KR20060105935A - Method for distribution of security key in location information system based on supl - Google Patents

Abstract

The present invention provides a method for distributing a secret key between H-SLP and SET and a secret key between V-SLP and SET when SUPL service is started from a network in a location information system based on Secure User Plane Location (SUPL). Enables the use of a message authentication code (MAC) that can provide authentication, integrity verification, and prevention of reuse of SUPL_INIT messages delivered from the SLP to the SET through a key shared between the SLP and the SET. Accordingly, the SUPL_INIT message can be encrypted and delivered by establishing a PSK-TLS session or sharing a key that can use another symmetric key algorithm by the secret key distribution method according to the present invention.

SUPL, SLP, SET, Secret Key

Description

Method of distributing secret key in SPL-based location information system {METHOD FOR DISTRIBUTION OF SECURITY KEY IN LOCATION INFORMATION SYSTEM BASED ON SUPL}

1 is a diagram showing a procedure for performing SUPL in the case of non-Roaming with the SUPL service being started from the network.

2 is a diagram illustrating a procedure for performing SUPL in the case of Roaming with the SUPL service being started from the network.

3 is a view showing a bootstrapping using procedure of the 3GPP GBA Architecture applied to the present invention.

4 is a diagram illustrating a secret key distribution procedure between an H-SLP and a SET using the GBA Bootstrapping procedure when the SUPL service is started from the network and the SET is non-roaming.

5 is a diagram illustrating a secret key distribution procedure between an H-SLP and a SET using the GBA Bootstrapping procedure when the SUPL service is started from the network and the SET is roaming.

FIG. 6 illustrates a procedure for sharing a secret key for use in a PSK-TLS session between a V-SPC and a SET using a 3GPP GBA Bootstrapping using procedure. FIG.

The present invention relates to a secure user plane location (SUPL) based location information system, and more particularly, to a secret key distribution method between an SLP and a SET.

In a mobile communication system, a mobile communication network includes a related function unit for calculating a location of a terminal, and provides a location service that delivers the location of the terminal to a certain entity periodically or on request.

The network structure related to the location service is different depending on an internal network structure such as 3GPP or 3GPP2, and the current terminal position calculation method includes a cell-ID scheme for transmitting an ID of a cell to which a terminal belongs, and a radio wave from a terminal to each base station. After measuring the time to reach, there is a method of calculating the position of the terminal using a triangulation and a method using a GPS.

However, in order to provide the location service to the user, considerable signaling and location information must be transmitted between the mobile terminal and the location server. Recently, standardized location technologies for providing location services, that is, location services based on the location of a mobile terminal, are rapidly spreading. Such technologies may be provided through a user plane and a control plane, and as an example of the technology, a secure user plane location (SUPL) providing a location service through the user plane is known. .

The SUPL is an efficient method of transmitting location information necessary for calculating a location of a mobile station. The SUPL is a user plane for delivering location assistance information such as GPS assistance and carrying a positioning technology related protocol between a mobile terminal and a network. Use a data bearer.

In general, the SPUL network related to the location service in the location information system includes a SUPL agent, a SLP (SUPL Location Platform), and a SET (SUPL Enabled Terminal).

The SUPL agent represents a logical service access point using actual measured location information, and the SLP represents a SUPL service access point of a network portion that accesses network resources to obtain location information.

In addition, the SET is a device capable of communicating with a SUPL network using a SUPL interface, for example, a user terminal (UM) of UMTS, a mobile station (MS) of GSM, an IS-95 MS or a laptop having a built-in SET function. Laptop computer) or PDA (Personal Digital Assistants). Also, the SET may be various mobile terminals connected through a wideband LAN (WLAN). The SET interworks with the network via a user plane bearer to support definition procedures in SUPL.

In addition, in the location information service, the network originally registered by the user is called a home network, and when the user moves and is located in an area other than the home network area, the network of the corresponding area is called a visited network. do. Thus, SLP in the home network is referred to as H-SLP (Home-SLP) and SLP in the visited network is referred to as V-SLP (Visited-SLP). In this case, when starting the SUPL procedure in the network, the first SLP to which an external client connects is called a requesting SLP (R-SLP), which may or may not be the same as the H-SLP as a logical entity. In addition, the SET that targets the current position tracking is defined as a target SET.

