. Example 3: Figure 5 is a flow chart of a method for updating a PWS key according to Example 3 of the present invention. As shown in FIG. 5, this embodiment shows that the network actively sends updated PWS key information to the terminal, and the process of receiving the PWS message is received after the PWS key of the UE has not been updated successfully. This flow gives a flow chart of the LTE network. It is similar to the GSMAJMTS network, as long as the MME is replaced by the SGSN. The specific steps are as follows: Step S502: The CBC sends a PWS key (key) and an identifier (key id) of the PWS key to the MME. Step S504: After receiving the issued key message, the MME saves the key. Key information, and send a response message to the CBC; Step S506: The MME prepares to actively send the updated PWS key to the UE. If the NAS layer connection of the UE exists in the MME, the MME directly sends the NAS layer connection, and then the MME first sends the PWS key information to the UE, including the key and the NAS. The corresponding key ID. For example, the NAS layer message may be an advertisement message NOTIFICATION or the like; Step S510: The UE updates the locally saved information by using the newly received key information. Step S512: After the MME sends the PWS key information, after a period of time, The current PWS key ID is broadcast to the UE by the base station device. The interval may be determined by a specific device, and the interval time and the like may be determined by a specific device. Step S514: After receiving the broadcast PWS ID, the UE determines that the local save is inconsistent with the received one; Step S516: The UE receives the PWS message sent by the network side, and the PWS message is signed with the latest key. It should be noted that: Step S516 can occur at any time between step S512 and step S518. Step S518: After receiving the PWS message, the UE stops the current processing and starts the process of requesting the PWS key by the UE. It should be noted that: the UE uses the tracking area update message to request to update the PWS key, and the message carries the PWS key id to be requested. If it is a GERAN/UMTS network, the location area or the router is used to update the message. Step S520: After receiving the request message, the network side sends the corresponding PWS key to the UE according to the PWS key id. Preferably, when the UE updates the current PWS key by using the received PWS key, the following processing may also be included:

(1) The UE receives the PWS message sent by the network side device, where the PWS message is encrypted by using the updated PWS key;

(2) The UE receives the identifier of the updated PWS key sent by the network side device; (3) in the case that the UE fails to authenticate the PWS message by using the current PWS key, the UE sends the update current to the network side device. a request message of the PWS key, where the request message carries an identifier of the updated PWS key;

(4) The UE receives the updated PWS key delivered from the network side device. The above preferred embodiment is further described below in conjunction with the example of FIG. 6. Example 4: Figure 6 is a flow chart of a method for updating a PWS key according to Example 4 of the present invention. As shown in FIG. 6, this embodiment shows a process in which the network actively sends updated PWS key information to the terminal, and the UE receives the PWS message without successfully receiving the updated PWS key information. This flow gives a flow chart of the LTE network. It is similar for the GSM/UMTS network, as long as the MME is replaced by the SGSN. The specific steps are as follows: Step S602: The CBC sends a PWS key (key) to be updated and an identifier of the PWS key to the MME.

