WO2012040949A1

WO2012040949A1 - Method for fast handing over extensible authentication protocol (eap) authentication in mobile worldwide interoperability for microwave access (wimax) network

Info

Publication number: WO2012040949A1
Application number: PCT/CN2010/078490
Authority: WO
Inventors: 张玉清; 付安民; 刘奇旭
Original assignee: 中国科学院研究生院
Priority date: 2010-09-28
Filing date: 2010-11-08
Publication date: 2012-04-05
Also published as: CN101958898A; CN101958898B

Abstract

The present invention discloses a method for fast handing over extensible authentication protocol (EAP) authentication in a mobile worldwide interoperability for microwave access (WiMAX) network and relates to the field of handing over authentication in a mobile WiMAX network. The method includes the following steps: after a mobile station (MS)accesses to the mobile WiMAX network for the first time and completes the EAP authentication by an Authentication Authorization Accounting (AAA) server successfully, an access base station (BS) generates a credit bill for the mobile station (MS) using a multicast BS group key; when the MS needs to hand over to a new BS because of its movement, it can pass the identity authentication of target BS only by providing the credit bill of itself. With the method, an EAP re-authentication can be avoided and thereby safe and fast handover can be implemented.

Description

Fast switching method for EAP authentication in mobile WiMAX network

Technical field

The present invention mainly relates to the field of mobile WiMAX network handover authentication technology, and particularly relates to a method for supporting fast EAP (Extensible Authentication Protocol) handover authentication in a high speed mobile environment. Background technique

WiMAX (World Interoperability for Microwave Access) is an emerging broadband wireless access technology based on the IEEE 802.16 standard. It provides high-speed Internet-oriented connectivity with data transmission distances up to 50km. WiMAX also has the advantages of QoS guarantee, high transmission rate, and rich and diverse services. WiMAX has a high technology starting point and adopts advanced technologies such as 0FDM/0FDMA, AAS, and MIMO, which represent the future development of communication technologies. With the development of technical standards, WiMAX will gradually realize the mobilization of broadband services.

The development of the IEEE 802.16 family of standards began in 2001, but its first version was officially released in 2002. The IEEE 802.16d standard, officially approved by the IEEE in June 2004, is a revised version of the 802.16 family of standards and is a relatively mature and practical version of the standard. The IEEE Working Group released the 802.16e standard for broadband wireless access solutions that provide both high-speed data services and user mobility. The standard specifies a system that supports both fixed and mobile broadband wireless access. It operates in a licensed band of <6013⁄4 for mobility and supports user terminals to move at vehicle speeds. In order to meet the requirements of the global 4G wireless communication standard IMT-advanced, from 2007, the IEEE 802.16 working group began to develop a new 802.16 standard (that is, 802.16m), and released the first IEEE 802.16m in July 2009. Draft standard. Especially in October 2009, IEEE 802.16m was submitted to the ITU Telecommunication Union ITU and officially accepted as one of the 4G candidates.

Identity authentication and key agreement are an important security mechanism in WiMAX. It is an important guarantee for secure communication and protection of users and operators. In the pre-IEEE 802.16m version, both EAP and RSA authentication methods are supported. However, in the IEEE 802.16m standard, only EAP-based authentication is supported, and RSA-based authentication is no longer supported.

EAP is an authentication protocol defined in RFC 3748, which specifically includes various EAP authentication methods such as EAP-SIM, EAP-TLS, and EAP-AKA. The protocol consists of three roles: client, authenticator, and authentication server. In mobile WiMAX, MS (mobile station, mobile terminal;) is an EAP client, BS (base station) is an authenticator, and an AAA server (authentication authorization, accounting, accounting, and accounting server) in the home domain is EAP authentication server. The EAP client and the authentication server exchange information by performing the EAP method, and are in their The interrogator is used to pass information. If the EAP server allows the EAP client to access the network, the client and server will generate the shared key material: the master session key MSK (master session key) and the extended master session key EMSK (extended MSK;). The MSK is used to generate a shared session key between the MS and the BS.