In addition, the SLP, which is a network element, is an SLC (SUPL Positioning Center) that is an entity for calculating an actual position and an SLC that plays a role of SLP other than calculating position information, for example, roaming and resource management. SUPL Location Center). Accordingly, the SET may calculate location information through communication with the SPC via SLC (Proxy mode), or may open a connection with the SPC to calculate location information (Non-proxy mode).

1 illustrates a procedure for performing SUPL in case of SUPL service is started from a network and is non-roaming.

Referring to FIG. 1, first, a SUPL agent transmits a Mobile Location Protocol (MLP) Standard Location Immediate Request (MLP) message to an SLP, and the SLP roams a target SET based on routing information. It determines whether or not the target SET supports SUPL based on the SET lookup information.

If the SET is not roaming and supports SUPL, the SLP sends a SUPL INIT message to the SET to initiate the SET and SUPL procedures. The SUPL INIT message should include at least the session-id, the address of the SLP, and the positioning method to be used. In addition, the SUPL INIT message may include a notification when a user needs a notification related to location information when checking the privacy of a SET using an ms-id included in the MLP SLIR message.

The SET having received the SUPL INIT message requests a data connection to a packet data network (a network such as 3GPP or 3GPP2) when no data connection is currently open in any network (Data connection).

When the data connection is complete, the SET establishes a Transport Layer Security (TLS) session (Encryption Channel) with the SLP, where the PSK-TLS is used if there is a Pre-Shared Key (PSK) that is already shared. Set up a session using. Therefore, the destination SET initiates the actual positioning procedure by sending a SUPL POS INIT message to the SLP, and the SUPL POS INIT message includes at least session-id, lid and SET capabilities. The procedure from the SUPL_INIT message transmission to the SUPL POS INIT message transmission is performed for a predetermined time (timer ST2).

After a predetermined time (timer UT2) has elapsed after transmitting the SUPL POS INIT message, the SET and SLP perform a SUPL POS procedure for exchanging successive messages for actual positioning, and the SLP or SET is a continuous operation for positioning. Calculate the location of the destination SET through a generic message.

Therefore, when the position of the target SET is calculated, the V-SLP (V-SPC) notifies the end of the SUPL procedure by sending a SUPL END message to the SET to terminate the TLS session established between the V-SLP and the SET, and the MLP SLIA message. Transmit location information result of SET to SUPL agent through.

2 illustrates a procedure for performing SUPL in the case of Roaming where the SUPL service is started from the network. In FIG. 2, the RLP message between the H-SLP and the V-SLP is securely delivered using HTTPS. Since the sessionID is constantly increased, it is assumed that the message can be reused through the sessionID when the message is reused.

First, when the destination SET roams, the H-SLP forwards the session-id, msid and QoS in the SUPL START message to the V-SLP via the RLP SSRLIR (Standard SUPL Roaming Location Immediate Request), and the V-SLC sends the H-SLP In other words, the address and port number of the V-SLP (exactly V-SPC) are transmitted using the RLP SSRLIA message.

When the RLP SSRLIA message is input, the H-SLP randomly generates an Auth_Key (Pre Shared Key) to be used between the V-SLP and the SET and then transfers it to the V-SLP through the RLP SSRP message. The Auth_Key is used as an authentication result between the V-SLP and the SET and later used as the PSK when creating a Pre Shared Key-Transport Layer Security (PSK-TLS) session between the V-SLP and the SET.

Accordingly, the H-SLP transmits a SUPL INIT message to the SET to initiate the SET and SUPL procedures. The SUPL INIT message must include at least a session-id, an SLP address (V-SPC address), and a positioning method to be used. do.

The SUPL INIT message may optionally include a notification when a user needs a notification related to location information as a result of confirming the privacy of the target SET using the msid of SUPL START. In addition, KeyID and MAC are also optionally included as parameters of the SUPL INIT message. In this case, the KeyID is used to distinguish a key for calculating a message authentication code (MAC), and the MAC is used to verify the integrity of the SUPL INIT message.

The SET receiving the SUPL INIT message establishes an SLP and a PSK-TLS session, where the SLP and the SET establish a TLS session using a pre-shared key that is already shared. The SET transmits the hashed result to the H-SLP using a hash algorithm such as SHA to determine the integrity verification and reuse of the received SUPL_INIT message, and the H-SLP transmits the hash value included in the SUPL_INIT message. Verify integrity and reuse.