(key id); Step S604: After receiving the delivered key message, the MME saves the key information and sends a response message to the CBC. Step S606: The MME prepares to actively send the updated PWS key to the UE. If the NAS layer connection of the UE exists in the MME, the MME directly sends the NAS layer connection, and then the MME first sends the PWS key information, including the key and the NAS, to the UE. The corresponding key ID. For example, the NAS layer message may be an announcement message NOTIFICATION or the like; Step S610: The UE updates the locally saved information by using the newly received key information. It should be noted that, in this example, the UE update key is not successful because An abnormality occurs in step S608 or step S610. For example, an abnormal situation occurs in which the UE does not receive the NAS layer message or the received content is incorrect. Step S612: The UE receives the PWS message sent by the network side, and the PWS message is signed with the latest key. It should be noted that: Step S616 can occur at any time between step S608 and step S612. Step S614: After the PGW sends the PWS key information, the MME broadcasts the current PWS key ID to the UE through the base station device. The interval may be in a timer mode, and the interval time is determined by a specific device. Step S616: After receiving the PWS message, the UE stops the current processing and starts the process of requesting the PWS key by the UE. It should be noted that: the UE uses the tracking area update message to request to update the PWS key, and the message carries the PWS key id to be requested. If it is a GERAN/UMTS network, the location area or the router is used to update the message. Step S618: After receiving the request message, the network side sends the corresponding PWS key to the UE according to the PWS key id. FIG. 7 is a flowchart of a method for updating a PWS key according to Embodiment 2 of the present invention. As shown in FIG. 7, the method mainly includes the following processing: Step S702: When a preset condition is met, the network side device is triggered to send updated PWS key information, where the PWS key information includes a PWS key; Step S704: The network side device sends the updated PWS key to the UE by using the non-access stratum downlink message, so that the UE updates the current PWS key by using the received PWS key. In the related art, there is currently no method for how to update the PWS key. The method shown in FIG. 6 is adopted, when the preset condition is met, the network side device is triggered to send the updated PWS key; the network side device sends the updated PWS key to the UE through the non-access stratum downlink message, so that The UE uses the received PWS key to update the current PWS key, and solves the problem that the related technology does not involve updating the PWS key, and implements the real-time update of the PWS key to strengthen the security protection of the PWS. Preferably, the PWS key information further includes an identifier of the PWS key, and after the UE receives the updated PWS key information sent by the network side device by using the non-access stratum downlink message, the method further includes: the UE saving the PWS key Logo. Preferably, the non-access stratum downlink message may include, but is not limited to: an announcement message. Preferably, the foregoing preset condition may include but is not limited to one of the following:

(1) reaching a predetermined duration; wherein, the predetermined duration may be preset by using a timer or other means for the usage period of the PWS key;

(2) The network side device receives the key update message sent by the cell broadcast center CBC, where the key update message includes: the updated PWS key and the identifier of the PWS key. Preferably, after the UE updates the current PWS key by using the received PWS key, the method further includes: sending, by the network side device, an identifier of the updated PWS key. When the identifier ID of the current PWS key of the UE is consistent with the identifier ID of the PWS key sent by the network side device, it indicates that the UE updates the PWS key successfully. Preferably, the manner in which the network side device sends the updated PWS key may include, but is not limited to, a broadcast message delivery mode. For further description of the above preferred embodiments, reference may be made to FIG. 3, and details are not described herein again. Preferably, after the network side device sends the identifier of the updated PWS key, the method may further include: if the identifier of the PWS key saved by the UE does not include the The updated PWS key, the UE initiates a PWS key update procedure, and requests the updated PWS key from the network side device. Preferably, the UE initiates a PWS key update procedure, and requesting the updated PWS key from the network side device may include the following processing:

(1) The network side device receives the request message for updating the current PWS key from the UE, where the request message carries the identifier of the updated PWS key; (2) the network side device delivers the updated PWS key. For further description of the above preferred embodiments, reference may be made to FIG. 4, and details are not described herein again. Preferably, after the network side device sends the identifier of the updated PWS key, before the network side device receives the request message for updating the current PWS key from the UE, the network side device may further include: sending, by the network side device, a PWS message, Among them, the PWS message is encrypted with the updated PWS key. For further description of the above preferred embodiments, reference may be made to FIG. 5, and details are not described herein again. Preferably, when the UE updates the current PWS key by using the received PWS key, the following processing may also be included:

(1) The network side device delivers the PWS message, where the PWS message is encrypted by using the updated PWS key; (2) the identifier of the updated PWS key sent by the network side device;

(3) In the case that the UE fails to authenticate the PWS message by using the current PWS key, the network side device receives a request message for updating the current PWS key from the UE, where the request message carries the updated PWS key. Identification

