Cellular asynchronous transfer mode packet network and method for transmitting packet data

Asynchronous transmission method mobile communication packet network and packet data transmission method {ATM Packet Network and Method for Transmitting Packet}

1 is a block diagram of a mobile communication network using a conventional mobile switching center in an asynchronous transmission mode;

FIG. 2 is a signal protocol stack of a mobile communication network using a mobile switching center in an asynchronous transmission mode for establishing a packet call of a mobile terminal according to FIG. 1; FIG.

FIG. 3 is a data protocol stack of a mobile communication network using a mobile switching center in an asynchronous transmission mode for packet call forwarding of a mobile terminal according to FIG. 1; FIG.

4 is a block diagram of a cellular ATM packet network according to the present invention;

FIG. 5 is a packet data communication protocol stack by multiplexing packet data between a mobile station and a packet data node according to FIG. 4;

FIG. 6 is a packet data communication protocol stack by multiplexing packet data between the mobile station and another mobile station according to FIG. 4;

7 is a configuration diagram of an asynchronous transmission mode adaptation layer (ATM Adaptation Layer: AAL) shown in FIGS. 5 to 6;

8 to 9 are the configuration diagrams of the common service layer-protocol data unit payload shown in FIG.

10A to 10B are block diagrams of a control block of a specific service convergence layer shown in FIG. 8 and each block of PPP data.

FIG. 11 is a view showing types and request directions of control messages shown in FIG. 10;

