Method for IP management connection control in wireless communication system

This application claims priority to and the benefit of Korean Patent Application No. 10-2006-0120816 filed in the Korean Intellectual Property Office on Dec. 1, 2006, and No. 10-2007-0096615 filed in the Korean Intellectual Property Office on Sep. 21, 2007, the entire contents of which are incorporated herein by reference.

(a) Field of the Invention

The present invention relates to a connection control method for managing Internet protocol in a communication system.

(b) Description of the Related Art

A high-speed portable Internet (HPi) system is a 3.5 th generation mobile communication system in which a wireless transmission method for guaranteeing spectrum usage efficiency in the 2.3 GHz frequency bandwidth is used to provide images of various Internet protocol (IP)-based wireless data services (e.g., streaming video, file transfer protocol (FTP), email, and chatting services) and perform high-speed packet data transmission.

It is required to allocate an IP address to an authenticated access terminal to connect to the Internet through a mobile communication system, and the access terminal connects to the Internet by using the allocated IP address to receive various services.

Methods for allocating the IP address to the access terminal include a static IP address allocation method and a dynamic IP address allocation method.

In the static IP address allocation method, the IP address allocated to the access terminal is used, and an IP managing message for allocating the IP address is not used. Accordingly, a connection establishment process for transmitting the IP managing message is not required. However, in this static IP address allocation method, when the access terminal leaves a coverage area of a subnet that allocated the IP address to the access terminal, IP address reallocation between subnets is not supported. Accordingly, the static IP address allocation method has mobility limitation in the mobile communication system in which the access terminal moves from a cell to another cell.

In the dynamic IP address allocation method, when the access terminal moves from a cell to another cell, a roaming or handover operation is performed to guarantee inter-cell mobility. That is, when the access terminal leaves a coverage area of a corresponding subnet, an IP address is reestablished based on a dynamic host configuration protocol to provide a roaming service to the access terminal, or a handover operation by mobile IP registration using care-of-address (CoA) is performed to continuously provide a mobile communication service.

However, in this wireless communication system, a secondary management connection is established to allocate an IP address to an access terminal connected to the system, traffic may not be transferred but the IP managing message may be transmitted through this secondary management connection, and additional connection is required to be established for traffic data transmission.

Accordingly, access point (AP) resources including transport connection ID and service flow may be wasted.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

The present invention has been made in an effort to provide an Internet protocol (IP) management connection controlling method and device for efficiently using resources of an access point.

According to an exemplary embodiment of the present invention, in an IP management connection controlling method in an access point of a mobile communication system, a first traffic connection is established to a packet access router, uplink and downlink second traffic connections are established to an access terminal, and an IP management message is transmitted through the first traffic connection and the second traffic connection.

According to another exemplary embodiment of the present invention, in an IP management connection control method of an access point of a mobile communication system, initial ranging of an access terminal is established, basic transport capability of the access terminal is established, the access terminal is authenticated, an authentication key is exchanged, the access terminal is registered, an uplink traffic connection and a downlink traffic connection to the access terminal are established, an IP management message is transmitted through the uplink traffic connection and the downlink traffic connection, and an IP address is allocated.

As described, according to the exemplary embodiments of the present invention, an auxiliary management connection is not used for transmission of an IP management message from an access point to an access terminal, a transport connection for transmitting an IP management message packet and a traffic packet is established, and therefore resources of the access point may be efficiently used without establishing an additional connection.

FIG. 1 is a schematic diagram of a mobile communication system according to an exemplary embodiment of the present invention.

FIG. 2 is a flowchart representing an IP management connection controlling method according to the exemplary embodiment of the present invention.

FIG. 3 is a diagram representing a flow of messages of the IP management connection controlling method according to the exemplary embodiment of the present invention.

FIG. 4 is a flowchart representing an initial process of the IP management connection controlling method according to the exemplary embodiment of the present invention.

FIG. 5 is a flowchart representing a traffic connection process between an access point and a PAR in the exemplary embodiment of the present invention.