If the integrity of the SUPL_INIT message is successfully verified, the H-SLP includes the Auth_Key in the AUTH_RESP message via the established TLS session and forwards it to the SET so that the V-SLP and the SET share the Auth_Key successfully. Used as the PSK for the PSK-TLS session.

Therefore, by using the Auth_Key which is the PSK set between the V-SLP and the SET, the SET establishes the V-SLP and PSK-TLS sessions and then performs a positioning procedure to securely transmit the location information.

As described above, PSK-TLS is used to provide confidentiality between H-SLP and SET in the current procedure of performing SUPL service. When SUPL service is started from the network, H-SLP sends a SUPL INIT message. Inform SET to start SUPL service. However, since the SUPL INIT message is transmitted before the TLS session is established, the SUPL INIT message cannot be safely delivered through TLS. For this reason, the SUPL INIT message can be modified or reused from a malicious attacker.

An object of the present invention is to provide a secret key between H-SLP and SET and a secret key distribution method between V-SLP and SET when SUPL service is started from the network.

Another object of the present invention is to provide a method for protecting a SUPL INIT message by performing a PSK distribution procedure before delivering the SUPL INIT message.

In order to achieve the above object, in the SUPL (Secure User Plane Location) based location information system, the secret key distribution method according to the present invention, SLP (SUPL Location Platform) is set when the SUPL service is started from the network Requesting to start a local key distribution procedure; A SET performing the key distribution procedure to share an SLP and a secret key for establishing an encryption channel; After the SLP generates a parameter for integrity verification using the secret key, the SLP includes the parameter in the SUPL INIT message and transmits the parameter to the SET.

Preferably, the key distribution procedure represents a GBA Bootstrapping procedure.

Preferably, the parameter represents a message authentication code (MAC).

Preferably, the SLP calculates a message authentication code (MAC) or encrypts a SUPL INIT message using a symmetric key algorithm using a shared secret key.

In order to achieve the above object, in the SUPL (Secure User Plane Location) based location information system, the secret key distribution method according to the present invention, H (Home) -SLP (SUPL) when the SUPL service is started from the network Requesting to start a key distribution procedure with the SET; The SET performing a first key distribution procedure to share the SLP with a secret key for establishing an encryption channel; Calculating, by the SLP, a parameter for integrity verification using the shared secret key, and including the parameter in a SUPL INIT message to the SET; The SET performing a second key distribution procedure to share a secret key for use in an encryption session between the V-SLP and the SET; V-SLP establishes a SET and a PSK-TLS session by using the shared secret key.

Preferably, the H-SLP includes the address of a Bootstrapping Server Function (BSF) in SUPL START, and further includes transmitting the V-SLC (SUPL Location Center) of the V-SLP through an RLP SSRLIR message.

Preferably, the parameter represents a message authentication code (MAC).

Preferably, the first and second key distribution procedure represents a GBA Bootstrapping procedure, wherein the first key distribution procedure is started from the H-SLP and the second key distribution procedure is started only from the SET.

Preferably, the SLP is H-SLP or V-SPC (SUPL Positioning Center).

Preferably, the SLP calculates a message authentication code (MAC) or encrypts a SUPL INIT message using a symmetric key algorithm using a shared secret key.

Hereinafter, preferred embodiments of the present invention will be described.

The present invention provides a secret key between H-SLP and SET and a secret key distribution method between V-SLP and SET when the SUPL service is started from the network. In particular, the present invention performs a MAC or encryption function to protect the SUPL_INIT message transmitted from the SLP to the SET through a key shared between the SLP and the SET by performing a distribution procedure of the PSK (Pre-Shared Key) before delivering the SUPL INIT message. We propose a way to do this. To this end, the present invention may use a Generic Bootstrapping Architecture (GBA) Bootstrapping usage procedure of 3GPP as an example of a method of distributing a Pre-Shared Key (PSK). However, since the procedure of using the GBA Bootstrapping can be performed only by a request of the SET, the present invention starts the procedure by adding a new Bootstrapping Request message transmitted from the H-SLP to the SET when the SUPL service is started from the network. Inform SET.

Accordingly, the SET receiving the Bootstrapping Request message can eventually share the symmetric key with the H-SLP, so that the H-SLP can transmit the encrypted SUPL INIT message.