Mobile WiMAX needs mobile communication services that support vehicle speed. In the process of MS mobility, it is inevitable to switch between BSs. The length of handover time seriously affects the communication quality of MS. Figure 1 shows the network authentication and authorization when mobile WiMAX users switch. The entire handover process involves five entities: mobile terminal MS, current serving BS, target BS, ASN-GW (Access Service Networks-Gateway), and P AAA server. The current IEEE 802.16m handover authentication method is: Before the MS handover, the service BS and the target BS re-execute a complete EAP authentication, and negotiate a new session key material between the MS and the target BS, such as PMK (Pairwise). Master Key, Paired Master Key), AK (Authorization Key), CMAC key (Cipher-based Message Authentication Code Key) and P TEK (Transmission Encryption Key) Key), etc., then perform the switch. However, the EAP authentication process itself is very time consuming, which increases the delay and reduces the efficiency. As a result, the quality of communication services is affected to varying degrees, especially for services with strong real-time requirements, such as VoIP and multimedia services. Seriously, users can feel the problem of a significant drop in service quality such as pauses and interruptions.

Therefore, in order to ensure the quality of mobile WiMAX network services and reduce handover delay, it is necessary to provide a fast handover authentication mechanism for mobile WiMAX networks. Summary of the invention

The object of the present invention is to provide a ticket-based EAP handover authentication method for a mobile WiMAX network, which can support fast handover in a high speed motion scenario.

To achieve the above objective, the technical solution of the present invention is: After the MS first accesses the mobile WiMAX network and successfully completes the EAP authentication with the AAA server, the access BS generates a resident identity similar to the resident identity using the multicast BS group key. The credit note of the certificate; when the MS needs to switch to a new BS due to the mobile, it only needs to provide its credit ticket to authenticate the identity of the target BS, thereby avoiding re-EAP authentication, thereby achieving secure fast handover.

The invention specifically includes the creation and distribution of MS credit notes and the use of MS credit notes.

The purpose of the creation and distribution of the MS credit ticket is to create a similar identity card for the MS by the access BS using its multicast BS group key after the MS first accesses the mobile WiMAX network and successfully completes the EAP authentication with the AAA server. The credit notes are distributed to the MS, so that the MS only needs to provide its credit card to the target BS when switching, and can quickly pass the identity authentication. The specific methods for creating and distributing MS credit notes are as follows:

1) After receiving the 256-bit MSK transmitted by the AAA server, the access BS extracts the last 128 bits of the MSK. As a temporary cipher-based message authentication code key (TCK); the access BS may also extract the first 128 bits of the MSK or 128 bits of other locations as the TCK;

2) The access BS uses the MGK (multi-BS group key) to encrypt the MAC (Media Access Control) address MSID, MSK, and ticket validity period T _exp of the MS to generate a credit note T. _MS , ie formula (1)

TMS = ENC _MGK (MSID, MSK, T _exp ) (1)

3) The access BS uses TCK to encrypt the message (G/AM^A^, H _SS ) to generate a ciphertext-based message authentication code.

CM AC, then add the generated CMAC code (GID'MSID ^ , T _MS , N _BS ) together as a ticket notification message Ticket_iss, as in formula (2)

Ticketjss^(GID SID _exp ^, N _BS )(CMAC _TCK )} (2) where GID is a multicast BS group identifier, and N _BS is a random number generated by the BS;

4) The access BS sends the ticket notification message Ticketjss directly to the MS;

5) After receiving the Ticketjss, the MS generates a TCK like the access BS (that is, the MS also extracts the last 128 bits in the MSK to generate the TCK), and then verifies the CMAC value in the Ticketjss. If the verification is correct, the MS sends a message to the access BS. The acknowledgement message ACK, if the verification is incorrect, sends a retransmission request to the access BS.

The purpose of using the MS credit ticket is that when the MS needs to switch to a new target BS in a multicast BS group to access the mobile WiMAX network, it only needs to send a handover request with its credit ticket to the target BS, which can be obtained quickly. The authentication of the target BS can avoid re-execution of time-consuming EAP authentication, thereby achieving fast handover. If the target BS to which the MS needs to be handed over is not a BS in the multicast BS group, the MS needs to perform EAP authentication again.