FIG. 6 is a flowchart representing a traffic connection process between the access point and an access terminal in the exemplary embodiment of the present invention.

FIG. 7 is a flowchart representing an IP address allocation process according to the exemplary embodiment of the present invention.

In the following detailed description, only certain exemplary embodiments of the present invention have been shown and described, simply by way of illustration. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive. Like reference numerals designate like elements throughout the specification.

In addition, unless explicitly described to the contrary, the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. The terms “unit”, “module”, and “block” used herein mean one unit that processes a specific function or operation, and may be implemented by hardware, software, or a combination thereof.

An Internet protocol (IP) management connection controlling method according to an exemplary embodiment of the present invention will now be described.

FIG. 1 is a schematic diagram of a mobile communication system according to the exemplary embodiment of the present invention.

As shown in FIG. 1 , the mobile communication system according to the exemplary embodiment of the present invention includes an access terminal (AT) 100 , an access point (AP) 200 , and a packet access router (PAR) 300 .

The access point 200 is connected to the access terminal 100 to support wireless access and network connection of the access terminal 100 .

The access point 200 includes a radio frequency subsystem 210 , an access traffic subsystem (ATS) 220 , an access controlling subsystem (ACS) 230 , and an ethernet switch 240 .

The radio frequency subsystem 210 wirelessly transmits and receives data.

The access traffic subsystem 220 performs traffic processes, a packet scheduling operation, a wireless link controlling operation, a radio resource managing operation, a packet matching operation between wired and wireless links, and a hybrid automatic repeat request (HARQ) controlling operation. The access traffic subsystem 220 along with the access controlling subsystem 230 and radio frequency subsystem 210 performs traffic processes and wireless link transmitting/receiving control operations.

The access traffic subsystem 220 receives cell information and user connection information from the access controlling subsystem 230 , performs traffic processes and a scheduling function, and transmits a scheduled downlink data combination to a radio frequency device to request radio link transmission, or processes a received uplink data combination to transmit it to the PAR 300 .

The access controlling subsystem 230 controls a protocol operation for controlling the access point 200 and the access terminal 100 , and manages users and cells.

The PAR 300 connected to the access point 200 based on IP controls mobility of the access terminal 100 connected to the access point 200 , performs a packet routing function, and is connected to the Internet to access an IP-based wired core network. In addition, the PAR 300 is connected to an authentication server, a home agent (HA), and an address allocation server to perform an authentication function, a dynamic host configuration protocol (DHCP) function, a mobile IP (MIP) function, a handover function between access points, and a handover control function between the PARs 300 .

The IP management connection controlling method according to the exemplary embodiment of the present invention will now be described with reference to FIG. 2 and FIG. 3 .

FIG. 2 is a flowchart representing the IP management connection controlling method according to the exemplary embodiment of the present invention, and FIG. 3 is a diagram representing a flow of messages of the IP management connection controlling method according to the exemplary embodiment of the present invention.

Firstly, the access point 200 establishes initial ranging in step S 210 . As shown in FIG. 3 , when receiving a ranging request (hereinafter referred to as “RNG-REQ”) message 301 from the access terminal 100 desiring to receive an IP address, the access point 200 establishes the initial ranging between the access terminal 100 and the access point 200 and transmits a ranging response (hereinafter referred to as “RNG-RSP”) message 302 to the access terminal 100 .

The access point 200 establishes subscriber station basic capability in step S 220 . As shown in FIG. 3 , when receiving a subscriber station basic capability request (hereinafter referred to as “SBC-REQ”) message 303 from the access terminal 100 , the access point 200 establishes the subscriber station basic capability and transmits a subscriber station basic capability response (hereinafter referred to as “SBC-RSP”) message 304 to the access terminal 100 .