3 shows a Bootstrapping procedure of the 3GPP GBA Architecture. The GBA Bootstrapping procedure can be started only from a user equipment (UE). The UE and BSF (Bootstrapping Server Function) performed the process of agreeing to use the GBA Architecture through the interface (Ua, Zn), and performed the authentication and key matching process through the Authentication and Key Agreement (AKA) process. It is assumed that you have finished sharing both the Key) and the Integrity Key (IK). Thus, the UE and BSF are the result of the GBA initialization procedure. The shared key (symmetric key) Ks = CK || IK has been shared.

Ua is an interface between the UE and NAF, and a secure encryption channel is formed using the same key material by performing HTTP Digest AKA. In addition, Zn is an interface between NAF and BSF. When NAF and BSF are in the same network, a secure encryption channel is formed using IPSec or the like according to 3GPP NDS / IP [33.210]. On the other hand, when the NAF and the BSF are in different networks, a secure encryption channel is formed between the D-Proxy and the BSF using TLS.

As shown in FIG. 3, if the symmetric key Ks shared between the UE and the BSF is available, the UE uses KDF () to derive Ks_NAF from Ks. Then, the UE attaches a Tidentifier (Transaction identifier) and MAC to the Application Request message and delivers it to the NAF to inform the start of the Bootstrapping usage procedure.

The NAF requests the key material by passing the requested TIdentifier from the UE and the hostname of the NAF to the BSF, and the BSF checks the hostname of the NAF for the NAF authentication request, and if it is an authenticated NAF, Ks_NAF and Profile for the TIdentifier. Deliver to NAF. The Profile includes the lifetime of Ks_NAF.

The NAF receiving the Authentication Answer from the BSF notifies the UE that the shared key (symmetric key) between the UE and the NAF is set after storing the Ks_NAF and the Profile. Therefore, the UE and NAF can use Ks_NAF to encrypt or calculate MAC value using symmetric key algorithms such as AES and DES, and can derive encryption key and integrity verification key from Ks_NAF if necessary. In addition, through authentication and key matching information between the UE and the BSF, the BSF distributes a secret key (Ks_NAF) for the UE and the NAF.

4 illustrates a secret key distribution procedure between the H-SLP and the SET using the GBA Bootstrapping usage procedure when the SUPL service is started from the network and the SET is non-roaming.

As shown in FIG. 4, the SLP determines whether the destination SET is roaming using routing information, and determines whether the destination SET supports SUPL based on the SET lookup information. At this time, the BSF and the SET share a Pre Shared Key (Ks).

Subsequently, the SLP sends a Bootstrapping Request message to the destination SET to indicate the start of the key distribution procedure, more specifically the GBA Bootstrapping usage procedure of 3GPP.

When the Bootstrapping Request message is received, the SET derives Ks_NAF from Ks shared through the Bootstrapping Procedure, attaches a Tidentifier and a MAC to the Application Request message, and delivers it to SLP (= NAF) to use Bootstrapping procedure. Announce the beginning of SLP requests key material by passing Tidentifier requested from SET and hostname of NAF to BSF, and BSF checks SLP's hostname for SLP's authentication request.In case of authenticated NSLP, Ks_NAF and Profile for the corresponding TIdentifier Deliver to SLP. The profile includes information of the terminal. Receiving the Authentication Answer from the BSF, the SLP stores the Ks_NAF, Profile, and Key Life Time and then informs the SET that the shared key (symmetric key) (Ks_NAF) between the SET and the SLP is set. That is, the BSF authenticates the SLP, derives Ks_NAF from the encryption key (Ks) shared between the BSF and the target SET, and transfers it to the SLP stably so that the shared key (Ks_NAF) between the SLP and the SET is established. Is set.

When the shared key (= secret key) is distributed between the SLP and the SET by the key distribution procedure, the SLP generates a MAC, which is a parameter for integrity verification, using the shared key (Ks_NAF) and then includes the SET in a SUPL INIT message. Begin the SET and SUPL procedure. In addition to the MAC, the SUPL INIT message should include at least a session-id, an address of an SLP, a positioning method to be used, and may also include a notification when a user needs a notification related to location information. Therefore, SET calculates the MAC using the shared key (Ks_NAF) and compares it with the MAC included in the received SUPL INIT message. If the two MACs are identical, the SET determines that the SUPL INIT message has not changed (integrity check).

Afterwards, the SET establishes a TLS session with the SLP after performing a data connection.If the SLP and SET already have a shared key (Pre-Shared Key) or if the user agrees to use the GBA, the PSK-TLS is used. To establish a session.

