KR20060081540A - Flow control method in reverse erasure state for data service assessment error minimization in wireless telecommunication system - Google Patents

Abstract

The present invention relates to a call control method considering backward degradation in order to minimize data service charging error in a wireless communication system. The present invention relates to an error in charging data caused by a mismatch of data transmission rates between a radio access network (RAN) and a wired network (CN). In the call control method considering the backward degradation during the degradation of the public network, the reference value for determining the reverse degradation state is set, and the data transmission stop (GRE XOFF) threshold is considered in consideration of the reverse degradation according to the data transmission speed of the public network. Setting a reference value and a threshold value; A deterioration state detection step of detecting a reverse deterioration state in a radio access network based on the 'reverse deterioration state determination reference value'; In the reverse degradation state, the RAN measures the amount of data accumulated in the 'data buffer in which the data transmitted from the packet data service node (PDSN) is accumulated', so that the measured data amount is 'the GRE XOFF threshold value considering the reverse degradation'. In case of abnormality, the data transmission stop step of stopping transmission of data by sending a data transmission stop (GRE XOFF) message to the PDSN by the RAN; And resuming data transmission by the RAN transmitting a data transmission resume (GRE XON) message to the PDSN upon resolving the reverse degradation state.

Charge Error, Call Control, GRE XOFF, GRE ON, Reverse Degradation

Description

Flow control method in reverse erasure state for data service assessment error minimization in wireless telecommunication system to minimize data service charging error in wireless communication system             

1 is an explanatory diagram showing a process of generating a data service charging error due to a data buffer overflow of a radio access network (RAN) according to the prior art;

2 is an explanatory diagram illustrating a process of generating a data service charging error due to call release in a state where data accumulated in a data buffer of a radio access network (RAN) exists according to the prior art;

3 is an exemplary configuration diagram of a wireless communication system to which the present invention is applied;

4 is a flowchart illustrating a call control concept between a radio access network (RAN) and a packet data service node (PDSN) according to the present invention;

5 is a flowchart illustrating a call control method without considering public network degradation (forward / reverse degradation) in order to minimize data service charging error according to the present invention;

6 is a flowchart illustrating another embodiment of a call control method considering backward degradation in order to minimize data service charging error according to the present invention.

* Explanation of symbols on the main parts of the drawing

10: mobile communication terminal (MS) 20: wireless access network (RAN)

21: base station (BTS) 22: base station controller (BSC)

23: packet controller (PCF) 30: packet data service node (PDSN)

40: authorization / certification / billing (AAA) server 50: home agent (HA)

The present invention relates to a call control method for minimizing data service charging error in a wireless communication system. More particularly, the present invention relates to data between a radio access network (RAN) and a data core network (DCN) which is a wired network. A call control method for minimizing an error in billing data caused by a mismatch in transmission speed, and a computer-readable recording medium having recorded thereon a program for realizing the method.

In particular, the present invention provides a call that considers backward degradation during degradation of a public network between a radio access network (RAN) and a packet data serving node (PDSN) of a data core network (DCN) that is a wired network. A control method and a computer-readable recording medium having recorded thereon a program for realizing the method.

Referring to Figure 3 will be described the process of generating a data service billing error in accordance with the prior art.

The wireless communication system includes a mobile station (MS) 10, a base station transceiver subsystem (BTS) 21, a base station controller (BSC) 22, and a packet controller (PCF). A function 23 is organically connected between a Radio Access Network (RAN) 20 and a Data Core Network (DCN), which is a wired network.

Here, the wired data core network (CN) includes a packet data serving node (PDSN) 30, an authorization / authentication / billing (AAA) server 40, and a home agent (HA: Home). Agent) 50 or the like.

Functions of the components of the wireless communication system will be described in more detail below.

Typically, data transmitted from the packet data service node (PDSN) 30 to the packet controller (PCF) 23 of the radio access network (RAN) 20 is transmitted from the radio access network (RAN) 20 to the mobile communication terminal (MS). Prior to transmission to the 10), it is preferentially stored in the base station controller (BSC) 22 of the radio access network (RAN) 20.

The reason is that the transmission speed of public network cannot be the same as that of wired network. That is, since the transmission rate of data transmitted from the radio access network (RAN) 20 to the mobile communication terminal (MS) 10 is different from the data transmission speed in the data core network (DCN), which is a wired network, the radio access network (RAN) The data is first stored before the data is transmitted from the mobile communication terminal (MS) 10 at 20.

