CN101557603B

CN101557603B - Method, device and system for lawful monitoring

Info

Publication number: CN101557603B
Application number: CN2009101404529A
Authority: CN
Inventors: 邵钢锤
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2009-05-15
Filing date: 2009-05-15
Publication date: 2011-04-20
Anticipated expiration: 2029-05-15
Also published as: CN101557603A

Abstract

The embodiment of the invention discloses a method, device and system for lawful interception. The realization of the method is as follows: receiving a call establishment request related to the monitored user; determining whether the current call is an H.324 video call; if it is an H.324 video call, then interacting with the SBC to establish a transmission link, and the SBC Interact with the RTSP server in the monitoring center to establish a transmission link; after receiving the H.324 video data, send the H.324 video data to the SBC through the established transmission link, and the SBC completes the H.324 data to RTSP Data format conversion, the converted data is sent to the monitoring center through the transmission link between the SBC and the RTSP server of the monitoring center MC. By converting the video media at the border session controller and sending it to the monitoring device, video monitoring is realized, and the MC can realize video monitoring without upgrading.

Description

A kind of methods, devices and systems of Lawful Interception

Technical field

The present invention relates to communication technical field, particularly a kind of methods, devices and systems of Lawful Interception.

Background technology

Lawful Interception is meant the monitoring that utilizes special equipment that the specific communications user is carried out at law within the scope of authority.The content of Lawful Interception output comprises: Content of communciation (Content of Communication) and the information (Intercept Related Information) relevant with calling.

In existing Lawful Interception, the Lawful Interception function externally realizes 3 interfaces: submit interface 1 (Handover Interface 1 to, HI1) data management (Administration Function, ADMF) interface, HI2 Intercept related information (Interception Related Information, IRI) reporting interface, HI3 Content of communciation (Call Content, CC) reporting interface.

The HI1 data management interface is mainly realized legal monitoring device, and (Law Enforcement MonitoringFacility is LEMF) to network element setting, cancellation, modification, the order of inquiry intercept target and return command result.When different local specific implementations, the HI1 interface may be a manual interface or electrical interface.

HI2 Intercept related information reporting interface realizes that mainly network element reports the relevant information of the critical event of intercept target to LEMF.When taking place such as registration, critical events such as call setup, called party answer, conversation end, new business realization in the session control, network element reports the station address information, current time of the station address information of intercept target, relevant participant and other with professional relevant information etc. by this interface.

HI3 Content of communciation reporting interface realizes that mainly network element reports intercept target Content of communciation in conversation procedure to LEMF, such as voice, video, data traffic information etc.

Wherein the function of X1, X2, X3 interface is distinguished the function of corresponding HI1, HI2, HI3 interface.The X1/X2 interface can be connected realization by IP with the HI1/HI2 interface, in networking, can use Lawful interception gateway (Lawful Interception Gateway, LIG) realize of the conversion of X1/X2 interface, realize the duplicating of network element monitor report simultaneously, transmit, function such as filtration to the HI1/HI2 interface.

As shown in Figure 1, be the system schematic of prior art at the processing video monitor; This programme is (the Mobile Switching Center of mobile switching centre 202, MSC) adopt ISUP (Integrated Service Digital Network User Part, ISUP), call control protocol (Bearer Independent Call Control Protocol with bearer independent, BICC), session initiation protocol (Session Initiation Protocol, SIP) etc. signaling is at Universal Media Gateway 201 (Universal MediaGateway, UMG) with listening center 204 (Montor Center, MC) connect between, Universal Media Gateway 201 sends to listening center 204 to the code stream of form H.324M with the form of CC.After MC received this code stream, the MC basis H.324M H.245 control protocol of protocol stack parsed video and audio frequency.Dotted line is connected to the signaling connection among Fig. 1, and solid line is connected to data and connects, and subsequent embodiment also adopts this plotting mode, explanation no longer one by one; MC and streaming media server need support to receive the 3G-324M video in this scheme.H.248 mobile switching centre 202 can adopt with Universal Media Gateway 201 that signaling communicates, and mobile switching centre 202 establishes a communications link by X1 and X2 interface with Lawful interception gateway 203; Lawful interception gateway 203 connects with H1 and H2 interface with listening center 204; Universal Media Gateway 201 is H3 with the communication connection interface of listening center 204.

Above-mentioned video monitor scheme needs MC to support H.324M form, yet a lot of MC do not support H.324M form in the existing network, cause video monitor to realize.

Summary of the invention

The technical problem that the embodiment of the invention will solve provides a kind of methods, devices and systems of Lawful Interception, realizes video monitor.

