JP2008160711A - Communications system and communication control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To locally stabilize voice quality in an IP telephone system, and the like. <P>SOLUTION: A communication system has a means for receiving information on quality deterioration for informing prescribed quality deterioration state which is detected by monitoring packets related to speech communication from a communication control device which detects the prescribed quality deterioration state and a control means for performing the process of restraining generation of new calls, when the information on quality deterioration is received. By using such a communications system, increase in network load is suppressed, and the voice quality can be locally stabilized. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a communication control method, and more particularly to a technique for stabilizing voice quality locally in an IP (Internet Protocol) telephone system or the like.

  In an IP telephone system in an IP network, a change in the state of the network is larger than that in a conventional circuit-switched telephone system, and the change affects voice quality. However, since such a network state change is not a device failure, the standard monitoring function of the devices that make up the IP telephone system takes action to determine where the problem occurs even if the sound quality deteriorates. It is difficult to determine whether it should be. In particular, when a wireless LAN (Local Area Network), which has recently become widespread, is used on the terminal device side of the network, the variation in sound quality is larger than that of a wired LAN. A specific quality fluctuation factor of a wireless LAN is a device that generates interference in other nearby wireless LAN systems and radio waves in a nearby frequency band in addition to quality fluctuation caused by temporary traffic increase, which is a problem common to IP networks. There are many elements that are difficult to predict such as

  When using the IP telephone system in such a wireless LAN environment, it is useful for the user to know whether the environment in the wireless zone is suitable for a call before making a call. However, under the present circumstances, the user actually gets a phone call and experiences the phenomenon that the voice quality is poor or not connected to know the state of the network. Moreover, if such a method is tried by a user, it will lead to the occurrence of collisions in the wireless LAN section and increased traffic as an IP network, which will further deteriorate the network state.

For example, Japanese Patent Application Laid-Open No. 2006-121166 discloses a technique for improving voice quality by solving a shortage of network bandwidth when it is detected that voice quality of an IP phone has deteriorated. Specifically, a voice quality control system for maintaining voice quality of a call on a network using a packet communication protocol, a call control device for establishing and disconnecting a call between terminals connected to the network, Voice quality evaluation means for evaluating the voice quality of the call on the network, and an instruction to reduce the bandwidth used for the voice packet including the voice data of the call when the voice quality is lower than the predetermined voice quality (for example, voice Instruction to change codec used for data, instruction to change transmission interval of voice packet including voice data, instruction to restrict newly generated call to call control means, instruction to disconnect established call to call control means A voice quality control system including a bandwidth control device. However, the call control device and the bandwidth control device of the voice quality control system are premised on a configuration in which one is provided in the IP telephone system, and the quality evaluation means is also intended for a fairly wide range such as the Tokyo area and the Kansai area. . In other words, it does not consider the problem of extremely small areas such as part of the office. Further, it is assumed that a general telephone is used, and the terminal does not perform an operation for stabilizing the voice quality. Furthermore, the quality evaluation means performs measurement using pseudo voice packets, and has a problem of increasing network traffic.
JP 2006-121166 A

  In the conventional technology as described above, since voice quality is handled in a large-scale system, it is not possible to meticulously deal with deterioration of voice quality in a very small area such as a part of an office. In addition, it is not preferable to send a pseudo voice packet to measure voice quality in a situation where congestion occurs. Further, the terminal device is premised on having no function, but this does not solve the above-described problem such as a collision and an increase in network load.

  Accordingly, an object of the present invention is to provide a technique for stabilizing voice quality locally in an IP telephone system or the like.

  Another object of the present invention is to provide a technique for notifying a user of quality deterioration information in an IP telephone system or the like.

  The communication device according to the first aspect of the present invention provides quality degradation information for notifying a predetermined quality degradation state detected by monitoring a packet related to a call, and communication in which the predetermined quality degradation state is detected. Means for receiving from the control device and management means for executing processing for suppressing the occurrence of a new call when quality degradation information is received.

  By using such a communication device, an increase in network load can be suppressed and voice quality can be stabilized locally.

  Note that the predetermined quality degradation state described above may be a quality degradation state for a packet transmitted from a communication terminal under the control of the communication control apparatus. This is particularly effective in suppressing an increase in network load caused by communication terminals.

