WO2008083620A1

WO2008083620A1 - A method, a system and an apparatus for media flow security context negotiation

Info

Publication number: WO2008083620A1
Application number: PCT/CN2008/070042
Authority: WO
Inventors: Chengdong He; Zhanjun Zhang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2007-01-11
Filing date: 2008-01-08
Publication date: 2008-07-17

Abstract

A method, a system and an apparatus for media flow security context negotiation are provided. The calling user equipment (UE) sends the media flow security context information provided by itself to the called UE through the session request message. The media flow security context information includes security arithmetic. The calling UE receives the media flow security context information from the called UE, the calling UE and the called UE obtain the cipher key according to the media flow security context information comprising the security arithmetic provided by them. As a result of the calling UE and the called UE intercommunicating to obtain the media flow security context information comprising the security arithmetic and the cipher key directly without complicatedly computing from UE, and without the public key or other demands in the network, it realizes the media flow security context negotiation in IMS system, and it is propitious to process the media flow security protection in IMS network subsequently.

Description

Method, system and device for media stream security context negotiation

Technical field

The present invention relates to media stream encryption technologies, and in particular, to a method, system and apparatus for media stream security context negotiation. Background of the invention

The IP Multimedia Service Subsystem (IMS) is the core session control layer for fixed and mobile networks. It is one of the focuses of the development of the communications field and is already in the 3GPP, The Third Generation Partnership Project. IMS-related specifications are defined in the Telecommunications and Internet Converged Services and Protocols for Advanced Networking (TISPAN), such as: network architecture, interfaces, protocols, and so on.

Among them, security issues are an important aspect of 3GPP and TISPAN specifications. In order to ensure security, the IMS network is divided into an access domain and a network domain, and security specifications of the access domain and the network domain are respectively defined.

However, the current security specifications are for the control plane in the IMS network, that is, how to ensure the security of the session protocol in the IMS network, and the media stream itself is transmitted in plaintext. In this case, the user may be eavesdropped, tampered, etc. during the call, and the user's call security cannot be guaranteed.

The user equipment (UE, User Equipment) and the called UE perform security protection on the media stream, and both parties need to agree on the security context of the media stream. The media stream security context here mainly refers to security parameters such as a key used to encrypt the media stream, a security algorithm, a key identifier, and a validity period of the key. In the specific negotiation, the message can only carry some parameters, other The parameter may be a preset default parameter, such as a default key validity period, etc., and may continue to be carried and negotiated in subsequent messages. Currently, the existing Internet Engineering Task Force

There are more than 4 mechanisms for negotiating media stream security context information in IETF (Internet Engineering Tesk Force), such as RFC 3830 (RFC, Request for Comments) pre-shared key in the Multimedia Internet Keying (MIKEY) protocol. (PSK, Pre-Shared-Key) mode, Herman (DH, Deffi-Helman) mode, Public Key Infrastructure (PKI) mode, etc. The security information in RFC 4568 describes the SDES protocol. However, these protocols cannot be directly applied to the media stream security protection of IMS. For example, the MIKEY-DH mode requires high computing performance of the UE, but the current terminal capability cannot meet the requirements, so the MIKEY-DH mode cannot be directly applied. In IMS; for example, the MIKEY-PKI mode requires a public key facility, but the current IMS network does not have a PKI deployed, so the MIKEY-PKI mode cannot be directly applied to the IMS; for example, the MIKEY-PSK mode requires a caller. The key is shared with the called UE in advance, but there is no mechanism for sharing the key, so the MIKEY-PSK mode cannot be directly applied to the IMS. It can be seen that there is currently no way to solve the problem of media stream security in the IMS network. Summary of the invention

In view of this, the method embodiment of the present invention provides a method for media network security context negotiation, which can implement media stream security context negotiation in the IMS system, which is beneficial for the IMS system to use the key obtained by the negotiation to protect the media stream;

The embodiment of the present invention further provides a system for media stream security context negotiation, which can implement media stream security context negotiation in the IMS system, and is beneficial for the IMS system to use the key obtained by the negotiation to protect the media stream;

The embodiment of the invention further provides a device for media stream security context negotiation, which can negotiate media media security context in the IMS system, which is beneficial to the IMS system to obtain the confidentiality obtained through negotiation. The key protects the media stream.

In order to achieve the above first object, the technical solution provided by the embodiment of the present invention is: A method for implementing media stream security context negotiation, the method includes:

The calling terminal device UE sends the media stream security context information provided by itself to the called UE by using a session request message, where the media stream security context information includes a security algorithm; the calling UE receives the media stream provided by the called UE through the session response message. Security context information, the media stream security context provided by the called UE is determined according to media stream security context information provided by the calling UE;

The calling UE and the called UE obtain the key according to the media stream security context information provided by the two parties including the security algorithm.

In order to achieve the above first object of the present invention, an embodiment of the present invention also proposes another technical solution:

A method for implementing media stream security context negotiation, the method comprising:

The calling UE sends a session request message carrying the media stream protection indication information to the called party.

UE;

The called UE checks the media stream protection indication information to determine that it supports the media stream protection; the called UE and the calling UE obtain the media stream security context information including the security algorithm and the key.

For the second object of the present invention, the technical solution proposed by the embodiment of the present invention is: A system for implementing media stream security context negotiation, the system includes:

The calling UE sends the media stream security context information including the security algorithm provided by itself to the called UE through the session request message;

The called UE, the called UE determines the media stream security context information that needs to be provided according to the media stream security context information provided by the calling UE in the session request message, and sends the determined media stream security context information to the calling party through the session response message. UE; The calling UE and the called UE obtain a key according to the media stream security context information provided by the two parties including the security algorithm. .

For the second object of the present invention, the embodiment of the present invention further provides another technical solution: A system for implementing media stream security context negotiation, the system includes:

The calling UE sends a session request message carrying the media stream protection indication information to the called UE, and obtains media stream security context information including the security algorithm and the key;

The called UE receives the session request message carrying the media stream protection indication information, checks the media stream protection indication information, determines that it supports the media stream protection, and obtains the media stream security context information including the security algorithm and the key.

For the third object of the invention, the technical solution proposed by the invention is:

An apparatus for implementing media stream security context negotiation, the apparatus comprising:

The transceiver unit sends at least one set of media stream security context information provided by itself to the called UE by using a session request message, where each set of media stream security context includes a security algorithm; and receiving at least the called UE provides the session response message a set of media stream security context information, wherein the media stream security context provided by the called UE is selected according to at least one set of media stream security context information provided by the calling UE; and the generated key is carried in the selected one The set of media stream security context is sent to the called UE;

The selecting unit selects one set of all media stream security context information provided by the called UE;

The key generation unit generates a key according to the security algorithm in the selected media stream security context information.

In summary, the method, system and device for media stream security context negotiation proposed by the present invention do not require the UE to perform complex calculations, and do not need the public key facility in the network, but directly by the calling party. The UE interacts with the called UE to obtain media stream security context information including the security algorithm and the key, thereby implementing media stream security in the IMS system. Negotiation below facilitates subsequent media stream security protection in the IMS network. BRIEF DESCRIPTION OF THE DRAWINGS

1 is a flowchart of a method according to Embodiment 1 of the method of the present invention;

2 is a schematic diagram of a message flow according to Embodiment 2 of the method according to the present invention;

3 is a schematic diagram of a message flow according to Embodiment 3 of the method of the present invention;

4 is a schematic diagram of a message flow according to Embodiment 4 of the method of the present invention;

FIG. 5 is a schematic diagram of a message flow according to Embodiment 5 of the method of the present invention; FIG.

6 is a schematic structural diagram of a first embodiment of a system according to the present invention;

7 is a schematic diagram of a basic structure of a second embodiment of a system according to the present invention;

8 is a schematic structural diagram of a third embodiment of a system according to the present invention;

9 is a schematic diagram of a message flow according to Embodiment 6 of the method of the present invention;

10 is a schematic diagram of a message flow according to Embodiment 7 of the method of the present invention;

11 is a schematic diagram of a message flow according to Embodiment 8 of the method of the present invention;

12 is a schematic structural diagram of a fourth embodiment of a system according to the present invention;

12A is a schematic diagram showing the basic structure of Embodiment 5 of the system of the present invention;

12B is a schematic diagram showing the basic structure of a sixth embodiment of the system according to the present invention;

13A is a schematic diagram showing the basic structure of a seventh embodiment of the system according to the present invention;

FIG. 13B is a schematic diagram of the basic structure of Embodiment 8 of the system of the present invention. Mode for carrying out the invention

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the following detailed description will be made in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a flow chart of a first embodiment of the method of the present invention. As shown in FIG. 1, the method embodiment 1 includes the following steps: Step 101: The first entity sends a session establishment request message to the second entity, where the session establishment request message carries the media stream security capability information provided by the first entity side.

Step 102: The second entity determines, according to the session establishment request message, the media stream security capability information that is to be provided by the current side, and returns the provided media stream security capability information to the first entity by using the session establishment response message.

Step 103: The first entity generates a key according to the media stream security capability information provided by the current side and the media stream security capability information provided by the second entity side, and sends the generated key to the second entity.

The media stream security capability information provided by the first entity side may be the media stream security capability information provided by the first entity itself to the second entity, or may be the media stream security provided by the other entity on the first entity side to the second entity. Capability information. Correspondingly, the media stream security capability information provided by the second entity may be the media stream security capability information provided by the second entity itself to the first entity, or may be the media stream provided by the other entity on the second entity side to the first entity. Security capability information.

In the above media stream security capability negotiation method, only the first entity generates a key. Thereafter, the first entity side and the second entity side may protect the transmitted media stream by using a key generated by the first entity.

In a practical application, the second entity may also generate a key, which is specifically implemented as follows: after the step 103, the method further includes: the second entity according to the media stream security capability information provided by the first entity side and the media stream security capability information provided by the side Generate a key and send the generated key to the first entity. Thereafter, the first entity side and the second entity side may protect the transport media stream by using a key generated by both parties.

In an actual application, other entities on the second entity side may also generate a key, and send the generated key to the first entity. For example, the first entity is the UE, and the second entity is the MGCF/CSCF. After the step 103, the MGCF/CSCF sends the key generated by the UE. The media gateway MGW/media proxy MP, the MGW/MP generates a key according to the media stream security capability information provided by the UE and the media stream security capability information provided by the UE, and generates a key generated by itself to the calling UE through the MGCF/CSCF. .