In general, the wireless communication charging method may be divided into a circuit based charging method and a packet based charging method. The circuit-based billing method mainly calculates the fee by measuring time, and the packet-based billing method mainly calculates the fee by measuring the delivery volume of the packet. Of course, there is also a flat fee. Packet-based billing is a technology that is attracting much attention in recent years regarding the activation of wireless Internet service because it is suitable for connectionless services such as Internet service and low cost. Of these, the present invention relates to packet-based charging schemes.

The collection of charging data in the packet data call supported by the wireless communication system is performed in the packet data service node (PDSN) 30, which is carried out by the mobile communication terminal (MS) through the wireless access network (RAN) 20. The charge is made by transmitting the number of Data Packets transmitted and received to and from the 10 to the authorization / authentication / billing (AAA) server 40.

However, the accuracy of the number of data packets transmitted and received with the mobile communication terminal (MS) 10 through the radio access network (RAN) 20 may vary greatly depending on the data transmission speed and the quality of the public network.

Therefore, as described above, since the transmission speed of the public network cannot be the same as the transmission speed of the wired network, that is, the transmission speed and the wired network of data transmitted from the radio access network (RAN) 20 to the mobile communication terminal (MS) 10. Since the data transmission speed in the DCN is different, the data is preferentially stored in the data buffer before the data is transmitted from the radio access network (RAN) 20 to the mobile communication terminal (MS) 10. .

By the way, the number of data packets transmitted from the packet data service node (PDSN) 30, which is the basis of charging, to the radio access network (RAN) 20, actually moves in the radio access network (RAN) 20. It may be much larger than the number of packet data transmitted to the communication terminal (MS) 10.

This problem is caused by a large amount of data from the packet data service node (PDSN) 30 exceeding the data buffer size set in the radio access network (RAN) 20 as shown in FIG. 1. May occur when received. That is, when overflow occurs because the data storage space (data buffer) of the radio access network (RAN) 20 is insufficient, a charging error occurs as much as the amount of discarded data (101).

In addition, the problem may occur when there is data accumulated in the radio access network (RAN) 20 at the time when the data call is released 201 as shown in FIG. In other words, when there is data accumulated in the radio access network (RAN) 20 at the time when the data call is released, a charging error occurs as much as the accumulated data amount (remaining data amount) (202). In other words, if the call is released in the state where data accumulated in the radio access network (RAN) 20 exists, a charging error occurs as much as the amount of residual data accumulated in the data storage space (data buffer).

Therefore, in recent years when wireless data services are becoming more common, there is an urgent need for a method of minimizing the above billing error. In particular, there is an urgent need for a method of minimizing the charging error due to the data buffer overflow of the radio access network (RAN).

The present invention has been proposed in order to meet the above-mentioned requirements. In order to minimize the error of billing data caused by the inconsistency of the data transmission rate between the radio access network (RAN) and the wired network (CN), the reverse degradation during the degradation of the public network is considered. An object of the present invention is to provide a call control method and a computer-readable recording medium having recorded thereon a program for realizing the method.

Other objects and advantages of the present invention can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. In addition, it will be readily appreciated that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the claims.

In order to achieve the above object, the present invention provides a call control method for reducing a data service charging error in a wireless communication system, comprising setting a reference value for determining a reverse degradation state and considering backward degradation according to a data transmission speed of a public network. A reference value and threshold setting step of setting a GRE XOFF threshold; A deterioration state detection step of detecting a reverse deterioration state in a radio access network (RAN) based on the 'reverse deterioration state determination reference value'; In the reverse degradation state, the RAN measures the amount of data accumulated in the 'data buffer in which the data transmitted from the packet data service node (PDSN) is accumulated', so that the measured data amount is 'the GRE XOFF threshold value considering the reverse degradation'. In case of abnormality, the data transmission stop step of stopping transmission of data by sending a data transmission stop (GRE XOFF) message to the PDSN by the RAN; And resuming data transmission by the RAN transmitting a data transmission resume (GRE XON) message to the PDSN upon resolving the reverse degradation state.

Meanwhile, the present invention sets a reference value for determining a reverse degradation state in a wireless communication system having a processor for call control considering backward degradation in order to minimize data service charging error, and reverse degradation according to the data transmission speed of a public network. A reference value and threshold setting function for setting a data transmission stop (GRE XOFF) threshold in consideration of the value of the threshold; A degradation state detection function for detecting a reverse degradation state in a radio access network based on the 'reverse degradation state determination reference value'; In the reverse degradation state, the RAN measures the amount of data accumulated in the 'data buffer in which the data transmitted from the packet data service node (PDSN) is accumulated', so that the measured data amount is 'the GRE XOFF threshold value considering the reverse degradation'. In case of abnormality, the data transmission stop function causes the RAN to send a data transmission stop (GRE XOFF) message to the PDSN to stop data transmission; And a computer-readable recording recording a program for realizing a data transmission resume function for resuming data transmission by transmitting a data transmission resume (GRE XON) message to the PDSN upon cancellation of the reverse degradation state. Provide the medium.

