Abstract:
In a wireless communication system including an access terminal operating based on a hierarchical protocol stack requiring registration for each of individual layers and/or services, a base station providing a wireless access service to the access terminal, and network elements required for performing the registration for each of individual layers and/or services with respect to the access terminal, a comprehensive registration method is provided where the access terminal transmitting to the base station or requesting from the network parameters required for the access terminal to register in at least one layer and service, and the a base station transmits to the corresponding network elements parameters required for the access terminal to register in the at least one layer and/or service and receiving the parameters from the network elements. The access terminal is registered in the at least one layer and/or service depending on the collected parameters. Redundant procedures in the registration of individual layers and/or services are reduced by considering characteristics of the respective layers and/or services, thereby enabling seamless handover as well as fast service.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION 
     This application claims the benefit under 35 U.S.C. §119(a) of a Korean Patent Application No. 2006-20488 filed on Mar. 3, 2006 in the Korean Intellectual Property Office and Korean Patent Application Serial No. 2006-82155 filed on Aug. 29, 2006 in the Korean Intellectual Property Office, the entire disclosure of both applications is hereby incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a method for wireless communication system. More particularly, the present invention relates to a method for comprehensive registration that simplifies registration procedures for individual layers and/or services in an All-IP based wireless communication network. 
     2. Description of the Related Art 
     With the development of the Internet and mobile communication technologies, the quantity of wireless data traffic has recently surpassed voice traffic, so much so that the core of information communication is shifting from voice services to packet services. Also, international standardization organizations, focusing on a third generation partnership project (3GPP) and a 3GPP2, have introduced All-IP network concepts and are standardizing the All-IP networks. Essentially, the All-IP network is a next-generation mobile communication network providing real-time and/or non-real-time multimedia services, including voice, image and data, based on an Internet protocol (IP). An All-IP network enables seamless IP-based services irrespective of wireless access methods, real-time and non-real-time multimedia services for voice, images and data, to be provided simultaneously and efficiently sending information by utilizing packet technologies. An All-IP network integrates all services into an IP-based transfer network, thereby providing communication network carriers with an opportunity to economically and efficiently establish a communication network. 
     However, since a cellular mobile network and an IP network each have their own independent registration procedures for individual layers and/or services, a method for registration suitable for the All-IP network is required as mobile networks evolve into All-IP networks. Traditionally, conventional wireless access networks may require a registration procedure when a wireless link access is established and a Mobile IP (MIP) may require a registration procedure to support macro mobility. Additionally, third generation (3G) networks basically support registration of a session initiation protocol (SIP) to effectuate a session control. 
     It is expected that a next-generation All IP mobile network will basically provide not only registration for wireless link access but also the MIP and SIP services. If the current registration procedure for each of individual layers and/or services is implemented whenever it is needed in the All-IP network, process latency will unavoidably occur due to redundancy in each layer and/or service and the procedural complexity. 
     Accordingly, there is a need for a comprehensive registration method that simplifies registration procedures for individual layers and/or services in an All-IP based wireless communication network, which can avoid redundancy in each layer and/or service and the procedural complexity. 
     SUMMARY OF THE INVENTION 
     Exemplary embodiments of the present invention address at least the above problems and/or disadvantages and provide at least the advantages described below. Accordingly, an aspect of exemplary embodiments of the present invention is to provide a comprehensive registration method capable of providing seamless handover as well as fast services and reducing overhead on a wireless link by reducing redundant procedures in the registration for each of individual layers and/or services. 
     Another aspect of exemplary embodiments of the present invention is to provide a method for comprehensive registration in which an access terminal (AT) sends and collects in advance, information required for registration of an upper layer and/or service in an L 2  registration procedure for wireless link access, thereby minimizing registration time. 
     Another aspect of exemplary embodiments of the present invention is to provide a comprehensive registration method in which in an L 2  registration procedure and information items required for registration of multiple layers are collected and stored as a mobility context table in a wireless access system, such as a base station (BS) and when a handover is detected, information items required for each layer are combined and transmitted, and thus fast registration and handover can be supported. 