Of course, after the two parties generate the key, the first entity side and the second entity side may not directly use the key generated by the two parties to transmit the media stream, but are respectively derived from the key generated by the side and the key generated by the opposite side. New key. Then, the first entity side and the second entity side reuse the derived key to transmit the media stream, and the purpose of protecting the media stream can also be achieved.

The first entity and the second entity in the present invention may be: a calling UE and a called UE, or a calling UE and a called side media gateway control function, whether the key is generated by one party or the key is generated by both parties. Entity (MGCF), or the calling UE and the calling side session control function entity (CSCF), or the called side CSCF and the called UE.

If the first entity and the second entity are the calling UE and the called UE, respectively, the method for negotiating the security capability may be referred to as a method for negotiating the media stream security capability of the user to the user; and if the first entity and the second entity The entity is called the UE and the calling side CSCF, or is the called side CSCF and the called UE, or the calling UE and the called side MGCF. The method of security negotiation can also be called the media stream security capability of the user to the network. The method of negotiation.

In the user-to-user media stream security capability negotiation method, that is, the first entity and the second entity are the calling UE and the called UE, respectively, and the media that can be directly protected by the key protection between the calling UE and the called UE Flow

In the media stream security capability negotiation method of the user to the network, if the first entity and the second entity are the calling UE and the called side MGCF, respectively, the media stream is not directly transmitted between the calling UE and the called side MGCF. The called side MGCF needs to send the key to the called side media gateway (MGW), and the media stream transmitted by the key protection between the calling UE and the called side MGW. Specifically divided into the following situations:

If only one party generates a key, when the called side MGCF receives the secret generated by the calling UE After the key is received, the received key is sent to the called side MGW; or

If both parties generate a key, the MGCF itself generates a key, and the key generated by the calling UE and the generated key are sent to the called side MGW; or when the called side MGCF generates the secret itself. After the key is generated, the key generated by the calling UE and the key generated by the calling party are derived from the new key, and the new key is sent to the called side MGW; or

If both parties generate a key, the called side MGCF first sends the key generated by the calling UE to the called side MGW, and the called side MGW regenerates the key, and returns the generated key through the called side MGCF. The calling side UE; or the calling UE and the called side MGW generate a new key according to the key generated by the local side and the opposite side. That is, the calling UE generates the generated key and the MGW. The key derives a new key, and the called side MGW derives a new key based on the key generated by the calling UE and the key generated by itself.

If the first entity and the second entity are the calling UE and the calling side CSCF, respectively, or the called side CSCF and the called UE, the media stream is not directly transmitted between them, and the primary/called side CSCF is also The key needs to be sent to the primary/called side media agent MP, and the media stream is transmitted by the key between the primary/called UE and the primary/called side MP. Take the calling UE and the calling side CSCF as examples, which are also divided into the following cases:

If only one party generates a key, the calling side CSCF sends the received key to the calling side MP after receiving the key generated by the calling UE; or

If both parties generate a key, the calling party CSCF generates a key, and the key generated by the calling UE and the generated key are sent to the calling side MP; or when the calling side CSCF generates the secret itself. After the key is generated, the key generated by the calling UE and the generated key are derived from the new key, and the new key is sent to the calling side MP; or

If both parties generate a key, the calling side CSCF first sends the key generated by the calling UE to the calling side MP, and the calling side MP regenerates the key, and returns the generated key through the calling side CSCF. Give the calling UE; or the calling UE and the calling side MP are based on the side and the opposite side. The resulting key derives a new key. That is to say, the calling UE derives a new key according to the key generated by the calling party and the key generated by the calling side MP, and the calling side MP derives a new key according to the key generated by the calling UE and the key generated by the calling UE. Key.

The situation of the called CSCF and the called UE is similar, and will not be described here.

The function of the MP is to process the data stream at the media level, and may be a functional unit of a functional entity such as a media resource processor (MRFP), a GPRS support node (GGSN), or a border gateway function entity (BGF), or may be A separate functional entity. 2 is a schematic diagram of a message flow of Embodiment 2 of the method of the present invention. In the second embodiment, the first entity is the calling UE, the second entity is the called UE, and the user-to-user security capability negotiation method is adopted, and both the first entity and the second entity generate a key.

As shown in FIG. 2, the method embodiment 2 includes the following steps:

Step 201: The calling UE sends a session establishment request message to the called UE, where the session establishment request message carries the media stream security capability information of the calling UE.

The session establishment request message described in this step is a session request message, such as an INVITE message, the media stream security capability information includes a security algorithm, and may also include a media type to be protected, a security transport protocol type, and security. One or a combination of any of the premise.

The security algorithm may be an integrity security algorithm or a confidentiality security algorithm, and the media type to be protected may be text, audio, video, etc., and the security transmission protocol type may be RTP/SAVP or RTP/SAVPF.

The security premise is used to indicate the security requirements of the media stream in the current session, and may include the strength identifier of the media stream security protection expected by the first entity, such as mandatory (mandatory), optional (optional), and negligible. ( none ). The security premise may also include a desired security negotiation configuration result and a current configuration situation, such as: whether to complete the negotiation, the receiving direction The security configuration, receiving, and sending methods have been completed to complete the security configuration.

In addition, the media stream security capability information of the calling UE may be used by the calling UE to provide the media stream security capability information of the called UE. For example, the calling UE can support five security algorithms, but only three security algorithms can be selected for the called UE. Then, the INVITE message can carry only three security algorithms provided. Of course, the calling UE can also provide the supported 5 security algorithms to the called UE. How to determine the provided media stream security capability information needs to be determined by the actual situation. The media stream security capability information here is equivalent to one or more sets of media stream security contexts, and each set of media stream security contexts includes a security algorithm.

Step 202: The called UE returns a session establishment response message carrying its own media stream security capability information to the calling UE.

The session establishment response message described in this step is a session response message, such as a 183 message, and the self-media stream security capability information is the media stream security capability information provided by the called UE, and can be supported by the calling UE. All or part of the information. For example, the called UE determines from the received INVITE message that the calling UE can support three security algorithms. If the called UE supports only two security algorithms, it can return all two types that can be supported to the calling UE. The security algorithm may also return one of the security algorithms to the calling UE. In practical applications, since the media stream security capability information is a general term for one or more sets of media stream security context information, and each set of media stream security context information includes a security algorithm, if the called UE returns one or One or more security algorithms may also be referred to as returning one or more sets of media stream security context information. That is, the called UE selects at least one set of media stream security context information supported by the media stream security context provided by the calling UE, and selects at least one set of media stream security context information as the media stream security provided by itself. Context information, and returned to the calling UE.

Step 203 to step 204: The calling UE according to its own media stream security capability information and is The media stream security capability information generated by the UE is generated to generate a key, and the generated key is sent to the called UE through a confirmation (PRACK) message.

Here, the calling UE may determine an algorithm from a security algorithm supported by both the calling UE and the called UE, and generate a key according to the algorithm. For example, if the key length requirement in the algorithm is 128 bits, a corresponding correspondence is generated. A 128-bit key. The generated key can be carried in the media stream security capability information. At the same time, the media stream security capability information carrying the key may further include information such as a key identifier, a key validity period, and the like. If the media stream security capability information is referred to as media stream security context information, that is, the calling UE may select one set from at least one set of media stream security context information provided by the called UE, and generate the generated key. It is carried in the selected media stream security context information, and is sent to the called UE by confirming the PRACK message. In actual applications, it can also be sent to the called UE through an UPDATE message.

Step 205 to step 206: The called UE generates a key according to the media stream security capability information of the UE and the media stream security capability information of the calling UE, and returns the generated key to the calling UE through the 200 message.

Similarly, the called UE may also carry the generated key in the media stream security capability information, and the media stream security capability information may further include information such as a key identifier, a key validity period, and the like. Here, if the media stream security capability information is referred to as the media stream security context information, after the called UE obtains the security context information of the media stream carrying the key returned by the calling UE, the media stream security context information may be determined. The security algorithm is a security algorithm supported by both parties, and the key can be generated directly according to the security algorithm.

At this time, both the calling UE and the called UE obtain the keys generated by both parties, and the transmitted media stream can be protected by the key. For example: The calling UE generates a key X, and the called UE generates a key Y. When the calling UE needs to transmit the media stream to the called UE, the media stream can be protected and transmitted to the called UE by using the key X/key ;; vice versa.

If there are multiple or more media streams to be transmitted, in steps 203 and 205, Different keys are generated for different media streams, and the key identifiers are used for distinguishing.

In the actual application, if only the calling UE generates the key, and the called UE and the calling UE use the same key to protect the media stream, step 205 and step 206 may be omitted; or if only the called UE needs to be generated. For the key, step 203 can be omitted. If the calling UE and the called UE need to use the derived key for encryption and decryption, after step 206, the method further includes: the calling UE and the called UE respectively derive a new key according to the keys generated by the two parties, and The derived key is used as a key to protect the media stream.

Certainly, in this embodiment, the security process is negotiated by using the call process. In the actual application, the process of negotiating the security capability may also be utilized. The method is similar to the embodiment, except that the message carrying the key or the media stream security capability information is different. Only.

After the security negotiation is completed in this embodiment, the call process will continue. For example, after the step 206, the calling UE also needs to send an update (UPDATE) message to the called UE, and the called UE returns a 200 message.

In addition, in this embodiment, the calling UE and the called UE transmit the key through the PRACK message and the 200 message. In practical applications, other messages, such as UPDATE messages and 200 messages, can also be used to transmit keys. 3 is a flow chart of Embodiment 3 of the present invention. In this embodiment, the first entity is the calling UE, and the second entity is the MGCF. In this embodiment, the second entity is the MGCF, and the called user is the user in the CS domain. After the call connection is established between the calling UE and the MGCF, the calling UE transmits the media stream through the MGW under the control of the MGCF.

As shown in FIG. 3, the method for implementing the media stream security negotiation in the fourth embodiment includes the following steps: Step 301: The calling UE sends a session establishment request message to the MGCF, where the session establishment request message carries the media stream security provided by the calling UE. Capability information.

This step is the same as step 201 of the second embodiment, and details are not described herein again. Step 302 ~ Step 303: The MGCF notifies the MGW to perform resource reservation, and the MGW returns a response message to the MGCF.

In this step, the resource reservation is that the MGCF instructs the MGW to add a real-time transport protocol (RTP) endpoint, etc., and how to perform resource reservation is a prior art, and is not described in detail herein.

Step 306: The MGCF returns a session establishment response message, that is, a 183 message, to the calling UE, where the 183 message carries the media stream security capability information supported by the MGW.

The media stream security capability information supported by the MGW may be all information provided by the calling UE and supported by the MGW, or may be part of the information selected by the MGCF from all the supported information.

