KR100695250B1 - Session Information Management Method in Wireless Internet System Using Keep-Alive Message - Google Patents

Abstract

The present invention relates to a session information management method using a keep-alive message management method in a portable internet system.

In order to realize this, the present invention includes the steps of: (a) transmitting a Keep-Alive Request message from a wireless base station to a mobile communication terminal in which a session is established with a wireless base station and long-term traffic is not transmitted or received; (b) checking whether a keep-alive response message, which is a response signal to the keep-alive request message, is received from the mobile communication terminal; And (c) erasing session information established with the mobile communication terminal when the Keep-Alive Response message from the mobile communication terminal has not been received for a predetermined response time or number of responses.

According to the present invention, the HPi system periodically checks session information by exchanging a KA-REQ message and a KA-RSP message for a session connection state between a mobile communication terminal and a wireless base station, and stops exchanging session information. By efficiently erasing session information, unnecessary session information can remain in the HPi system to prevent traffic or saturate the database.

Mobile Internet, HPi, Session, Keep-Alive, KA-REQ, KA-RSP, Wireless Base Station

Description

Session Information Management Method in Wireless Internet System Using Keep-Alive Message}

1 is a schematic view showing an HPi system according to a preferred embodiment of the present invention.

2A is a view showing a transmission format and structure of a Keep-Alive Request (KA-REQ) message according to an embodiment of the present invention;

2b is a view showing a transmission format and structure of a Keep-Alive Response (KA-RSP) message according to a preferred embodiment of the present invention;

3 is a flowchart illustrating a method of operating a keep-alive message according to an exemplary embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

100: mobile communication terminal 110: wireless base station

120: access control router 130: HA

140: AAA 150: IP network

160: Internet 210: Management Message Type Display

220: Transaction ID display unit 230: TLV Encoded Attributes display unit                 

240: Confirmation code display unit

The present invention relates to a session information management method using a keep-alive message management method in a portable internet system. More particularly, the present invention relates to a method for managing session information set with a wireless base station for data transmission through operation of a keep-alive message when using a high-speed portable Internet using a mobile communication terminal.

As computer, electronic, and communication technologies have made rapid progress, various wireless communication services using wireless networks have been provided. The most basic wireless communication service is a wireless voice call service that provides a voice call to a user of a mobile support station (MSS) wirelessly, which can provide a service regardless of time and place. In addition, while providing a text message service to complement the voice call service, a wireless Internet service has recently emerged to provide an Internet communication service to a user of a mobile communication terminal through a wireless communication network.

As a result of the development of mobile communication technology, a service provided by a code division multiple access (CDMA) mobile communication system transmits data such as circuit data and packet data as well as voice service. It is developing into a multimedia communication service.                         

In recent years, with the development of information and communication, IMT-2000 (International Mobile Telecommunication 2000), a third generation mobile communication system that has been standardized by ITU-R (for example, CDMA2000 1X, 3X, EV-DO, WCDMA (WideBand CDMA)) Etc.) are commercially available. IMT-2000 is CDMA 2000 1X, 3X, EV-DO, WCDMA (WideBand CDMA), etc .. It is a service that can provide wireless Internet at a transmission speed of up to 144 Kbps, much faster than the supportable data transfer rate of 14.4 Kbps or 56 Kbps. In particular, by using IMT-2000 service, it is possible to provide various multimedia services (AOD, VOD, etc.) at higher speed as well as improving existing voice and WAP service quality.

However, the existing mobile communication system has a high cost of using the wireless Internet because of the high cost of establishing a base station (BS), and because the screen size of the mobile communication terminal is small, there is a limitation on the available content. There is a limit to providing this. In addition, wireless local area network (WLAN) technology has limitations in providing public services due to problems such as radio wave interference and narrow coverage. Accordingly, a high-speed portable internet system (hereinafter referred to as 'HPi') has emerged, which guarantees portability and mobility and can use a high-speed wireless internet service at a low price.

The HPi system uses a 2.3 GHz frequency band, uses a time division duplex (TDD) as a duplex method, and orthogonal frequency division multiple access (OFDMA) as an access method. In addition, it provides mobility of 60 km / h per hour, and the downlink transmission rate is 24.8 Mbps, but the uplink transmission rate is 5.2 Mbps, which is an IP (Internet Protocol) based wireless data system having up and down asymmetric transmission characteristics.