Accordingly, the destination SET initiates a positioning related procedure by sending a SUPL POS INIT message to the SLP. The SUPL POS INIT message includes at least session-id, lid, SET capabilities, and a hash result of the SUPL_INIT message. Therefore, it is possible to check whether the SUPL_INIT message transmitted by the H-SLP is correctly transmitted to the SET through the hash value of the SUPL_INIT.

When performing the positioning related procedure, the SET and SLP exchange successive messages for actual positioning, and calculate the position of the destination SET through successive messages for positioning. Once the position of the destination SET is calculated, the SLP sends a SUPL_END message to the SET to inform the end of the SUPL procedure, and the SET closes the TLS session with the SLP.

5 is a diagram illustrating a secret key distribution procedure between the H-SLP and the SET using the GBA Bootstrapping usage procedure when the SUPL service is started from the network and the SET is roaming.

Referring to FIG. 5, the H-SLP (Home SLP) determines whether the destination SET is roaming using routing information, and determines whether the destination SET supports SUPL using the lookup information.

H-SLP sends session-id and msid in SUPL START message to V-SLC via RLP SSRLIR, and V-SLC sends V-SPC address and port number to H-SLPC using RLP SSRLIA message. do. In addition, the H-SLP randomly generates an Auth_Key (Pre Shared Key) to be used between the V-SLP and the SET and delivers the V-SLP through an RLP SSRP message. The Auth_Key is used as the authentication result between the V-SLP and the SET and later used as the PSK when creating a PSK-TLS session between the V-SLP and the SET.

When all of the above operations are performed, the H-SLP sends a Bootstrapping Request message to the destination SET for the authentication of the UE and the SLP to inform the start of the GBA Bootstrapping usage procedure of 3GPP, which is a key distribution procedure. In the key distribution procedure, the BSF authenticates the H-SLP, derives Ks_NAF from the encryption key (Ks) shared between the BSF and the target SET, and then stably forwards the H-SLP to the H-SLP to share it between the H-SLP and the SET. The key (symmetric key) Ks_NAF is set.

When the shared key (= secret key) is distributed between the H-SLP and the SET by the key distribution procedure, the H-SLP sends a SUPL INIT message to the SET to start the SET and SUPL procedure. The SUPL INIT message should include at least a session-id, an address of an SLP, a positioning method to be used, and may include a notification when a user needs a notification related to location information. Also, by adding a MAC (Message Authentication Code) to the SUPL_INIT message, it is possible to verify that the SUP_INIT message is not changed during transmission.

The SET receiving the SUPL INIT message establishes an H-SLP and a PSK-TLS session, where the H-SLP and the SET establish a PSK-TLS session using a pre-shared key. do. The SET transmits the hashed result to the H-SLP using a hash algorithm such as SHA to determine the integrity verification and reuse of the received SUPL_INIT message, and the H-SLP transmits the hash value included in the SUPL_INIT message. Verify integrity and reuse.

If the integrity of SUPL_INIT message is successfully verified, H-SLP includes Auth_Key in AUTH_RESP message through SET TLS session and passes to SET, so V-SLP and SET can successfully share Auth_Key. Used as the PSK for the PSK-TLS session. As such, when the V-SLP and the SET successfully share the Auth_Key, the PSK-TLS session between the H-SLP and the SET is peered.

After receiving the SUPL INIT message, the SET requests a data connection to a packet data network (3GPP or 3GPP2, etc.) when no data connection is currently open to any network (Data connection).

When a data connection is made, the SET establishes a V-SLP (V-SPC) and PSK-TLS session for a predetermined time using the Auth_Key, which is the PSK set between the V-SLP and the SET, and then sends a SUPL POS INIT message. Transmit to V-SPC to initiate the actual positioning procedure. The SUPL POS INIT message includes at least session-id, lid and SET capabilities. After a predetermined time (timer UT2) has elapsed after transmitting the SUPL POS INIT message, SET and V-SLP (V-SPC) perform a SUPL POS procedure for exchanging successive messages for actual positioning. The SLP or SET calculates the position of the destination SET through successive messages for positioning.

Therefore, when the position of the target SET is calculated, the V-SPC sends a SUPL END message to the SET to inform the termination of the SUPL procedure and terminates the PSK-TLS session established between the V-SLP and the SET. In addition, the V-SLC transmits the location information result of the SET to the V-SLC through internal communication, and the V-SLC includes the location information result of the SET in the RLP SSRP message and then sends the result to the H-SLP. send.