*Explanation of symbols for main parts of the drawing*

101,103: mobile terminal 102: data terminal

111-114: base station 121-123: wireless network controller

131 : packet call controller 132 : mobile packet router

141 : Home Location Register 151-153 : Packet Data Node

161 : PSTN/ISDN 171 : Internet

<background-art><p> The present invention relates to a packet network and packet data transmission method, and in particular, to a communication environment in which subscribers continuously increase more than the capacity of a designed mobile communication system, an asynchronous transfer mode (hereinafter referred to as ATM) type switch is used. The present invention relates to a mobile communication packet network and packet data transmission method using an improved asynchronous transmission mode in a next-generation mobile communication system.</p><p>In the communication field, research is being conducted to introduce an ATM switch to a cellular/PCS mobile communication system that is currently commercially available. As an example, an ATM switch for transferring data from a cellular mobile terminal to a receiving side as shown in FIG. The mobile communication network used can be presented.</p><p>In FIG. 1 , user data transmitted from a specific mobile terminal 11 is transmitted to a radio network controller (RNC) 31 through a corresponding base station 21 . Then, the wireless network controller 31 transmits to the destination wireless network controller or the destination packet data node (PDN) 61 through the path determined by the Mobile Switching Center (MSC) 41 . do.</p><p>At this time, the signaling method between the wireless network controller 31 and the mobile switching center 41 for selecting and determining the data path of the mobile terminal 11 and the signaling method between the mobile switching center 41 and the packet data node 61 are ATM switches. As shown in FIG. 2 when using . That is, through the Signaling ATM Adaptation Layer (SAAL) provided in the wireless network controller 31, the mobile switching center 41, and the packet data node 61, respectively, according to the call setup signal method of the ATM switch, each mobile terminal One virtual circuit is assigned to each call so that user data is transmitted. </p><p>However, in the prior art, when the wireless network controller and the packet data node operate as nodes of a communication network using an ATM switch, the path of incoming data to be transmitted from the wireless network controller or packet data node is moved in the ATM method. It must be done through a virtual circuit of the Circuit Switched method through the switchboard. Therefore, the wireless network controller or packet data node must allocate a virtual line while the mobile terminal is connecting a data or voice call. However, virtual circuits of ATM-type mobile switching centers have limitations for each unit physical connection port. Also, additional time is required for signaling processing for setting up a virtual line. That is, when the calling mobile terminal is receiving packet data service by setting a packet route to the called mobile terminal or the host of the Internet network, the wireless network controller, the mobile switching center, and the packet data node allocate a virtual circuit for the corresponding packet route. do. The virtual line allocated in this way maintains an active state when data is transmitted, and transitions to a dormant state when not used for a certain period of time. Then, if the virtual line is used within a predetermined time, it transitions to the active state again, whereas if the virtual line is not used within a predetermined time, the virtual line is released. Accordingly, if there are many mobile terminals maintaining data paths in a dormant state in a time period with a high call volume or in a specific region, the number of virtual lines for many packet services may eventually be insufficient.</p><p>At this time, in order to prevent a virtual channel shortage, if the dormant virtual line is released when no data is transmitted for a certain period of time, when the corresponding mobile terminal wants to transmit a packet again, the released packet data path is restarted from the beginning. have to be set </p><p>As a result, the mobile communication network shown in FIG. 1 has a limit in the number of virtual lines that can be allocated when the call volume increases above a threshold, making it difficult to effectively set up a packet data service and easily solve the shortage of virtual lines. There was a problem.</p></background-art><tech><p>An object of the present invention has been devised in view of the problems of the prior art mentioned above, and transmits or transmits wireless packet data of a mobile terminal terminating in a wireless network controller to a wired packet network matching node or another wireless network controller. When an ATM switch is used for reverse transmission, a single virtual line is established between the packet network matching node and the wireless network controller, and cellular ATM packets are transmitted by multiplexing/demultiplexing multiple mobile terminals or packet sessions on the set virtual line. To provide a network and packet data transmission method. </p><p>According to one aspect of the present invention to achieve the above object, the cellular ATM packet network separates packet data and line data service paths when matching with the core network using a channel assignment function according to service options of a plurality of mobile stations. It is connected to multiple wireless network controllers that provide functions and multiple wireless network controllers in its own cell or sector, supports voice communication exchange functions and location registration and mobility of mobile stations, A packet call controller that manages packet access node information; an ATM switch type mobile packet router that routes outgoing packet data transmitted from each radio network controller or incoming incoming packet data to a set transmission path; It consists of a plurality of Packet Data Nodes (PDNs) that route outgoing packet data provided by a router or incoming incoming packet data according to an identifier.</p><p>According to another feature of the present invention for achieving the above other object, a packet transmission method in an ATM packet network includes at least one wireless network controller, In a cellular ATM packet network having a packet call controller, a packet data node, and a mobile packet router, respectively, establishing a virtual circuit between the radio network controller and another radio network controller or between the radio network controller and the packet data node, respectively; , when a packet path between the wireless network controller and another wireless network controller or between the wireless network controller and a packet data node is to be connected, a packet call to an individual terminal is placed on a virtual line connecting the corresponding wireless network controller and the packet data node Alternatively, multiplexing/demultiplexing individual data blocks for a packet session and performing packet routing on the multiplexed/demultiplexed data blocks.</p><p>According to the features of the present invention as described above, without allocating a virtual line for setting a packet path for each packet call or packet session of each mobile terminal, all wireless network controllers and wireless networks to which packets of mobile terminals are terminated When one virtual line is set between controllers or between all wireless network controllers and all packet data nodes and a packet path is assigned through the set virtual line, each movement is made to the virtual line connecting the corresponding wireless network controller or packet data node. By multiplexing/demultiplexing a packet call or packet session to a terminal, almost unlimited packet paths can be allocated to one virtual line, and the signaling procedure for setting the packet path of each mobile terminal is not executed. There is this.</p></tech>