     Another aspect of exemplary embodiments of the present invention is to provided a comprehensive registration method in a wireless communication system including an access terminal operating based on a hierarchical protocol stack requiring registration for each of individual layers and/or services, a base station providing a wireless access service to the access terminal and network elements required for performing the registration for each individual layer and/or services with respect to the access terminal. The comprehensive registration method comprises the access terminal transmitting to the base station or requesting from the network parameters required for the access terminal to register in at least one layer and service, the base station transmitting to the corresponding network elements parameters required for the access terminal to register in at least one layer and/or service and receiving the parameters from the network elements and by using the collected parameters, registering the access terminal in the at least one layer and/or service. 
     Another aspect of exemplary embodiments of the present invention is to provide acomprehensive registration method for a base station in a wireless communication system including an access terminal operating based on a hierarchical protocol stack requiring registration for each of individual layers and/or services, the base station providing a wireless access service to the access terminal and network elements required for performing the registration for each of individual layers and/or services with respect to the access terminal. The exemplary comprehensive registration method includes receiving parameters required for the access terminal to register in at least one layer and service and a request for the parameters from the access terminal, transmitting the parameters required for the access terminal to register in at least one layer and/or service to the corresponding network elements and receiving the parameters from the network elements and by using the collected parameters, registering the access terminal in at least one layer and/or service. 
     Another aspect of exemplary embodiments of the present invention provides a comprehensive registration method for an access terminal in a wireless communication system including the access terminal operating based on a hierarchical protocol stack requiring registration for each of individual layers and/or services, a base station providing a wireless access service to the access terminal and network elements required for performing the registration for each of individual layers and/or services with respect to the access terminal. The comprehensive registration method includes transmitting to the base station or requesting from the network parameters required for the access terminal to register in at least one layer and service and the base station transmitting to the corresponding network elements parameters required for registration in each layer and service, and receiving the parameters from the network elements, and waiting to perform registration of the access terminal in the corresponding layer and service by using the collected parameters. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other exemplary features and advantages of certain exemplary embodiments of the present invention will become more apparent from the following detailed description of certain exemplary embodiments thereof when taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a diagram illustrating a comprehensive method registration of an All-IP network with registration procedures according to an exemplary embodiment of the present invention; 
         FIGS. 2A through 2C  illustrate binding tables stored in a base station (BS), a home agent (HA) and session initiation protocol (SIP) registers, respectively, according to an exemplary embodiment of the present invention; 
         FIG. 3  is a message flowchart illustrating a comprehensive registration method in an All-IP network according to an exemplary embodiment of the present invention; and 
         FIG. 4  is a message flowchart illustrating a comprehensive registration method in an All-IP network when a handover is performed according to an exemplary embodiment of the present invention. 
     
    
    
     Throughout the drawings, like reference numerals will be understood to refer to like elements, features and structures. 
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The matters exemplified in this description are provided to assist in a comprehensive understanding of various exemplary embodiments of the present invention disclosed with reference to the accompanying figures. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the exemplary embodiments described herein can be made without departing from the scope and spirit of the claimed invention. Also, descriptions of well-known functions and constructions are omitted for clarity and conciseness. 
       FIG. 1  is a diagram illustrating a method for comprehensive registration of an All-IP network with registration procedures according to an exemplary embodiment of the present invention. The registration procedures for individual layers and/or services will be described independently for L 2 , Mobile IP (MIP), and session initiation protocol (SIP) services, by way of example. For example, when the power is turned on, an access terminal (AT)  10  performs initialization or examines a system and activates a link through a link registration procedure with a base station (BS)  13 . In this procedure, the AT  10  performs an authentication procedure with an authentication server  15 . When the link registration procedure with the BS  13  is completed, a radio bearer is activated and the BS  13  generates a link ID table. After finishing the link registration procedure, the AT  10  establishes a care-of address (CoA) through communication with an access router (AR) or a gateway (GW)  17  connected to the BS  13 , searches for a home agent (HA)  19  or receives an HA address through a dynamic host configuration protocol (DHCP) server  21 . When the HA address is acquired, the AT  10  accesses the HA  19  and makes an entry of its CoA in an MIP binding table, thereby completing the MIP registration. In this exemplary procedure, for a secure connection between the AT  10  and the HA  19 , the AT  10  performs an authentication procedure with an authentication server  15  as in the link registration procedure. 