The specific method of using the MS credit note is as follows:

1) MS uses TCK to encrypt the message (G/AM^A S^A?^, ^^) to generate a ciphertext-based message authentication code.

CM AC, and then add the generated CMAC code together (G/AMWA S^AT^^N^) as the handover authentication request information THR_req, as in formula (3)

THR req = {(GID, MSID, BSID, T _MS , N _MS )(CMAC _TCK )} (3) where BSID is the MAC address of the BS, and N _MS is a random number generated by the MS;

2) The MS sends the handover authentication request information THR_req to the target BS;

3) After receiving the THR_req, the target BS verifies the validity of the handover authentication request by using the MGK. If it works, The target BS considers the MS to be legitimate and allows it to access the mobile WiMAX network, otherwise it refuses access. Further, the target BS specifically uses the following steps to verify the validity of the handover authentication request information THR_req:

1) the target BS checks THR_req GID, BSID and N _MS, BSID and see whether the GID coincides with itself and its N _MS N _MS whether the same record;

2) If the GID and consistent with its own BSID, and N _{_MS} N _MS their different records, the target BS using a decryption MGK T _MS, it is possible to obtain MSID, MSK T _exp, and other information;

3) target BS successfully decrypted T _MS, first check whether MSID and THR_req acquired decryption carried MSID agreement, if agreed, would continue to test T _exp, to determine whether the credit notes T _MS MS expired;

4) If the credit note T _{MS of the MS} has not expired, the target BS extracts 128 bits from the decrypted MSK as TCK, and uses TCK to encrypt (G/AMWASWA?^, ^^) in the THR_req message to generate a secret. The message authentication code CMAC is then compared with the CMAC value attached to the THR_req message to see if it is consistent;

5) If the CMAC values are consistent, the target BS considers the MS to be a legitimate user and accepts the MS's handover authentication request, allowing it to access the mobile WiMAX network. Compared with the prior art, the positive effects of the present invention are:

1) Switching the authentication framework is simple

The ticket-based fast EAP handover authentication method of the present invention only needs the target BS to verify the MS credit ticket by using the multicast BS group key MGK, so that the mutual authentication between the MS and the BS can be realized, and the entire handover authentication process does not need any other Third party participation (such as the previous service BS, AAA server, etc.).

2) Switching authentication speed is fast

When switching to a new BS, the original method requires re-execution of EAP authentication, and the EAP authentication process itself is very time consuming, which increases the handover delay. The fast switching authentication method of the invention can avoid time-consuming EAP authentication, and the verification of the MS credit ticket does not need to involve any third party, and the switching authentication process can be greatly accelerated, and the fast switching requirement in the case of the speed of the vehicle is met, and the real-time performance is met. The quality of the business is not affected. DRAWINGS

Figure 1 is a schematic diagram of network authentication and authorization when a mobile WiMAX user switches;

2 is a basic flowchart of the implementation of the ticket-based fast EAP handover authentication method of the present invention;

3 is an implementation example of a ticket-based fast EAP handover authentication method of the present invention. detailed description

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

As shown in FIG. 2, the basic flowchart of the implementation of the ticket-based fast EAP handover authentication method of the present invention includes the following steps:

Step 201: When the MS accesses the mobile WiMAX network for the first time, it performs complete EAP authentication by accessing the BS and the AAA server, and establishes a shared primary session key MSK with the AAA server;

Step 202: After receiving the MSK transmitted by the AAA server, the access BS creates a credit ticket T _MS for the MS by using the MGK, then creates a ticket notification message Ticket_iss, and sends the Ticketjss to the MS. After receiving the ticket notification message Ticketjss, the MS receives the ticket notification message Verifying the CMAC value in Ticketjss. If the verification is correct, the MS sends an acknowledgement message ACK to the access BS. If the verification is incorrect, a retransmission request is sent to the access BS.

Step 203: After successfully accessing the credit ticket T _MS to the MS, the access BS negotiates a session key such as a PMK, an AK, a CMAC key, and a TEK with the MS by using a session key agreement protocol defined in the IEEE 802.16 standard.

