JP5040573B2 - Wireless access point and wireless relay method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide technology of a radio access point which reduces consumption of a battery of a radio telephone terminal, and continues communication without delay when the radio telephone terminal moves between radio access points. <P>SOLUTION: A radio LAN access point 3 changes a multicast address of the radio telephone terminal 2 waiting for a music packet to a predetermined multicast address associated with the kind of the music packet to be received by the radio telephone terminal 2. Further, the radio LAN access point changes the multicast address of the music packet received by a main device 1 to the predetermined multicast address associated with the kind of the multicast packet, then, performs radio transmission. Furthermore, the radio LAN access point previously notifies other radio LAN access point 3 of existence of the radio telephone terminal waiting for the music packet. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a relay technology between a main apparatus and a wireless terminal.

  In a wireless telephone system using the IEEE802.11 wireless LAN technology, when a wireless access point that relays between a main apparatus and a wireless telephone terminal receives a unicast packet addressed to the wireless telephone terminal from the main apparatus, a TIM (Traffic Indication) A beacon including Map) is transmitted. Thereafter, when receiving a PS-POLL signal for requesting transmission of a packet addressed to the wireless telephone terminal from the wireless telephone terminal, the wireless access point wirelessly transmits the unicast packet to the wireless telephone terminal. When the wireless access point receives a multicast packet from the main device, the wireless access point transmits a beacon including DTIM (Delivery Traffic Indication Message), and then wirelessly transmits the received multicast packet. Note that the DTIM is periodically included in a beacon and transmitted wirelessly.

  On the other hand, a radio telephone terminal normally uses a power saving mode when waiting. In the power saving mode, the wireless telephone terminal periodically shifts from the sleep state to the awake state, and receives the beacon of the wireless access point. Then, by analyzing the TIM included in the received beacon, it is determined whether or not packets addressed to the own wireless telephone terminal are stored in the wireless access point. When packets addressed to the own wireless telephone terminal are stored in the wireless access point, the awake state is maintained, a PS-POLL signal is transmitted to the wireless access point, and the unicast addressed to the own wireless telephone terminal is transmitted from the wireless access point. Receive the packet. When packets addressed to the own wireless telephone terminal are not stored in the wireless access point, the state is quickly shifted from the awake state to the sleep state. Further, when DTIM is included in the received beacon, awake is maintained and a multicast packet is received from the wireless access point.

  Patent Document 1 discloses a wireless LAN system that can reduce useless wireless transmission. In this wireless LAN system, a wireless access point (master station device) manages subordinate wireless telephone terminals (slave station devices). When the multicast packet received from the main apparatus (host) is a packet addressed to a group other than the group to which the subordinate radio telephone terminal belongs, the wireless access point discards the packet without wireless transmission. By doing so, useless wireless transmission is reduced.

JP 2000-324120 A

However, in the technique described in Patent Document 1, when a subordinate radio telephone terminal belongs to the destination group of the multicast packet received from the main device, the wireless access point transmits the received multicast packet by radio. The subordinate radio telephone terminals in the power saving mode store the necessary information until the sleep state is canceled in the multicast packet transmitted from the radio access point to the group to which the own radio telephone terminal belongs. Even if not, the awake state is maintained to receive this packet. For this reason, the battery is wasted.
In addition, it is not considered when there are a plurality of the same wireless access points.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to reduce the battery consumption of a wireless telephone terminal, and when the wireless terminal moves between wireless access points while receiving multicast packets. In addition, a wireless access point technology capable of continuing to receive multicast packets without delay is provided.

  In order to solve the above-described problem, in the present invention, a multicast address of a wireless terminal that is waiting to receive a multicast packet is assigned a predetermined multicast address associated with the type of multicast packet that the wireless terminal is waiting to receive. Change to Further, the multicast address of the multicast packet received from the main device is changed to a predetermined multicast address associated with the type of the multicast packet, and then wirelessly transmitted. Further, the wireless terminal that is in a reception waiting state and the type of multicast packet that the wireless terminal is waiting to receive are transmitted to the wired network and notified to other wireless access points.

For example, the present invention is a wireless access point that relays the packetized data comprises multicast packets between the wireless terminal that is connected to the main device and the wireless network connected to the wired network, the multicast an address storing means for storing in association with the type and the multicast address of the multicast packets of the packet, if the radio access point contains the call control information to the data to be relayed, a particular type from the call control information a reception waiting end end detecting means for detecting a radio terminal waiting for reception of a multicast packet, stored in a wireless terminal pre-Symbol reception waiting end end detecting means detects the multicast address of the wireless terminal to the address storage means change to the multicast address corresponding to the specific type described As an address change instruction unit that instructs, when receiving the multicast packet according the previous SL main unit to said particular type to be transmitted to the wireless terminal, multicast has been specified multicast address of a multicast packet received by the multicast address change instruction means and multicast address change transmission means for transmitting before Symbol radio terminal by changing the address, the type of the multicast packet in which the address storage means for storing, the multicast address and the reception waiting terminal detecting means for transmitting the multicast packet as a detection address the access point information of the wireless terminal of the multicast packet reception waiting was, and the access point information notifying means for notifying the other radio access points, Accession from other wireless access points When the access point information is received, other access point information storage means for storing the access point information, and when the wireless terminal related to the access point information belongs to the own wireless access point, the multicast address change is performed from the stored access point information. and other access point information setting means for performing the transmission means, characterized by having a.

  According to the present invention, a multicast packet received from the main apparatus can be received only by a wireless terminal that is waiting to receive the same type of multicast packet as the multicast packet. Thereby, the duration of the awake state in the wireless terminal in the power saving mode can be shortened, and the battery consumption of the wireless terminal can be reduced. Even if the wireless terminal moves between the wireless access points, it is possible to continue receiving multicast packets.

  Embodiments of the present invention will be described below. Here, an application example to a wireless telephone system including a wireless telephone terminal as a wireless terminal will be described.

  FIG. 1 is a schematic configuration diagram of a radiotelephone system to which an embodiment of the present invention is applied.

  As shown in the figure, the radio telephone system of the present embodiment includes a main apparatus (or server) 1, a plurality of radio telephone terminals 2 accommodated in the main apparatus 1, and the main apparatus 1 and a wireless LAN 5 that is a self-control area. A wireless LAN access point 3 that relays between the wireless telephone terminals 2 belonging to (Local Area Network), and a wired LAN 4 that interconnects the main device 1 and the wireless LAN access point 3.

  The main device 1 has a function as a call control server of the radio telephone terminal 2. Also, the main device 1 sends out a packet storing sound information such as a ring tone, DT (Dial Tone), RBT (Ringing Back Tone), BT (Busy Tone), hold tone and the like on the wired LAN 4 by multicast. Hereinafter, this multicast packet is referred to as a musical tone packet.

  The wireless telephone terminal 2 receives and processes the unicast packet addressed to its own wireless telephone terminal transmitted from the wireless LAN access point 3 and the multicast packet addressed to the group to which the own wireless telephone terminal belongs. Here, the radio telephone terminal 2 operates in one of an operation mode of an active mode and a power saving mode.

  In the present embodiment, the wireless LAN access point 3 is composed of a plurality of units (3-1, 3-2), and the wireless telephone terminal 2-1 is a wireless LAN 5-point that is a jurisdiction area of the wireless LAN access point 3-1. The wireless telephone terminal 2-2 is a wireless telephone terminal that belongs to the wireless LAN 5-2, which is the area under the control of the wireless LAN access point 3-2.

  In the active mode, the radio telephone terminal 2 is always in an awake state, and a unicast packet addressed to the own radio telephone terminal wirelessly transmitted from the wireless LAN access point 3 and a multicast addressed to the group to which the own radio telephone terminal belongs. Receive the packet.