<p>Hereinafter, the configuration and operation according to a preferred embodiment of the present invention are shown in the accompanying drawings. Refer to and explain.</p><p>4 is a block diagram of an asynchronous transmission mode packet network according to the present invention. Referring to FIG. 4, the ATM packet network according to the present invention includes a mobile terminal 101 providing a function of wireless connection with a base station or a user data terminal 102 providing a data communication function by being connected to the mobile terminal 103; , a plurality of base stations 111 to 114 providing a function of connecting a radio channel with each of the mobile terminals 101 and 103, and a plurality of base stations in its own cell or sector, and the service of the mobile terminals 101 and 103 A plurality of wireless network controllers 121-123 that provide a function of separating packet data and circuit data service paths when matching with the core network using an optional channel assignment function, and a plurality of wireless networks in its own cell or sector It is connected to the network controller and supports voice communication exchange function and location registration and mobility of mobile terminals 101 and 103, and provides location information of mobile terminals in packet service and packet access nodes (that is, A packet call controller 131 that manages information of the wireless network controller and packet data node), and a visitor location register that is connected to the packet call controller 131 and manages the mobility of each mobile terminal 101 and 103 (Home Location Register): HLR) 141, ATM switch type mobile packet router 132 for routing outgoing packet data or incoming incoming packet data transmitted from each wireless network controller 121-123 to a set transmission path, and moving packets It consists of a plurality of Packet Data Nodes (PDNs) 151-153 that route outgoing packet data provided by the router 132 or incoming incoming packet data according to an identifier. </p><p>Here, a communication network 161 comprising a public switched telephone network (PSTN)/integrated services digital network (ISDN) is connected to the packet call controller 131, and each packet data node 151-153 ) is connected to the Internet 171, respectively. In addition, the packet call controller 131 includes a mobile switching center (MSC)/visitor location register (VLR) that supports voice communication switching functions and location registration and mobility of terminals, and the location of each mobile terminal. It consists of a Location Management Function (LMF) that manages information and packet access node information.</p><p>In the cellular ATM packet network configured as described above, one virtual channel is allocated for every individual packet session in the same way as in the conventional method of allocating a virtual channel to a packet call or packet session of a specific mobile terminal 101 for a packet data service. When providing a packet path by allocating a channel, between each node of the ATM switch-type mobile packet router 132 (eg, using B-ISDN signaling specified in the International Telecommunication Union's standard document (Q.2931)) For example, when packet communication is performed between the mobile terminal 101 in the wireless network controller 121 area and the data terminal 102 in the wireless network controller 122 area, the wireless network controller 121 and the mobile packet router 132 ) and a mobile packet router 132 and a wireless network controller 122, When performing Internet packet communication through the mobile terminal 101 of the wireless network controller 121 and the specific packet data node 151, the wireless network controller 121, the mobile packet router 132, and the mobile packet router 132 It takes a considerable amount of time to set up a virtual channel between the packet data node 151 and the packet data node 151 .</p><p>In addition, as a method to improve this problem, if the mobile station's packet service is not in an active state and the transition to the dormant state is allowed to maintain the corresponding virtual channel even without data transmission, eventually the wireless connected through the mobile packet router The virtual channel between the network controller and the wireless network controller or the virtual channel between the wireless network controller and the packet data node is easily exhausted in a poor communication environment where the call volume abruptly exceeds the set threshold.</p><p>Therefore, in the present invention, in order to improve this, a fixed virtual channel (PVC) method or a switched virtual circuit between all wireless network controllers and wireless network controllers or between all wireless network controllers and all packet data nodes :SVC) method to set up a virtual channel, and if a packet path is to be allocated between a wireless network controller and a wireless network controller or between a wireless network controller and a packet data node, connect the corresponding wireless network controller or packet data node By multiplexing/demultiplexing each mobile terminal packet call or packet session to a virtual channel, sufficient packet paths can be allocated to one virtual channel. As described above, the present invention is an ATM adaptation of a Service Specific Convergence Sub-layer (SSCS) protocol having a function of multiplexing and demultiplexing packet session data of a mobile station suitable for a packet service based on a cellular mobile telephony network. It is possible by applying to the layer (Adaptation Layer) (hereinafter referred to as AAL). </p><p>ATM Adaptation Layer (AAL) is a function provided to provide an ATM Virtual Circuit between ATM end nodes or mobile terminals connected in a network equipped with an ATM switch. Such an ATM adaptation layer (AAL) is divided into five types (AAL1, AAL2, AAL3, AAL4, AAL5) according to the characteristics of data traffic to be delivered. In the present invention, signaling AAL (Signaling AAL) for setting up a virtual channel: Hereinafter, SAAL) is defined based on AAL5. In addition, each AAL is individually divided into a Common Part Convergence Sub-layer (CPCS) and a Service Specific Convergence Sub-layer (SSCS) of the corresponding layer. Here, SSCS is a function that can easily respond to various application environments, and it varies depending on the application field of a communication network equipped with an ATM switch.