6 illustrates a method of sharing a secret key to be used in a PSK-TLS session between a V-SPC and a SET using a 3GPP GBA Bootstrapping usage procedure.

Currently, OMA SUPL protects location information by using PSK-TLS between V-SPC and SET, but the part about secret key sharing between V-SPC and SET can be changed. In order to exchange a secret key between the V-SPC and the SET, the present invention deletes the RLP-SSRP message transmission procedure and the PSK-TLS session establishment and termination procedure between the H-SLP and the target SET in the message flow of FIG. Use the bootstrapping usage procedure.

That is, in FIG. 5, the H-SLP distributes the secret key (Auth_key) between the V-SLP (actual V-SPC) and the SET to the V-SLP and the SET. Use the GBA BUP to share. As such, to perform the GBA BUP procedure between the V-SLP and the SET, the H-SLP must transmit the address of the BSF to the V-SLC.

Therefore, in FIG. 6, the H-SLP and the SET share the secret key by using the GBA Bootstrapping Usage Procedure (GBA BUP), which is basically the same as FIG. 5, except that the H-SLP uses the SULP START message through the RLP SSRLIR message. In this case, the BSF address is transmitted to the V-SLC and the RLP-SSRP message transmission procedure is not performed. That is, H-SLP transmits the address of BSF to V-SLC along with session-id and msid in SUPL START message through RLP SSRLIR message, and SET subsequently executes GBA BUF procedure for exchanging secret key between V-SPC. When doing so, the network address of the BSF is known. Therefore, the detailed description of the procedure of receiving the MLP SLIR message from the SUPL agent and sharing the secret key by performing the GBA BUP procedure with the H-SLP and the SET is omitted.

When the shared key (symmetric key) Ks_NAF ₁ is shared between the H-SLP and the SET by the key distribution procedure, the SLP generates a MAC using the shared key Ks_NAF and then includes the SET in a SUPL INIT message. Begin the SET and SUPL procedure by sending a call to. In addition to the MAC, the SUPL INIT message should include at least a session-id, an address of an SLP, a positioning to be used, and may include a notification when a user needs notification regarding location information. In addition, a KeyID and a MAC may be optionally included in the SUPL_INIT message. The KeyID is used to distinguish a key for calculating the MAC, and the MAC is used to verify the integrity of the SUPL_INIT message. Therefore, SET calculates the MAC using the shared key (Ks_NAF) and compares it with the MAC included in the received SUPL INIT message. If the two MACs are identical, the SET determines that the SUPL INIT message has not changed (integrity check).

Upon receiving the SUPL INIT message, the SET requests a data connection to a packet data network (such as 3GPP or 3GPP2) when no data connection is open to any network. Once the data connection is complete, the destination SET initiates the GBA BUP procedure with the V-SLP (V-SPC) to share the secret key. At this time, the BSF authenticates the V-SLC, derives Ks_NAF ₂ from the encryption key (Ks) shared between the BSF and the SET, and transfers it to the V-SPC, thereby sharing the shared key (symmetric key) between the V-SPC and the SET ( Ks_NAF ₂ ) is set.

When the shared key (symmetric key) (Ks_NAF ₂ ) is set between the V-SPC and the SET, the SET establishes a V-SPC and a TLS session, where the V-SPC and the SET are already shared secret keys (Pre-Shared). If there is a key) or if you agree to use GBA, use PSK-TLS to establish a session. When the PSK-TLS is set, the SET sends a SUPL POS INIT message to the V-SPC to start the actual positioning procedure. The SUPL POS INIT message includes at least session-id, lid and SET capabilities. After a predetermined time (timer UT2) has elapsed after transmitting the SUPL POS INIT message, SET and V-SLP (V-SPC) perform a SUPL POS procedure for exchanging successive messages for actual positioning. The SLP or SET calculates the position of the destination SET through successive messages for positioning.

When the position of the target SET is calculated as described above, the V-SPC sends a SUPL END message to the SET to inform the end of the SUPL procedure and terminates the PSK-TLS session established between the V-SLP and the SET. In addition, the V-SLC transmits the location information result of the SET to the V-SLC through internal communication, and the V-SLC includes the location information result of the SET in the RLP SSRP message and then sends the result to the H-SLP. send.