  In the power saving mode, the wireless telephone terminal 2 periodically shifts from the sleep state to the awake state and receives the beacon of the wireless LAN access point 3. Then, by analyzing the TIM included in the received beacon, it is determined whether or not packets addressed to the own wireless telephone terminal are accumulated in the wireless LAN access point 3. When packets addressed to the own wireless telephone terminal are stored in the wireless LAN access point 3, the awake state is maintained, a PS-POLL signal is transmitted to the wireless LAN access point 3, and the wireless LAN access point 3 Receives a unicast packet addressed to a wireless telephone terminal. On the other hand, if it is determined that the wireless LAN access point 3 does not store packets addressed to its own wireless telephone terminal, the wireless LAN access point 3 immediately shifts from the awake state to the sleep state. Further, when the received beacon includes DTIM, the wireless telephone terminal 2 maintains awake and receives a multicast packet from the wireless access point.

  Further, the radio telephone terminal 2 changes the multicast address of the group to which the own radio telephone terminal belongs in accordance with the multicast address change instruction received from the wireless LAN access point 3.

  In the present embodiment, the wireless telephone terminal 2 switches the belonging from the wireless LAN access point 3-1 to the wireless LAN access point 3-2 or from the wireless LAN access point 3-2 to the wireless LAN access point 3-1. Are executed according to the wireless LAN handover procedure.

  FIG. 2 is a schematic functional block diagram of the radio telephone terminal 2.

  As shown in the figure, the wireless telephone terminal 2 includes a wireless LAN packet transmission / reception unit 201, a beacon reception unit 202, an MM (MAN MACHINE) interface unit 203, an operation mode control unit 204, an operation mode setting unit 205, a communication A protocol processing unit 206 and a multicast address changing unit 207 are included.

  The wireless LAN packet transmission / reception unit 201 has an interface control function for the wireless LAN 5 and transmits / receives packets to / from the wireless LAN access point 3 via the wireless LAN 5.

  The beacon receiving unit 202 receives a beacon periodically transmitted by the wireless LAN access point 3 via the wireless LAN packet transmitting / receiving unit 201.

  The MM interface unit 203 is an interface for presenting information to the user and receiving information from the user, a voice input / output unit such as a speaker and a microphone, a display unit such as an LCD display and an LED display, and an input key And so on.

  The operation mode control unit 204 controls the operation mode of the radio telephone terminal 2. As described above, the operation modes of the radio telephone terminal 2 include the active mode and the power saving mode.

  The operation mode setting unit 205 sets the operation mode of the wireless telephone terminal 2 in the operation mode control unit 204.

  The communication protocol processing unit 206 processes the communication protocol (call control protocol such as SIP (Session Initiation Protocol) and data transmission protocol such as RTP (Real Time Transfer Protocol)) of the wireless telephone terminal 2. Thereby, communication control of the radio telephone terminal 2 and encoding / decoding of call data are performed.

  The multicast address changing unit 207 determines the multicast address of the group to which the own wireless telephone terminal belongs in accordance with the multicast address changing instruction stored in the unicast packet received from the wireless LAN access point 3 via the wireless LAN packet transmitting / receiving unit 201. change.

  FIG. 3 is a diagram for explaining an operation flow of the radio telephone terminal 2 in the power saving mode. Note that the operation flow in the active mode is the same as that of an existing wireless telephone terminal, and thus detailed description thereof is omitted.

  When the predetermined beacon reception timing is reached (“YES” in S101), the operation mode control unit 204 shifts the own wireless telephone terminal from the sleep state to the awake state (S102). As a result, the beacon receiving unit 202 receives a beacon periodically transmitted from the wireless LAN access point 3 (S103).

  Next, the beacon receiving unit 202 analyzes the beacon (S104).

  As a result of this analysis, the TIM included in the received beacon indicates that the packet addressed to the own wireless telephone terminal is not accumulated in the wireless LAN access point 3, and the received beacon does not include DTIM. In the case (“None” in S104), the beacon receiving unit 202 notifies the operation mode control unit 204 to that effect. In response to this, the operation mode control unit 204 promptly shifts the own wireless telephone terminal from the awake state to the sleep state (S111), and returns to S101.

  If the received beacon includes DTIM as a result of this analysis (“DTIM has a multicast address of the own wireless telephone terminal group” in S104), the beacon receiving unit 202 transmits a wireless LAN packet transmission / reception to that effect. Notification to the unit 201. In response to this, the awake state is maintained, and the wireless LAN packet transmission / reception unit 201 receives a multicast packet addressed to the multicast address of the group to which the own wireless telephone terminal belongs from the wireless LAN access point 3. wait. When a multicast packet destined for the multicast address of the group to which the own wireless terminal belongs is received (S105), it is passed to the communication protocol processing unit 206. In response to this, the communication protocol processing unit 206 responds to the contents of the packet (call control packet such as SIP, data transmission packet such as RTP) stored in the payload of the multicast packet received from the wireless LAN packet transmission / reception unit 201. The process is performed (S106). Thereafter, the operation mode control unit 204 shifts the own wireless telephone terminal from the awake state to the sleep state (S111), and returns to S101.

  Also, as a result of this analysis, when the TIM included in the received beacon indicates that packets addressed to the own wireless telephone terminal are stored in the wireless LAN access point 3 (" The beacon receiving unit 202 notifies the wireless LAN packet transmitting / receiving unit 201 to that effect. In response to this, the awake state is maintained, and the wireless LAN packet transmitting / receiving unit 201 transmits a PS-POLL signal to the wireless LAN access point 3, and from the wireless LAN access point 3, the wireless LAN packet transmission / reception unit 201 sets the destination to the own wireless telephone terminal. A cast packet is received (S107). Then, the wireless LAN packet transmitting / receiving unit 201 analyzes the received unicast packet and checks whether this unicast packet stores a multicast address change instruction (S108).

  When a multicast address change instruction is stored (“YES” in S108), the wireless LAN packet transmission / reception unit 201 passes this multicast address change instruction to the multicast address change unit 207. In response to this, the multicast address change unit 207 In accordance with the multicast address change instruction received from the wireless LAN packet transmitting / receiving unit 201, the multicast address of the group to which the own wireless telephone terminal belongs is changed to the multicast address designated by this multicast address change instruction (S109). The multicast address changing unit 207 transmits a change completion notification packet to the wireless LAN access point 3 via the wireless LAN packet transmitting / receiving unit 201 (S110). Control unit 204 is shifted to the sleep state the radio telephone terminal from an awake state (S 111), the flow returns to S101.

  On the other hand, when the multicast address change instruction is not stored in the unicast packet received from the wireless LAN access point 3 in S108 (“NO” in S108), the wireless LAN packet transceiver 201 transmits the unicast packet to the communication protocol. In response to this, the communication protocol processing unit 206 receives the packet (call control packet such as SIP, data such as RTP) stored in the payload of the unicast packet received from the wireless LAN packet transmission / reception unit 201. (S106) After that, the operation mode control unit 204 shifts the own wireless telephone terminal from the awake state to the sleep state (S111), and returns to S101.

  Returning to FIG. 1, the description will be continued.

  When receiving the unicast packet from the main device 1, the wireless LAN access point 3 transmits a beacon including the TIM. Thereafter, when a PS-POLL signal is received from the wireless telephone terminal 2 specified by the destination address of the unicast packet, the unicast packet is wirelessly transmitted.

  In addition, when receiving a multicast packet from the main apparatus 1, the wireless LAN access point 3 transmits a beacon including DTIM, and then wirelessly transmits the multicast packet. Here, when the multicast packet received from the main device 1 is a musical tone packet, the wireless LAN access point 3 determines the multicast address of the musical tone packet in advance according to the type of sound information stored in the musical tone packet. Change to the specified multicast address.

  Note that the DTIM is periodically included in a beacon and transmitted wirelessly.

  In addition, the wireless LAN access point 3 detects the wireless telephone terminal 2 that is waiting to receive a musical sound packet, together with the type of sound information stored in the musical sound packet that the wireless telephone terminal 2 is waiting to receive.

  In addition, the wireless LAN access point 3 transmits the type of sound information and the wireless telephone terminal 2 waiting to receive the detected musical sound packet to the wired network as terminal information notification.

  Further, even when the wireless telephone terminal 2 is no longer waiting to receive a musical tone packet, the wireless LAN access point 3 transmits that fact as a terminal information notification to the wired network.