     When the MIP registration is completed, the AT  10  searches for an SIP proxy  22  or acquires the address of the SIP proxy  22  through the DHCP server  21 , and makes an entry of the current location of the AT  10  in a binding table in an SIP register  23 . In this procedure, for a secure connection between the AT  10  and the proxy  22  and between the proxy  22  and the register  23 , the AT  10  and the SIP servers perform authentication procedures with the authentication server  15 . 
       FIGS. 2A through 2C  illustrate binding tables stored in a base station BS, an HA, and SIP registers, respectively, according to an exemplary embodiment of the present invention. An L 2  binding table illustrated in  FIG. 2A  includes media access control (MAC) address, connection ID (CID) and lifetime fields of an AT. An IP address binding table illustrated in  FIG. 2B  includes HoA, CoA and lifetime fields. A SIP address binding table illustrated in  FIG. 2C  includes user uniform resource identifier (URI), current URI and lifetime fields. 
     As described above, an AT needs to register in each layer and services and information items required for the AT to register in each layer and services are different from each other. 
       FIG. 3  is a message flowchart illustrating a comprehensive registration method in an All-IP network according to an exemplary embodiment of the present invention. First, when the power is turned on, an AT  30  performs an initial ranging procedure, S 301 , and if the initial ranging procedure is successfully completed, an BS  311  generates a CoA unique to the AT  30 , S 302 . In a case where the BS  311  does not support generation of a CoA, S 302 , the generation of a CoA is performed, S 315 . If the generation of a CoA is completed, the AT  30  and the BS  311  perform negotiation of basic capabilities at a link layer to determine an L 2  key management protocol, an authentication policy, an MAC mode, and so on, S 303 . 
     If the L 2  key management protocol, the authentication policy, the MAC mode, and so on are thus determined, local challenge information and an EAP request message requesting a user ID are sent to the AT  30  using an extensible authentication protocol (EAP), S 311 . In response to this, the AT  30  sends an EAP response message including its own user ID, to the BS  311 , S 312 . 
     After the EAP response message from the AT  30  is received, the BS  311  generates a set of coupled registration parameters for an All-IP mobile network basic service with the user ID and network prefix information, and thus generates an initial registration parameter list and a mobile content table (MCT), S 313 . The initial registration parameter list includes the user ID, CoA, tempURL and the like. If generation of a CoA, S 302 , is not supported, the CoA is expressed as null (or the CoA is nullified). The MCT is formed with an initial registration parameter list value at its initial stage. 
     When the initial registration parameter list and the MCT are generated, the BS  311  generates an authentication request message using the parameters and embedded binding information containing binding update (BU) and a SIP register, and sends the message to an authentication server  322 ; S 314 . The authentication request message may include user ID information, binding information, a proxy address, and an upper layer registration server address. In a case where the proxy address and the upper layer registration server address are not known, the authentication request message may also include requests for these addresses. 
     When the authentication request message is received, the authentication server  322  generates a session key, and selects an HA  323 , and an SIP register  321  as upper layer basic service registration servers, S 315 . If generation of a CoA, S 302 , is not supported, the authentication server  322  acquires a CoA and generates a CoA, S 315 . Then, the authentication server  322  sends a binding message to the HA  323  and the SIP register  321  on behalf of the AT  30 , and generates authentication data information, S 316  and S 317 . Based on the SIP binding information and the authentication data information, the SIP register  321  sends authentication information to a SIP proxy  315 , S 330 . Based on the authentication data information and information items collected from the HA  323  and the SIP register  321 , the authentication server  322  sends an authentication response message as a response to the authentication request message, to the BS  311 , S 331 . The authentication response message includes binding acknowledge (BA), authentication information, a registration server address, a proxy address, and key information. When the authentication response message is received, the BS  311  copies upper layer registration related information, including an upper layer user ID, upper layer registration server addresses, the proxy server address, and the session key, in the MCT, thereby updating the MCT in step S 318 . 
     After updating the MCT, the BS  311  can send an EAP success message to the AT  30 , thereby notifying the AT that the subscriber authentication is completed, S 319 . If the subscriber authentication is completed, the AT  30  and the BS  311  establishes L 2  security association on a wireless link, S 320 , and complete the L 2  registration by exchanging messages, step S 321 . Then, the BS  311  sends an authentication response message to the AT  30 , thereby completing the MIP registration, and sending SIP proxy and authentication information, S 322 . If the MIP registration is completed, the AT  30  sends an SIP registration message to the SIP register  321  through an SIP proxy  313 , and thus completes the SIP registration in step S 323 . Meanwhile, the SIP register  321  receives the SIP registration message from the AT  30 , performs authentication, and confirms SIP binding information, S 324 . 