</p><p>In the present invention, SSCS that multiplexes/demultiplexes a packet call or packet session of each mobile terminal as shown in Figs. It is located in the AAL of cellular ATM packet network, and is a virtual channel assigned by the fixed virtual channel (PVC) method of the cellular ATM packet network or the ATM circuit-switched virtual channel (SVC) method of the ATM end node and the mobile packet router. It performs the function of multiplexing/demultiplexing of all packet session data transmitted, the change control function of the wireless network controller node according to the movement of each mobile station, the registration control function to the packet data node, and the cellular packet flow control function. . </p><p>In the present invention, the data block of AAL5 is transmitted between the wireless network controller and the wireless network controller of the cellular packet ATM network shown in FIG. 4 or through a virtual channel established between the wireless network controller and the packet data node, respectively. In this virtual channel, a packet call or packet session for a specific mobile station is multiplexed/demultiplexed and transmitted.</p><p>7 is a block diagram of a protocol data unit (PDU) of a CPCS of an asynchronous transmission mode adaptation layer (ATM Adaptation Layer 5: AAL5). A common service layer-protocol data unit payload field (CPCS-payload field) 200 that carries user information of up to 2^16 -1 bytes, and a common service layer-protocol data unit payload field 200 ), a pad field (PAD field) 210 that adjusts the size of the data block in a multiple of 48-byte ATM cell unit in the lower ATM segmentation and re-assembly (SAR sub-layer), and a common service layer A field for transparently transmitting information between users (User-to-User indication; CPCS-UU) 220 and a field used to make the total number of bits of the CPCS-PDU trailer to 64 bits (Common) Part Indicator ; CPI) 230, a Length field 240 indicating the size of the payload 200, and a field 250 indicating a CRC (Cyclic Redundancy Check) value of the entire CPCS-PDU data block except for its own field ) is composed of </p><p>In the present invention, the data block of the CPCS-PDU payload 200 of FIG. 7 may be defined as the SSCS-PDU block shown in FIGS. 8 to 9 . 8 is defined as a type A SSCS-PDU block, a source identifier (Source ID) 201 for identifying a multiplexing source of a virtual channel, and a destination identifier (Destination ID) 202 for identifying a demultiplexing destination; , indicates the service type of the packet call of the source terminal, and has the same service option as the Service Option (SO) field 203 used by the cellular packet ATM network for terminal access in the wireless section and has an independent packet session identifier. A packet session identifier (PSID) field 205 for distinguishing cases and a payload packet identifier (PPID) 205 used to distinguish an upper layer protocol identifier delivered as an SSCS-PDU payload 200 are included. do.</p><p>Here, the destination identifier (Destination ID) 202 is the terminal identifier (15 octets), the node identifier (16 octets) of the packet data node allocated by the cellular packet ATM network, or the default identifier (1 octet). is divided into Such classification is determined as follows by the value of the bit of the first octet of the field. That is, in the case of OxDD, it means a virtual channel connection packet data node as 1 octet default. In the case of 0xDF, it is 16 octets, and the identifier of the virtual channel connection packet data node is specified in the destination identifier field 202 . If it is not 0xDD or 0xDF, it is an identifier of the destination mobile terminal of 15 octets and is located in the virtual channel connection wireless network controller area.</p><p>9 is defined as a B-type SSCS-PDU block in which a field 206a for classifying the contents of the payload is added to 1 byte of the information field in FIG. 7, and the SSCS-PDU payload 200 in the configuration shown in FIG. 8 A C/D field 206a for discriminating whether the contents of is user data of a higher layer or SSCS control of both ends is added. Here, when the C/D field 206a is control data, the type of control data may be distinguished.</p><p>When the SSCS-PDU data block of AAL5 shown in FIGS. 8 to 9 is defined, between the radio network controller and the radio network controller by the source identifiers 201 and 201a and the destination identifiers 202 and 202a. Alternatively, individual packet data for multiple terminals can be multiplexed/demultiplexed on one virtual channel between the wireless network controller and the packet data node, and service option (SO) fields 203 and 203a and packet session identifiers ( PSID) fields 204 and 204a allow multiplexing/demultiplexing of individual mobile packet data for each service option and for each packet session identifier. In addition, the payload packet identifier (PPID) fields 205 and 205a allow the receiver to effectively identify the protocol of the upper layer delivered as the payload, and from the information in the C/D field 206a It can be easily determined whether the data of the payload is user data or SSCS control data.</p><p>Accordingly, when a cellular packet ATM network as shown in FIG. 4 is configured, 1) when a mobile station in the wireless network controller area transmits packet data having a specific service option and a packet session identifier to a specific terminal, the calling party wireless network controller /Packet controller (RNC/PCF) receives the node identifier of the destination radio network controller where the destination terminal is located from the packet call controller and checks the virtual channel identifier with the corresponding destination radio network controller, and SSCS uses the packet controller (PCF) ), creates an SSCS-PDU header by receiving the service option, packet session identifier (PSID), destination mobile station identifier, and virtual channel identifier, and loads user packet data or SSCS control data into the payload. If it is transmitted to the AAL5 CPCS, the multiplexing procedure and the transmission procedure are completed. Therefore, the SSCS-PDU data block that arrives at the destination wireless network controller via the mobile packet router (MPR) through the virtual channel is demultiplexed by the receiving SSCS to confirm the identifier of the destination mobile station, and the received data is transmitted or , an operation corresponding to the SSCS control data is performed.