  The wireless LAN access point 3-2 that has received the terminal information notification is whether or not the wireless telephone terminal 2 existing under the other wireless LAN access point 3-1 is waiting to receive a musical sound packet, and if it is waiting for reception. Know if you are waiting to receive a musical sound packet.

  The wireless LAN access point 3-2 refers to the terminal information notification when any of the wireless telephone terminals 2 notified by the terminal information notification is handed over. Send a multicast packet.

  FIG. 4 is a schematic diagram of the wireless LAN access point 3.

  As illustrated, the wireless LAN access point 3 includes a wired LAN packet transmission / reception unit 301, a wireless LAN packet transmission / reception unit 302, a beacon transmission unit 303, an upstream relay unit 304, a downstream relay unit 305, and a multicast address storage unit. 306, musical tone packet reception waiting terminal detection unit 307, terminal state storage unit 308, multicast address change instruction unit 309, terminal information notification detection unit 310, and terminal information notification transmission unit 311.

  The wired LAN packet transmission / reception unit 301 has a wired LAN 4 interface control function, and transmits and receives packets to and from the main apparatus 1 via the wired LAN 4.

  The wireless LAN packet transmission / reception unit 302 has an interface control function of the wireless LAN 5 and transmits / receives packets to / from the wireless telephone terminal (subordinate wireless telephone terminal) 2 managed by the own access point 3 via the wireless LAN 5.

  The beacon transmission unit 303 periodically transmits a beacon for notifying the subordinate wireless telephone terminal 2 of the jurisdiction area (wireless LAN 5) of the wireless LAN access point 3 via the wireless LAN packet transmission / reception unit 302.

  The upstream relay unit 304 relays (bridges) the packet received from the wireless telephone terminal 2 under the control of the wireless LAN packet transmission / reception unit 302 to the wired LAN packet transmission / reception unit 301.

  The downlink relay unit 305 relays (bridges) the packet received by the wired LAN packet transmission / reception unit 301 from the main apparatus 1 to the wireless LAN packet transmission / reception unit 302. Here, when the packet received from the main apparatus 1 is a musical tone packet, the downlink relay unit 305 refers to the terminal state storage unit 308, and is a wireless telephone terminal that is waiting to receive a musical tone packet of the same type as the musical tone packet. Check whether there is two. If there is such a radio telephone terminal 2, the multicast address storage unit 306 is referred to, the destination address of the musical tone packet is changed to a multicast address registered in advance in association with the type of musical tone packet, Then, the musical tone packet is relayed to the wireless LAN packet transmitting / receiving unit 302. On the other hand, if there is no such wireless telephone terminal 2, the musical tone packet is discarded without being relayed to the wireless LAN packet transmitting / receiving unit 302. Further, when the radio telephone terminal 2 is handed over from another radio access point 3, the radio telephone terminal 2 is in a state of waiting for reception of the same kind of musical sound packet as referring to the terminal state storage unit 308. Check whether or not. When handover is performed when there is no radio telephone terminal 2 receiving the musical tone packet, the musical tone packet that has been discarded so far is stopped being discarded, and the destination address of the musical tone packet is changed to this A multicast address associated with the type of the musical tone packet is changed to a pre-registered multicast address, and then the musical tone packet is relayed to the wireless LAN packet transmitting / receiving unit 302.

  The multicast address storage unit 306 stores, for each type of musical tone packet, a multicast address for receiving that type of musical tone packet. FIG. 5 is a diagram schematically illustrating an example of registered contents in the multicast address storage unit 306. As illustrated, the multicast address storage unit 306 stores a record 3060 for each type of musical sound packet. A record 3060 includes a field 3061 for registering the type of musical tone packet such as “hold tone”, “ring tone”, “RBT”, “BT”, “DT”, and a multicast address for receiving the musical tone packet. And a field 3062 for registration.

  The musical tone packet reception waiting terminal detection unit 307 monitors the upstream relay unit 304 and the downstream relay unit 305, and for each wireless telephone terminal 2, based on the call control packet transmitted / received by the wireless telephone terminal 2 to / from the main apparatus 1, Whether or not the telephone terminal 2 is waiting to receive a musical sound packet, and the types of musical sound packets that the wireless telephone terminal 2 is waiting to receive when the wireless telephone terminal 2 is waiting to receive a musical sound packet Is detected.

  The terminal information notification detection unit 310 monitors the downlink relay unit 305, detects terminal information transmitted from the other wireless access point 3, and stores it in the terminal state storage unit 308.

  The terminal information notification transmission unit 311 transmits terminal information under the management of its own wireless access point to the wired LAN 4 using the uplink relay unit 304 together with its own address.

  Here, for example, a determination table as shown in FIG. 6 is used to detect the reception state of the musical tone packet and to detect the type of musical tone packet waiting to be received. In FIG. 6, column 3071 indicates the type of the musical tone packet, and column 3072 indicates an event (call control packet of the call control packet) for detecting that the reception state of the musical tone packet of the type registered in the column 3071 on the same line has started. Column 3073 shows an event (call control packet exchange) for detecting that the reception state of the musical tone packet of the type registered in the column 3071 on the same line has stopped.

  According to the example shown in FIG. 6, the start of the reception waiting state for the tone packet of the ring tone is detected when the wireless telephone terminal 2 receives the INVITE packet from the main apparatus 1, and the stop is detected by the wireless telephone terminal 2. It is detected by transmitting a 200 OK (off-hook) packet to the main apparatus 1. The start of the DT tone packet reception waiting state is detected when the wireless telephone terminal 2 transmits an INVITE packet to the main apparatus 1, and the stop is detected when the wireless telephone terminal 2 transmits a dial information packet to the main apparatus 1. Detected by sending. In addition, the start of the reception waiting state of the RBT tone packet is detected when the radio telephone terminal 2 receives the 180 Ringing packet from the main apparatus 1, and the stop is received by the radio telephone terminal 2 from the main apparatus 1. Is detected. The start of the BT tone packet reception wait state is detected when the wireless telephone terminal 2 receives the BYE packet from the main apparatus 1, and the stop is transmitted by the wireless telephone terminal 2 to the main apparatus 1. Is detected. In addition, the start of the reception waiting state for the musical tone packet of the holding tone is detected by the radio telephone terminal 2 transmitting the holding tone request packet to the main apparatus 1, and the stop is detected by the radio telephone terminal 2 from the main apparatus 1. It is detected by receiving a music on hold release packet.

  The terminal state storage unit 308 determines whether or not each wireless telephone terminal 2 is in a standby state for receiving a musical tone packet, and if this wireless telephone terminal 2 is in a standby state for receiving a musical tone packet, The type of musical tone packet waiting to be received is registered. The terminal state storage unit 308 also registers the state of the terminal waiting for reception of a musical tone packet under the control of another wireless LAN access point 3 detected by the terminal information notification detection unit 310. Further, the state of the wireless telephone terminal 2 stored in the terminal state storage unit 308 is transmitted to the wired network by the terminal information notification transmission unit.

  FIG. 7 is a diagram schematically illustrating an example of registered contents in the terminal state storage unit 308. As illustrated, a record 3080 is registered in the terminal state storage unit 308 for each wireless access point 3 including its own wireless access point. A record 3080 indicates a field 3081 in which the address of the wireless LAN access point 3 is registered, a field 3082 in which the address of the wireless telephone terminal 2 is registered, and whether or not the wireless telephone terminal 2 is waiting to receive a musical tone packet. A field 3083 for registering information, and a field 3084 for registering the type of a musical tone packet that the wireless telephone terminal 2 is waiting to receive when the wireless telephone terminal 2 is in a reception state of the musical sound packet; Have

  The multicast address change instructing unit 309 refers to the terminal state storage unit 308 to detect the radio telephone terminal 2 whose reception state of the musical tone packet has been changed, and a multicast address whose destination is the detected address of the radio telephone terminal 2 A packet storing the change instruction is generated and transferred to the wireless LAN packet transmitting / receiving unit 302. Specifically, when the record 3080 in which the registered content (waiting reception of the musical tone packet) in the field 3083 is changed from “No” to “Yes” is detected, the unicast address registered in the field 3083 of this record 3080 To the destination address of the packet. Further, the record 3060 is searched from the multicast address storage unit 306 using the type registered in the field 3084 of the record 3080 as a key. Then, a multicast address change instruction for instructing change to the multicast address registered in the field 3062 of the searched record 3060 is stored in this packet, and this packet is passed to the wireless LAN packet transmitting / receiving unit 302.