For solving the problems of the technologies described above, the method embodiment of Lawful Interception provided by the present invention can be achieved through the following technical solutions:

Receive the setup requests relevant with intercepted user;

Determine that whether current calling is video call H.324;

If video call H.324 then carries out Signalling exchange with boarder controller SBC, set up transmission link, the agreement RTSP server that spreads in real time of SBC and listening center carries out Signalling exchange, sets up transmission link;

After receiving H.324 video data, to H.324 by the transmission link of setting up, video data is sent to SBC, finishing H.324 by SBC, data send to listening center with the data after the conversion by the transmission link between the RTSP server of SBC and listening center MC to the format conversion of RTSP data.

The embodiment of the invention also provides a kind of mobile switching centre, comprising:

The call request receiving element is used to receive the setup requests relevant with intercepted user;

The type of call determining unit is used for determining that whether current calling is video call H.324;

The link establishment unit is used for setting up transmission link if video call H.324 then carries out Signalling exchange with boarder controller SBC;

The video data receiving element is used to receive H.324 video data;

Video data sends the unit, after being used to receive H.324 video data, to H.324 by the transmission link of setting up, video data is sent to SBC, finishing H.324 by SBC, data send to listening center with the data after the conversion by the transmission link between the RTSP server of SBC and listening center MC to the format conversion of RTSP data.

The embodiment of the invention also provides a kind of system of Lawful Interception, comprising:

Mobile switching centre is used to receive the setup requests relevant with intercepted user; Determine that whether current calling is video call H.324; If video call H.324 then carries out Signalling exchange with SBC, set up transmission link; After receiving H.324 video data, by the transmission link set up H.324 video data be sent to SBC;

Boarder controller is used for carrying out Signalling exchange with the RTSP server of listening center, sets up transmission link; After receiving described H.324 video data, finish the format conversion of data H.324 to the RTSP data, with the data after the conversion by and the RTSP server of MC between transmission link send to MC.

Technique scheme has following beneficial effect: by video media being changed and sent to audiomonitor at the border conversation controller, realized video monitoring, MC need not upgrade, and can realize video monitor.

Description of drawings

In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art, to do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below, apparently, accompanying drawing in describing below only is some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 is the system configuration schematic diagram of Lawful Interception in the prior art;

Fig. 2 is the embodiment of the invention one a method flow schematic diagram;

Fig. 3 is the embodiment of the invention two networking schematic diagrames;

Fig. 4 is an embodiment of the invention method flow networking schematic diagram;

Fig. 5 is the embodiment of the invention two another networking schematic diagrames;

Fig. 6 is the embodiment of the invention three networking schematic diagrames;

Fig. 7 is the embodiment of the invention three method schematic flow sheets;

Fig. 8 is an embodiment of the invention four directions method schematic flow sheet;

Fig. 9 is the embodiment of the invention five apparatus structure schematic diagrames;

Figure 10 is the embodiment of the invention five another apparatus structure schematic diagrames;

Figure 11 is the embodiment of the invention five an apparatus structure schematic diagram again;

Figure 12 is the embodiment of the invention six system configuration schematic diagrames.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the invention, the technical scheme in the embodiment of the invention is clearly and completely described, obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills belong to the scope of protection of the invention not making the every other embodiment that is obtained under the creative work prerequisite.

Embodiment one, and as shown in Figure 2, the method for a kind of Lawful Interception that the embodiment of the invention provides can comprise:

Step 301: receive the setup requests relevant with intercepted user;

Step 302: determine that whether current calling is video call H.324;

Step 303: if video call H.324, then (Session BorderController SBC) carries out Signalling exchange, sets up transmission link, and the RTSP server of SBC and listening center carries out Signalling exchange, sets up transmission link with boarder controller;

Step 304: after receiving H.324 video data, to H.324 by the transmission link of setting up, video data is sent to SBC, finishing H.324 by SBC, data send to listening center with the data after the conversion by the transmission link between the RTSP server of SBC and MC to the format conversion of RTSP data.

In addition, step 302 determines it is not video call H.324, then the media data of current calling can be sent to MC.Above-mentioned is not video call H.324, can be the various callings of other type, for example can this embodiment of the invention not limited for RTSP Media Stream, voice medium etc.

The executive agent of above-mentioned each step of execution mode can be (the Mobile SwitchingCenter of mobile switching centre, MSC), by video media being changed and is sent to audiomonitor at the border conversation controller, realized video monitoring, MC need not upgrade, and can realize video monitor.