(4) The network side device delivers the updated PWS key. For further description of the above preferred embodiments, reference may be made to FIG. 6 and details are not described herein again. FIG. 8 is a structural block diagram of an apparatus for updating a PWS key according to Embodiment 1 of the present invention. As shown in FIG. 8, the device for updating the PWS key may include: a first receiving module 800, configured to receive an updated PWS sent by a network side device through a non-access stratum downlink message when the preset condition is met. Key information, wherein the PWS key information includes a PWS key; and the updating module 802 is configured to update the current PWS key with the received PWS key. In the updating device of the PWS key shown in FIG. 8, when the preset condition is met, the network side device receives the updated PWS key sent by the non-access stratum downlink message, and the first receiving module 800 receives the PWS key. The update module 802 updates the current PWS key by using the received PWS key, thereby solving the problem that the related technology does not involve updating the PWS key, and realizing the security of the PWS by real-time updating of the PWS key. protection. Preferably, as shown in FIG. 9, the foregoing apparatus may further include: a saving module 814, configured to save an identifier of the PWS key. Preferably, the non-access stratum downlink message may include, but is not limited to: an announcement message. Preferably, the preset condition may include, but is not limited to, one of the following: (1) reaching a predetermined duration; in a specific implementation process, the predetermined duration may be preset by using a timer or the like for the usage period of the PWS key;

(2) The network side device receives the key update message delivered by the cell broadcast center (CBC), where the key update message includes: the updated PWS key and the identifier of the PWS key. Preferably, as shown in FIG. 9, the foregoing apparatus may further include: a second receiving module 804, configured to receive an identifier of an updated PWS key sent by the network side device; and a determining module 806, configured to determine the saved Whether the identifier of the updated PWS key is included in the identifier of the PWS key, and if included, the update is successful. Preferably, the manner in which the network side device sends the updated PWS key may include, but is not limited to, a broadcast message sending manner. Preferably, as shown in FIG. 9, the foregoing apparatus may further include: a sending module 808, configured to: when the output of the determining module is negative or the operation of the first receiving module or the updating module is abnormal, The network side device sends a request message for updating the current PWS key, where the request message carries an identifier of the updated PWS key; and the third receiving module 810 is configured to receive the device from the network side device. The updated PWS key sent. Preferably, as shown in FIG. 9, the foregoing apparatus may further include: a fourth receiving module 812, configured to receive a PWS message sent by the network side device, where the PWS message is encrypted by using an updated PWS key. of. It should be noted that, when the first receiving module 800 and the updating module 802 are working normally, if the updating module 802 updates the PWS key successfully, the device may decrypt the PWS by using the updated key. If the first receiving module 800 or the updating module 802 works abnormally, and the updating module 802 does not update the PWS key, the PWS message sent by the network receiving device received by the fourth receiving module 812 needs to be in the following two manners. One of the processes: mode 1: if the fourth receiving module 812 receives the PWS message sent from the network side device, and before the second receiving module 804 receives the identifier of the updated PWS key sent by the network side device, The determining module 806 stops working, and the sending module 808 sends a request message for updating the current PWS key to the network side device, and the third receiving module 810 receives the updated PWS key sent by the network side device. Manner 2: After the fourth receiving module 812 receives the PWS message sent by the network side device, and after the second receiving module 804 receives the identifier of the updated PWS key sent by the network side device, the sending module 808 is Before the network side device sends the request message for updating the current PWS key, the determining module 806 continues to perform the determining work, and then the sending module 808 sends a request message for updating the current PWS key to the network side device, and The three receiving module 810 receives the updated PWS key delivered by the network side device. FIG. 10 is a structural block diagram of an apparatus for updating a PWS key according to Embodiment 2 of the present invention. As shown in FIG. 10, the device for updating the PWS key may include: a triggering module 1000, configured to trigger the network side device to send updated PWS key information when the preset condition is met, where the PWS key information includes The first sending module 1002 is configured to send the updated PWS key through the non-access stratum downlink message, so that the UE updates the current PWS key by using the received PWS key. In the updating device of the PWS key shown in FIG. 10, when the preset condition is met, the triggering module 1000 triggers the network side device to send the updated PWS key; the first sending module 1002 sends the downlink message through the non-access stratum. The updated PWS key is used to enable the UE to update the current PWS key by using the received PWS key, thereby solving the problem that the related technology does not involve updating the PWS key, and realizing the real-time update by the PWS key. Strengthen the security protection of PWS. For example, the foregoing non-access stratum downlink message may include, but is not limited to: an advertisement message. Preferably, the foregoing preset condition may include but is not limited to one of the following:

(1) reaching a predetermined duration; in a specific implementation process, the predetermined duration may be preset by using a timer or the like for the usage period of the PWS key; (2) The network side device receives the key update message delivered by the cell broadcast center (CBC), where the key update message includes: the updated PWS key and the identifier of the PWS key. Preferably, as shown in FIG. 11, the foregoing apparatus may further include: a second sending module 1004, configured to send an identifier of the updated PWS key. Preferably, the manner in which the network side device sends the updated PWS key may include, but is not limited to, a broadcast message sending manner. Preferably, as shown in FIG. 11, the apparatus may further include: a fifth receiving module 1006, configured to receive a request message from the UE for updating a current PWS key, where the request message carries an updated PWS key The third sending module 1008 is configured to deliver the updated PWS key. Preferably, as shown in FIG. 11, the foregoing apparatus may further include: a fourth sending module 1010, configured to send

A PWS message, wherein the PWS message is encrypted using an updated PWS key. It should be noted that the PWS message sent by the fourth sending module 1010 may be sent by the first sending module 1002 to send an updated PWS key through the non-access stratum downlink message, and the fifth receiving module 1006 receives the update from the UE. Any moment between the request message of the current PWS key. From the above description, it can be seen that the present invention achieves the following technical effects: Before the current PWS key usage period expires, the current PWS key is updated, and the new PWS key can be successfully enabled, and the solution is solved. The related art does not address the problem of how to update the PWS key, thereby achieving the effect of enhancing the security protection of the PWS by real-time updating of the PWS key. Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps are fabricated as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention. Industrial applicability The technical solution of the present invention updates the current PWS key before the expiration of the current PWS key expiration period, and can successfully enable the new PWS key, thereby solving the technical solution that the PWS key is not updated in the related art. The problem, in turn, achieves the effect of enhancing the security protection of the PWS by real-time updating of the PWS key.

Claims

Claim

1. A public alarm system PWS key update method, including:

When the preset condition is met, the user equipment UE receives the updated PWS key information sent by the network side device through the non-access stratum downlink message, where the PWS key information includes a PWS key;

The UE updates the current PWS key with the received PWS key.

The method of claim 1, wherein the PWS key information further includes an identifier of a PWS key, and the UE receives a downlink message from the network side device by using the non-access layer. After the updated PWS key information, the method further includes: the UE saving the identifier of the PWS key.

3. The method according to claim 1, wherein the preset condition comprises one of the following:

Reach the predetermined length of time;

The network side device receives the key update message sent by the cell broadcast center CBC, where the key update message includes: the updated PWS key and the identifier of the PWS key.

The method of claim 2, after the UE uses the received PWS key to update the current PWS key, the method further includes:

The UE receives an identifier of the updated PWS key that is sent by the network side device; the UE determines whether the saved PWS key includes the received PWS key. The identifier, if included, is updated successfully.

The method according to claim 4, wherein, when the UE determines whether the identifier of the updated PWS key is included in the identifier of the saved PWS key, the method further includes:

If the identifier of the PWS key that is saved by the UE does not include the identifier corresponding to the received PWS key, the UE initiates a PWS key update procedure, and requests an update from the network side device. PWS key.

The method of claim 5, wherein the UE initiates a PWS key update process, and the requesting, by the network side device, the updated PWS key comprises:

Sending, by the UE, a request message for updating the current PWS key to the network side device, where the request message carries an identifier of the updated PWS key; The UE receives the updated PWS key delivered by the network side device.

The method according to claim 6, wherein after the UE receives the identifier of the updated PWS key delivered by the network side device, the UE sends the identifier to the network side device Before updating the request message of the current PWS key, the method further includes:

The UE receives the PWS message sent by the network side device, where the PWS message is encrypted by using the updated PWS key.

The method according to claim 1, wherein, when the UE uses the received PWS key to update the current PWS key to be abnormal, the method further includes:

Receiving, by the UE, a PWS message sent by the network side device, where the PWS message is encrypted by using the updated PWS key;

The UE receives an identifier of the updated PWS key that is sent by the network side device; in a case that the UE fails to authenticate the PWS message by using the current PWS key, the UE Sending, to the network side device, a request message for updating the current PWS key, where the request message carries an identifier of the updated PWS key;

The UE receives the updated PWS key delivered by the network side device.