  Next, with respect to the wireless LAN access point 3 having the above-described configuration, an operation in the case of instructing the subordinate wireless telephone terminal 2 to change the multicast address (multicast address change instruction operation), and a packet received from the wired LAN 4 are transmitted to the wireless LAN 5 Next, an operation when relaying to the network (referred to as downlink relay operation) will be described. Note that an operation when a packet received from the wireless LAN 5 is relayed to the wired LAN 4 (referred to as an uplink relay operation) is the same as the uplink relay operation of an existing wireless LAN access point, and a description thereof will be omitted.

  FIG. 8 is a flowchart for explaining the multicast address change instruction operation of the wireless LAN access point 3.

  The musical tone packet reception waiting terminal detection unit 307 monitors the upstream relay unit 304 and the downstream relay unit 305, and detects whether the upstream relay unit 304 or the downstream relay unit 305 relays the call control packet (S201). If the uplink relay unit 304 or the downlink relay unit 305 relays the call control packet (“YES” in S201), the tone packet reception waiting terminal detection unit 307 determines that the relay operation of the call control packet is in a tone packet reception waiting state. It is determined whether or not the event corresponds to a start event (see FIG. 6) (S202).

  Specifically, when the relay action of the call control packet is the downlink relay operation of the INVITE packet by the downlink relay unit 305, this action is triggered by a reception wait state start event “INVITE packet reception” of the tone packet storing the ring tone. Judge as applicable. If the relay action of the call control packet is an upstream relay operation of the INVITE packet by the upstream relay unit 304, it is determined that this action corresponds to the reception wait state start event “INVITE packet transmission” of the tone packet storing DT. . When the relay action of the call control packet is a downlink relay operation of the 180 Ringing packet by the downlink relay unit 305, it is determined that this operation corresponds to the reception wait state start event “180 Ringing packet reception” of the music packet storing the RBT. . When the relay action of the call control packet is a downlink relay operation of the BYE packet by the downlink relay unit 305, it is determined that this action corresponds to the reception wait state start event “BYE packet reception” of the music packet storing the BT. . When the relay action of the call control packet is the upstream relay operation of the hold sound request packet by the upstream relay unit 304, this action is the reception wait state start event “send hold sound request packet transmission” of the tone packet storing the hold sound. It is judged that it corresponds to.

  If it is determined in S202 that the relay action of the call control packet corresponds to a music packet reception waiting state start event (“YES” in S202), the music packet reception waiting terminal detection unit 307 determines that the call control packet is a downlink relay unit. If the call control packet is relayed downstream by 305, the destination address of the call control packet is used as a key. If the call control packet is relayed upstream by the upstream relay unit 304, the call control packet transmission source The record 3080 is searched from the terminal state storage unit 308 using the address as a key, and the reception waiting state represented by the information registered in the field 3082 of the searched record 3080 is checked. If the acquired information is information indicating that it is not waiting for reception of a musical tone packet ("No" in FIG. 7) (YES in S203), the process proceeds to S204, and information indicating that it is waiting for reception of a musical tone packet ( In the case of “Yes” in FIG. 7 (NO in S203), the process returns to S201.

  In S204, the musical tone packet reception waiting terminal detection unit 307 indicates that the information registered in the field 3082 of the record 3080 searched in S203 is in a standby state from “No” indicating that it is not in a reception standby state. In addition to changing to “Yes”, in the field 3083 of this record 3080, the musical tone packet type (see FIG. 6) associated with the corresponding musical tone packet reception waiting state start event is registered.

  The multicast address change instructing unit 309 indicates that the information registered in the field 3082 of the record 3080 searched in S203 is “No” indicating that the information is not in the standby state, and “Yes” indicating that the information is in the standby state. If it is detected that the record 3060 has been changed, the record 3060 is searched from the multicast address storage unit 306 using the musical tone packet type registered in the field 3083 of the record 3080 as a key. Then, a multicast address change instruction for instructing change to the multicast address registered in the field 3062 of the searched record 3060 is generated (S205).

  Then, the multicast address change instruction unit 309 generates a packet storing the multicast address change instruction generated in S205 with the address registered in the field 3081 of the record 3080 searched in S203 as a destination. Then, this packet is transmitted from the wireless LAN packet transmitting / receiving unit 302 to the wireless LAN 5 (S210).

  That is, the multicast address change instruction unit 309 passes the generated packet to the wireless LAN packet transmission / reception unit 302. In response to this, the wireless LAN packet transmitting / receiving unit 302 controls the beacon transmitting unit 303 to transmit a beacon including a TIM. Thereafter, when a PS-POLL signal is received from the wireless telephone terminal 2 specified by the destination address of the generated packet, the generated packet is wirelessly transmitted.

  Next, if a multicast address change completion notification packet is received from the wireless telephone terminal 2 that is the destination of the packet (“YES” in S211), terminal information is transmitted on the wired network (S212), and the process returns to S201.

  On the other hand, if it is determined in S202 that the relay action of the call control packet does not correspond to the music packet reception wait state start event ("NO" in S202), the music packet reception wait terminal detection unit 307 It is determined whether or not the relay action corresponds to a music packet reception wait state stop event (see FIG. 6) (S206).

  Specifically, when the relay action of the call control packet is an upstream relay operation of the 200 OK packet by the upstream relay unit 304, this action is a “waiting state reception event stop event“ 200 OK (off-hook) packet transmission ”storing the ring tone. ”Or a reception of a musical tone packet reception waiting state“ 200 OK packet transmission ”storing BT. When the relay action of the call control packet is the uplink relay operation of the dial information packet by the upstream relay unit 304, this action corresponds to the reception stop state “dial information packet transmission” of the tone packet storing DT. to decide. If the relay action of the call control packet is a 200 OK packet downlink relay operation by the downlink relay unit 305, it is determined that this action corresponds to the reception stop state “200 OK packet reception” event of the tone packet storing the RBT. . When the relay action of the call control packet is a downlink relay operation of the hold tone release packet by the downlink relay unit 305, this action is performed in the reception wait state stop event “hold release packet reception” of the tone packet storing the hold tone. Judge as applicable.

  If it is determined in S206 that the call control packet relaying action corresponds to a music packet reception waiting state stop event ("YES" in S206), the music packet reception waiting terminal detection unit 307 determines that the call control packet is transmitted to the downlink relay unit. If the call control packet is relayed downstream by 305, the destination address of the call control packet is used as a key. If the call control packet is relayed upstream by the upstream relay unit 304, the call control packet transmission source The record 3080 is searched from the terminal state storage unit 308 using the address as a key, and the reception waiting state represented by the information registered in the field 3082 of the searched record 3080 is checked (S207). If the acquired information is “Yes” indicating that the tone packet is waiting to be received (YES in S207), the process proceeds to S208, and if “No” indicating that the tone packet is not being received (S207). NO), it returns to S201.

  The musical tone packet reception waiting terminal detection unit 307 displays the information registered in the field 3082 of the record 3080 searched in S207 from “Yes” indicating that it is in a reception waiting state, and “No” indicating that it is not in a reception waiting state. And the registered content of the field 3083 of this record 3080 is set to NULL.

  The multicast address change instruction unit 309 indicates that the information registered in the field 3082 of the record 3080 searched in S207 is “Yes” indicating that the information is in a reception waiting state, and “No” indicating that the information is not in a standby state. If the change is detected, a multicast address change instruction for instructing the subordinate radio telephone terminal 2 to change to the default multicast address is generated (S209).

  Then, the multicast address change instruction unit 309 generates a packet storing the multicast address change instruction generated in S209 with the address registered in the field 3081 of the record 3080 searched in S207 as a destination. Then, this packet is transmitted from the wireless LAN packet transmitting / receiving unit 302 to the wireless LAN 5 (S210).