Such scheme also has following beneficial effect at least:

(1) networking efficient:

Video image generator (Video Image Generator, VIG) as Video Interworking Gateway, be built in media gateway (Media Gateway at present, MGW) in, can realize third generation digital communication (3rd Generation, 3G) the video interconnection of (as 3G and SIP video terminal) between video terminal and other video terminal or system, speech channel and the signaling that can avoid simultaneously using external VIG to exist are made a circulation, can simplify network configuration, be convenient to simultaneously realize the flexible deployment of video traffic and carry out.Present embodiment is based upon and proposes on the built-in VIG scheme basis, can be understood as that H.324M switch can be exported, (Real-time Protocol, RTP), so this scheme efficient from the networking is to have improved to RTP.

On the other hand, originally (IP Multimedia Subsystem IMS) just possesses the Lawful Interception function to SBC in the network, this patent uses the new monitoring node of SBC introducing useless, also is to have promoted from networking efficient in the IP multimedia system.

(2) monitor networking security:

SBC is at third generation partner program version 6 (3rd Generation Partnership Project R6,3GPP R6) definition is coordination and the modification of finishing signaling and Media Stream in the network configuration, finish network address translation (Network Address Translation, NAT)/fire compartment wall (FireWal, FW) pass through, application layer antimagnetic disc operating system (DOS) attacks, etc. safety guarantee, thereby make the networking of monitoring safer, (Network Element is NE) and between the MC because SBC is between network element.This function of SBC is particularly outstanding than VIG.

(3) topology hiding effect:

Session Initiation Protocol is to come route by the address of service-route or Via record, finishes the signaling transmission between the calling and called thus, finishes the control stage of call setup; Write down the initial address and request (Request) universal resource identifier (the UniformResource Identifier of this sip message by coming contact address (Contact), URI) write down called address, if SBC replaces to the IP address of these several message headers the IP address of oneself as required when receiving each sip message so, the address of just having only SBC seen of its both sides so, all think oneself communication to as if SBC, embody the effect of topology hiding completely.

Embodiment two and embodiment three will be respectively just monitored terminal by the Lawful interception gateway setting or by terminal these two kinds of scenes are set embodiment one is described further.

Carry out briefly introducing H.324M protocol stack earlier before the explanation of embodiment two and embodiment three, H.324M as shown in table 1:

Table 1

H.245 be H.323 to be used for the agreement that media channel is controlled in the protocol suite, mainly finish the foundation of each logical channel in the multimedia communication and safeguard and release.The controlled function such as capability negotiation that specifically comprise the opening and closing parameter setting receiving-transmitting sides of logical channel, it also will finish the cooperation controlled function of logic channel in the multipoint conference calling simultaneously, H.245 control signal transmits on a control channel that connects based on TCP, must go ahead of the rest before any logic channel foundation and discharging behind sign off of control channel.

H.223 be the multiplex protocol of low bit rate multimedia communication, can be used between two low bit rate multimedia terminals, or between low bit rate multimedia terminal and multipoint control unit or the interactive operation adapter.Agreement allows digital voice/audio frequency, digital video/image and the data message of transmission combination in any on the single-channel communication link.H.223 agreement is cut apart by use and is ressembled and provide low delay and low expense by the information that makes up from the Different Logic channel in single packets of information.For realizing the necessary control procedure of this multiplex protocol regulation in suggestion H.245.

H.263 be on band-limited channel delivery quality preferably its application target of video coding agreement of video image be based on public switched telephone network (Public Switched Telephone Network, the video transmission in video telephone PSTN) (Videophone) and video conferencing (Conference Television) and the radio communication.

(Audio/Modem Riser is the open industrial standard of a cover AMR), and the expansion card of its definition can be supported sound and Modem function simultaneously for sound, modulator-demodulator plug-in card.Adopt this technology can solve some restrictions on function behind integrated sound of mainboard and the Modem subsystem.

Embodiment two, as shown in Figure 3, this programme utilizes IP Multimedia System (IP MultimediaSubsystem, IMS) SBC in the network (404) (is also referred to as soft switch sometimes, as MsoftX3000 etc.) handle form H.324M, video is converted to the video of the procotol form of real-time streaming transmission, and the video after will changing sends to media server 408, the staff can directly play the monitoring video at the media client 409 of media server in real time.The procotol of above-mentioned real-time streaming transmission can for the agreement of spreading in real time (Realtime Streaming Protocol, RTSP) or Microsoft's media services agreement (Microsoft Media Server, MMS);