Step 305 ~ Step 306: The calling UE generates a key according to the media stream security capability information provided by the UE and the media stream security capability information that the MGW can support, and sends the generated key to the MGCF through a PRACK message.

Step 307 to step 309: The MGCF generates a key according to the media stream security capability information supported by the MGW and the media stream security capability information provided by the calling UE, and sends the key generated by the calling UE and the generated key to the MGW. And receive the response message returned by the MGW.

In practical applications, the MGCF can send the key to the MGW by modifying the (MODIFY) message. Of course, the delivered information may also include information such as the type of media to be protected, the type of security transport protocol, the security algorithm, the key identifier, the key validity period, and the like.

Step 310: The MGCF returns the generated key to the calling UE through the 200 message. At this time, both the calling UE and the MGW on the called user side obtain the key, and the obtained key can be used to protect the transmission media stream.

Similar to the second embodiment, the calling UE and the MGW can also transmit the media stream using the derived key. Then, in step 307, the method further includes: the MGCF deriving the key generated by the calling UE and the key generated by the UE to generate a new key; The key. Correspondingly, after the step 310, the calling UE further needs to derive a new key according to the key generated by itself and the key generated by the MGCF.

In practical applications, the MGCF itself may not generate a key, but the MGW generates a key. In this way, the MGCF only needs to send the key generated by the calling UE to the MGW, and simultaneously sends the key generated by the MGW to the calling UE.

This embodiment describes an example in which both parties generate a key. In practical applications, if only the calling UE needs to generate a key, step 307 can be omitted; if only the MGCF needs to generate a key, 305 can be omitted.

Similar to the second embodiment, after the security negotiation is completed in this embodiment, the call process will continue. For example, after the step 310, the calling UE also needs to send an UPDATE message to the MGCF, and the MGCF returns a 200 message. 4 is a schematic diagram of a message flow of Embodiment 4 of the present invention. In this embodiment, the first entity is the calling UE, and the second entity is the calling side CSCF, and the method of user-to-network security capability negotiation is adopted, and both parties generate a key.

In this embodiment, the first entity and the second entity are both entities on the calling side. In actual application, when the calling UE initiates a call, the called side entity also needs to participate in the calling process, so the called side also has a corresponding The first entity and the second entity. The first entity and the second entity on the called side may also generate a key as the calling side, and use the key to perform media stream transmission. However, it should be noted that the security negotiation between the calling side and the called side is completely independent. For example, the calling side performs security negotiation and generates a key. The called side can not perform security negotiation and still adopt the normal calling process. That is to say, after the call ends, both the calling side and the called side can use the keys generated by each side to protect the media streams on each side, or only one side can protect the transmitted media stream by using a key.

In this embodiment, it is assumed that both the calling side and the called side perform security capability negotiation. As shown in FIG. 4, the method for implementing the media stream security negotiation in the fourth embodiment includes the following steps: Step 401: The calling UE sends a session establishment request message to the calling side CSCF, where the session establishment request message carries the media of the calling UE. Flow security capability information.

Similar to the second embodiment, the session establishment request message described in this step is an INVITE message, and the media stream security capability information includes a security algorithm.

Step 402: The calling side CSCF deletes the security algorithm of the calling UE in the session establishment request message, and sends the session establishment request message to the called side CSCF.

Since the security negotiation between the calling side and the called side is completely independent, the called side does not need to obtain the media stream security capability information provided by the calling UE. Therefore, the security algorithm provided by the calling UE can be deleted by the calling side CSCF. Of course, if the called side CSCF directly ignores the security algorithm of the calling UE in the session establishment request, it may not delete.

Step 403: The called side CSCF adds the security algorithm supported by the called side MP to the session establishment request message, and continues to send the session establishment request message to the called UE.

Step 404: The called UE returns a session establishment response message carrying its own media stream security capability information to the called side CSCF.

As in the second embodiment, the session establishment response message described in this step is a 183 message. Step 405: The called side CSCF records the media stream security capability information of the called UE, deletes the security algorithm of the called UE in the session establishment response message, and continues to return the session establishment response message to the calling side CSCF.

Step 406: The calling side CSCF adds the security algorithm supported by the calling side MP to the session establishment response message, and continues to return to the calling UE.

Similar to the step 202 of the second embodiment, the security algorithm supported by the calling MP may be all security algorithms provided by the calling UE and supported by the calling side MP, or may be the calling side CSCF from all the security algorithms. Part of the security algorithm selected.

Step 407 ~ Step 408: The calling UE according to its own media stream security capability information and the main The media stream security capability information returned by the side CSCF is generated to generate a key XI, and the generated key XI is sent to the calling side CSCF through a PRACK message.

The steps 407 to 408 are similar to the steps 203 to 204 in the second embodiment. Only the calling UE receives the media stream security capability information supported by the calling side MP provided by the calling side CSCF.

Step 409: The calling side CSCF records the media stream security capability information in the PRACK message, deletes the key XI and the security algorithm in the PRACK message, and continues to send the PRACK message to the called side CSCF.

Here, since the security negotiation between the calling side and the called side is independent, the called side does not need the key generated by the calling UE, so the related information such as the calling side key and the security algorithm in the PRACK message needs to be deleted. Of course, if the called side CSCF ignores the calling side key XI and the security algorithm in the PRACK message, it may not delete.

Steps 410 to 411: The called side CSCF generates a key Y1 according to the media stream security capability information supported by the called side MP and the media stream security capability information provided by the called UE, and adds the generated key Y1 to the PRACK message. Send to the called UE.

Steps 412 to 413: The called UE records the key Y1, and generates a key Y2 according to the media stream security capability information of the media stream and the media stream security capability supported by the MP on the called side, and returns the generated key Y2 through the 200 message. Give the called side CSCF.

Step 414 ~ Step 415: The CSCF of the called side sends the key Y1 and the key Y2 to the called side MP, deletes the key Y2 in the 200 message, and returns the 200 message to the calling side CSCF.

Step 416 to step 418: The calling side CSCF generates a key X2 according to the previously recorded media stream security capability information of the calling UE and the media stream capability information supported by the calling side MP, and then issues the key XI and the key X2. The calling side MP is added, and the generated key X2 is added to the 200 message to continue to return to the calling UE. At this time, the calling UE and the calling side CSCF obtain the key XI and the key X2, and the called side CSCF and the called UE obtain the key Y1 and the key Y2. In the process of transmitting the media stream later, the calling UE and the calling side CSCF will protect the transmission media stream by using the key XI and the key X2, and the called side CSCF and the called UE will protect and transmit by using the key Y1 and the key Y2. Media stream. That is to say, during the entire transmission process, the media stream is not protected in full, but is protected in segments.

Similar to the third embodiment, in step 417, the calling side CSCF may also not issue the key XI and the key X2 to the calling side MP, but derive the new key X by using the key XI and the key X2. , and the derived key X is sent to the calling side MP. Correspondingly, after step 418, the calling UE will also derive a new key X based on the key XI and the key X2. The situation described here is on the calling side, and the situation on the called side is similar, and will not be described here.

Similar to the third embodiment, the calling side CSCF itself may not generate a key, but the calling side MP generates a key. In this way, the calling side CSCF only needs to send the key generated by the calling UE to the MP, and then sends the key generated by the MP to the calling UE.

For the called party side, the called side CSCF itself may not generate a key, but the called side MP is a key, and the generated key is sent to the called UE through the called side CSCF; After the UE generates the key, the key generated by the called UE is sent to the called side MP through the CSCF on the called side.

This embodiment is described by taking the key generation by both parties. In actual applications, only one party can generate a key on the calling side and the called side. For example, if the calling side only needs to generate a key by the calling UE, step 417 may be omitted. If the calling side only needs the calling side CSCF to generate a key, step 407 may be omitted. Further, the calling side CSCF may send the key to the calling side MP after receiving the PRACK message in step 408, and does not have to wait until the 200 message is sent. Here, the case of the calling side is similar to the case of the called side. Certainly, similar to the second embodiment to the third embodiment, after the step 418 in this embodiment, the call further needs to continue to perform other processes, for example, the calling UE sends an UPDATE message to the called UE through the calling side CSCF and the called side CSCF, and Receive the returned 200 message, etc.

In addition, the CSCF described in this embodiment may be a CSCF of a proxy, that is, a P-CSCF, or a CSCF of a service, that is, an S-CSCF.

In the foregoing Embodiment 2 to Embodiment 4, the first entity needs to send the media stream security capability information to the second entity by using the session establishment request message, and the second entity returns the information provided by the second entity according to the media stream security capability information of the first entity. Media stream security capability information. In actual applications, the ability of the first entity and the second entity to support secure transmission of media streams may be different. In order for the second entity to flexibly select the media stream security capability information of the first entity, the first entity may set one or more media stream security capability information in advance, and the second entity selects one of the media stream security capability information.

FIG. 5 is a schematic diagram of a message flow of Embodiment 5 of a method for selecting a media stream security capability information. As shown in Figure 5, the method is:

Step 501: The first entity sends a session establishment request message to the second entity, where the session establishment request message includes one or more media stream security capability information.

Step 502 to step 503: The second entity selects one of the media stream security capability information, and determines the media stream security to be provided on the side according to the selected media stream security capability information and the media stream security capability information supported by the local side. The capability information is returned to the first entity by using the session establishment response message provided by the side.

The media stream security capability information may further include a priority. When the second entity selects the media stream security capability information, the second entity may select the priority according to the priority level, and select the highest level media stream security capability information that can be supported by the second entity. Media stream security capability information.

Embodiments of the present invention are described by taking an example in which the second entity can support secure transmission. of. In a practical application, if the second entity does not support the security algorithm provided by the first entity, or the second entity does not have the capability of securely transmitting the media stream, the second entity returns a failure response message when receiving the session establishment request message. , such as 4xx messages.

In this case, if the call is to be guaranteed to be successful, the basic session description configuration can be set in advance, and the basic session description configuration does not include the media stream security capability information. When the second entity cannot find the supported media stream security capability information in the received session establishment request message, or does not support the capability of selecting the media stream security capability information, the basic session description configuration may be directly provided as the first entity. With its own configuration, the subsequent call flow will proceed according to the prior art call flow.

Similar to the second embodiment, in the INVITE message sent by the first entity, the media stream security capability information may include a media type to be protected and a secure transmission protocol type in addition to the security algorithm. One or several arbitrary combinations of safety preconditions. In other messages that are exchanged between the first entity and the second entity, the media stream security capability information may also include one or a combination of any one of a media type, a security transport protocol type, and a security premise, and whether the key is included. And security algorithms are related to specific implementations. For example, in step 409 of the fourth embodiment, the calling side CSCF is required to delete the key and security algorithm in the media stream security capability information, and is not enumerated here.