  That is, the multicast address change instruction unit 309 passes the generated packet to the wireless LAN packet transmission / reception unit 302. In response to this, the wireless LAN packet transmitting / receiving unit 302 controls the beacon transmitting unit 303 to transmit a beacon including a TIM. Thereafter, when a PS-POLL signal is received from the wireless telephone terminal 2 specified by the destination address of the generated packet, the generated packet is wirelessly transmitted.

  Next, if a multicast address change completion notification packet is received from the wireless telephone terminal 2 that is the destination of the packet (“YES” in S211), terminal information is transmitted on the wired network (S212), and the process returns to S201.

  FIG. 9 is a flowchart for explaining the downlink relay operation of the wireless LAN access point 3.

  When the wired LAN packet transmitting / receiving unit 301 receives a packet from the wired LAN 4 (“YES” in S221), the wired LAN packet transmitting / receiving unit 301 passes the received packet to the downlink relay unit 305. In response to this, the downlink relay unit 305 refers to the destination address and type information stored in the header of the packet received from the wired LAN packet transmission / reception unit 301, and checks whether this packet is a tone packet. (S222).

  If the packet received from the wired LAN packet transmitting / receiving unit 301 is not a musical tone packet (“NO” in S222), relay processing is performed and this packet is transmitted to the wireless LAN 5 (S223).

  That is, the downlink relay unit 305 passes this packet to the wireless LAN packet transmission / reception unit 302. In response to this, when the packet is a multicast packet, the wireless LAN packet transmission / reception unit 302 controls the beacon transmission unit 303 to transmit a beacon including DTIM, and then wirelessly transmits the multicast packet. In addition, when this packet is a unicast packet, the wireless LAN packet transmission / reception unit 302 transmits a beacon including a TIM. Thereafter, when a PS-POLL signal is received from the wireless telephone terminal 2 specified by the destination address of the generated packet, the unicast packet is wirelessly transmitted.

  On the other hand, when the packet received from the wired LAN packet transmitting / receiving unit 301 is a musical tone packet (“YES” in S222), the downlink relay unit 305 refers to the terminal state storage unit 308 and uses the same type of musical tone packet as the musical tone packet. It is checked whether or not there is a wireless telephone terminal 2 waiting to receive (S224). Specifically, the terminal status storage unit 308 is searched for a record 3080 in which the type of musical tone packet received from the wired LAN packet transmitting / receiving unit 301 is registered in the field 3083.

  When there is no wireless telephone terminal 2 waiting to receive the same type of musical tone packet as the musical tone packet received from the wired LAN packet transmitting / receiving unit 301 (“NO” in S224), the downstream relay unit 305 relays the musical tone packet. It discards without (S225).

  On the other hand, when there is a wireless telephone terminal 2 that is waiting to receive the same type of musical tone packet as the musical tone packet received from the wired LAN packet transmitting / receiving unit 301 (“YES” in S224), the downlink relay unit 305 A multicast address associated with the type and registered in the multicast address storage unit 306 is specified (S226). Then, the downlink relay unit 305 changes the destination address of this musical sound packet to the specified multicast address (S227). Thereafter, relay processing is performed, and this musical tone packet is transmitted to the wireless LAN 5 (S228).

  That is, the downlink relay unit 305 passes this musical sound packet to the wireless LAN packet transmission / reception unit 302. In response to this, the wireless LAN packet transmitting / receiving unit 302 controls the beacon transmitting unit 303 to transmit a beacon including DTIM. Thereafter, this musical sound packet is transmitted wirelessly.

  FIG. 10 is a flowchart for explaining the operation when the wireless telephone terminal 2 belongs to the wireless LAN access point 3.

  When the wireless telephone terminal 2 belongs (S231), the wireless LAN access point 3 refers to the terminal state storage unit 308 and determines whether there is terminal information of another wireless LAN access point 3 (S232). When there is no belonging terminal information (“NO” in S232), the wireless LAN access point adds information on the wireless telephone terminal belonging to the terminal state storage unit (S233), and executes the multicast address change instruction shown in FIG. S234).

  If there is belonging terminal information (“YES” in S232), it is determined whether a musical sound packet is being requested (S235). If the musical sound packet is being requested (“YES” in S235), the wireless LAN access point downlink relay operation shown in FIG. 9 is executed (S237).

  If no musical tone packet is being requested (“NO” in S235), the stored terminal state storage unit is updated (S236), and the multicast address change instruction shown in FIG. 8 is executed.

  Next, an operation example of the radiotelephone system according to the present embodiment will be described.

  FIG. 11 is a sequence diagram showing a packet flow when a call arrives at the radio telephone terminal 2, and shows a packet flow before and after the radio telephone terminal 2 is handed over.

  When the INVITE packet is transmitted from the main apparatus 1 to the wireless telephone terminal 2 via the wireless LAN access point 3-1 (S <b> 301, S <b> 302), the wireless LAN access point 3-1 waits for reception of a tone packet storing the ring tone. A state start event “INVITE packet reception” is detected (S303). Then, a multicast address change instruction for instructing the change to the multicast address “AAA.BBB.CCC.EEE” associated with the musical tone packet type “ringtone” is generated (S304), and the packet storing this instruction is stored. Is transmitted to the wireless telephone terminal 2 that is the destination of the INVITE packet (S305). Receiving this, the radio telephone terminal 2 changes the multicast address of the received multicast packet to the multicast address “AAA.BBB.CCC.EEE” designated by the multicast address change instruction (S306).

  Next, the wireless LAN access point 3-1 generates a terminal information notification packet (S307), and transmits the packet storing the terminal information to the wireless LAN access point 3-2 (S308). Receiving this, the wireless LAN access point 3-2 stores the terminal information under the control of the wireless LAN access point 3-1 (S309).

  Next, a 180 Ringing packet is transmitted from the wireless telephone terminal 2 to the main apparatus 1 via the wireless LAN access point 3-1 (S310, S311). In response to this, the main apparatus 1 transmits a tone packet storing the ringtone. (S312 and S313). When the wireless LAN access point 3-1 receives this musical tone packet, the destination address (multicast address) of this musical tone packet is set to the multicast address “AAA.BBB. CCC.EEE "(S314). Then, this musical sound packet is wirelessly transmitted (S315). In the wireless telephone terminal 2 that is the destination of the INVITE packet, the received multicast address is changed to “AAA.BBB.CCC.EEE”. For this reason, it is possible to reliably receive a musical sound packet storing a ringtone, which is wirelessly transmitted from the wireless LAN access point 3. The wireless LAN access point 3-2 that has received the musical tone packet transmitted from the main apparatus 1 discards the musical tone packet when the subordinate radio telephone terminal 2 does not request the musical tone packet (S316).

  When the wireless telephone terminal 2 switches the belonging from the wireless LAN access point 3-1 to the wireless LAN access point 3-2 according to the wireless LAN handover procedure (S317, S318), the wireless LAN access point 3-2 Refers to the terminal information stored in S309 (S319).

  The main device 1 continues to transmit the musical tone packet storing the ring tone (S320, S321), but the wireless LAN access point 3-1 no longer has the wireless telephone terminal 2 that requires the musical tone packet. The musical tone packet is discarded (S324). On the other hand, when the wireless LAN access point 3-2 to which the wireless telephone terminal 2 that requires the musical tone packet belongs receives this musical tone packet, the destination address (multicast address) of the musical tone packet is changed to the type “ The multicast address “AAA.BBB.CCC.EEE” associated with “ring tone” is changed (S322). Then, this musical sound packet is wirelessly transmitted (S323).

  Next, when a 200 OK (off-hook) packet is transmitted from the wireless telephone terminal 2 to the main apparatus 1 via the wireless LAN access point 3-2 (S325, S326), the wireless LAN access point 3-2 stores the ring tone. A reception stop state “200 OK (off-hook) packet transmission” of the received musical sound packet is detected (S327). Then, a multicast address change instruction for instructing updating to the multicast address set to the initial value is generated (S328), and the packet storing this instruction is transmitted to the radio telephone terminal 2 that is the transmission source of the 200 OK (off-hook) packet. (S329). Receiving this, the radio telephone terminal 2 updates the multicast address of the received multicast packet to the initial multicast address designated by the multicast address change instruction (S330).