In systems that support CDMA2000 1X, 3X, EV-DO, WCDMA, IS-95C and other wireless data providing services, including HPi systems, establish a session between the mobile communication terminal and the wireless base station and transmit data through the established session. I'm trying to. A mobile communication terminal in which a session is established is guaranteed mobility through continuous session information exchange with a wireless base station. When the traffic transmission between the mobile communication terminal and the wireless base station is interrupted for a predetermined time, the wireless base station erases session information of the mobile communication terminal to suppress resource acquisition and traffic generation. However, unlike the aforementioned various wireless data providing service systems, the session information erasing procedure is not defined in the HPi system.

Therefore, when traffic transmission between the mobile communication terminal and the wireless base station is interrupted for a long time in the HPi system, the session information of the mobile communication terminal in which the traffic transmission is interrupted is erased so that unnecessary session information remains in the HPi system for a long time to generate traffic. There is a need for a session information erasing procedure to prevent saturation of the database.

In order to solve the above problems, the present invention provides a method of operating a keep-alive message for managing session information established with a base station for data transmission when using a high-speed portable Internet using a mobile communication terminal in an HPi system. Has its purpose.

In order to achieve the above object, the present invention provides a method for managing session information between a wireless base station and a mobile communication terminal using Keep-Alive message operation in a portable Internet system, comprising: (a) establishing a session with a wireless base station in a wireless base station; Transmitting a Keep-Alive Request message to a mobile communication terminal to which traffic is not transmitted or received for a long time; (b) checking whether a keep-alive response message, which is a response signal to the keep-alive request message, is received from the mobile communication terminal; And (c) in step (b), erasing session information established with the mobile communication terminal when the Keep-Alive Response message from the mobile communication terminal has not been received for a predetermined response time or number of responses. do.

In addition, to achieve another object of the present invention, the present invention provides a Keep-Alive message structure for managing session information between a wireless base station and a mobile communication terminal in a portable Internet system, the Keep-Alive message is a Keep-Alive Request message, Or a Manage Message Type display unit for indicating that the message is a Keep-Alive Response message; Transaction ID display unit for displaying the sender of the Keep-Alive message; And a TLV Encoded Attributes display unit having an empty space for adding another parameter.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are designated as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

1 is a schematic view showing an HPi system according to a preferred embodiment of the present invention.

As shown in FIG. 1, the HPi system includes a mobile communication terminal 100 that is an MSS, a wireless base station (BS) 110 that is an access point (AP), and a packet access router that accommodates a plurality of base stations 110. An access control router (ACR) 120, a home agent (HA) 130, an authentication, authorization, accounting (AAA) 140, an IP network 150, the Internet 160, and the like.

Here, the mobile communication terminal 100 according to the preferred embodiment of the present invention refers to a mobile communication terminal using a high-speed wireless Internet service by accessing an HPi system, and has a low power RF / Intermediate Frequency (IF) module and a controller function. It performs the MAC (Media Access Control) frame variable control function, handoff function, authentication and encryption function according to service characteristics and propagation environment.

The wireless base station 110 according to the preferred embodiment of the present invention transmits data received from the ACR 120 as a AP of the HPi system to the mobile communication terminal 100 by wireless, low power RF / IF module and controller function, It has OFDMA / TDD packet scheduling, channel multiplexing function, MAC frame variable control function according to service characteristics and propagation environment, 50 Mbps high-speed traffic real-time control function, and handoff function.

The wireless base station 110 according to the preferred embodiment of the present invention exchanges a Keep-Alive message for managing session information with the mobile communication terminal 100. Here, the Keep-Alive message for managing session information is a Keep-Alive Request (KA-REQ, hereinafter referred to as KA-REQ) message and a Keep-Alive Response (KA-RSP, hereinafter referred to as KA-RSP). Message). In this case, the KA-REQ message is transmitted from the wireless base station 110 to the mobile communication terminal 100 in order to check whether a session setting for transmitting and receiving data between the mobile communication terminal 100 and the wireless base station 110 is possible. This message is sent at regular intervals. Here, although it is also possible to transmit the KA-REQ message from the mobile communication terminal 100 to the wireless base station 110, this description will only describe transmitting the KA-REQ message from the wireless base station 110 to the mobile communication terminal. Shall be.

The KA-RSP message is a message transmitted from the mobile communication terminal 100 receiving the KA-REQ message to the wireless base station 110 as a response signal. The structure of each message will be described in detail with reference to FIGS. 2A and 2B.