Fig. 3 is WCDMA mobile communication system (Wideband Code Division MultipleAccess WCDMA), circuit domain (Circuit Switch, CS) framework of network and the shared audiomonitor of IMS network.MsoftX3000 and UMG are for being circuit domain equipment.Mobile switching centre 402 can connect by the BICC/ISUP/DSS/SIP signaling with border conversation controller 404 in addition; Adopt the X3 interface to be connected the video that can be used for transmitting the 3G-324 form between Universal Media Gateway 401 and the boarder controller 404; Strategy decisive function 405 (Policy Decision Function, PDF), Proxy Call Session Control Function (Procuration Call Server Control Function, P-CSCF), service call conversation control function (Service Call Server Control Function, S-CSCF), P-CSCF can judge that a session need be monitored and need be provided Media Stream to the monitor board, can also pass through PDF (405) control SBC (404) duplicate media stream to LIG (403) or LEMF;

The function declaration that capital equipment can have in the said system:

RTSP Server (being a kind of media stream server 408)

The RTSP media stream server provides real-time broadband video-on-demand, support activities motion picture expert group version 4 (Moving Picture Experts Group4, MPEG4) and third generation partner program (3rdGeneration Partnership Project, 3GPP) multimedia standardization.This server usually can the receiving terminal request, reads media file from memory device, sends to the player of the network terminal; Accept the program request terminal time-out, F.F., rewind down, request such as drag, stop, and the media file of playing being controlled according to terminal request; Can broadcast to all long-range or local terminals the video of having stored.And can support the concurrent session about 2000.

Client

The media client support will belong to the listing of video monitor of this MC, and the media data that sends to RTSP Server after the SBC conversion all can be shown on the client, so that the staff checks at any time.Client is supported functions such as real-time video request program, playback and time-out simultaneously.

SBC

Session Border Controller (Session Border Controller, SBC) at Internet protocol (InternetProtocol, IP) network boundary is controlled the session that real-time voice, video and other data are constituted, realize network security, service quality (Quality of Service, QoS) (Network Address Translation NAT) function such as passes through for control, network address translation.Huawei meeting engine (QuidwaySessionEngine2300) is the Session Border Controller of Huawei Company's independent research, it in the IMS of Huawei Company solution, can provide Core Border Gateway Function (Core Border Gateway Function, C-BGF).SE2300 can provide business support neatly in multiple network is used, SE2300 both can only be the medium agency, can do Xin Lingdaili simultaneously again, perhaps when being the medium agency signaling is NAT and handles.SE2300 has C-BGF, I-BGF, I-BCF, miscellaneous service functional interface (IWF) function in IMS, both can be used as customer access equipment, can be used as network interworking equipment again.SE2300 both can be used for IMS and the H.323 intercommunication of network as IWF equipment the time, can be used for the signalling interworking of IMS and RTSP network again.SE2300 be applicable to the IP agreement version number 4 (Internet Protocol version4, IPv4), the IPv6 mixed networking uses.In network layer, SE2300 supports NAT-PT; In application layer, SE2300 supports based on the sip message of IPv4 and based on the conversion between the sip message of IPv6.Simultaneously, (Virtual Router Redundancy Protocol, VRRP) agreement are formed a backup group by main (Master) equipment and some backups (Backup) equipment to SE2300 virtual support router redundance protocol.Under the normal condition, Master device processes business, Backup equipment is in listening state; When the Master device fails, the Backup equipment that priority is high will be taken over job as new Master equipment.

The agreement of supporting on internal interface and the interface in the said system is as shown in table 2:

Table 2 internal interface is described

Interface	Physical interface is described	Signaling interface is described
			Interface between HI3_1:MSC and the SBC	1000 base T Ethernet or E1 (2048kbit/s) G.704	SIP_I, ISUP, BICC or PRI (ISDN DSS1)
Interface between HI3_2:SBC and the Streaming server	1000?base?T?Ethernet	RTSP?Protocol?(IETFRFC2326)
			Interface between HI_3:StreamingServer and the Client	1000?base?T?Ethernet	RTSP Protocol or HTTP protocol

In the HI_1 passage, Intercept related information can partly carry at the ISUP of SIP_I in Session Initiation Protocol family, and ISUP can carry the relevant information of monitoring in the subaddressing.(the definition reference of subaddressing is agreement Q.931)

System shown in Figure 3 realizes that the mode of Lawful Interception can be with reference to shown in Figure 4, and the application background of the flow process hypothesis among Fig. 4 is: portable terminal (Mobile) A has been arranged to eavesdropping target (Target) by LIG at MSC; The signaling of MSC interoffice support is the SIP signaling; Support SIP signaling (the SIP here can use SIP_I, and SIP-ITU-T has offered some clarification on the parameter maps of SIP and ISUP, can carry the monitoring parameter in the subaddressing, also can adopt ISUP, PRA, BICC signaling certainly if desired) between MSC and the SBC;