  The wireless LAN access point 3-2 instructed to update to the initial value generates a terminal state notification packet (S331), transmits the terminal state notification to the wired network, and the wireless telephone terminal 2 does not need this musical tone packet. It is notified (S332). Receiving the notification, the wireless LAN access point 3-1 updates the terminal information storage unit (S333).

  12 and 13 are sequence diagrams showing the flow of packets when the radiotelephone terminal 2 makes a call, and show the flow of packets before and after the radiotelephone terminal 2 is handed over.

  As shown in FIG. 12, when the INVITE packet is transmitted from the wireless telephone terminal 2 to the main apparatus 1 via the wireless LAN access point 3 (S351, S352), the wireless LAN access point 3 transmits the musical sound packet storing DT. A reception wait state start event “INVITE packet transmission” is detected (S353). Then, a multicast address change instruction for instructing change to the multicast address “AAA.BBB.CCC.HHH” associated with the musical sound packet type “DT” is generated (S354), and a packet storing this instruction is generated. Then, it transmits to the wireless telephone terminal 2 that is the transmission source of the INVITE packet (S355).

  Receiving this, the radio telephone terminal 2 changes the multicast address of the received multicast packet to the multicast address “AAA.BBB.CCC.HHH” designated by the multicast address change instruction (S356).

  Next, the wireless LAN access point 3-1 generates a terminal information notification packet (S357), and transmits the packet storing the terminal information to the wireless LAN access point 3-2 (S358). Receiving this, the wireless LAN access point 3-2 stores the terminal information under the control of the wireless LAN access point 3-1 (S359).

  Next, a 100 Trying packet is transmitted from the main apparatus 1 to the radio telephone terminal 2 via the wireless LAN access point 3-1 (S360, S361), and then the main apparatus 1 transmits a musical sound packet storing DT (S362, S361). S363). When the wireless LAN access point 3-1 receives this musical tone packet, the multicast address “AAA.BBB.CCC” that associates the destination address (multicast address) of this musical tone packet with the type “DT” of this musical tone packet. .HHH ”(S364). Then, this musical sound packet is wirelessly transmitted (S365). In the wireless telephone terminal 2 that is the source of the INVITE packet, the multicast address to be received is changed to “AAA.BBB.CCC.HHH”. For this reason, it is possible to reliably receive a musical sound packet storing DT wirelessly transmitted from the wireless LAN access point 3-1. The wireless LAN access point 3-2 that has received the musical tone packet transmitted from the main apparatus 1 discards the musical tone packet when the subordinate radio telephone terminal 2 does not request the musical tone packet (S366).

  When the wireless telephone terminal 2 switches the belonging from the wireless LAN access point 3-1 to the wireless LAN access point 3-2 according to the wireless LAN handover procedure (S367, S368), the wireless LAN access point 3-2 Refers to the terminal information stored in S359 (S369).

  The main device 1 continues to transmit the musical tone packet storing the ring tone (S370, S371), but the wireless LAN access point 3-1 no longer has a wireless telephone terminal 2 that requires the musical tone packet. The musical tone packet is discarded (S372). On the other hand, when the wireless LAN access point 3-2 belonging to the wireless telephone terminal 2 that requires this musical tone packet receives this musical tone packet, the destination address (multicast address) of this musical tone packet is changed to the type “ The multicast address “AAA.BBB.CCC.HHH” associated with “DT” is changed (S373). Then, this musical sound packet is wirelessly transmitted (S374).

  Next, when the dial information packet is transmitted from the wireless telephone terminal 2 to the main apparatus 1 via the wireless LAN access point 3-2 (S375, S376), the wireless LAN access point 3-2 stores the musical sound packet storing DT. The reception waiting state stop event “dial information packet transmission” is detected (S377). Then, a multicast address change instruction for setting the initial value and instructing the update to the multicast address is generated (S378), and the packet storing this instruction is transmitted to the wireless telephone terminal 2 that is the transmission source of the dial information packet (S379). ). Receiving this, the wireless telephone terminal 2 updates the multicast address of the received multicast packet to the initial multicast address designated by the multicast address change instruction (S380).

  The wireless LAN access point 3-2 instructed to update to the initial value generates a terminal state notification packet (S381), transmits the terminal state notification to the wired network, and the wireless telephone terminal 2 does not need this musical tone packet. It is notified (S382). Receiving the notification, the wireless LAN access point 3-1 updates the terminal information storage unit (S383).

  Next, as shown in FIG. 13, when the 180 Ringing packet is transmitted from the main apparatus 1 to the wireless telephone terminal 2 via the wireless LAN access point 3 (S401, S402), the wireless LAN access point 3 stores the RBT. A music packet reception wait state start event “180 Ringing packet reception” is detected (S403). Then, a multicast address change instruction for instructing the change to the multicast address “AAA.BBB.CCC.FFF” associated with the musical sound packet type “RBT” is generated (S404), and the packet storing this instruction is stored. , 180Ringing packet is transmitted to the wireless telephone terminal 2 that is the destination (S405). Receiving this, the radio telephone terminal 2 changes the multicast address of the received multicast packet to the multicast address “AAA.BBB.CCC, EEE” designated by the multicast address change instruction (S406).

  Next, the wireless LAN access point 3-1 generates a terminal information notification packet (S407), and transmits the packet storing the terminal information to the wireless LAN access point 3-2 (S408). Receiving this, the wireless LAN access point 3-2 stores the terminal information under the control of the wireless LAN access point 3-1 (S409).

  Next, the main device 1 transmits a musical sound packet storing the RBT (S410, S411). When the wireless LAN access point 3-1 receives this musical tone packet, the multicast address “AAA.BBB.CCC” that associates the destination address (multicast address) of this musical tone packet with the type “RBT” of this musical tone packet. .EEE "(S412). Then, this musical sound packet is wirelessly transmitted (S413). In the radio telephone terminal 2 that is the destination of the 180 Ringing packet, the multicast address to be received is changed to “AAA.BBB.CCC.FFF”. For this reason, it is possible to reliably receive the musical tone packet storing the RBT transmitted wirelessly from the wireless LAN access point 3-1. The wireless LAN access point 3-2 that has received the musical tone packet transmitted from the main device 1 discards the musical tone packet when the subordinate radio telephone terminal 2 does not request the musical tone packet (S414).

  When the wireless telephone terminal 2 switches the belonging from the wireless LAN access point 3-1 to the wireless LAN access point 3-2 according to the wireless LAN handover procedure (S415, S416), the wireless LAN access point 3-2 Refers to the terminal information stored in S359 (S417).

  The main device 1 continues to transmit the musical tone packet storing the ring tone (S418, S419), but the wireless LAN access point 3-1 no longer has the wireless telephone terminal 2 that requires the musical tone packet under its control. The musical tone packet is discarded (S420). On the other hand, when the wireless LAN access point 3-2 belonging to the wireless telephone terminal 2 that requires this musical tone packet receives this musical tone packet, the destination address (multicast address) of this musical tone packet is changed to the type “ The multicast address “AAA.BBB.CCC.EEE” associated with “RBT” is changed (S421). Then, this musical sound packet is wirelessly transmitted (S422).

  Next, when the 200 OK packet is transmitted from the main apparatus 1 to the wireless telephone terminal 2 via the wireless LAN access point 3-2 (S423, S424), the wireless LAN access point 3 waits to receive a musical sound packet storing the RBT. The state stop event “200 OK packet received” is detected (S425). Then, a multicast address change instruction for instructing update to the multicast address set to the initial value is generated (S426), and the packet storing this instruction is transmitted to the radio telephone terminal 2 that is the destination of the 200 OK packet (S427). . Receiving this, the radio telephone terminal 2 updates the multicast address of the received multicast packet to the initial multicast address designated by the multicast address change instruction (S428).