Therefore, the H-SLP delivers the location information of the target SET to the R-SLP using the RLP SRLIA message, and the R-SLP delivers the location information of the destination SET to the SUPL agent using the MLP SLIA message.

In the present invention, terms such as a symmetric key, a secret key, and a shared key are used, but the terms all have the same meaning.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, the present invention provides a secret key between H-SLP and SET and a secret key distribution method between V-SLP and SET when SUPL service is started from the network in SUPL based location tracking method. It is possible to use MAC that can provide authentication, integrity verification and reuse prevention of SUPL_INIT message delivered from SLP to SET through the key shared by. Accordingly, the SUPL_INIT message can be encrypted and delivered by sharing a shared key that can form a PSK-TLS session or use another symmetric key algorithm by the secret key distribution method according to the present invention.

Claims (16)

In the location information system based on SUPL (Secure User Plane Location), Requesting the start of a key distribution procedure by the SLP (SUPL Location Platform) when the SUPL service is started from the network; A SET performing a key distribution procedure to share the SLP and a secret key for establishing an encryption channel; And including a parameter for integrity verification in a SUPL INIT message by using the secret key shared by the SLP, and transmitting the same to a SET.   The method of claim 1, wherein the secret key A secret key distribution method characterized by representing a shared key and a symmetric key.   The method of claim 1 wherein the parameter is Secret key distribution method characterized in that the Message Authentication Code (MAC). The method of claim 1, wherein the key distribution procedure is A method for distributing secret keys characterized by the procedure for using GBA Bootstrapping. The method of claim 4, wherein the GBA bootstrapping procedure is used. Deriving Ks_NAF from the symmetric key Ks in the SET and transmitting an Application Request message to the SLP to inform the start of the GBA Bootstrapping procedure; SLP sends an Authentication Request message according to the Application Request message, requesting a key material to a bootstrapping server function (BSF); The BSF forwarding the Ks_NAF and the profile to the SLP at the request of the SLP; And storing, by the SLP, the delivered Ks_NAF and the profile, informing the SET that the shared key is set between the SET and the SLP. The method of claim 5, wherein the SLP is A secret key distribution method, comprising using a shared secret key to calculate a message authentication code (MAC) using a symmetric key algorithm or encrypting a SUPL INIT message. The method of claim 1, wherein when the SET roams the SLP is Secret key distribution method characterized in that the H (Home) -SLP. In the location information system based on SUPL (Secure User Plane Location), Requesting the start of a key distribution procedure to a SET when a SUPL service is started from a network; The SET performing a first key distribution procedure to share the SLP with a secret key for establishing an encryption channel; Using the shared secret key, an SLP including a parameter for integrity verification in a SUPL INIT message and delivering it to a SET; The SET performing a second key distribution procedure to share a secret key for use in an encryption session between the V-SLP and the SET; And a V-SLP establishing a SET and a PSK-TLS session by using the shared secret key. The method of claim 8, wherein the H-SLP includes an address of a bootstrapping server function (BSF) in SUPL START, and then transmitting the V-SLC to a SUL Location Center (V-SLC) through an RLP SSRLIR message. Secret key distribution method comprising a. The method of claim 8, wherein the secret key A secret key distribution method characterized by representing a shared key and a symmetric key. The method of claim 8, wherein the parameter is Secret key distribution method characterized in that the Message Authentication Code (MAC). The method of claim 8, wherein the first and second key distribution procedures Secret key distribution method characterized in that the GBA Bootstrapping procedure. 13. The method of claim 12, wherein the first key distribution procedure is Secret key distribution method, wherein the second key distribution procedure starts only from the SET. The method of claim 12, wherein the GBA bootstrapping procedure is used. Deriving Ks_NAF from the symmetric key Ks in the SET to inform the SLP of the start of the GBA Bootstrapping procedure using an Application Request message; SLP sends an Authentication Request message according to the Application Request message, requesting a key material to the BSF; The BSF forwarding the Ks_NAF and the profile to the SLP at the request of the SLP; And storing, by the SLP, the delivered Ks_NAF and the profile, informing the SET that the shared key is set between the SET and the SLP. The method of claim 14, wherein the SLP is Secret key distribution method characterized in that the H-SLP or V-SPC (SUPL Positioning Center). The method of claim 14, wherein the SLP is A secret key distribution method, comprising using a shared secret key to calculate a message authentication code (MAC) using a symmetric key algorithm or encrypting a SUPL INIT message.

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