</p><p>2) When the mobile station in the radio network controller area transmits packet data having a specific service option and a packet session identifier by designating a specific packet data node identifier, the originating radio network controller/packet controller (RNC/PCF) Verifies the virtual channel identifier with the corresponding packet data node from the data node identifier, and SSCS receives the source identifier, service option, packet session identifier, packet data node identifier, and virtual channel identifier stored in the packet controller (PCF). When the PDU header is created and user packet data or SSCS control data is loaded in the payload and delivered to the AAL5 CPCS, the multiplexing and transmission procedures are completed. Accordingly, the SSCS-PDU data block arriving at the packet data node via the mobile packet router through the virtual channel is demultiplexed by the receiving SSCS, the source mobile station identifier is confirmed, and delivered to the destination of the received data, or corresponds to the SSCS control data. procedure will be carried out. </p><p>Packet data received from a specific packet data node to a mobile terminal can be generated only for a mobile station that has already been registered in the corresponding packet data node, and the packet data node uses the virtual data Channel identifier and packet data node's SSCS to create SSCS-PDU header Multiplexing is achieved by providing one information transmit</p><p>3) When the mobile station in the area of the radio network controller requests an Internet/packet network connection data service with a specific service option and packet session identifier and data is received, the originating radio network controller/packet controller (RNC/PCF) If it is already registered in the packet controller (PCF) by checking the corresponding service option and PS identifier of the mobile station, the received user packet data and the virtual channel identifier connected to the packet data node connected in advance are transmitted to the SSCS so that the SSCS is multiplexed. send If it is not registered in the packet controller (PCF), the packet controller (PCF) regards it as a new packet registration, and the packet controller (PCF) decides whether to receive the packet data node identifier to be routed from the packet call controller, and the corresponding packet data node Checking the virtual channel identifier associated with the identifier, SSCS receives the service option, packet session identifier, and virtual channel identifier stored in the packet controller (PCF), creates an SSCS-PDU header, and payloads user packet data or control data of SSCS. The multiplexing procedure and the transmission procedure are completed when it is transmitted to the AAL5 CPCS. Therefore, the SSCS-PDU data block arriving at the packet data node via the mobile packet router through the virtual channel is demultiplexed by the receiving side SSCS and the source mobile station identifier is confirmed to transmit the received data, or a procedure corresponding to the SSCS control data. is made</p><p>Here, the packet data received from the packet data node to the mobile terminal is It can be generated only for mobile stations registered in advance in the corresponding packet data node, and the packet data node receives the virtual channel identifier of the destination packet and the SSCS of the packet data node from the table that relates the address of the incoming packet to the mobile station. Multiplexing is performed by providing information for creating a header, and when the multiplexed SSCS-PDU data block is delivered to the AAL5 CPCS, it is delivered to the called AAL5 CPCS through a virtual channel. Forward packet data.</p><p>In the three cases described above, the virtual channel between the wireless network controller and the wireless network controller that delivers the user packet data, and the virtual channel between the wireless network controller and the packet data node, can always be set by the fixed virtual channel (PVC) method. The radio network controller/packet controller (RNC/PCF) opens a virtual channel for all counterpart node identifiers in the virtual channel table it owns, and the counterpart radio network controller node identifier or packet data node identifier to which the virtual channel identifier is connected. records are kept. </p><p>On the other hand, when the virtual channel is set by the circuit-switched virtual channel (CVC) method, the ATM switch is activated only when the radio network controller/packet controller (RNC/PCF) needs to transmit user packet data with the counterpart node identifier. A method of opening a virtual channel based on the signaling used and releasing the virtual channel when there is no data transmission with the other node is used. Only when there is no virtual channel identifier with the counterpart node identifier, a new one is opened and registered in the virtual channel table at the same time. As a result, packet data of other subsequent terminals can be multiplexed through an already set virtual channel, and when there is no data transmission for more than a specified time between the nodes connected by the virtual channel, the corresponding virtual channel is released.</p><p>In the third case among the above-described cases, when accessing the Internet using a PPP link and a packet data node for a terminal for transmitting a mobile packet, the payload packet identifier (PPID) of the SSCS-PDU header contains a delimiter that separates the PPP links. In this case, depending on the packet service status of the terminal, the SSCS of the wireless network controller to which the terminal belongs and the SSCS of the packet data node connected to the PPP link of the terminal exchange control information to maintain the PPP link and service continuously. to be able to provide</p><p>Accordingly, when the mobile station accesses the Internet through the packet data node, the packet data node allocates the Internet protocol address (IP address) in its Internet subnetwork identifier to the mobile station as the home Internet protocol address (Home IP address) of the mobile station. or as a Care of Address (COA) for Mobile Internet Protocol service. Therefore, if the mobile station registers with a new packet data node when handoff or roaming while the Internet packet service is active, the mobile station must receive a new home Internet protocol address or COA. Disconnection of services may occur due to time consumption of link re-establishment and time consumption of mobile Internet protocol (IP) registration.