The method according to any one of claims 1 to 8, wherein the non-access stratum downlink message comprises: an announcement message.

10. A public alarm system PWS key update method, including:

When the preset condition is met, the network side device is triggered to send the updated PWS key information, where the PWS key information includes a PWS key;

And the network side device sends the updated PWS key to the user equipment UE by using a non-access stratum downlink message, so that the UE updates the current PWS key by using the received PWS key.

The method according to claim 10, wherein the preset condition comprises one of: reaching a predetermined duration;

The method according to claim 10, after the UE uses the received PWS key to update the current PWS key, the method further includes: the network side device delivering the updated The ID of the PWS key.

The method according to claim 12, wherein the manner in which the network side device delivers the updated PWS key comprises: a broadcast message delivery mode.

The method according to claim 12, further comprising: after the network side device sends the identifier of the updated PWS key,

If the updated PWS key sent by the network side device is not included in the identifier of the PWS key saved by the UE, the UE initiates a PWS key update procedure, and requests the network side device The updated PWS key.

The method of claim 14, wherein the UE initiates a PWS key update procedure, and the requesting, by the network side device, the updated PWS key comprises:

The network side device receives a request message for updating the current PWS key from the UE, where the request message carries an identifier of the updated PWS key;

The network side device delivers the updated PWS key.

The method according to claim 15, wherein after the network side device sends the identifier of the updated PWS key, the network side device receives an update from the UE to the current Before the request message of the PWS key, it also includes:

The network side device sends a PWS message, where the PWS message is encrypted by using the updated PWS key.

The method according to claim 10, wherein, when the UE updates the current PWS key by using the received PWS key, the method further includes:

The network side device sends a PWS message, where the PWS message is encrypted by using the updated PWS key;

Sending, by the network side device, an identifier of the updated PWS key;

In a case that the UE fails to authenticate the PWS message by using the current PWS key, the network side device receives a request message for updating the current PWS key from the UE, where The request message carries an identifier of the updated PWS key;

The network side device delivers the updated PWS key.

The method according to any one of claims 10 to 17, wherein the non-access stratum downlink message comprises: an announcement message.

19. A public alarm system PWS key update device, comprising:

The first receiving module is configured to: when the preset condition is met, receive the updated PWS key information that is sent by the network side device by using the non-access stratum downlink message, where the PWS key information includes a PWS key;

The update module is set to update the current PWS key with the received PWS key.

The device according to claim 19, wherein the PWS key information further includes an identifier of the PWS key, and the device further includes:

The save module is set to save the identifier of the PWS key.

The device according to claim 20, wherein the device further comprises:

a second receiving module, configured to receive an identifier of the updated PWS key delivered by the network side device;

The judging module is configured to determine whether the identifier of the updated PWS key is included in the identifier of the saved PWS key, and if yes, the update succeeds.

The device according to claim 21, wherein the device further comprises: a sending module, configured to: when the output of the determining module is negative or the operation of the first receiving module or the updating module is abnormal, Sending, to the network side device, a request message for updating the current PWS key, where the request message carries an identifier of the updated PWS key; and a third receiving module is configured to receive from the network The updated PWS key delivered by the side device.

The device according to claim 19, wherein the device further comprises: a fourth receiving module, configured to receive a PWS message sent by the network side device, where the PWS message is The updated PWS key is encrypted.

24. A public alarm system PWS key update device, comprising:

The triggering module is configured to: when the preset condition is met, trigger the network side device to send the updated PWS key information, where the PWS key information includes a PWS key; The first sending module is configured to send the updated PWS key by using a non-access stratum downlink message, so that the UE updates the current PWS key by using the received PWS key.

The device according to claim 24, wherein the device further comprises:

The second sending module is configured to send the identifier of the updated PWS key.

The device according to claim 25, wherein the device further comprises:

a fifth receiving module, configured to receive a request message for updating the current PWS key from the UE, where the request message carries an identifier of the updated PWS key;

The third sending module is configured to deliver the updated PWS key.

27. The device according to claim 24, wherein the device further comprises:

The fourth sending module is configured to send a PWS message, where the PWS message is encrypted by using the updated PWS key.