501) terminal A calling terminal B, in being set, (setup) message can carry following information, public land mobile network office authenticates (Public Land Mobile Network board certified PLMNBC) can be information technology and communication industry (Information Technologe andCommunication, ITC)=unified display interface (Unified Display Interface, UDI), need fixed network user rate (FNUR)=64kbit/s, the and of registration center (RA)=H.223 H.245, (Transparent) that CE=is transparent.Represent that this calling is a H.324M video call; Mobile switching centre returns to Lawful interception gateway and calls out dependent event notice (CALL RELATED EVENTNOTIFICATION) expression calling beginning (Call initiating) then;

502) boarder controller and mobile switching centre consult the transmission parameter of video media; Negotiations process can be invited (INVITE) message for: mobile switching centre sends to boarder controller, and (Session Description Protocol SDP) indicates the transmission parameter of self supporting to carry Session Description Protocol; Boarder controller returns the result of negotiation and returns and ask successfully (200OK) message, mobile switching centre returns affirmation (ACK) message then, determine the transmission parameter of video media, can be when boarder controller sends video in mobile switching centre with reference to the video media transmission parameter of consulting here.Mobile switching centre and boarder controller connect and realize conversation (Conversation) then;

502) mobile switching centre and terminal B consult the transmission parameter of video media afterwards; Answer before this calls out at terminal B, MSC can judge whether this is that a video monitor is called out, in step 501, receive setup requests after MSC can set up link by SIP signaling and SBC, for transmitting follow-up H.324M data.(be the direct signaling point between Msoft3000 and the SBC among Fig. 3, can certainly adopt UMG) as the pass-through signaling point; After setting up link by the terminal B of SIP signaling and his office, begin the video parameter that terminal A and terminal B consult is passed to SBC by the link that MSC and SBC have consulted, the video data of terminal A and terminal B also passes to SBC from this passage.

Concrete process and 402 of consulting) similar; Mobile switching centre can send ring (ALERTING) message to terminal A after terminal B returns negotiation result; After negotiation was finished, mobile switching centre connect net (CONNECT) and sets up being connected of mobile switching centre and terminal A; Call out dependent event notice (CHNCONTROL EVENT NOTIFICATION) expression call setup (Channelestablishing).

503) border conversation controller and mobile switching centre carry out H.245 parameter negotiation; The process of consulting comprises: the principal and subordinate judges that (master-slave determination MSD), opens logical channel (OpenLogical Channel, OLC), telecommunication system (Tele Communication Systems, TCS) capabilities exchange request, multiplexing transmission request.

504) SBC and media server such as RTSP server are to the negotiation of video media transmission parameter; Concrete negotiations process can for: SBC sends announcement (ANNOUNCE) message to media server and carries media description (media description); Media server returns request success message (200OK) can also return the transport-type that option (Options) inquiry is supported, for example whether support the communications industry standard agreement video format (Third Generation Partnership Project file format, 3GP); SBC returns 200OK message to media server, and media server is to the setup message sets audio transmission parameter of SBC transmission audio frequency, and SBC returns 200OK message; Media server is to the setup message sets video transmission parameter of SBC transmission video, and SBC returns 200OK message; Media server sends to SBC and writes down (Record) message automatically, the result that indication SBC record is consulted, and SBC returns 200 OK message; SBC can transmit video to media server according to above-mentioned negotiation parameter then.

After SBC receives the H.324M code stream of mobile switching centre's transmission, resolve according to protocol stack H.324M, wherein the format parameter of video can obtain from the H.245 negotiation information of terminal A and terminal B, SBC finishes the conversion of H.324M arriving the RTSP form afterwards, the announcement (ANNOUNCE) by user end to server, (Setup) is set, record operations such as (Record) sends to media server with medium.

505) parameter negotiation of Client before media server request medium; The process of consulting can be provided with message the video transmission parameter is set for: Client sends to media server; Client can send to media server and broadcast request message, and after media server returned 200 OK message, media server can be to the real-time displaying video stream of Client; Client can also send to media server and suspend request, and media server returns 200OK message and suspends the transmission of video.

Subsequent step is that terminal A and terminal B finish the flow process that video is connected, is general process ends, specific implementation can for: terminal B sends goodbye (BYE) message request to mobile switching centre and disconnects the medium connection; Mobile switching centre returns 200OK message; Mobile switching centre and SBC close logical channel by H.245 realizing end session command; Mobile switching centre sends BYE to SBC, and SBC returns 200OK message; SBC sends to media server and removes (TEARDOWN) message, and the request video/audio is taken out stitches; Media server returns 200OK message; Mobile switching centre sends to terminal A and discharges (release)/disconnecting signal (clearing signal CLF) message, and disconnection and release are connected with terminal A's; Pathway closure (Channel closeing) is informed to SBC sendaisle control event notice (CHNCONTROL EVENT NOTIFICATION) by mobile switching centre, can also send to call out dependent event notice (CALLRELATED EVENT NOTIFICATION) request call release (Call release).