The access point 200 performs access terminal authentication and authentication key exchange in step S 230 . As shown in FIG. 3 , when receiving a privacy key management request (hereinafter referred to as “PKM-REQ”) message 305 from the access terminal 100 , the access point 200 transmits an authorization direct transfer command (hereinafter referred to as “ADTcmd”) message 306 to the PAR 300 , the PAR 300 transmits a diameter extensible authentication protocol (EAP) request [EAP-Start] (hereinafter referred to as “DER[EAP-Start]”) message 307 to an authentication server, and the authentication server performs user authentication and transmits a diameter EAP request [EAP-Success] (hereinafter referred to as “DER[EAP-Success]”) message 308 to the PAR 300 . The PAR 300 transmits the ADTcmd message 309 to the access point 200 , and the access point 200 transmits a privacy key management response (hereinafter referred to as “PKM-RSP”) message 310 to the access terminal 100 .

When the access terminal 100 receives the PKM-RSP message and transmits an authentication key request PKM-REQ[Key Request] message 311 to the access point 200 , the access point 200 allocates an authentication key response PKM-RSP[Key Reply] message 312 to the access terminal 100 to allocate an authentication key.

Subsequently, the access point 200 resisters an access terminal in step S 240 . As shown in FIG. 3 , when receiving a registration request (hereinafter referred to as “REG-REQ”) message 313 from the access terminal 100 , the access point 200 transmits a registration request (hereinafter referred to as “REGreq”) message 314 to the PAR 300 . When the PAR 300 registers a user and transmits a registration response (hereinafter referred to as “REQrsp”) message 315 to the access point 200 , the access point 200 transmits a registration response (hereinafter referred to as “REQ-RES”) message 316 to the access terminal 100 .

When registering the access terminal, the access point 200 establishes uplink and downlink traffic connections in step S 250 . The access point 200 firstly establishes traffic connection to the PAR 300 , and establishes the uplink and downlink traffic connections to the access terminal 100 .

As shown in FIG. 3 , when transmitting a dynamic service addition request (hereinafter referred to as “DSAreq”) message 317 to the PAR 300 and receiving a dynamic service addition response (hereinafter referred to as “DSAres”) message 318 from the PAR 300 , the access point 200 transmits a dynamic service addition request (hereinafter referred to as “DSA-REQ”) message 319 to the access terminal 100 . When receiving a dynamic service addition response (hereinafter referred to as “DSA-RSP”) message 320 from the access terminal 100 , the access point 200 transmits a dynamic service addition acknowledgement (hereinafter referred to as “DSA-ACK”) message 321 to the access terminal 100 , and transmits a dynamic service addition acknowledgement (hereinafter referred to as “DSAack”) message 322 to the PAR 300 .

Subsequently, the access point 200 allocates an IP address to the access terminal 100 in step S 260 . As shown in FIG. 3 , the access point 200 transmits the DSAack message to the PAR 300 , and operates in an IP address allocation waiting mode. When the access point 200 in the IP address allocation waiting mode receives an IP direct transfer command (hereinafter IDTcmd”) message 323 from the PAR, the access point 200 unpacks the IDTcmd message to identify IP allocation, and transmits a downlink transport connection identifier (hereinafter referred to as “DL Transport CID”) message 324 to the access terminal 100 .

When the access point 200 in the IP address allocation waiting mode receives an uplink transport connection identifier (hereinafter referred to as “DL transport CID”) message 325 from the access terminal 100 , the access point 200 transmits an IDTcmd[RRQ(Registration Request)] message 326 to the PAR 300 , receives an IDTcmd[RRP(Registration Reply)] message 327 from the PAR 300 , and transmits the DL Transport CID message 328 to the access terminal 100 .

An initial process of the IP management connection controlling according to the exemplary embodiment of the present invention will now be described with reference to FIG. 4 . FIG. 4 is a flowchart representing the initial process of the IP management connection controlling according to the exemplary embodiment of the present invention.