  The wireless LAN access point 3-2 instructed to update to the initial value generates a terminal state notification packet (S429), transmits the terminal state notification to the wired network, and the wireless telephone terminal 2 makes this musical tone packet unnecessary. It is notified (S430). Receiving the notification, the wireless LAN access point 3-1 updates the terminal information storage unit (S431).

  FIG. 14 is a sequence diagram showing a packet flow when the call partner of the radio telephone terminal 2 disconnects the call, and shows a packet flow before and after the radio telephone terminal 2 is handed over.

  When the BYE packet is transmitted from the main apparatus 1 to the wireless telephone terminal 2 via the wireless LAN access point 3-1 (S <b> 451, S <b> 452), the wireless LAN access point 3-1 is waiting to receive a musical sound packet storing BT. The start event “BYE packet reception” is detected (S453). Then, a multicast address change instruction for instructing change to the multicast address “AAA.BBB.CCC.GGG” associated with the musical sound packet type “BT” is generated (S454), and the packet storing this instruction is generated. The BYE packet is transmitted to the wireless telephone terminal 2 that is the destination (S455). Receiving this, the radio telephone terminal 2 changes the multicast address of the received multicast packet to the multicast address “AAA.BBB.CCC.GGG” designated by the multicast address change instruction (S456).

  Next, the wireless LAN access point 3-1 generates a terminal information notification packet (S457), and transmits the packet storing the terminal information to the wireless LAN access point 3-2 (S458). Receiving this, the wireless LAN access point 3-2 stores the terminal information under the control of the wireless LAN access point 3-1 (S459).

  Next, the main device 1 transmits a musical sound packet storing BT (S460, 461). When the wireless LAN access point 3-1 receives this musical tone packet, the multicast address “AAA.BBB.CCC” that associates the destination address (multicast address) of this musical tone packet with the type “BT” of this musical tone packet. .GGG "(S462). Then, this musical sound packet is wirelessly transmitted (S463). In the wireless telephone terminal 2 that is the destination of the BYE packet, the multicast address to be received is changed to “AAA.BBB.CCC.GGG”. For this reason, it is possible to reliably receive a musical tone packet storing BT transmitted wirelessly from the wireless LAN access point 3. The wireless LAN access point 3-2 that has received the musical tone packet transmitted from the main apparatus 1 discards the musical tone packet when the subordinate radio telephone terminal 2 does not request the musical tone packet (S464).

  When the wireless telephone terminal 2 switches the belonging from the wireless LAN access point 3-1 to the wireless LAN access point 3-2 according to the wireless LAN handover procedure (S465, S466), the wireless LAN access point 3-2 Refers to the terminal information stored in S359 (S467).

  The main device 1 continues to transmit the musical tone packet storing the ring tone (S468, S469), but the wireless LAN access point 3-1 no longer has a wireless telephone terminal 2 that requires the musical tone packet. The musical tone packet is discarded (S470). On the other hand, when the wireless LAN access point 3-2 belonging to the wireless telephone terminal 2 that requires this musical tone packet receives this musical tone packet, the destination address (multicast address) of this musical tone packet is changed to the type “ The multicast address “AAA.BBB.CCC.GGG” associated with “BT” is changed (S471). Then, this musical sound packet is wirelessly transmitted (S472).

  Next, when the 200 OK packet is transmitted from the wireless telephone terminal 2 to the main apparatus 1 via the wireless LAN access point 3-2 (S473, S474), the wireless LAN access point 3-2 transmits the musical sound packet storing the BT. A reception wait state stop event “200 OK packet transmission” is detected (S475). Then, a multicast address change instruction for instructing updating to the multicast address set to the initial value is generated (S476), and the packet storing this instruction is transmitted to the radio telephone terminal 2 that is the transmission source of the 200 OK packet (S477). ). Receiving this, the radio telephone terminal 2 updates the multicast address of the received multicast packet to the initial multicast address designated by the multicast address change instruction (S478).

  The wireless LAN access point 3-2 instructing the update to the initial value generates a terminal state notification packet (S479), transmits the terminal state notification to the wired network, and the wireless telephone terminal 2 does not need this musical tone packet. It is notified (S480). Receiving the notification, the wireless LAN access point 3-1 updates the terminal information storage unit (S481).

  FIG. 15 is a sequence diagram showing a packet flow when the radiotelephone terminal 2 holds the call, and shows a packet flow before and after the radiotelephone terminal 2 is handed over.

  When the hold notification packet is transmitted from the wireless telephone terminal 2 to the main apparatus 1 via the wireless LAN access point 3-1 (S 501 and S 502), the wireless LAN access point 3-1 receives the music packet storing the hold sound. The waiting state start event “hold notification packet transmission” is detected (S503). Then, a multicast address change instruction for instructing the change to the multicast address “AAA.BBB.CCC.DDD” associated with the musical sound packet type “hold tone” is generated (S504), and the packet storing this instruction is stored. Is transmitted to the wireless telephone terminal 2 that is the transmission source of the hold tone request packet (S505). Receiving this, the radio telephone terminal 2 changes the multicast address of the received multicast packet to the multicast address “AAA.BBB.CCC.DDD” designated by the multicast address change instruction (S506).

  Next, the wireless LAN access point 3-1 generates a terminal information notification packet (S507), and transmits the packet storing the terminal information to the wireless LAN access point 3-2 (S508). Receiving this, the wireless LAN access point 3-2 stores the terminal information under the control of the wireless LAN access point 3-1 (S509).

  Next, the main device 1 transmits a musical sound packet storing a holding sound (S510, S511). When the wireless LAN access point 3-1 receives this musical tone packet, the destination address (multicast address) of this musical tone packet is assigned to the multicast address “AAA.BBB. CCC.DDD "(S512). Then, this musical sound packet is wirelessly transmitted (S513). In the wireless telephone terminal 2 that is the transmission source of the music on hold request packet, the multicast address to be received is changed to “AAA.BBB.CCC.DDD”. For this reason, it is possible to reliably receive a musical sound packet stored on hold and transmitted wirelessly from the wireless LAN access point 3. The wireless LAN access point 3-2 that has received the musical tone packet transmitted from the main apparatus 1 discards the musical tone packet when the subordinate radio telephone terminal 2 does not request the musical tone packet (S514).

  When the wireless telephone terminal 2 switches the belonging from the wireless LAN access point 3-1 to the wireless LAN access point 3-2 according to the wireless LAN handover procedure (S 515, S 516), the wireless LAN access point 3-2 Refers to the terminal information stored in S509 (S517).

  The main device 1 continues to transmit the musical tone packet storing the ringtone (S518, S519), but the wireless LAN access point 3-1 no longer has the wireless telephone terminal 2 that requires the musical tone packet under its control. The musical tone packet is discarded (S520). On the other hand, when the wireless LAN access point 3-2 belonging to the wireless telephone terminal 2 that requires this musical tone packet receives this musical tone packet, the destination address (multicast address) of this musical tone packet is changed to the type “ The multicast address "AAA.BBB.CCC.DDD" associated with "holding tone" is changed (S521). Then, this musical sound packet is wirelessly transmitted (S522).

  Next, when the hold release packet is transmitted from the main apparatus 1 to the wireless telephone terminal 2 via the wireless LAN access point 3 (S523, S524), the wireless LAN access point 3 waits for reception of a music packet storing the hold sound. A state stop event “receive hold release packet” is detected (S525). Then, a multicast address change instruction for instructing the change to the multicast address set to the initial value is generated (S526), and the packet storing this instruction is transmitted to the radio telephone terminal 2 that is the destination of the music-on-hold release packet ( S527). In response to this, the radio telephone terminal 2 returns the multicast address of the received multicast packet to the initial multicast address designated by the multicast address change instruction (S528).

  The wireless LAN access point 3-2 instructed to update to the initial value generates a terminal state notification packet (S529), transmits the terminal state notification to the wired network, and the wireless telephone terminal 2 does not need this musical tone packet. It is notified (S530). Receiving the notification, the wireless LAN access point 3-1 updates the terminal information storage unit (S531).

  The embodiment of the present invention has been described above.