In the present invention, to minimize the charging error, it is intended to add a call control function between the radio access network (RAN) and the packet data service node (PDSN).

According to the present invention, when adding call control (Flow Control) between the radio access network (RAN) and the packet data service node (PDSN), by adjusting the amount of data accumulated in the radio access network (RAN) in accordance with the transmission speed of the public network If the data storage space (data buffer) of the radio access network (RAN) is insufficient, or the data (residual data) remaining in the radio access network (RAN) when the data call is released can be minimized.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, whereby those skilled in the art may easily implement the technical idea of the present invention. There will be. In addition, in describing the present invention, when it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is an exemplary configuration diagram of a wireless communication system to which the present invention is applied.

Radio access network (RAN) 20 is composed of a packet controller (PCF) 23, a base station controller (BSC) 22, a base station (BTS) 21, and visitor location register (VLR) (drawings) Mobility management and authentication of the mobile communication terminal (MS) 10 is provided through a home location register (HLR) (not shown).

Here, the base station controller (BSC) 22 controls and manages one or more base stations (BTS) 21, traffic and signaling methods associated with call processing, mobility management, and mobile communication terminal (MS) 10 management, etc. Do this.

In addition, the packet controller (PCF) 23 may exist inside the base station controller (BSC) 22, may be implemented as a separate system to the outside, and the mobile communication terminal delivered from the radio access network (RAN) 20 The data of the (MS) 10 are connected to a packet data service node (PDSN) 30.

The packet data service node (PDSN) 30 performs a foreign agent (FA) function. The packet data service node (PDSN) 30 delivers incoming and outgoing packets for packet data of the mobile communication terminal (MS) 10 to an appropriate path. (MS) performs the termination role of setting and managing the connection layer protocol of the (10).

Authorization / authentication / billing (AAA) server 40 provides Internet protocol functionality to support authentication, authorization, and billing functions.

The home agent (HA) 50 manages the IP address of the external agent (FA) as a table of location information on the mobile IP, and transmits transmission data for the subscriber through tunnel and encryption as necessary. .

When the basic authentication of the data call is completed, the radio access network (RAN) 20 establishes a virtual connection for the packet data service node (PDSN) 30 and the Generic Routing Encapsulation (GRE) protocol.

The packet data service node (PDSN) 30 establishes a point-to-point protocol (PPP) connection with a mobile communication terminal (MS) 10 and authorizes, authenticates, and charges (AAA) servers. Through 40, the subscriber authentication and billing information is transmitted.

In providing the mobile IP service, the packet data service node (PDSN) 30 performs an external agent (FA) function, and the home agent (HA) 50 existing in the home network of the mobile communication terminal IP address provides a mobile IP. It performs functions such as location information management and tunnel setting for

In particular, the packet controller (PCF) 23 is an interworking system of a radio access network (RAN) 20 for interworking with a packet network, and the packet data service node (PDSN) 30 is a radio access network (RAN) ( It functions as an access node for connecting the data subscriber connected through the network 20 to the packet network, and the radio access network (RAN) 20 and the packet network are completely separated from each other.

Accordingly, the packet controller (PCF) 23 may exist inside the base station controller (BSC) 22 system or may be implemented as a separate system. However, the packet controller (PCF) 23 may be implemented as an independent system mainly for providing effective mobility in the mobile network. have.

Looking at the function of the packet controller (PCF) 23 in more detail, the data of the mobile communication terminal (MS) 10 from the radio access network (RAN) 20 to the packet data service node (PDSN) 30 In order to make a connection, a connection method between a radio access network (RAN) and a packet data network (PDN) called an "RP interface" is used, and a subscriber-specific virtual link connection for data transmission in an RP connection Tunneling of user data through GRE protocol encapsulation and decapsulation. In addition, the temporary storage for transmitting the link layer packets to be transmitted to the mobile communication terminal (MS) 10 received from the packet data service node (PDSN) 30 over the air interface (Air Interface) ( Buffer) and packet segmentation function.

Packet data service node (PDSN) 30 performs PPP / GRE protocol processing to process packets received from packet controller (PCF) 23.

By the way, in packet charging, the most important devices are the packet data service node (PDSN) 30 and the authorization / authentication / billing (AAA) server 40. The functions of these two devices 30 and 40 and the contents of the messages sent and received are defined by the standard. The functions and messages related to charging in the two devices 30 and 40 are as follows.