As shown in FIG. 4 , the access point 200 transmits the REGreq message to the PAR 300 , and operates in a REGrsp message waiting mode in step S 401 . When the access point 200 in the REGrsp message waiting mode receives the REGrsp message from the PAR 300 in step S 402 , the access point 200 cancels an operating response timer in step S 403 , and checks a response field of the received REGrsp message to identify a registration result for the access terminal 100 in step S 404 .

When failing in the registration for the access terminal 100 , the access point 200 transmits the REG-RSP message including a response field indicating a failure of user registration to the access terminal 100 in step S 413 , and performs a registration cancel process in steps S 417 and S 418 . When succeeding in the registration for the access terminal 100 , the access point 200 transmits the REG-RSP informing of success of the user registration to the access terminal 100 in step S 405 .

The access point 200 allocates a service class name for uplink and downlink IP management connections from system information to start the IP management connection process in step S 406 , allocates traffic parameters including a maximum traffic transmission speed designated to a service class in step S 407 , allocates convergence sublayer (CS) parameters including a packet classification principle in step S 408 , and establishes uplink and downlink transport connection identifiers (hereinafter referred to as “Transport CID”) for traffic transmission in step S 215 .

Here, the system information is stored and managed in predetermined constituent elements of the access point 200 , which is well known to a person of ordinary skill in the art, and therefore detailed descriptions thereof will be omitted.

The access point 200 transmits the DSAreq message including allocated information to the PAR 300 in step S 410 , operates a response timer in step S 411 , and changes a mode to a DSArsp message waiting mode for awaiting the DSArsp message from the PAR 300 in step S 412 .

When the access point 200 in the REGrsp message waiting mode in step S 401 receives a deregistration request (hereinafter referred to as “DREG-REQ”) message from the access terminal 100 in step S 414 , the access point 200 cancels the operating timer in step S 415 , and performs a deregistration process in steps S 417 and S 418 .

In addition, when the access point 200 in the REGrsp message waiting mode in step S 401 receives a timer finish request in step S 416 because of abnormal conditions including no response for the registration request from the PAR 300 , the access point 200 performs the deregistration process in steps S 417 and S 418 .

A traffic connection process between the access point and the PAR in the IP connection management controlling method according to the exemplary embodiment of the present invention will now be described with reference to FIG. 5 . FIG. 5 is a flowchart representing a traffic connection process between the access point and the PAR in the exemplary embodiment of the present invention.

As shown in FIG. 5 , when the access point 200 in the DSArsp message waiting mode in step S 501 receives the DSArsp message from the PAR 300 in step S 502 , the access point 200 cancels the operating timer in step S 503 , and checks the received message to identify the DSA connection of the PAR 300 in step S 504 .

When failing the DSA connection to the PAR 300 , the access point 200 transmits the DSAack message including an identification code informing of the failure to the PAR 300 , and performs a deregistration process in steps S 514 and S 515 .

When succeeding in the DSA connection to the PAR 300 , the access point 200 allocates an uplink and downlink service flow identifier received from the PAR 300 in step S 505 , allocates traffic parameters in step S 506 , and transmits the DSA-REQ message including service flow information including the uplink and downlink service flow identifier, the downlink and uplink Transport CID, and the traffic parameters to the access terminal 100 in step S 507 . In addition, the access point 200 operates the response timer in step S 508 , and changes a mode to a DSA-RSP message waiting mode in step S 509 .

When the access point 200 in the DSArsp message waiting mode in step S 501 receives the DREG-REQ message requesting connection cancellation from the access terminal 100 in step S 511 , the access point 200 cancels the operating timer for the response message in step S 512 , and performs the deregistration process in steps S 514 and S 515 .

In addition, when the access point 200 in the DSArsp message waiting mode in step S 501 receives a time finish request in step S 513 because of abnormal conditions including no response from the PAR 300 , the access point 200 performs the deregistration process in steps S 514 and S 515 .

A traffic connection process between the access point and the access terminal in the IP management connection controlling method according to the exemplary embodiment of the present invention will now be described with reference to FIG. 6

FIG. 6 is a flowchart representing a traffic connection process between the access point and the access terminal in the exemplary embodiment of the present invention.