Similar to the second embodiment, in the third to fifth embodiments, the generated key may be carried in the media stream security capability information and sent to the other party. In this case, the media stream security capability information may further include parameters such as a key validity period. If there are multiple media streams to be protected, a different key may be generated for each different media stream, and the media stream security capability information may further include a key identifier to distinguish the corresponding media stream.

In the second to fifth embodiments, the security algorithm may be carried as a crypto-suite parameter in the a =crypto header field in the Media Stream Security Description Protocol (SDES) defined in rfc 4568; the generated key, Key identification, key validity period, etc. can be in the SDES protocol The key-params parameter in the a=crypto header field is carried. Specifically, the key-method parameter can be used to indicate a key carrying method, such as an inline method. Use the key-info parameter to carry the key and parameters such as key identification and expiration date. The corresponding SRTP protocol in SDES can use the following i or: srtp-crypto-suite carries the security algorithm, and the srtp-key-method parameter indicates the key carrying method, for example, it is represented by inline header field, srtp-key The -info parameter carries parameters such as the key key identifier and validity period. For the a = crypto header field that only carries the algorithm and does not carry the key, you can just use the crypto-suite header field, or use the key field in the key-params parameter, but set the key-info parameter to a special value. There is no valid key, such as identifying the key-info field as a null value NULL, or setting it to a meaningless value.

In the second embodiment to the fifth embodiment, if the multimedia Internet key agreement (MIKEY) management protocol is adopted, the security algorithm, including the key length, the key generation rate, and the like, may be carried in the RFC 3830 MIKEY protocol. In the parameters defined in the Security Policy payload field. The generated key, key validity period, and the like can be carried in the key transfer payload (KEMAC, Key data transport payload) field. The entire MIKEY message can be carried in the a =key-mgmt SDP attribute field specified in RFC4567.

In the second embodiment to the fifth embodiment, the security algorithm may also be extended by a security algorithm header field in the Session Initiation Protocol (SIP); likewise, the generated key, the key identifier, the key validity period, and the like are also The corresponding header field can be extended in the SIP protocol to carry.

With the solution of the embodiment of the present invention, the first entity and the second entity in the call can obtain the key, thereby achieving the purpose of securely transmitting the media stream. Whether it is a user-to-user security capability negotiation method or a user-to-network security capability negotiation method, is a method of generating a key by one party, or a method of generating a key or further deriving a new key by both parties, first The specific content of the negotiation between the entity and the second entity, whether the negotiation process adopts The message in the process of the call, the use of the message in the call process, and the information in the negotiation process are carried in the message. The solution of the present invention can be applied according to the network deployment, and the media stream security capability negotiation proposed by the present invention is not discussed here. The method also provides a system for media stream security capability negotiation.

FIG. 6 is a schematic diagram showing the basic structure of Embodiment 1 of a media stream security capability negotiation system. As shown in Figure 6, the system includes:

The first entity 601 is configured to send a session establishment request message to the second entity 602, receive the returned session response message, and generate a key according to the media stream security capability information provided by the current entity and the media stream security capability information provided by the second entity 602. And sending the generated key to the second entity 602;

The second entity 602 is configured to receive the session establishment message sent by the first entity 601, provide the first entity media stream security capability information to the first entity 601, and receive the key generated by the first entity 601.

The first entity 601 includes a key generating unit 6011, configured to generate a key according to the existing media stream security capability information of the current side and the media stream security capability information provided by the second entity 602. The first entity 601 further includes The transceiver unit 6012 is configured to send and receive messages exchanged with the second entity 602.

Of course, if both parties need to generate a key, the second entity 602 may also include a key generation unit 6021 and a transceiver unit 6022, the functions of which are similar to those in the first entity 601, and will not be described in detail herein.

Here, the first entity 601 can be a calling UE, and the second entity 602 can be a called party.

UE.

The first entity 601 may also be a calling UE, and the second entity 602 is an MGCF. The system further includes an MGW for receiving a key delivered from the MGCF.

The first entity 601 may also be the calling UE, and the second entity 602 is the calling side CSCF; or the first entity 601 is the called side CSCF, and the second entity is the called UE; in this case, the The system further includes an MP, configured to receive a key delivered from the CSCF.

Figure 7 is a schematic diagram showing the basic structure of the second embodiment of the system of the present invention. As shown in Figure 7, this embodiment includes:

The calling UE 701 is configured to send a session establishment message to the MGCF 702, receive the returned session response message, generate a key according to the media stream security capability information provided by the side and the media stream security capability information provided by the MGCF 702, and send the generated key. To MGCF702;

The MGCF 702 is configured to provide the calling UE 701 with the media stream security capability information that the MGW 703 can support, receive the key generated by the calling UE 701, and generate the confidentiality according to the media stream security capability information provided by the calling UE 701 and the media stream security capability information supported by the MGW 703. Key, the key generated by the calling UE 701 and the key generated by itself are sent to the MGW 703;

The MGW 703 is configured to receive a key that is delivered from the MGCF 702.

When the security capability negotiation is required, the calling UE 701 sends an INVITE message carrying the information about the security capability of the media stream to the MGCF 702. The MGCF 702 notifies the MGW 703 to perform resource reservation, and carries the media stream security capability information supported by the MGW 703 in the 183 message. The calling UE 701 generates a key X according to the media stream security capability information of the media stream and the media stream security capability information supported by the MGW 703, and carries the key X in the PRACK message and sends the key X to the MGCF 702. The MGCF 702 provides the message according to the calling UE 701. The media stream security capability information and the media stream security capability information supported by the MGW 703 generate a key Y, and the key X and the key Y are sent to the MGW 701, and the key Y is returned to the calling UE 701 through the 200 message.

At this time, both the calling UE 701 and the MGW 703 obtain the key X and the key Y, and the key stream X and the key Y can be used for media stream transmission to achieve the purpose of protecting the media stream. of course, The new key is also generated by the calling UE 701 and the MGCF 702 according to the key X and the key Y 4, and the MGCF 702 sends the derived key to the MGW 701.

Figure 8 is a schematic diagram showing the basic structure of a third embodiment of the system of the present invention. As shown in Figure 8, this embodiment includes:

The calling UE 801 is configured to generate a key XI according to the media stream security capability information and the media stream security capability information provided by the calling side CSCF 802, and send the generated key XI to the calling side CSCF 802;

The calling side CSCF 802 is configured to receive the key XI generated by the calling UE 801, generate a key X2 according to the media stream security capability information of the calling UE 801 and the media stream security capability information supported by the calling side MP 803, and generate the key XI and The key X2 is sent to the calling side MP803, and the key X2 is sent to the calling UE 801;

The called side CSCF 804 is configured to generate a key Y1 according to the media stream security capability information supported by the called side CSCF 806 and the media stream security capability information of the called UE 805, and send the generated key Y1 to the called UE 805 to receive the called party. The key Y2 generated by the UE 805, and the keys Y1 and Y2 are sent to the called side MP806;

The called UE 805 receives the key Y1 generated by the called side CSCF 806, and generates a key Y2 according to the media stream security capability information of the called side CSCF 806 and the media stream security capability information supported by the called side MP 806, and sends the key Y2 to The called side CSCF806.

When the media stream security capability negotiation is required, on the calling side, the calling UE 801 sends an INVITE message carrying the security information of the own media stream to the calling side CSCF 802. The calling side CSCF 802 secures the media stream supported by the calling side MP 803. The capability information is carried in the 183 message and returned to the calling UE 801. The calling UE 801 generates the key XI according to the media stream security capability information of the media stream and the media stream security capability information supported by the calling side MP 803, and carries the key XI to the PRACK message. Transmitted to the calling side CSCF 802; the calling side CSCF 802 according to the media stream security capability information provided by the calling UE 801 and the media stream security capability supported by the MP 803 The force information generates a key X2, and the key XI and the key X2 are sent to the MP 803, and the key X2 is returned to the calling UE 801 through the 200 message. As for the called side, the situation is similar to that of the calling side, and will not be described in detail here.

The entity of the system embodiment 1 and the system embodiment 2 further includes a key generation unit and a transceiver unit, and the functions and structures thereof are the same as those in FIG. 6, and details are not described herein again.

The methods and systems for implementing media stream security capability negotiation are described in the above Figures 1 to 8. In actual applications, the media stream security capability information may include one or more sets of media stream security capability context information, and the media stream security capability negotiation may also be referred to as media stream security context negotiation. In addition, the method for performing media stream security context negotiation between the calling UE and the called UE is described in the second embodiment of the method, and the present application further proposes several other calling UEs in the following method embodiment 6 to method embodiment 8. A method of media stream security context negotiation between the called UE and the called UE.

FIG. 9 is a schematic diagram of a message flow of Embodiment 6 of the method of the present invention. In the sixth embodiment of the method, the first entity is the calling UE, and the second entity is the called UE. In an actual application, the first entity and the second entity may also be MGCF/MGW, and the specific process is similar to the following, and this embodiment is not separately described.

The second embodiment of the method is the same as the method embodiment 6. The calling UE sends the media stream security context information provided by the calling UE to the called UE through the session request message, where the media stream security context information includes a security algorithm; The UE receives the media stream security context information provided by the called UE through the session response message, and the media stream security context provided by the called UE is determined according to the media stream security context information provided by the calling UE; the calling UE and the called party The UE obtains a key according to the media stream security context information provided by the two parties including the security algorithm.

For the case where the calling UE and the called UE obtain the key according to the media stream security context information provided by the two parties including the security algorithm, refer to the method embodiment 2 and the method. Example 6 of the law. The method embodiment 6 may be as shown in FIG. 9 and may include the following steps: Step 901: The calling UE generates a key generation parameter Pa of the local side.

In this step, Pa is a parameter used to generate a media stream security key, and a random number (nonce) generated by the prior art may be used in the specific implementation.

Step 902: The calling UE sends a session request message to the called UE, where the media stream security context information provided by the calling UE is carried. For example: The calling UE provides two sets of media stream security context information, which can be expressed as: (Algorithm 1, Pal); (Algorithm 2, Pa2).

The session request message described in this step is an invitation (INVITE) message of the session initiation protocol SIP, and may also be an update (UPDATE) message. The media stream security context information includes at least a key generation parameter Pa and a security algorithm, and may also include one or both of a key lifetime and a key identifier. The session request message may include at least one set of media stream security context information, which is selected by the called UE, where each set of media stream security context information may be arranged according to priority or each set is added with a corresponding priority indication. Indicates the priority of the caller's choice of security context information for each set of media streams. In addition, if there are multiple sets of media stream security context information, then step 901 will generate respective key generation parameters for each set of media stream security contexts.