The packet data service node 30 is a device through which a packet requesting service authentication and packet data for an actual authenticated user are passed. The packet data service node 30 accepts an authentication / authorization message as it is. To pass on. The amount of packets transmitted for the actual service is counted during the session, and the result is notified to the authorization / authentication / billing (AAA) server 40.

An authorization / authentication / billing (AAA) server 40 is a device for authentication, authorization acceptance, packet count measurement, etc. for a service, and processes an authentication or authorization acceptance message sent by a packet data service node (PDSN) 30. It is responsible for classifying the packet usage for the user. In particular, the authorization / authentication / billing (AAA) server 40 may obtain necessary information by using parameters of an account request message and a bearer data message.

Here, the accounting request message has a terminal address (IP) and a network access identifier (NAI) information about the packet. Using this information, the mapping relationship between IP and NAI is defined, and billing-related information that is found through bearer data message is classified by NAI.

In addition, a bearer data message has a source IP, a destination IP, a direction flag, a number of packets transmitted, a source port, and a destination port information. In this case, the corresponding port is used to distinguish a service in a content provider CP.

However, as described above, since the transmission rate of data transmitted from the radio access network (RAN) 20 to the mobile communication terminal (MS) 10 is different from the data transmission rate in the data core network (DCN), which is a wired network, Prior to transmitting data from the radio access network (RAN) 20 to the mobile communication terminal (MS) 10, data is preferentially stored in a data buffer. In this process, the data storage space of the radio access network (RAN) 20 is stored. If the overflow occurs due to lack of (data buffer), charging error occurs as much as the amount of discarded data, or if the call is released in the presence of accumulated data in the radio access network (RAN) 20, the data storage space (data buffer) The charging error occurs as much as the amount of residual data accumulated in the).

In order to minimize such a charging error, a call control function between the radio access network (RAN) 20 and the packet data service node (PDSN) 30 is required. In the present invention, the call control function is adapted to the transmission speed of the public network. When the data storage space (data buffer) of the radio access network (RAN) 20 is insufficient (see FIG. 1) or when the data call is released by adjusting the amount of data accumulated in the radio access network (RAN) 20, The charging error that occurs when there is data remaining in the access network (RAN) 20 (see FIG. 2) can be minimized.

Looking at this in detail.

When the wireless connection is established and the session is activated and charging is started, data is transmitted from the packet data service node (PDSN) 30 to the packet controller (PCF) 23 of the radio access network (RAN) 20.

At this time, the radio access network (RAN) 20 transmits a "GRE XOFF" message to the packet data service node (PDSN) 30 as shown in FIG. 4 (401), and the packet data service node (PDSN) 30 May stop the transmission of data to be transmitted to the radio access network (RAN) 20.

In addition, the radio access network (RAN) 20 transmits a "GRE XON" message to the packet data service node (PDSN) 30 as shown in FIG. 4 (402), whereby the packet data service node (PDSN) Data transmission to the access network (RAN) 20 may be resumed.

In the above description, "GRE OXFF" or "GRE XON" means XOFF or a GRE packet which is a bearer data interface protocol between a radio access network (RAN) 20 and a packet data service node (PDSN). Contains XON information.

Therefore, the core of the flow control between the radio access network (RAN) 20 and the packet data service node (PDSN) 30 is "GRE XOFF (stop data transmission) performed in the radio access network (RAN) 20. It can be seen that it is determined depending on the transmission time of "or" GRE XON (resume data transmission) ".

Based on this, the call control method according to the present invention is as follows.

First, referring to FIG. 5, a call control process without considering the deterioration of the public network (forward / reverse deterioration) will be described. In FIG. 6, a call control process considering the deterioration of the public network will be described.

Referring to FIG. 5, the transmission time of "GRE XOFF (data transmission stop)" or "GRE XON (resume data transmission)" is determined by the amount of data accumulated in the radio access network (RAN) 20 regardless of the degradation of the public network. The process of doing this is as follows.

When the wireless connection is established and the session is activated and charging is started, data is transmitted from the packet data service node (PDSN) 30 to the packet controller (PCF) 23 of the radio access network (RAN) 20.

In this case, the radio access network (RAN) 20 measures the amount of data accumulated in the data buffer of the radio access network (RAN) 20, and when the accumulated data amount is equal to or greater than a threshold set by the operator (501) (501). , Transmits a “GRE XOFF (Stop Data Transfer)” message to the packet data service node (PDSN) 30 (502).