     In steps S 340  and S 341 , upper layer and/or service registration messages, (for example an MIP registration message and an SIP registration message), are sent periodically according to a value determined by the BS  311 , not by the AT  30 . In  FIG. 3 , the dotted lines are used to indicate functions that may be logically separate from each other but can be integrated and implemented together. 
       FIG. 4  is a message flowchart illustrating acomprehensive registration method in an All-IP network when a handover is performed according to another exemplary embodiment of the present invention. For example, when a handover (HO) is detected, an old BS  411  to which an AT  30  is connected, identifies the range of a coupled registration, by identifying a layer where the HO occurs. Then, the old BS  411  generates a set of parameters to be loaded on a context transmission message from an MCT, S 401 , and transmits the set to a new BS  412 , S 411 . If the context transmission message is received, the new BS  412  generates a MCT based on the message, and identifies a HO of which layer will occur, S 413 . If the layer in which the HO will occur is identified, the new BS  412  generates an authentication request message including coupled registration information before L 2  activation, S 415 . In a case where upper layer registration should be performed, the binding information of the authentication request message includes an embedded BU and SIP register message. 
     The new BS  412  sends the authentication request message to an authentication server on behalf of the AT  30  before L 2  activation, S 417 . If the authentication request message is received, the authentication server  322  generates a common key, performs a registration procedure with respect to the layer in which the HO will occur, and sends an authentication response message to the new BS  412 , S 419 . 
     When the authentication response message is received, if initial ranging with the AT  30  is completed, the new BS  412  updates the MCT using information acquired through the authentication response message, S 420 , and sends an EAP success message to the AT  30 , thereby notifying the AT that subscriber authentication is successfully completed, S 421 . 
     If the initial ranging, S 431 , with the AT  30  is not completed, the new BS  412  waits until the initial ranging is successfully completed, and then notifies the AT that subscriber authentication is successfully complete, S 421 . 
     If the subscriber authentication is completed, the new BS  412  and the AT  30  perform L 2  registration, S 423 , and if an upper layer HO occurs (MIP or/and SIP HO), MIP registration and SIP registration are performed, S 425 . This procedure is similar to the exemplary procedure illustrated in  FIG. 3 . 
     Though the MIP and SIP registration services are described as basic capabilities provided by the comprehensive registration method according to exemplary embodiments of the present invention, registration for other functionalities or services can also be comprehended in the comprehensive registration method according to exemplary embodiments of the present invention. 
     According to a comprehensive registration method of the present invention as described in the exemplary embodiments above, redundant procedures in the registration of individual layers and/or services can be reduced by considering characteristics of the respective layers and/or services, thereby enabling seamless handover as well as fast service. Also, overhead on a wireless link can be reduced. 
     Furthermore, according to a comprehensive registration method of the present invention as described in the exemplary embodiments above, in a L 2  registration procedure for establishing a wireless link access, an AT can send and collect in advance information items required for upper layer/service registration, thereby minimizing a registration time. 
     Additionally, according to a comprehensive registration method of the present invention as described in the exemplary embodiments above, in an L 2  registration procedure, information items required to perform registration of multiple layers can be transmitted, collected and stored as an MCT in a wireless access system, such as an AN, and when an HO is detected, information items required for each layer are combined and transmitted and thus fast registration and handover can be supported. 
     The above-described exemplary embodiments of a comprehensive registration method may be recorded in computer-readable media including program instructions to implement various operations embodied by a computer. The media may also include, alone or in combination with the program instructions, data files, data structures, and the like. The media and program instructions may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD ROM disks and DVD; magneto-optical media such as optical disks; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory, and the like. Examples of program instructions include both machine code, such as produced by a compiler, and files containing higher level code that may be executed by the computer using an interpreter. The described hardware devices may be configured to act as one or more software modules in order to perform the operations of the above-described embodiments of the present invention. 
     While the present invention has been shown and described with reference to certain exemplary embodiments as defined by the appended claims and their equivalent. It is to be appreciated that those skilled in the art can change or modify the exemplary embodiments without departing from the scope of the invention.