The media security algorithm herein may be one or a combination of an integrity security algorithm or a confidentiality security algorithm.

Step 903: After the called UE receives the session request message, the key generation parameter Pb of the local side is generated.

Step 904: The called UE sends a 183 response message to the calling UE, where the media stream security context information provided by the side is carried. For example (algorithm 2, Pb)

Here, the media stream security context information provided by the called UE is the media stream security context information that the called UE needs to provide according to all the media stream security context information provided by the calling UE in the session request message. In other words, if the calling UE mentions the called UE When at least one set of media stream security context information is provided, the called UE selects and determines a set from all media stream security context information provided by the calling party according to the situation supported by itself, as the media stream security provided by the calling UE to itself. Contextual information. Certainly, the called UE does not directly send the selected media stream security context information to the calling UE, and needs to send its own key generation parameter as the key generation parameter in the selected media stream security context information to the calling party. The UE, ie the media stream security context information sent to the calling party should include the key generation parameter Pb and the corresponding selected security algorithm.

In addition, if the calling UE only provides a set of media stream security context information, the called UE may also not select, and the calling UE and the called UE obtain the key according to the media stream security context information provided by the two parties including the security algorithm. The method is: the called UE generates a key according to the key generation parameter in the media stream security context provided by the calling UE and the key generation parameter thereof, and the calling UE is in accordance with the media stream security context provided by the called UE. The key generation parameter and its own key generation parameters generate a key.

In practical applications, the session response message described in this step may also be a 200 response message. Step 904': The called UE derives a media stream security key according to the key generation parameters Pa and Pb.

The parameter Pa of this step is a key generation parameter in the media stream security context selected by the called UE, and the parameter Pb is a key generation parameter of the called UE, that is, the called UE is in accordance with the selected media stream security context. The key generation parameter and its own key generation parameters generate a key.

Here, steps 904 and 904 have no inevitable sequence. In actual applications, the key generation parameters in step 901 and step 903 may also be existing, or generated by the calling UE and the called UE in advance, and need not be temporarily generated in this process.

Step 905: After receiving the response message sent by the called UE, the calling UE derives the media stream security key according to the key generation parameters Pa and Pb. Similarly, in this step, the calling UE generates a key according to the key generation parameter Pb and the key generation parameter Pa in the media stream security context sent by the called UE in step 904.

Here, the method of deriving a key may use a key generation function specified by the calling UE and the called UE in advance, for example, using the following function:

KEY = KDF (Pa , Pb , [other])

KEY is the key of the derived encrypted media;

KDF is a key generation function, specifically a hash Hash function can be used.

[other] is other related parameters, such as the identifier of the RTP stream, SSRC, etc., so that it can be used to further generate a key for each RTP stream; or [other] represents the length of the key of the KEY to be generated; You can not use the [other] parameter.

Thereafter, the calling UE and the called UE also need to continue the subsequent call flow.

Since both the calling UE and the called UE obtain the key, the obtained media key can be protected by the obtained key.

In this embodiment, the security algorithm may be carried by using the a=crypto header field in the Media Stream Security Description Protocol (SDES) defined in RFC 4568 as a crypto-suite parameter; the key generation parameters Pa and Pb, and the secret Key parameters such as key identifier and key validity period can be carried in the key-params parameter in the S= protocol a =crypto header field. Specifically, the key-method parameter can be used to indicate the method, such as inline method or key-method- A new method of ext extension, using the key-info parameter to carry parameters such as key generation parameters Pa and Pb and key identification and validity period. The header field in the SDES protocol corresponding to the SRTP protocol can be used as follows: The srtp-crypto-suite header field carries a security algorithm, and the srtp-key-method parameter indicates a carrying method, such as an inline method or a key-method. A new method of -ext extension, the srtp-key-info parameter carries parameters such as key generation parameters Pa and Pb and key identification and expiration date. Using SDES to carry multiple sets of media stream security context information can be carried by multiple a = crypto header fields, and the priority information can be followed. a = the ordering identifier of the crypto header field.

In this embodiment, if a multimedia internet key agreement (MIKEY) management protocol is adopted, a security algorithm, a security context including a key length, a key generation rate, and the like may be carried in the RFC 3830 MIKEY protocol. The policy payload ) is in each of the parameters defined in the field. The key generation parameters Pa and Pb may be carried in a Key data sub-payload field in a Key Transfer Transport (KEMAC) field in MIKEY. The entire MIKEY message can be carried in the attribute field of a =key-mgmt SDP specified in RFC4567. Multiple sets of a =key-mgmt header fields can also carry multiple sets of media stream security context information, and the priority information can be identified according to the order of a =key-mgmt header fields.

The method embodiment 7 and the method embodiment 8 have the following features in common: the calling UE sends a session request message carrying the media stream protection indication information to the called UE; the called UE checks the media stream protection indication information, and determines the self. Media stream protection is supported, and the called UE and the calling UE obtain a media stream security context including a security algorithm and a key.

That is, when the received media stream protection indication information is received, the called UE may determine the media stream request protection of the current session according to the media stream protection indication information, and determine whether it supports the media stream protection. If it supports itself, it may continue to perform. This process. In practical applications, if the called UE determines that it does not support media stream protection, it can directly end the session.

The method for how the called UE and the calling UE obtain the media stream security context information including the security algorithm and the key may include the following three methods:

The first method is: the called UE sends at least one set of media stream security context information provided by itself to the calling UE, and each set of media stream security context information includes a security algorithm and a corresponding key; the calling UE directly from the A set of all media stream security context information sent by the UE is selected, and the selected set of media stream security context information is sent to the called UE. That is, since the key already exists in the media stream security context information provided by the called UE, the calling UE only needs to select one set and notify the called UE, and both parties can determine the security algorithm and the corresponding key, thereby achieving The purpose of the consultation.

Of course, in a practical application, the calling UE selects one set of all media stream security context information sent by the called UE, and sends the selected set of media stream security context information to the called UE. The method further includes: the calling UE uses the new key generated by itself as a key in the selected set of media stream security contexts.

That is, although the media stream security context information selected by the calling UE is provided by the called UE, the calling UE can also determine the key by itself, but the determined key needs to conform to the selected media stream security context. The rules of the security algorithm can be used.

The second method is: the called UE sends at least one set of media stream security context information provided by itself to the calling UE, and each set of media stream security context information includes a security algorithm and a corresponding key; the calling UE is called from the called party. Selecting at least one set of media stream security context information supported by the UE, and selecting at least one set of media stream security context information to be sent to the called UE; the called UE from the calling party A set of at least one set of media stream security context information provided by the UE is selected and sent to the calling UE.

That is to say, the calling UE can select the media stream security context information provided by the called UE, but finally decide which set to use is still determined by the called UE, where the calling UE can also generate a new key generated by itself. As a key in the selected set of media stream security contexts. In this way, after negotiation, both parties can determine the security algorithm and the corresponding key, and also achieve the purpose of negotiation.

The third method is: the called UE returns the media stream protection indication information to the calling UE; the calling UE checks the media stream protection indication information, and determines that the called UE supports the media stream protection; the calling UE provides at least the self-provided A set of media stream security context information is sent to the called UE, and each set of media stream security context information includes a security algorithm and a corresponding key; A set of all media stream security context information sent by the calling UE is selected, and the selected set of media stream security context information is sent to the calling UE.

That is to say, when the called UE checks the media stream protection indication information, it can be determined that the media stream of the session needs to be protected. If the called UE itself supports media stream protection, the corresponding media stream protection indication information is returned to the calling UE. When the calling UE receives the media stream protection indication information of the called UE, it can be determined that the calling UE supports the media stream protection of the current session. Thereafter, the two parties continue to negotiate to determine a set of media stream security context information, and then use the key to protect the subsequently transmitted media stream.

Here, the called UE selects one set from all the media stream security context information sent by the calling UE, and sends the selected set of media stream security context information between the calling UEs, and the method may further include The called UE uses the new key generated by itself as the key in the selected set of media stream security context information.

That is, although the media stream security context information selected by the called UE is provided by the calling UE, the called UE can also determine the key by itself, but the determined key needs to conform to the selected media stream security context. The rules of the security algorithm can be used.

FIG. 10 is a schematic diagram of a message flow of Embodiment 7 of the method of the present invention. In the seventh embodiment, the first entity is the calling UE, and the second entity is the called UE. The calling or called party can also be a media gateway control function entity/media gateway function entity (MGCF/MGW), and the specific process is similar.

As shown in FIG. 10, the method embodiment 7 includes the following steps:

Step 1001: The calling UE sends an INVITE message to the called UE, where the media stream security protection indication information is used to indicate media that needs media stream security protection, for example, audio 1 and video 2.

During specific implementation, the media stream security protection indication information may be used to indicate the media to be protected by using the security premise described in the IETF draft draft-ietf-mmusic-securityprecondition-04.txt. It is also possible not to use the method of security premise, but the use will be The transport protocol of the media to be protected is set to a method of secure transport protocol, such as setting the media transport protocol to RTP/SAVP. The k=prompt header field in RFC4566 can also be used to indicate media that requires media stream security.

Step 1002: After receiving the session request message, the called UE checks the indication information of the media stream security protection, and determines that it supports the media stream protection. The 183 response message is returned, where the media corresponding to the supported media stream security protection is carried. Media security context information, for example: The called UE only supports video 2, and provides 2 sets of media stream security context information for video 2 (algorithm 1, key 1); (algorithm 2, key 2).

The media stream security context information includes at least a key and a media security algorithm, and may further include a combination of one or both of a key lifetime and a key identifier. The response message may include multiple sets of media stream security context information for the calling UE to select. Each set of media stream security context information herein may be arranged according to priority or each set is added with a corresponding priority indication, indicating that the called UE prioritizes the selection of each set of media stream security context information.

The media security algorithm herein may be one or a combination of an integrity security algorithm or a confidentiality security algorithm. The message used here can also be a 200 response message.

Step 1003: The calling UE sends a PRACK response message to the called UE, where the media stream security context information provided by the local side is carried, for example, ( Algorithm 2, Key 2) in the 183 message is selected.