In addition as shown in Figure 5, be another kind of networking structure, be that with the foregoing description difference this system is for monitoring the implementation of present networks other network terminals in addition.Comprise among Fig. 5: media stream server 602 with and under media client 601, Lawful interception gateway 603,

mobile switching centre

604 and 605, to the east of

media gateway

606 and 607, border conversation controller 608, ring-back tone music 609 (Music Ring BackTone, MTBT), video system 610 (Video System), next generation network 611 (Next GenerationNetwork, NGN), IP Multimedia System 612 can be in the lump with reference to figure 3.

In this system, the MSC Server of mobile soft switch and mobile media gateway (Mobile MediaGateway, MGW) can support embedded video interconnection and translation function, can finish the H.324M mutual conversion of multiplex stream and RTP separated flow, realize the video interconnection of (as 3G and SIP video terminal) between 3G video terminal and other video terminal or system.The Home Network video monitor directly MGW output H.324M arrive MC, the networking of monitoring networking project local exchange is constant;

At next generation network (Next Generation Network, during NGN) with the intercommunication of WCDMA Internet video, NGN transmits video data to MGW by gateway exchange, the built-in VIG of MGW finishes RTP and conversion H.324M, even NGN this targeted customer that do not deploy to ensure effective monitoring and control of illegal activities, the Target that this user is set in the WCDMA network also can listen in the WCDMA network equally.

Embodiment three, when the monitoring cost requirement is very high, may requires to provide and monitor the high audiomonitor of purchasing price of still being unwilling again, and present embodiment is a kind of easy monitoring scheme.The scheme of video monitor can for: to core net the eavesdropping target is set by a client, core net outputs to some terminals to the video of monitoring, can be at the other video of monitoring of terminal.

As shown in Figure 6, the networking structure schematic diagram, to mobile switching centre 702 (mobile switching centre 702 can be soft switch Msoft3000) eavesdropping target is set as mark's computer program (Mark Client) by terminal 701 here in the monitoring side, if the eavesdropping target has video calling, Msoft3000 and SBC (704) set up link then UMG (703) video data stream is sent to SBC (704), SBC (704) is converted into the universal media form after receiving this data flow, be sent on the media stream server 705, the staff just can carry out program request by 706 pairs of medium of media client of media stream server 705 afterwards, operations such as analysis.

This simple and easy video monitor scheme does not need to build expensive listening center equipment, and it is just passable only to need to build a media server.This scheme can be used for the test of field test office equally, because the Pilot office network can not be connected on the MC at national security center, the simple and easy video monitor scheme that this scheme provides, be used in Pilot office validation test video monitor function, (Service Provider SVP) realizes that cost is lower to communications equipment manufacturer and service provider.

The idiographic flow that said system realize to be monitored as shown in Figure 7 because similar with Fig. 4, can simultaneously also can be referring to Fig. 4.

801) Mark Client is provided with to MSC by the X1 interface and monitors number and receive that X1SetTargetResponse carries successfully (Successful) cell, and Target does caller or when called, trigger and monitor.Detailed process can connect (Connect) message for: MCS sends to Mark Client, Mark Client returns the connection request response, MCS sends logical device address (LDA) (LogicalEquipment Address to Mark Client, LEA) strategy (Star t), the response of Mark Client return address; MCS sends to Mark Client target (Target) message is set, the address information of the equipment that can monitor for the quilt that is provided with, the response of Mark Client return address;

IAM message is the request of connecting that MSC initiates to the monitoring side, and carries monitoring users information in the subaddressing.As shown in table 3:

Table 3

Calling terminal address Calling party subaddress	Carry the Target number
		Called end address Called party subaddress	Carry and call out identity parameters such as (CallID)

Caller subaddressing and called party subaddress all carry in visit transportation (Access Transport), such as Q.763 definition.

Above-mentioned 801) after the intercept target setting finished, MSC began normal call flow; (Apply Charging IAM) gives SBC to send initial address message then; The full message in SBC return address (AddressComplete Message, ACM) also (Answer Message, ANM) message are replied in transmission; After this MSC just can send out video to BSC, and this video can be multiplexing code stream H.223.

Flow process between SBC and RTSP server and RTSP server and the Client is as the 2.2.1.4 chapters and sections.