Step 204: When the MS needs to switch to the new BS to access the mobile WiMA network due to the mobile, the MS determines whether the target BS is a BS in the multicast BS group by checking the GID number broadcast by the target BS. If the target BS is a BS in the multicast group, the fast handover can be performed using the credit ticket T _MS , otherwise the EAP authentication needs to be performed again;

Step 205: If the target BS is a BS in the multicast group, the MS sends a fast handover authentication request including the credit ticket T _{MS to} the target BS, and after receiving the fast handover authentication request of the MS, the target BS decrypts and uses the corresponding MGK. Verification of the credit note of the MS. If the verification is passed, the target BS considers the MS to be a legitimate user;

Step 206: After successfully verifying the handover authentication request of the MS, the target BS negotiates a session key such as a PMK, an AK, a CMAC key, and a TEK with the MS using a session key agreement protocol defined in the IEEE 802.16 standard. The present invention can be applied to a mobile WiMA network, and is applicable not only to a next-generation mobile WiMAX (ie, IEEE 802.16m) network that is being developed, but also to all mobile WiMAX networks such as IEEE 802.16e-2005 and IEEE 802.16j-2009 that have been released. .

FIG. 3 is a specific implementation example of the ticket-based fast EAP handover authentication method in the IEEE 802.16m network environment. The working process of this implementation example is described as follows:

Step 301: When the MS accesses the IEEE 802.16m network for the first time, it performs complete EAP authentication with the AAA server, and establishes a shared primary session key MSK with the AAA server;

Step 302: The AAA server securely transmits the MSK to the BS ₁ by accessing the service network gateway ASN-GW _; Step 303: BSi uses the MGK to create a credit ticket T _{MS for the MS;}

Step 304: The BSi sends a notification message Ticketjss containing the credit ticket T _MS to the MS; Step 305: After receiving the Ticketjss, the MS uses the TCK to verify the correctness of the message. If the verification passes, the BSi sends an acknowledgement message ACK (the message can be omitted);

Step 306: The BSi sends a challenge message to the MS, CNONCE_BS;>, where NONCE_BS is a random number created;

Step 307: The MS generates a PMK, an AK, and a CM AC key by using a method defined by IEEE 802.16m.

Step 308: The MS sends a request message (MSID*, NONCE_BS, NONCE_MSXCMAC) to the BSi, where the MSID* is a change of the MAC address of the MS, and the NONCE_MS is a random number created by the MS;

Step 309: The BS generates a PMK, AK, and CM AC key by using a method defined by IEEE 802.16m, and then uses the CMAC key to verify the validity of the request message.

Step 310: The BSi sends a response message (NONCE_BS, NONCE_MS) (CMAC) to the MS.

Step 311: The MS generates a TEK by using a method defined by IEEE 802.16m.

Step 312: 88 ₁ generates a TEK by using a method defined by IEEE 802.16m;

Step 313: When the MS needs to switch to the new BS to access the mobile WiMA network due to the mobile, the MS checks whether the target BS is a BS in the multicast BS group by checking the GID number broadcast by the target BS. If the target BS is not a BS in the multicast group, EAP authentication needs to be performed again, otherwise the following steps are continued to perform fast switching;

Step 314: The MS sends a fast handover authentication request message THR_req to the BS ₂ , where the message includes the credit ticket TMS of the MS;

Step 315: BS ₂ BS using its multicast group key to decrypt MGK THR_req T and verify the validity of the _MS, if the verification is passed, the MS is considered legitimate user access request to and receive;

Step 316: BS ₂ sends a challenge message CNONCE_BS to the MS; >, where NONCE_BS is a random number created by BS ₂ ;

Step 317: The MS generates a PMK, AK, and CMAC key by using a method defined by IEEE 802.16m.

Step 318: The MS sends a request message (MSID*, NONCE_BS, NONCE_MSXCMAC) to the BS ₂ , where the MSID* is a transform of the MAC address of the MS, and the NONCE_MS is a random number created by the MS.