</p><p>Thus, as long as the mobile station keeps the Internet packet service active, the mobile Even if the station moves to another wireless network controller area, it continuously maintains a virtual channel with the initially registered packet data node so that the home Internet Protocol (IP) address can be used continuously to provide a packet data service without interruption. In order to be executed, the SSCS of the wireless network controller and the SSCS of the packet data node must have a control signal to update the routing path of the mobile station, and at the same time have a registration control function to the packet data node, a cellular packet flow control function, and the like. </p><p>The configurations of the SSCS control block and the PPP data block delivered as the SSCS-PDU payload are shown in FIGS. 10A to 10B. </p><p>Referring to FIG. 10A , the control block includes a control message identifier field for discriminating the contents of a control message, a message sequence field for indicating the order of the control message, and a request/response field for discriminating a request and response of a control message. It consists of a control message header consisting of </p><p>On the other hand, the PPP data block consists of one PPP frame as shown in FIG. 10B.</p><p>At this time, the control message of the SSCS is, as shown in FIG. 11, the registration of the mobile station, the location update, the PPP link data flow control, the wireless connection state of the mobile station, and the Internet protocol ( IP) quality of service (QoS), billing data information, etc. may be present.</p><p>Here, the mobile station registration is when the mobile station requests Internet access for the first time after power-on or when the mobile station requests Internet access, but the wireless network controller registers with a packet data node that cannot establish a virtual channel connection. , and when the mobile station needs to register as a packet data node that is not registered, the SSCS of the wireless network controller is the SSCS of the packet data node, the wireless QoS of the mobile station, and the flow control option between SSCS. A registration request control data block including variables such as etc. is first transmitted and a response from the packet data node is received. After receiving a response from the packet data node, the wireless network controller transmits the user's PPP link data to the packet data node through the payload of SSCS. When the packet data node receives the mobile station registration message, it sends an authentication signal (Ack.), and then begins to deliver PPP data for LCP setup with the corresponding mobile station in the SSCS-PDU payload.</p><p>Also, location update is a control message used when the mobile station moves from the area of the old RNC to the area of the new RNC. From the packet call controller (LMF), which manages the link mobility binding table, the mobile station finds out the packet data node identifier previously registered and delivers the message through a virtual channel connecting the packet data node. </p><p>On the other hand, the location update message makes the service option and packet session identifier of the SSCS-PDU header invalid (Null) when the mobile station is in the dormant state. packet data node receives From the virtual channel identifier obtained, the moving location indicating which radio network controller the mobile station has moved to is identified.</p><p>On the other hand, the PPP link data flow control performs "congestion ON" when the packet buffer in the wireless network controller exceeds the threshold. Sends a meaningful message, at which time the packet data node returns to "congestion OFF" It does not send data to the wireless network controller until a meaningful message arrives.</p><p>When the wireless connection status and Internet protocol service quality of the mobile station change from dormant state to active state, and when it is necessary to send service options and packet session identifiers, or when the radio quality of service is changed, the radio network controller transmits to the packet data node , the packet data node transmits when it needs to inform the wireless network controller of the Internet Protocol service quality of the terminal.</p><p>On the other hand, billing data information is transmitted from the wireless network controller to the packet data node or from the packet data node at the request of the other party or when an event that requires the delivery of the billing data of the terminal occurs. It transmits to the wireless network controller. The content of the control message body carries billing information information.</p>

<p>According to the present invention as described above, in a cellular packet ATM network that transmits packet data of a mobile terminal based on an ATM switch, between all wireless network controllers and wireless network controllers to which packets of mobile terminals are terminated, or all wireless Establish a virtual channel between the network controller and all packet data nodes, and if a packet path is to be assigned between the radio network controller and the radio network controller or between the radio network controller and the packet data node, select the radio network controller or packet data node. By multiplexing/demultiplexing a packet call or packet session for an individual mobile terminal to a connected virtual channel, there is an effect of allocating a sufficient packet path to one virtual channel. In addition, when allocating a packet path, there is no need to perform signaling processing for setting a packet forwarding path of each mobile terminal.</p>