Here, the calling UE processes the 183 message in two ways. One is that the media stream security context information in the PRACK message is determined by the calling UE according to the media stream security context information provided by the called UE in the 183 message. Media stream security context information. That is, if the called UE provides at least one set of media stream security context information, the calling UE may select and determine a set or a set from all the media stream security context information provided by the called party according to the situation supported by the calling UE. Above, as the media provided by itself to the called UE The security context information is streamed and sent to the called UE using a PRACK message or the like. Thereafter, after receiving the PRACK, the called UE finally determines a set from the media stream security context information in the PRACK message, and sends the 200 message after the PRACK message to the calling UE. Steps 1003 and 1004 describe the situation.

Another processing method is that after the calling UE receives the 183 response, it directly determines the final set of media stream security context information, and sends it to the called UE in the PRACK message, and the called UE sends the PRACK after receiving the PRACK. The media stream security context information does not have to be carried in the 200 response.

In this step, the media stream security context information selected and provided in the PRACK includes at least a key and a corresponding security algorithm, and may further include one or two of a key lifetime and a key identifier. Combination of species. Regardless of the number of media stream security contexts carried in the PRACK, the key in the media stream security context information in the PRACK can be different from the key sent in the called party. For example, instead of using "key 2", the calling party Generate a "key 3" yourself and send it to the called party. Here, the method of using the different keys by the calling party and the called party can refer to the different usage methods of the calling and called keys in RFC4568.

If the calling UE receives the message sent by the called UE as a non-183 message, but a message, the acknowledgement message in this step is an ACK acknowledgement message, and the content carried by the message is similar.

Step 1004: The called UE returns a 200 message corresponding to the PRACK to the calling UE, where the media stream security context information selected by the called UE is negotiated, in this embodiment, (algorithm 2, key 2).

Since both the calling UE and the called UE obtain the corresponding key, the transmitted media stream can be protected by the key.

In this embodiment, the security algorithm may be carried as a crypto-suite parameter in the media stream security description protocol (SDES) defined in RFC4568; Parameters such as key, key identifier, and key validity period can be carried in the key-params parameter in the SDES protocol a =crypto header field. Specifically, the key-method parameter can be used to indicate the carrying method, such as the inline method or Use the key-method-ext extension method. Use the key-info parameter to carry the key and parameters such as key identification and expiration date. The header field of the SDES corresponding to the SRTP protocol can be used as follows: srtp-crypto-suite carries a security algorithm, and srtp-key-method indicates a carrying method, such as an inline method or a method using key-method-ext extension. , srtp-key-info carries the key and parameters such as key identification and expiration date. SDES can carry multiple sets of media stream security context information, that is, it can be carried by using multiple a = crypto header fields. The priority information can be identified according to the order of a = crypto header fields.

In this embodiment, if a multimedia internet key agreement (MIKEY) management protocol is adopted, security contexts such as a security algorithm and a key validity period may be carried in the Security Policy payload field defined in the RFC 3830 MIKEY protocol. In the parameters. The key and the key identifier may be carried in a Key data sub-payload field in a Key Transfer Transport (KEMAC) field in MIKEY. The entire MIKEY message can be carried in the a =key-mgmt SDP attribute field specified in RFC4567. Multiple a =key-mgmt header fields can also carry multiple sets of media stream security context information, and the priority information can be identified according to the order of a =key-mgmt header fields.

11 is a schematic diagram of a message flow according to Embodiment 8 of the method of the present invention, including the following steps: Step 1101: The calling UE sends an INVITE message to the called UE, where the indication information of the media stream security protection is carried, to indicate that the media stream security protection is required. Media, for example: Audio 1 and Video 2.

During specific implementation, the indication of the media stream security protection may indicate the media to be protected by using the security premise method described in the draft draft-ietf-mmusic-securityprecondition-04.txt of the IETF. The usage here is different from the usage in the IETF draft. Here, the INVITE and the subsequent 183 messages do not carry information such as security algorithms and keys. For example, if the SDES protocol is used, the a=crypto:.. header field is not carried, and the security is carried in subsequent PRACK and 200 messages. The information such as the algorithm and the key, correspondingly, the state of the security premise in the INVITE and the subsequent 183 message sent by the calling UE and the called UE is set to the value of the actual state, and the specific value can be set by referring to RFC 3312 and The state setting method in the IETF draft of the security premise, because the INVITE and the subsequent 183 messages do not carry information such as a security algorithm and a key, so the setting method of the security premise in the subsequent PRACK and 200 messages can be adopted. The following methods are used to set: Method 1, the setting method in PRACK still sets the actual state value, and the current state value in 200 is set to the final ^ dog state value, column ^ port, a=curr:sec e2e sendrecv a= Des:sec mandatory e2e sendrecv; Method 2, the current state value in the PRACK and 200 messages is still set to the actual state value, and the subsequent security premise state value uses update and pair The final acknowledgment 200 message set, refer to the specific method of a draft IETF RFC 3312 and the security provided according to. Here, it is also possible to use a method of setting a transmission protocol of the media to be protected as a secure transmission protocol to indicate that the session media stream needs security protection, for example, setting the media transmission protocol to RTP/SAVP. The k=prompt header field in RFC4566 can also be used to indicate media that requires media stream security.

Step 1102: After receiving the INVITE message, the called UE checks the media stream security protection indication information, determines the media that needs to protect the media stream security protection, and returns a 183 response message, which carries the media stream security protection of the local side. The indication information indicates the media supported by the side that requires media stream security protection, for example, video 2.

Different from the seventh embodiment of the method, this step does not directly return the provided media stream security context information to the calling UE, but only informs the calling UE of the information that can support the media stream protection. The method of setting the parameters in the 183 message is similar to the setting method in the INVITE message. Step 1103: The calling UE checks the indication information returned by the called UE, determines that the called UE supports the security protection of the indicated media, and sends a PRACK message to the called UE, where the media stream security context information provided by the local side is carried, for example. : The calling UE provides 2 sets of media stream security context information (algorithm 1, key 1); (algorithm 2, key 2).

The media stream security context information includes at least a key and a media security algorithm, and may further include a combination of one or both of a key lifetime and a key identifier. The PRACK message may include multiple sets of media stream security context information for the called UE to select. Here, the calling UE provides at least one set of media stream context information to the called UE, and each set of media stream security context information may be arranged according to priority or each set is set with a corresponding priority indication, indicating that the calling UE is The priority of the selection of security context information for each set of media streams.

Step 1104: The called UE returns a 200 message corresponding to the PRACK to the calling UE, where the media stream security context information selected by the called UE is carried, which is (Algorithm 2, Key 2) in this embodiment.

The media stream security context information described herein is a set selected by the called UE from at least one set of media stream security context information carried by the PRACK message, and sent to the calling UE in the PRACK 200 message. If the media stream security context information is arranged according to the priority order set in advance or the priority indication indicating the priority order is set, the selection may be performed according to the priority order, that is, the media stream security context information with the highest priority may be selected. .

Of course, the key in the media stream security context information in the 200 message may also be different from the key sent by the called UE in step 1104. For example, instead of using "key 2", the called UE itself generates a "key 3" and sends it to the caller. The main callee uses a different secret The method of using the key can refer to the different usage methods of the calling and called keys in RFC4568.

Thereafter, the calling UE and the called UE continue the subsequent call flow.

In an actual application, the calling UE and the called UE may also use the derived key for encryption and decryption, and after step 1104, the method further includes: the calling UE and the called UE respectively derive a new secret according to the keys of the two parties. The key, and the derived key is used as the key to protect the media stream.

In addition, in this embodiment, the calling UE and the called UE transmit the key through the PRACK message and the 200 message. In practical applications, other messages, such as UPDATE messages and 200 messages, can also be used to transmit keys. In this embodiment, the security algorithm may be carried as a crypto-suite parameter in the a =crypto header field in the Media Stream Security Description Protocol (SDES) defined in RFC4568; the key, the key identifier, and the key validity period. The parameters can be carried in the key-params parameter in the S = crypto header field of the SDES protocol. Specifically, the key-method parameter can be used to indicate the carrying method, such as the inline method or the method using the key-method-ext extension. Use the key-info parameter to carry the key and parameters such as key identification and expiration date. The specific SDES header field corresponding to the SRTP protocol can be used as follows: srtp-crypto-suite carries a security algorithm, srtp-key-method indicates a carrying method, such as inline (inline) method or use key-method-ext extension The method, srtp-key-info carries the key and parameters such as key identification and expiration date. SDES can carry multiple sets of media stream security context information, that is, it can be carried by using multiple a = crypto header fields. The priority information can be identified according to the order of a = crypto header fields. In this embodiment, if a multimedia internet key agreement (MIKEY) management protocol is adopted, The security context of the security algorithm, key validity period, etc. can be carried in the parameters defined in the Security Policy payload field of the RFC 3830 MIKEY protocol. The key and the key identifier may be carried in a Key data sub-payload field in a Key Transfer Transport (KEMAC) field in MIKEY. The entire MIKEY message can be carried in the a =key-mgmt SDP attribute field specified in RFC4567. Multiple sets of media flow security context information can also be carried by using multiple a =key-mgmt header fields. The priority information can be identified according to the order of a =key-mgmt header fields.

The present invention also proposes a corresponding system embodiment for the method for media stream security context negotiation between the calling UE and the called UE.

Figure 12 is a schematic diagram showing the structure of a system embodiment 4 for the method embodiment 2 and the method implementation 6. As shown in Figure 12, the system can include:

The calling UE 1201 sends the media stream security context information including the security algorithm provided by itself to the called UE 1202 through the session request message.

The called UE 1202, the called UE determines the media stream security context information that needs to be provided according to the media stream security context information provided by the calling UE in the session request message, and sends the determined media stream security context information to the calling party through the session response message. UE.

The calling UE 1201 and the called UE 1202 obtain a key according to the media stream security context information provided by the two parties including the security algorithm.

Of course, if the system is applied to different methods, the division of functional modules may be different.

If the system is used in the method embodiment 2, the session request message is an INVITE message, and the session response message is a 183 message, and the media stream security context information provided by the calling UE 1201 through the session request message is at least one set of media stream security context. information. The specific situation of the system can be represented by FIG. 12A. As shown in FIG. 12A, the system implementation fifth may include: The transceiver unit 1201a sends the media stream security context information including the security algorithm provided by itself to the called UE 1202 through the session request message, and sends the generated key to the called UE 1202 by using an acknowledgement PRACK message or an UPDATE message.

Of course, the transceiver unit 1201 may provide at least one set of media stream security context information. In addition, at least one set of media stream security context information provided by the called UE 1202 through the session response message may be received, and the called UE 1202 provides the media stream. The security context is selected according to at least one set of media stream security context information provided by the calling UE 1201. The selecting unit 1201b is configured to select one set of at least one set of media stream security context information provided by the called UE 1202.