Here, the transmission period of the KA-REQ message can be set in advance by the system, and is set by two elements, Session Close Time and Number of Keep-Alive.

The Session Close Time value refers to a reference time for terminating a session and has a size of 2 bytes, that is, 16 bits. The default value is set to 2880 minutes, or 48 hours. If the Session Close Time value is 0, this means that the Keep-Alive feature is not used.                     

The Number of Keep-Alive value means the number of times the Keep-Alive message is checked. It has a size of 1 byte, that is, 8 Bits, and the default value is 3 times. If the previously mentioned Session Close Time value is 48 hours and the Number of Keep-Alive value is 3 times, this means that the Keep-Alive message is sent and received 3 times in 48 hours.

If there is no response through the KA-RSP message from the mobile communication terminal 100 for a predetermined response time or a predetermined response time for the KA-REQ message sent from the wireless base station 110, it is determined that session establishment is impossible. The wireless base station 110 terminates the session with the mobile communication terminal 100 and deletes the session information with the mobile communication terminal.

In the above description, a Session Close Time value, a Number of Keep-Alive value, a KA-RSP message response time and a response number for terminating a session (deleting session information) may be variously changed according to the setting in the service providing system. .

Meanwhile, the mobile communication terminal 100 and the base station 110 according to the preferred embodiment of the present invention have a 50 Mbps packet transmission modulation and demodulation function, a high speed packet channel coding function, a real time modem control function, and the like for data transmission.

ACR 120 according to a preferred embodiment of the present invention is an access control router that accommodates a plurality of base stations 110, the handoff control function between the base station 110, the handoff function between the ACR 120, packet routing function, the Internet It has a connection function and the like, and is connected to the IP network 150.

The HA 130 according to the preferred embodiment of the present invention performs routing for transmitting a packet transmitted from an external packet data service server such as the Internet 160, and the AAA 140 performs the mobile communication terminal 100. Charges the packet data used in the UE, and authenticates the connection from the mobile communication terminal 100.

The IP network 150 according to the preferred embodiment of the present invention connects the HA 130 and the AAA 140 and receives the packet data from an external packet data service such as the Internet 160 to the base station 110. send.

2A is a diagram illustrating a transmission format and a structure of a KA-REQ message according to a preferred embodiment of the present invention.

According to an embodiment of the present invention, the KA-REQ message transmitted from the wireless base station 110 to the mobile communication terminal 100 is defined as No. 61 type of Medium Access Control (MAC) Management, and a primary CID (Primary Management) in connection type. Connection Identifier).

Accordingly, the KA-REQ message transmission format having a form such as 2A transmits the phrase 'Management Message Type = 61', thereby indicating that this Keep-Alive message is a KA-REQ message. It also displays the 'Transaction ID', which is used to indicate the sender who sent the KA-REQ message. In addition, the KA-REQ message transmission format has a part indicated as 'TLV Encoded Attributes', and this part includes an extra space for adding another parameter that does not have any meaning in the KA-REQ message. to be.

The KA-REQ message transmitted in the format of 2A has the same structure as 2B. The management message type display unit 210 has a size of 8 bits and is displayed as '00111101' to display '61'. Transaction ID display unit 220 has a size of 16 Bits. The TLV Encoded Attributes (TLV) Encoded Attributes (TLV) display unit 230 is an extra space, and thus can be variously adjusted in size.

When the KA-REQ message having the format and structure is transmitted, the mobile communication terminal 100 receiving the KA-REQ message transmits the KA-RSP message as a response signal.

2B is a diagram illustrating a transmission format and a structure of a KA-RSP message according to a preferred embodiment of the present invention.

According to an embodiment of the present invention, the KA-RSP message transmitted from the mobile communication terminal 100 to the wireless base station 110 is defined as No. 62 type of Medium Access Control (MAC) Management, and main CID (Primary Management) in connection type. Connection Identifier).

Accordingly, the KA-RSP message transmission format having a form such as 2C transmits the phrase 'Management Message Type = 62', thereby indicating that the Keep-Alive message is a KA-RSP message. And, it includes a 'Transaction ID' portion to indicate the sender who sent the KA-RSP message. In addition, the KA-RSP message indicates a 'Confirmation Code', which is a part for indicating that the KA-REQ message has been received. The KA-RSP message transmission format also includes 'TLV Encoded Attributes', which is an extra space for adding other parameters.