802) be similar to 502 among Fig. 4) be the negotiation of SBC and media server to the video media transmission parameter; Concrete negotiations process can for: SBC sends announcement (ANNOUNCE) message to media server and carries media description (media description); Media server returns request success message (200OK) can also return the transport-type that option (Options) inquiry is supported, for example whether support the communications industry standard agreement video format (Third Generation Partnership Project file format, 3GP); SBC returns 200OK message to media server, and media server is to the transmission parameter of the setup message sets Voice ﹠ Video of SBC transmission Voice ﹠ Video, and SBC returns 200OK message; Media server sends to SBC and writes down (Record) message automatically, the result that indication SBC record is consulted, and SBC returns 200OK message; SBC can transmit video to media server according to above-mentioned negotiation parameter then.

803) be similar to 505 among Fig. 4) be the parameter negotiation of Client before media server request medium; The process of consulting can be provided with message the video transmission parameter is set for: Client sends to media server; Client can send to media server and broadcast request message, and after media server returned 200OK message, media server can be to the real-time displaying video stream of Client; Client can also send to media server and suspend request, and media server returns 200OK message and suspends the transmission of video.

Subsequent step is that terminal A finishes the flow process that video is connected with terminal B, be general process ends, specific implementation can discharge request message for: MSC sends to SBC, and SBC sends to media server and discharges (release)/disconnecting signal (clearing signal CLF) message; Media server returns 200OK message; SBC sends disconnecting signal (clearing signal CLF) message to MSC.

Embodiment four, and as shown in Figure 8, as the Another application scene of embodiment one, the difference of present embodiment and embodiment three is: present embodiment does not have parameter negotiation H.245, but has set up the RTP media channel for the monitoring to sip user, specifically comprises:

As shown in Figure 8, step 901,902,903 with the step 801,802, the 803rd of embodiment three, identical, do not repeat them here; Difference is, after the present embodiment step 901, linking of setting up between MC and BSC is the RTP media channel, set up the RTP media channel flow process can for: MC sends to BSC and invites (Invite) message, and BSC sends to MC and attempts (100 Trying) message; BSC sends response (180 ringing) message to MC; BSC sends 200OK message to MC; MC sends to BSC and confirms (ACK); BSC is to MC delivery option (Options) message; MC sends 200OK to BSC; Link establishment has MC to send the RTP Media Stream to BSC then.

Embodiment five, and as shown in Figure 9, the embodiment of the invention also provides a kind of mobile switching centre, comprising:

Call request receiving element 1001 is used to receive the setup requests relevant with intercepted user;

Type of call determining unit 1002 is used for determining that whether current calling is video call H.324;

Link establishment unit 1003 is used for setting up transmission link if video call H.324 then carries out Signalling exchange with boarder controller SBC;

Video data receiving element 1004 is used to receive H.324 video data;

Video data sends unit 1005, after being used to receive H.324 video data, to H.324 by the transmission link of setting up, video data is sent to SBC, finishing H.324 by SBC, data send to listening center with the data after the conversion by the transmission link between the RTSP server of SBC and listening center MC to the format conversion of RTSP data.

In the such scheme, by video media being changed and sent to audiomonitor at the border conversation controller, realized video monitoring, MC need not upgrade, than the easier realization of upgrading MC.

As shown in figure 10, above-mentioned mobile switching centre can also comprise:

Negotiation element 1101 is used for carrying out signaling by SIP signaling and SBC and consults, and finishes the SIP signaling after the conversion of RTSP signaling at SBC, carries out the negotiation of parameter by the RTSP server among RTSP signaling and the MC.

Above-mentioned execution mode can be provided with the transmission parameter of video through consultation neatly, and to the control of video quality etc.

Further, above-mentioned video data sends unit 1005, also is used for if not video call H.324, and then the media data with current calling sends to MC.

As shown in figure 11, above-mentioned mobile switching centre can also comprise:

Negotiation data transmitting element 1201 is used for the negotiation parameter between the calling and called is sent to SBC by the link between MSC and the SBC, is beneficial to SBC and utilizes these negotiation parameter to participate in 324 video datas of receiving are resolved.

In the above-mentioned implementation, mobile switching centre is by transmitting negotiation parameter between calling and called, can allow SBC convenient when resolving H.324 video data.

Embodiment six, and as shown in figure 12, the embodiment of the invention also provides a kind of system of Lawful Interception, comprising:

Mobile switching centre 1301 is used to receive the setup requests relevant with intercepted user; Determine that whether current calling is video call H.324; If video call H.324 then carries out Signalling exchange with SBC (1302), set up transmission link; After receiving H.324 video data, by the transmission link set up H.324 video data be sent to SBC (1302);

Boarder controller 1302 is used for carrying out Signalling exchange with the RTSP server of listening center, sets up transmission link; After receiving above-mentioned H.324 video data, finish the format conversion of data H.324 to the RTSP data, with the data after the conversion by and the RTSP server of MC between transmission link send to MC.