The key generating unit 1201c is configured to generate a key according to the security algorithm in the selected media stream security context information.

Accordingly, the called UE 1202 includes:

The transceiver unit 1202a is configured to receive media stream security context information including a security algorithm provided by the calling UE 1201 by using a session request message, and receive a key sent by the calling UE by confirming a PRACK message or an UPDATE message.

The selecting unit 1202b is configured to select at least one set of media stream security upper and lower information supported by the media stream security context information provided by the calling UE 1201, and use the selected at least one set of media stream security context information as the media provided by itself. The security context information is transmitted and sent to the calling UE 1201 through the transceiver unit 1202a.

Further, the called UE 1202 may further include:

The key generating unit 1202c is configured to generate a key according to a security algorithm in the media stream security context information provided by the two parties, and send the key to the calling UE 1201 through the transceiver unit.

Further, the calling UE 1201 may further include:

The derivation unit 1201d derives a new key according to the key generated by the two parties;

Similarly, the called UE1202 may further include: The derivation unit 1202d derives a new key from the keys generated by both parties.

If the system is used in the method embodiment 6, the session request message is an INVITE message, the session response message is a 183 message or a 200 message, and the media stream security context information that the calling UE sends to the called UE includes: The previously generated key generation parameter, the media stream security context information sent by the called UE to the calling UE includes a key generation parameter generated in advance. The specific situation of the system can be represented by FIG. 12B. As shown in FIG. 12B, the calling UE 1201 may include:

The transceiver unit 1201m is configured to send at least one set of media stream security context information provided by itself to the called UE 1202 by using a session request message, where the information in each set of media stream security context includes a security algorithm and a key generation of the calling UE itself. Parameter; receiving a set of media stream security context information provided by the called UE 1202, including a security algorithm and a key generation parameter of the called UE itself.

The key generation unit 1201n generates a key based on the key generation parameter in the media stream security context transmitted by the called UE 1202 and its own key generation parameter.

Accordingly, the called UE 1202 includes:

The transceiver unit 1202m is configured to receive a session request message of the calling UE 1201D, and send the selected media stream security context information to the calling UE 1201 by using a 183 message or a 200 message, where the selected media stream security context information includes a security algorithm and a called The key generation parameters of the UE itself.

The selecting unit 1202r selects a set of media stream security contexts from the plurality of sets of media stream security contexts sent by the calling UE 1201.

The key generation unit 1202n generates a key according to the key generation parameter of the calling UE in the media stream security context selected by the selecting unit 1202r and the key generation parameter of the called UE itself.

13A and 13B are respectively a system structure diagram for the method embodiment VII and the method implementation VIII. Intention. As shown in FIG. 13A, the system may include: a calling UE 1301, and sending a session request message carrying the media stream protection indication information to the called UE 1302 to obtain a media stream including a security algorithm and a key. Security context.

The called UE 1302 receives the session request message carrying the media stream protection indication information, checks the media stream protection indication information, determines that it supports the media stream protection, and obtains the media stream security context including the security algorithm and the key.

In practical applications, if the system is applied to different methods, the functional module division may be different.

The calling UE 1301 includes:

The transceiver unit 1301a is configured to send a session request message carrying the media stream protection indication information to the called UE 1302, receive the 183 message or 200 message of the called UE 1302, and use the selected media stream security context information to pass the PRACK message or the UPDATE message. Send to the called UE1302.

Certainly, the transceiver unit 1301a receives the media stream security context information provided by the called UE 1302, and may be at least one set of media stream security context information, where the media stream security context information includes a security algorithm and a corresponding key.

The selecting unit 1301b selects from all the media stream security context information sent by the called UE 1302.

The called UE1302 may include:

The transceiver unit 1302a is configured to receive a session request message carrying the media stream protection indication information, check the media stream protection indication information, determine that the media stream protection is supported by itself, and pass at least one set of media stream security context information provided by itself to the 183 message or 200. The message is sent to the calling UE 1301, and the media stream security context information includes a security algorithm and a corresponding key. The selected media stream security context information returned by the calling UE 1301 through the PRACK message or the ACK message is received. If the system is applied to determine a set of media stream security context information directly by the calling UE in the method embodiment VII, the media stream security context information selected by the selecting unit 1301b in the calling UE 1301 is a set of media stream security. Contextual information. In this case, a key replacement unit 1301c may be added to the calling UE 1301, and the key in the media stream security context information selected by the selecting unit is replaced by the key generated by the UE itself, and sent. Give the called UE1302.

If the system is applied to the method for determining a set of media stream security upper and lower information by the called UE in the method embodiment 7, the media stream security context information selected by the selecting unit 1301b in the calling UE 1301 is at least one set of media stream security. Context information, the transceiver unit of the called UE is further configured to send a message carrying the media stream protection indication information to the calling UE. The called UE1302 may further include:

The selecting unit 1302b is configured to select one set from at least one set of media stream security context information provided by the calling UE 1301, and send the set to the calling UE 1301 through the transceiver unit.

13B is a schematic structural diagram of a system applied to the eighth embodiment of the method. As shown in FIG. 13B, the calling UE 1301 includes:

The transceiver unit 1301m is configured to send a session request message carrying the media stream protection indication information to the called UE 1302, and receive the media stream protection indication information sent by the called UE by using the 183 message or the 200 message, and determine that the called UE supports the media. The flow protection is configured to send at least one set of media stream security context information provided by itself to the called UE by using a PRACK message or an ACK message, and receive the selected set of media stream security context information sent by the called UE 1302 through the 200 message.

Accordingly, the called UE 1302 includes:

The transceiver unit 1302m is configured to receive a session request message carrying the media stream protection indication information, check the media stream protection indication information, determine that the media stream protection is supported by itself, and send the media stream protection indication information to the host by using the 183 message or the 200 message. Call UE1301; Receiving at least one set of media stream security context information sent by the UE 1301 through a PRACK message or an UPDATE message; sending the selected set of media stream security context information to the calling UE 1301 by using a 200 message, where the media stream security context information includes security Algorithm and corresponding key.

The selecting unit 1302n is configured to select one set from at least one set of media stream security context information provided by the calling UE 1301, and send the set to the calling UE 1301 through the transceiver unit.

In the actual application, the called UE 1302 may further include a key replacement unit 1302r, and replace the key in the media stream security context information selected by the selecting unit 1302n with the key generated by the called UE 1302, and send it to the key. The calling party is UE1302.

The above methods and systems can be applied to systems such as IMS.

It can be seen from the foregoing that the calling UE and the called UE may include a transceiver unit, a key generation unit, a selection unit, a derivative unit, and the like. How are the units combined, and what is the function thereof, and the specific Method or system related.

For example, the calling UE in the second embodiment of the method is used as an example. If the calling UE can derive a new key according to the generated key and the generated key of the called UE, the calling UE may include a transceiver unit. The selection unit, the key generation unit, the derivative unit, and the functions and connection relationships of the respective units may correspond to the respective units in the UE 1201 in FIG. 12A. Of course, if the calling UE is called by another UE, it should also have the function of the called UE 1202, and details are not described herein again.

For example, in the sixth embodiment of the method, if the calling UE can generate a key according to its own key generation parameter and the key generation parameter of the called UE, the calling UE can include the transceiver unit and the key. The unit is generated, and the situation corresponds to each unit in the UE 1201 in FIG. 12B, and details are not described herein again.

For example, in the seventh embodiment of the method, if only the calling UE sends the media stream protection indication information, the calling UE may include a transceiver unit, a selection unit, and a key replacement. The unit corresponds to each unit in the UE 1301 in FIG. 13A, and details are not described herein again. In summary, the present invention also proposes an apparatus for implementing media stream security context negotiation, and the internal structure diagram thereof is different according to the implementation manner thereof, and the internal structure diagram of the UE in FIG. 12, FIG. 12A, FIG. 12B, FIG. 13A, and FIG. 13B may be respectively used. Indicates that it will not be described here.

Applying the solution of the embodiment of the present invention, since the UE does not need to perform complicated calculation, and does not need the public key facility in the network, the calling UE and the called UE directly interact to obtain the security algorithm and the key. The media stream security context information, thereby implementing media stream security context negotiation in the IMS system, and facilitating subsequent media stream security protection in the IMS network.

In conclusion, the above is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications, equivalents, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

The method according to claim 1, wherein the session request message is an invite INVITE message, and the session response message is a 183 message or a 200 message, and the media stream provided by the calling UE through the session request message The security context information is at least one set of media stream security context information;

The method for the called UE to determine the security context information of the media stream is: the called UE selects at least one set of media stream security upper and lower information supported by the media stream security context information provided by the calling UE, At least one set of media stream security context information is selected as the media stream security context information provided by itself.

The method according to claim 2, wherein the step of obtaining the key by the calling UE and the called UE according to the media stream security context information of the security algorithm provided by the two parties includes:

The calling UE selects a set of at least one set of media stream security context information provided by the called UE, and carries the generated key to the selected media stream security context information, and confirms the PRACK message or UPDATE. A message is sent to the called UE.

The method according to claim 3, wherein, after the calling UE sends the generated key to the called UE by using an acknowledge PRACK message or an UPDATE message, the method further includes:

The called UE generates a key and sends the message to the calling UE through a 200 message.

The method according to claim 4, after the called UE sends the generated key to the calling UE by using a 200 message, the method further includes: the calling UE and the called party The UE derives a new key based on the keys generated by both parties.

The method according to claim 1, wherein the media stream security context information sent by the calling UE to the called UE further includes a key generation parameter of the calling UE itself; The media stream security context information also includes a key generation parameter of the called UE itself;

The method for obtaining the key by the calling UE and the called UE according to the media stream security context information of the security algorithm provided by the two parties is: the key generation in the media stream security context provided by the calling UE according to the called UE The parameter and its own key generation parameter generate a key, and the calling UE generates a key according to the key generation parameter in the media stream security context provided by the called UE and its own key generation parameter.

The method according to claim 6, wherein the session request message is an INVITE message, and the session response message is a 183 or 200 message.

The method according to claim 1, wherein the session request message is an INVITE message, and the session response message is a 183 or 200 message, and the media stream security context sent by the calling UE to the called UE The information is at least one set of media stream security context information, and each set of media stream security context information further includes a key generation parameter;

The method for the called UE to determine the security context information of the media stream provided by the UE is: selecting a set supported by the media stream security context information provided by the calling UE, and generating a parameter of the key. As selected media stream security context information

The method according to claim 8, wherein the step of obtaining the key by the calling UE and the called UE according to the media stream security context information of the security algorithm provided by the two parties includes:

The called UE generates a key according to the key generation parameter in the selected media stream security context and its own key generation parameter, and the calling UE generates the key according to the key in the media stream security context sent by the called UE. The parameter and its own key generation parameters generate a key.