  In the present embodiment, the wireless LAN access point 3 associates the multicast address of the wireless telephone terminal 2 that is waiting to receive a musical sound packet with the type of musical sound packet that the wireless telephone terminal 2 is waiting to receive. Change to a predetermined multicast address. Further, the multicast address of the musical tone packet received from the main device 1 is changed to a predetermined multicast address associated with the type of the multicast packet, and then wirelessly transmitted. For this reason, according to the present embodiment, the musical tone packet received from the main apparatus 1 can be received only by the radio telephone terminal 2 that is in a reception waiting state for the same type of musical tone packet as the musical tone packet. Thereby, the duration of the awake state in the radio telephone terminal 2 in the power saving mode can be shortened, and battery consumption of the radio telephone terminal 2 can be reduced. Furthermore, when a wireless terminal moves between wireless access points while receiving a multicast packet, the reception of the multicast packet can be continued without delay.

  Further, in the present embodiment, the wireless LAN access point 3 sets the multicast address of the wireless telephone terminal 2 to the initial state when the wireless telephone terminal 2 that is waiting for the reception of the musical sound packet has finished the reception waiting state. Return to the multicast address set in the value. For this reason, according to the present embodiment, it is possible to reliably cause the radio telephone terminal 2 that is not in a reception state of a musical tone packet to receive a multicast packet other than the musical tone packet.

  Further, in the present embodiment, the wireless LAN access point 3 determines whether or not the wireless telephone terminal 2 is waiting to receive a musical sound packet based on a call control packet that the wireless telephone terminal 2 sends and receives with the main device 1. , And when the wireless telephone terminal 2 is waiting to receive a musical sound packet, the type of musical sound packet that the wireless telephone terminal 2 is waiting to receive is detected. For this reason, according to the present embodiment, the wireless LAN access point 3 is in a state of waiting for receiving a musical tone packet at the wireless LAN access point 3 without sending and receiving a special message between the wireless telephone terminal 2 and the wireless LAN access point 3. Can be monitored.

  Further, in the present embodiment, the wireless LAN access point 3 is configured such that the wireless telephone terminal 2 that is waiting to receive the same type of musical tone packet as the musical tone packet received from the main device 1 does not exist in the wireless LAN 5 (own jurisdiction area). If this is the case, the musical tone packet is discarded. For this reason, according to the present embodiment, it is possible to prevent unnecessary musical sound packets from being transmitted to the wireless LAN 5, thereby reducing communication traffic of the wireless LAN 5.

  In addition, this invention is not limited to said embodiment, Many deformation | transformation are possible within the range of the summary. For example, the configuration of the wireless telephone terminal 2 and the wireless LAN access point 3 may be implemented by an integrated logic IC such as ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), or DSP. (Digital Signal Processor) or the like may be executed by software by a computer.

  In the above embodiment, the wireless LAN access point 3 determines whether or not the wireless telephone terminal 2 is waiting to receive a musical sound packet based on a call control packet that the wireless telephone terminal 2 sends and receives with the main device 1. When the wireless telephone terminal 2 is in a musical tone packet reception waiting state, the type of the musical sound packet that the wireless telephone terminal 2 is waiting to receive is detected. However, the present invention is not limited to this. When the wireless telephone terminal 2 is in a standby state for receiving a musical tone packet, it notifies the wireless LAN access point 3 together with the type of the musical tone packet, and when it is no longer in a standby state for receiving a musical tone packet, this fact is indicated. May be notified to the wireless LAN access point 3.

  In the above embodiment, a musical tone packet has been described as an example of a multicast packet for changing a multicast address. However, the present invention is not limited to this. The same applies to multicast packets other than musical tone packets.

  In the above embodiment, the case where the wireless telephone terminal 2 is used as a wireless terminal has been described as an example. However, the present invention is not limited to this. The present invention can also be applied to a wireless terminal such as a PDA.

FIG. 1 is a schematic configuration diagram of a radiotelephone system to which an embodiment of the present invention is applied. FIG. 2 is a schematic functional block diagram of the radio telephone terminal 2. FIG. 3 is a diagram for explaining an operation flow of the radio telephone terminal 2 in the power saving mode. FIG. 4 is a schematic diagram of the wireless LAN access point 3. FIG. 5 is a diagram schematically illustrating an example of registered contents in the multicast address storage unit 306. FIG. 6 is a diagram schematically showing a determination table used for detecting the reception state of a musical tone packet and detecting the type of musical tone packet waiting to be received. FIG. 7 is a diagram schematically illustrating an example of registered contents in the terminal state storage unit 308. FIG. 8 is a flowchart for explaining the multicast address change instruction operation of the wireless LAN access point 3. FIG. 9 is a flowchart for explaining the downlink relay operation of the wireless LAN access point 3. FIG. 10 is a flowchart for explaining a case where the wireless telephone terminal 2 belongs to the wireless LAN access point 3. FIG. 11 is a sequence diagram showing a packet flow when a call arrives at the wireless telephone terminal 2. FIG. 12 is a sequence diagram showing the flow of packets when the wireless telephone terminal 2 makes a call. FIG. 13 is a sequence diagram showing a packet flow when the wireless telephone terminal 2 makes a call. FIG. 14 is a sequence diagram showing a packet flow when the call partner of the wireless telephone terminal 2 disconnects the call. FIG. 15 is a sequence diagram showing the flow of packets when the radiotelephone terminal 2 holds a call.

Explanation of symbols

  1: main device, 2: wireless telephone terminal, 3: wireless LAN access point, 4: wired LAN, 5: wireless LAN, 201: wireless LAN packet transmitting / receiving unit, 202: beacon receiving unit, 203: MM interface unit, 204: Operation mode control unit 205: Operation mode setting unit 206: Communication protocol processing unit 207: Multicast address changing unit 301: Wired LAN packet transmitting / receiving unit 302: Wireless LAN packet transmitting / receiving unit 303: Beacon transmitting unit 304: Uplink relay unit, 305: Downlink relay unit, 306: Multicast address storage unit, 307: Music packet reception waiting terminal detection unit, 308: Terminal state storage unit, 309: Multicast address change instruction unit, 310: Terminal information detection unit, 311 : Terminal information transmitter

Claims (3)

The continuously line access point you relay packetized data comprises multicast packets with the wireless terminal connected to the main device and the wireless network connected to the wired network,
An address storing means for storing in association with the type and the multicast address of the multicast packet of the multicast packet,
If the local radio access point contains the call control information to the data to be relayed, the reception waiting end end detecting means for detecting a radio terminal waiting for reception of a particular type of multicast packet from the call control information ,
An address change instruction means for instructing to change the multicast address corresponding to the specific type of the multicast address stored in said address storage means of the wireless terminal to the wireless terminal the reception waiting end end detecting means detects,
The particular when receiving the multicast packet according to the type, the received multicast packet before Symbol radio terminal to change the multicast address of the multicast address indicated by the multicast address change instruction means for transmitting from the previous SL main unit to the wireless terminal A multicast address change transmission means for transmitting to
The type of the multicast packet stored in the address storage means, the multicast address for transmitting the multicast packet, and the address of the wireless terminal waiting to receive the multicast packet detected by the reception waiting terminal detecting means are used as access point information , and other wireless An access point information notification means for notifying the access point ;
Upon receiving access point information from another wireless access point, other access point information storage means for storing the access point information ;
Terminal information setting means for executing, when the wireless terminal related to the access point information belongs to the own wireless access point, the multicast address change transmitting means from the stored access point information; Wireless access point with transfer function.
The wireless access point according to claim 1 ,
The access point information notification means includes
The address of the wireless terminal in standby state for receiving multicast packets detected by the reception waiting end end detecting means, the pre-Symbol type of multicast packets of the wireless terminal is waiting for reception via the wired network to another wireless access point A wireless access point having a terminal information transfer function characterized by notifying.
A wireless access point according to claim 1 or 2 ,
If the wireless terminal has performed handover, before referring to the access point information that remembers the Kia access point information storage unit, a wireless terminal that is stored before Kia access point information storage means If there is, a wireless access point having a terminal information transfer function, characterized in that it starts sending multicast packets.

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