Said system by video media being changed and sent to audiomonitor at the border conversation controller, has realized video monitoring, and MC need not upgrade, than the easier realization of upgrading MC.

Further,

Above-mentioned mobile switching centre 1301 also is used for carrying out signaling by session initiation protocol SIP signaling and SBC (1302) and consults;

Above-mentioned boarder controller 1302 also is used to finish the SIP signaling after the conversion of RTSP signaling, carries out the negotiation of parameter by the RTSP server among RTSP signaling and the MC.

Further,

Above-mentioned mobile switching centre 1301 also is used for if not video call H.324, and then the media data with current calling sends to MC.

Further,

Above-mentioned mobile switching centre 1301, also be used for the negotiation parameter between the calling and called is sent to SBC (1302) by the link between MSC and the SBC (1302), be beneficial to SBC (1302) and utilize these negotiation parameter to participate in 324 video datas of receiving are resolved.

One of ordinary skill in the art will appreciate that all or part of step that realizes in the foregoing description method is to instruct relevant hardware to finish by program, described program can be stored in a kind of computer-readable recording medium, the above-mentioned storage medium of mentioning can be a read-only memory, disk or CD etc.

More than the methods, devices and systems of a kind of Lawful Interception that the embodiment of the invention provided are described in detail, used specific case herein principle of the present invention and execution mode are set forth, the explanation of above embodiment just is used for helping to understand method of the present invention and core concept thereof; Simultaneously, for one of ordinary skill in the art, according to thought of the present invention, the part that all can change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.

Claims

1. the method for a Lawful Interception is characterized in that, comprising:

Receive the setup requests relevant with intercepted user;

Determine that whether current calling is video call H.324;

2. according to the described method of claim 1, it is characterized in that described and SBC carries out Signalling exchange and comprises:

Carry out signaling by session initiation protocol SIP signaling and SBC and consult, SBC finishes the SIP signaling after the conversion of RTSP signaling, carries out the negotiation of parameter by the RTSP server among RTSP signaling and the MC.

3. according to the described method of claim 1, it is characterized in that whether described definite current calling is for H.324 also comprising after the video call:

If not video call H.324, then the media data with current calling sends to MC.

4. according to the described method of claim 1, it is characterized in that, also comprise:

Negotiation parameter between the calling and called is sent to SBC by the link between MSC and the SBC, is beneficial to SBC and utilizes these negotiation parameter to participate in the H.324 video data of receiving is resolved.

5. a mobile switching centre is characterized in that, comprising:

The video data receiving element is used to receive H.324 video data;

Video data sends the unit, after being used to receive H.324 video data, to H.324 by the transmission link of setting up, video data is sent to SBC, finished by SBC that H.324 data are to the format conversion of RTSP data, the data after SBC will change send to listening center by the transmission link between the RTSP server of SBC and listening center MC.

6. according to the described mobile switching centre of claim 5, it is characterized in that, also comprise:

Negotiation element is used for carrying out signaling by SIP signaling and SBC and consults, and finishes the SIP signaling after the conversion of RTSP signaling at SBC, and SBC carries out the negotiation of parameter by the RTSP server among RTSP signaling and the MC.

7. according to the described mobile switching centre of claim 5, it is characterized in that,

Described video data sends the unit, also is used for if not video call H.324, and then the media data with current calling sends to MC.

8. according to the described mobile switching centre of claim 5, it is characterized in that, also comprise:

The negotiation data transmitting element is used for the negotiation parameter between the calling and called is sent to SBC by the link between MSC and the SBC, is beneficial to SBC and utilizes these negotiation parameter to participate in the H.324 video data of receiving is resolved.

9. the system of a Lawful Interception is characterized in that, comprising:

10. according to the described system of claim 9, it is characterized in that,

Described mobile switching centre also is used for carrying out signaling by session initiation protocol SIP signaling and SBC and consults;

Described boarder controller also is used to finish the SIP signaling after the conversion of RTSP signaling, carries out the negotiation of parameter by the RTSP server among RTSP signaling and the MC.

11. according to the described system of claim 9, it is characterized in that,

Described mobile switching centre also is used for if not video call H.324, and then the media data with current calling sends to MC.

12. according to the described system of claim 9, it is characterized in that, also comprise:

Described mobile switching centre also is used for the negotiation parameter between the calling and called is sent to SBC by the link between MSC and the SBC, is beneficial to SBC and utilizes these negotiation parameter to participate in the H.324 video data of receiving is resolved.