In addition, when the amount of data accumulated in the radio access network (RAN) 20 is less than or equal to the GRE XON Threshold set by the operator (503), a "GRE XON (resume data transmission)" message is received. The packet is transmitted to the packet data service node (PDSN) 30 (504).

Here, the "GRE XOFF Threshold" and the "GRE XON Threshold" are set differently according to the data transmission speed of the public network. For example, for 8Kbps data service, set "GRE XOFF Threshold" to 10,000 bytes and "GRE XON Threshold" to 8,000 bytes, but for 64kbps data service, "GRE XOFF Threshold" is 40,000 bytes and "GRE XON Threshold" "Is set to 24,000 bytes.

On the other hand, referring to Figure 6, look at the process of determining the transmission time of "GRE XOFF (data transmission stop)" or "GRE XON (resume data transmission)" in consideration of the reverse degradation of the public network as follows.

When the wireless connection is established and the session is activated and charging is started, the data is transmitted from the packet data service node (PDSN) 30 to the packet controller (PCF) 23 of the radio access network (RAN) 20.

At this time, the radio access network (RAN) 20 monitors forward and reverse degradation in real time. If a reverse degradation occurs (601), the amount of data accumulated in the data buffer of the radio access network (RAN) 20 is measured. If the accumulated data amount is equal to or greater than the GRE XOFF Threshold in Reverse Erasure State set by the operator (602), a "GRE XOFF" message is sent to the packet data service node (PDSN) 30. (603).

In addition, in the state in which the radio access network (RAN) 20 transmits a "GRE XOFF" message due to backward degradation (603), when it is determined that backward degradation has been eliminated (604), a "GRE XON (resume data transmission resume)" message is received. 605 is transmitted to the packet data service node (PDSN) 30 (605).

Here, the "GRE XOFF threshold considering the reverse degradation" is set differently according to the data transmission speed of the public network. For example, for 8 Kbps data service, "GRE XOFF Threshold in Reverse Erasure State" is set to 7,000 bytes, but for 64kbps data service, "GRE XOFF Threshold in Reverse Erasure State" is set to 28,000 bytes.

In addition, the reference value for determining the reverse degradation state in the radio access network (RAN) 20 can be arbitrarily set by the operator. For example, when 50 reverse degradation frames are continuously received, it is determined as a reverse degradation state.

As described above, the method of the present invention may be implemented as a program and stored in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) in a computer-readable form. Since this process can be easily implemented by those skilled in the art will not be described in more detail.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

 The present invention as described above, can minimize the charging error due to the difference between the data transmission speed of the public network and the data transmission speed of the wired network, in particular to minimize the charging error due to the data buffer overflow (Overflow) of the radio access network (RAN) It can be effective.

In particular, the present invention has the effect of minimizing the charging error due to the reverse degradation of the public network.

Claims (2)

A call control method for reducing data service charging error in a wireless communication system, A reference value and threshold setting step of setting a reference value for determining a reverse degradation state and setting a data transmission stop (GRE XOFF) threshold in consideration of reverse degradation according to a data transmission speed of a public network; A deterioration state detection step of detecting a reverse deterioration state in a radio access network based on the 'reverse deterioration state determination reference value'; In the reverse degradation state, the RAN measures the amount of data accumulated in the 'data buffer in which the data transmitted from the packet data service node (PDSN) is accumulated', so that the measured data amount is 'the GRE XOFF threshold value considering the reverse degradation'. In case of abnormality, the data transmission stop step of stopping transmission of data by sending a data transmission stop (GRE XOFF) message to the PDSN by the RAN; And And resuming data transmission in the wireless communication system, wherein the RAN sends a data transmission resume (GRE XON) message to the PDSN upon resolving the reverse degradation state. Call control method with backward degradation to minimize errors. In a wireless communication system having a processor for call control considering backward degradation to minimize data service charging error, A reference value and threshold setting function for setting a reference value for determining a reverse degradation state and setting a data transmission stop (GRE XOFF) threshold in consideration of reverse degradation according to a data transmission speed of a public network; A degradation state detection function for detecting a reverse degradation state in a radio access network based on the 'reverse degradation state determination reference value'; In the reverse degradation state, the RAN measures the amount of data accumulated in the 'data buffer in which the data transmitted from the packet data service node (PDSN) is accumulated', so that the measured data amount is 'the GRE XOFF threshold value considering the reverse degradation'. In case of abnormality, the data transmission stop function causes the RAN to send a data transmission stop (GRE XOFF) message to the PDSN to stop data transmission; And When the reverse degradation state is resolved, the RAN sends a data transmission resume (GRE XON) message to the PDSN, and a computer readable recording medium having recorded thereon a program for realizing a data transmission resume function to resume transmission of data. .

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