10. A method for implementing media stream security context negotiation, the method comprising:

UE;

The method according to claim 10, wherein the step of the called UE and the calling UE obtaining the media stream security context information including the security algorithm and the key comprises: the called UE providing the self-provided At least one set of media stream security context information is sent to the calling UE, where the media stream security context information includes a security algorithm and a corresponding key; the calling UE directly directly from the media stream security context information sent by the called UE A set is selected, and a selected set of media stream security context information is sent to the called UE.

The method according to claim 11, wherein the session request message is an INVITE message;

The called UE sends at least one set of media stream security context information provided by itself to the calling UE by using a 183 message or a 200 message; The calling UE sends the selected set of media stream security context information to the called UE by using a PRACK message or an ACK message.

The method according to claim 11, wherein the calling UE selects one set of all media stream security context information sent by the called UE, and selects a set of media stream security contexts. The information is sent between the called UEs, and the method further includes:

The calling UE uses the new key generated by itself as the key in the selected set of media stream security contexts.

The method according to claim 10, wherein the step of the called UE and the calling UE obtaining the media stream security context information including the security algorithm and the key comprises: the called UE providing the self-provided At least one set of media stream security context information is sent to the calling UE, the media stream security context information includes a security algorithm and a corresponding key; the calling UE selects from all media stream security context information provided by the called UE At least one set of media stream security upper and lower information supported by itself, and sending at least one set of media stream security context information to the called UE;

The called UE selects one set from at least one set of media stream security context information provided by the calling UE, and sends the set to the calling UE.

The method according to claim 14, wherein the request message is an INVITE message;

The called UE sends at least one set of media stream security context information provided by itself to the calling UE by using a 183 message or a 200 message;

The calling UE sends the selected at least one set of media stream security context information to the called UE by using a PRACK message or an UPDATE message;

The called UE sends a selected set of media stream security context information to the calling UE through a 200 message.

The method according to claim 10, wherein the step of the called UE and the calling UE obtaining the media stream security context information including the security algorithm and the key comprises: the called UE protecting the media stream Instructing information is returned to the calling UE;

The calling UE checks media stream protection indication information, and determines that the called UE supports media stream protection;

The calling UE sends at least one set of media stream security context information provided by the calling UE to the called UE, where the media stream security context information includes a security algorithm and a corresponding key; the called UE sends the message from the calling UE. A set of all media stream security context information is selected, and a selected set of media stream security context information is sent to the calling UE.

The method according to claim 16, wherein the session request message is an INVITE message;

The called UE returns the media stream protection indication information to the calling UE by using a 183 message or a 200 message;

The calling UE sends at least one set of media stream security context information provided by itself to the called UE by using a PRACK message or an UPDATE message;

The called UE sends the selected set of media stream security context information to the calling UE through the 200 message.

The method according to claim 16, wherein the called UE selects one set of all media stream security context information sent by the calling UE, and selects a set of media stream security contexts. The information is sent between the calling UEs, and the method further includes:

The called UE uses the new key generated by itself as a key in the selected set of media stream security context information.

The method according to any one of claims 10 to 18, wherein the media stream protection indication information is a media stream protection indication set by a method using a security premise. The information, or the media stream protection indication information obtained by setting the transmission protocol corresponding to the media to the secure transmission protocol, or the media stream protection indication information by using the value in the k header field in the SCP protocol.

20. A system for implementing media stream security context negotiation, the system comprising:

The called UE, the called UE determines the media stream security context information that needs to be provided according to the media stream security context information provided by the calling UE in the session request message, and sends the determined media stream security context information to the calling party through the session response message. UE;

The calling UE and the called UE obtain a key according to the media stream security context information provided by the two parties including the security algorithm.

The system according to claim 20, wherein the session request message is an INVITE message, the session response message is a 183 message or a 200 message, and the mediation flow provided by the calling UE through the session request message is secure. The context information is at least one set of media stream security context information; the called UE includes:

a transceiver unit, configured to receive media stream security context information including a security algorithm provided by the calling UE through the session request message; and receive a key that is sent by the calling UE by confirming the PRACK message or the UPDATE message;

a selecting unit, configured to select at least one set of media stream security upper and lower information supported by the media stream security context information provided by the calling UE, and select at least one set of media stream security context information as the media stream provided by itself Security context information, and sent to the calling UE through the transceiver unit;

The calling UE includes:

Transceiver unit, the media stream including the security algorithm provided by itself through the session request message The security context information is sent to the called UE, and the generated key is sent to the called UE by using an acknowledge PRACK message or an UPDATE message;

a selecting unit, configured to select one set from at least one set of media stream security context information provided by the called UE;

And a key generating unit, configured to generate a key according to the security algorithm in the selected media stream security context information.

The system according to claim 21, wherein the called UE further comprises:

The key generation unit is configured to generate a key according to a security algorithm in the media stream security context information provided by the two parties, and send the key to the calling UE through the transceiver unit.

The system according to claim 22, wherein the calling UE further comprises:

a derivative unit that derives a new key based on a key generated by both parties;

The called UE further includes:

The derivative unit derives a new key based on the keys generated by both parties.

The system according to claim 20, wherein the session request message is an INVITE message, and the session response message is a 183 message or a 200 message;

The calling UE includes:

a transceiver unit, configured to send at least one set of media stream security context information provided by the session request message to the called UE by using a session request message, where the information in each set of media stream security context includes a security algorithm and a key generation parameter of the calling UE itself Receiving a set of media stream security context information provided by the called UE, including the security algorithm and the key generation parameter of the called UE itself; the key generation unit, according to the key generation parameter in the media stream security context sent by the called UE Generating a key with its own key generation parameters;

The called UE includes: The transceiver unit is configured to receive a session request message of the calling UE, and send the selected media stream security context information to the calling UE by using a 183 message or a 200 message, where the selected media stream security context information includes a security algorithm and a called UE. Its own key generation parameters;

The selecting unit selects one set from at least one set of media stream security contexts sent by the calling UE;

The key generation unit generates a key according to the key generation parameter of the calling UE in the media stream security context selected by the selecting unit and the key generation parameter of the called UE itself.

25. A system for implementing media stream security context negotiation, the system comprising:

The system according to claim 25, wherein the session request message is an INVITE message, and the called UE includes:

The transceiver unit is configured to receive a session request message carrying the media stream protection indication information, check the media stream protection indication information, determine that the media stream protection is supported by itself, and pass at least one set of media stream security context information provided by itself to the 183 message or the 200 message. Sending to the calling UE, the media stream security context information includes a security algorithm and a corresponding key; and receiving the selected media stream security context information returned by the calling UE by using a PRACK message or an UPDATE message.

The system according to claim 26, wherein the calling UE comprises: a transceiver unit, configured to send a session request message carrying the media stream protection indication information to the called UE; and receive the called UE 183 messages or 200 messages, will select the media stream The full context information is sent to the called UE through a PRACK message or an UPDATE message;

The selecting unit selects from all the media stream security context information sent by the called UE.

The system according to claim 26, wherein the media stream security context information selected by the selecting unit in the calling UE is a set of media stream security context information.

The system according to claim 27, wherein the media stream security context information selected by the selecting unit in the calling UE is at least one set of media stream security context information, and the called UE transceiver unit Further, the method further includes: sending, to the calling UE, a message that carries the media stream protection indication information, where the called UE further includes:

And a selecting unit, configured to select one set from at least one set of media stream security context information provided by the calling UE, and send the set to the calling UE by using the sending and receiving unit.

The system according to claim 25, wherein the session request message is an INVITE message, and the calling UE includes:

The transceiver unit is configured to send a session request message carrying the media stream protection indication information to the called UE, and receive the media stream protection indication information sent by the called UE by using the 183 message or the 200 message, and determine that the called UE supports the media stream. Protecting; transmitting at least one set of media stream security context information provided by itself to the called UE by using a PRACK message or an UPDATE message, and receiving the selected set of media stream security context information sent by the called UE through the 200 message;

The called UE includes:

The transceiver unit is configured to receive a session request message carrying the media stream protection indication information, check the media stream protection indication information, determine that the media stream protection is supported by itself, and send the media stream protection indication information to the calling party by using the 183 message or the 200 message. UE: receiving at least one set of media stream security context messages sent by the calling UE through a PRACK message or an UPDATE message Sending a selected set of media stream security context information to the calling UE by using a 200 message, where the media stream security context information includes a security algorithm and a corresponding key;

31. An apparatus for implementing a security context negotiation of a media stream, where the apparatus is a calling UE, and includes:

The device according to claim 31, wherein the transceiver unit is further configured to receive a key sent by the called UE;

The device further includes:

The deriving unit derives a new key according to the key generated by the key generating unit and the key sent by the called UE.

33. An apparatus for implementing media stream security context negotiation, where the apparatus is a calling UE, and includes:

The transceiver unit sends at least one set of media stream security context information that is provided to the called UE by using a session request message, where each set of media stream security context information includes a security algorithm And a key generation parameter of the calling UE itself; receiving a set of media stream security context information provided by the called UE through the session response message, where the key generation parameter in the set of media stream security context provided by the called UE is Call the UE's own key generation parameters;

The key generation unit generates a key according to the key generation parameter of the calling UE itself and the key generation parameter of the called UE.

34. An apparatus for implementing a media stream security context negotiation, where the apparatus is a calling UE, and includes:

The transceiver unit sends a session request message carrying the media stream protection indication information to the called UE, and receives at least one set of media stream security context information provided by the called UE through the session response message, where the media stream security context information includes a security algorithm. And the corresponding key; sending the media stream security context information selected by the selecting unit to the called party;

The selection unit selects from all media stream security context information provided by the called UE.

The device according to claim 34, wherein the media stream security context information selected by the selecting unit is a set of media stream security context information, and the device further comprises:

The key replacement unit replaces the key in the media stream security context information selected by the selecting unit with the key generated by the calling UE itself.

The device according to claim 33, wherein the media stream security context information selected by the selecting unit is at least one set of media stream security context information;

The transceiver unit is further configured to: receive a message that is sent by the called UE and carry the media stream protection indication information, and receive the selected set of media stream security context information sent by the called UE;

The device further includes:

a key replacement unit, in a set of media stream security context information sent by the called UE The key is replaced by the key generated by the UE itself and sent to the called UE through the transceiver unit.