Step 319: BS ₂ generates a PMK, AK, and CMAC key by using a method defined by IEEE 802.16m, and then verifies the validity of the request message by using the CMAC key;

Step 320: BS ₂ sends a response message (NONCE_BS, NONCE_MS) (CMAC) to the MS;

Step 321: The MS generates a TEK by using a method defined by IEEE 802.16m;

Step 322: BS ₂ generates a TEK using a method defined by IEEE 802.16m.

Claims

Claim

A method for rapidly switching EAP authentication in a mobile WiMAX network, the steps of which are:

1) When the client accesses the mobile WiMA network for the first time, it performs EAP authentication with the EAP authentication server and establishes a primary session key MSK;

2) The access authenticator BS uses its multicast BS group key MGK to create a credit note T _{MS for the MS} and distributes it to the MS; the credit note includes: MS MAC address MSID, MSK, ticket validity period T _{exp ;}

3) when the MS switches to a target BS in the multicast BS group, send a handover request THR_req with its credit ticket to the target BS; the handover request THR_req includes: MAC address BSID of the target BS, MAC of the MS Address MSID, MS generated random number N _MS , multicast BS group identifier GID, credit ticket T _MS;

4) After receiving the THR_req, the target BS verifies the validity of the handover authentication request by using the MGK; if valid, the target BS considers the MS to be legal and allows it to access the mobile WiMAX network, otherwise it denies access.

2. The method according to claim 1, wherein the access authenticator BS encrypts the credit ticket, and generates a ticket notification message Ticketjss to send to the MS; wherein the ticket notification message is:

, CMAC _TCK is to use the key TCK to message

(GID SID ^ , T _m , N _BS ) A ciphertext-based message authentication code generated by encryption.

The method according to claim 2, wherein the key TCK is generated by extracting the last 128 bits of the main session key MSK as a temporary ciphertext-based message authentication code key TCK.

The method according to claim 2, characterized in that the key TCK is generated by extracting the first 128 bits of the main session key MSK as a temporary ciphertext-based message authentication code key TCK.

The method according to claim 2 or 3 or 4, wherein after receiving the Ticketjss, the MS verifies the CMAC value in the Ticketjss by using the generated key TCK, and if the verification is correct, the MS gives the access BS An acknowledgment message ACK is sent, and if the verification is incorrect, a retransmission request is sent to the access BS.

6. The method according to claim 2 or 3 or 4, characterized in that the method for generating the handover request THR_req is:

The MS encrypts the message (G/AMWA SWA?^, ^^) by using the key TCK to generate a ciphertext-based message authentication code.

CM AC, and then the generated CMAC code is added to (G/AMffi), SWA?^, W^) together as the switching authentication request information THR_req.

The method according to claim 6, wherein after the target BS receives the THR_req, the method for verifying the validity of the handover authentication request by using the MGK is:

1) The target BS checks whether the GID, BSID, and N _{MS in} THR_req correspond to its own GID, BSID, and N _MS Consistent

2) If the GID, BSID, BSID consistent with the GID itself, and its N _{_MS} N _MS recording different target BS using a decryption MGK T _MS, acquiring MSID, MSK, T _exp information;

3) target BS decrypt the T _MS, first check whether MSID and THR_req acquired decryption carried MSID agreement, if agreed, would continue to test T _exp, to determine whether the credit notes T _MS MS expired;

4) generated based on the encrypted message if the MS ciphertext credit notes _MS T has not expired, the target BS generates a key TCK, TCK and use of message THR_ _re q _{{GID'MSID, BSID, T m,} N MS) for The authentication code CMAC is then compared with the CMAC value attached to the THR_req message to see if it is consistent;

5) If the CMAC value is consistent, the target BS accepts the handover authentication request of the MS, otherwise the handover authentication request is invalid.

The method according to claim 1 or 2 or 3 or 4, wherein the EAP authentication server securely transmits the MSK to the access authenticator BS by accessing the service network gateway.

9. The method of claim 1 or 2 or 3 or 4, wherein the mobile WiMAX network comprises: an IEEE 802.16m mobile WiMAX network, an IEEE 802.16e-2005 mobile WiMAX network, and an IEEE 802.16j-2009 mobile WiMAX The internet.