The KA-RSP message transmitted in the 2C format has a 2D-like structure. The management message type display unit 210 displays '00111110' to display '62', and displays the message sender ID on the Transaction ID display unit 220 having a size of 16 bits. The Confirmation Code display unit 240 has a size of 8 Bits. The remaining portion is occupied by the TLV Encoded Attributes display unit 230.

The transmission format and structure of the KA-REQ message and the KA-RSP message described above with reference to FIGS. 2A and 2B are merely examples, and the transmission format and structure may be variously modified in the actual implementation of the present invention.

3 is a flowchart illustrating a method of operating a keep-alive message according to an exemplary embodiment of the present invention.

If a session is established between the mobile communication terminal 100 and the wireless base station 110 and no traffic is currently being transmitted (S310), the wireless base station 110 uses the Session Close Time value and the Number of Keep-Alive value. According to the set period, the mobile communication terminal 100 transmits a KA-REQ message for determining whether the session can be established (S320).

The mobile communication terminal 100 receiving the KA-REQ message generates a KA-RSP message as a response signal and transmits the KA-RSP message to the wireless base station 110 again. In this case, when the mobile communication terminal 100 is turned off or outside the reception area, the mobile communication terminal 100 does not receive the KA-REQ message and thus cannot generate the KA-RSP message (S330).

The wireless base station 110 checks whether the KA-RSP message is received from the mobile communication terminal 100, and maintains a session with the mobile communication terminal 100 when the KA-RSP message is received. Subsequently, the operation after step S320 for checking the session information with the mobile communication terminal 100 is repeatedly executed at a predetermined cycle (S340).

However, if the wireless base station 110 does not receive a response through the KA-RSP message from the mobile communication terminal 100 for a predetermined response time or response time, it is determined that it is impossible to maintain a session with the mobile communication terminal 100. In step S350, the session is terminated and the session information with the corresponding terminal is deleted. In this case, the response period and the number of responses may be set in various ways as necessary.

1 to 3, the wireless base station 110 transmits a KA-REQ message and generates a KA-RSP message in the mobile communication terminal 100 that receives the KA-REQ message. In the following description, the mobile communication terminal 100 generates and transmits a KA-REQ message, and the wireless base station 110 responds with a KA-RSP message. It is also possible to do

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, the HPi system periodically checks the session connection status between the mobile communication terminal and the wireless base station by sending and receiving a KA-REQ message and a KA-RSP message, and the corresponding mobile station has stopped traffic for a long time. The session information of the communication terminal can be efficiently erased, thereby preventing unnecessary session information from remaining in the HPi system for a long time to generate traffic or saturation of the database.

Claims (6)

A method of managing session information between a wireless base station and a mobile communication terminal using Keep-Alive message operation in a portable Internet system, (a) transmitting, by the wireless base station, a Keep-Alive Request message to the mobile communication terminal in which a session is established with the wireless base station and long-term traffic is not transmitted or received; (b) confirming whether to receive a Keep-Alive Response message, which is a response signal to the Keep-Alive Request message, from the mobile communication terminal; And (c) in the step (b), erasing session information established with the mobile communication terminal when the keep-alive response message from the mobile communication terminal has not been received for a predetermined response time or response number. Session information management method using a Keep-Alive message in a portable Internet system comprising a. The method of claim 1, wherein step (a) comprises: The wireless base station transmits a Keep-Alive message to the mobile communication terminal according to a period set by a Session Close Time value and a Number of Keep-Alive value. Session information management method using. The method of claim 1, wherein step (b) comprises: When the wireless base station receives the Keep-Alive Response message from the mobile communication terminal, the step (a) is repeated, the session information management method using a Keep-Alive message in a portable Internet system. The method of claim 1, A Manage Message Type display unit for indicating that the Keep-Alive message is the Keep-Alive Request message or the Keep-Alive Response message; Transaction ID display unit for displaying the sender of the Keep-Alive Request message or the Keep-Alive Response message; And TLV (Type, Length, Value) Encoded Attributes (TLV) display with empty space for adding other parameters Session information management method using a Keep-Alive message in a portable Internet system comprising a. The method of claim 4, wherein the Keep-Alive Response message, And a Confirmation Code display unit for confirming that the Keep-Alive Request message has been received. The method of claim 4, wherein the Keep-Alive message, A session information management method using a keep-alive message in a portable internet system, characterized by being classified as a primary CID (Primary Message Connection Identifier) in connection type.

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