As shown in FIG. 6 , when the access point 200 in the DSA-RSP message waiting mode in step S 601 receives the DSA-RS message in step S 602 , the access point 200 cancels the operating response timer in step S 603 , and checks the received message to identify DSA connection of the access terminal 100 in step S 604 . When failing in the DSA connection of the access terminal 100 , the access point 200 transmits the DSA-ACK message including an identification code informing the failure to the access terminal 100 in step S 609 , and performs the deregistration process in steps S 613 and S 614 .

When succeeding in the DSA connection of the access terminal 100 , the access point 200 transmits the DSA-ACK message including an identification code informing of the success to the access terminal 100 in step S 605 , and transmits the DSAack message including the identification code informing of the success to the PAR 300 in step S 607 . In addition, the access point 200 operates a timer that is allowed to perform IP address allocation of the access terminal 100 in step S 607 , and changes a mode to an IP address allocation waiting mode in step S 608 .

When the access point 200 in the DSA-RSP message waiting mode in step S 601 receives the DREG-REQ message for requesting connection cancellation from the access terminal 100 in step S 610 , the access point 200 cancels the operating response timer in step S 611 , and performs the deregistration process in steps S 613 and S 614 .

When the access point 200 in the DSA-RSP message waiting mode in step S 601 receives a timer finish request in step S 612 because of abnormal conditions including no response from the access terminal 100 , the access point 200 performs the deregistration process in steps S 613 and S 614 .

An IP address allocation process in the IP management connection controlling method according to the exemplary embodiment of the present invention will now be described with reference to FIG. 7 . FIG. 7 is a flowchart representing an IP address allocation process according to the exemplary embodiment of the present invention.

As shown in FIG. 7 , when the access point 200 in the IP address allocation waiting mode in step S 701 receives the IDTcmd message from the PAR 300 in step S 702 , the access point 200 unpacks the IDTcmd message in step S 703 , and identifies IP allocation from information included in a payload of the IDTcmd message in step S 704 .

When the access point 200 does not identify the IP address allocation from the payload, the access point 200 forms a traffic data packet by the DL Transport CID message in step S 709 , transmits the traffic data packet to the access terminal 100 in step S 710 , and maintains the IP address allocation waiting mode in step S 715 .

When the access point 200 identifies the IP address allocation from the payload, the access point 200 forms the traffic data packet by the DL Transport CID message in step S 705 , transmit the traffic data packet to the access terminal 100 in step S 706 , cancels the operating response timer in step S 707 , and changes the mode to a registration mode for receiving traffic connection establishment of the access terminal in which IP connection is completed in step S 708 .

When the access point 200 in the IP address allocation waiting mode in step S 701 receives the traffic data packet through the UL Transport CID message from the access terminal 100 in step S 711 , the access point 200 unpacks the UL Transport CID message in step S 712 , forms the IDTcmd message having the payload that is the traffic data packet transmitted as the UL Transport CID message in step S 713 , transmits the formed IDTcmd message to the PAR 300 in step S 714 , and maintains the current IP address allocation waiting mode in step S 715 .

When the access point 200 in the IP address allocation waiting mode in step S 701 receives the DREG-REQ message for requesting connection cancellation from the access terminal 100 in step S 716 , the access point 200 cancels the operating response timer in step S 717 , and performs the deregistration process in steps S 719 and S 720 .

When the access point 200 in the IP address allocation waiting mode in step S 701 receives a finish request of a timer operated to allocate the IP address of the access terminal in step S 718 , the access point 200 performs the deregistration process in steps S 719 and S 720 .

The above-described methods and apparatuses are not only realized by the exemplary embodiment of the present invention, but, on the contrary, are intended to be realized by a program for realizing functions corresponding to the configuration of the exemplary embodiment of the present invention or a recording medium for recording the program.

While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.