  Further, the process for suppressing the generation of a new call notifies the user of a process for forcibly prohibiting the generation of a new call (for example, an incoming call and a call, or a call), a call impossible, or quality degradation. It may be a process (for example, display or audio output). In this way, it is possible to avoid giving the user an unpleasant experience.

  Furthermore, the process for suppressing the occurrence of a new call may be a process for prohibiting relaying of a packet related to a call from a call terminal under the communication control device. If the communication device is a relay device, the network load can be suppressed by prohibiting the relay of packets related to outgoing calls. Note that relay of a packet related to a call to a call terminal may be prohibited.

  In the communication control method according to the second aspect of the present invention, the quality control information for notifying the predetermined quality deterioration state detected by monitoring a packet related to a call is used as the communication control method for detecting the predetermined quality deterioration state. A step of receiving from the apparatus, and a management step of executing a process for suppressing the occurrence of a new call when quality degradation information is received. The first aspect of the present invention is also applicable to the second aspect.

  A program for causing a processor to execute the method according to the present invention can be created, and the program is stored in a storage medium or storage device such as a flexible disk, a CD-ROM, a magneto-optical disk, a semiconductor memory, and a hard disk. Is done. In some cases, digital signals are distributed over a network. Note that data being processed is temporarily stored in a storage device such as a computer memory.

  According to the present invention, voice quality can be stabilized locally in an IP telephone system or the like.

  In addition, according to another aspect of the present invention, it is possible to notify quality degradation information to a user in an IP telephone system or the like.

  FIG. 1 shows a system outline diagram according to an embodiment of the present invention. For example, a VoIP (Voice over IP) server SV1 and switches SW1 and SW2 are connected to the IP network NW. The VoIP server SV1 is a SIP (Session Initiation Protocol) server, for example, and performs major processing in the IP telephone system, but is not described further because it is hardly related to the processing according to the present embodiment. The functions of the switches SW1 and SW2 are almost the same as those of ordinary switches. However, the switch SW1 is connected to the VoIP probe VP1 that performs the main processing in the present embodiment, and the switch SW2 is connected to the VoIP probe VP2. Therefore, the switches SW1 and SW2 are packets that pass through other ports. Have a mirror port or tap that outputs the same packet.

  A wireless LAN access point WLAP1 is connected to the switch SW1. An example in which one wireless LAN access point WLAP1 is connected to the switch SW1 is shown in FIG. 1, but the number is not limited to one. Similarly, a wireless LAN access point WLAP2 is connected to the switch SW2. The same applies to the number of wireless LAN access points WLAP2.

  For example, wireless IP telephones WT1 to WT4 are wirelessly connected to the wireless LAN access point WLAP1. The wireless IP phones WT1 to WT4 constitute a group WTG1. The number of wireless IP telephones connected to one wireless LAN access point WLAP is not limited to four. The wireless LAN access points WLAP1 and 2 also have a configuration unique to this embodiment. The group WTG1 is managed as a wireless IP phone under the control of the VoIP probe VP1.

  Similarly, wireless IP telephones WT6 to WT10 are wirelessly connected to the wireless LAN access point WLAP2. The wireless IP phones WT6 to WT10 constitute a group WTG11. The wireless IP telephones WT1 to WT10 also have a configuration unique to this embodiment. The group WTG11 is managed as a wireless IP phone under the control of the VoIP probe VP2.

  Hereinafter, the VoIP probe VP1 will be mainly described. As shown in FIG. 2, the packet transmission direction Q addressed to the access network A including the group WTG1 and the wireless LAN access point WLAP1, and other access networks (for example, B to D) connected from the access network A to the IP network NW. Or the packet transmission direction P addressed to any one of them), and in this embodiment, this direction is distinguished and processing is performed.

  Further, the voice accommodating packet passing through the IP network NW is, for example, a packet as shown in FIG. That is, the voice accommodating packet includes a transmission source address, a destination address, a protocol-dependent header, a transmission port number, a reception port number, protocol-dependent information, and voice information. For more details, it follows RFC 1889 of IETF (Internet Engineering Task Force). In addition, the packet for voice communication includes a SIP signaling packet (for example, a call request INVITE).

  Next, a functional block diagram of the VoIP probe VP1 is shown in FIG. The VoIP probe VP1 includes a monitoring network interface 11 connected to the voice communication network via a mirror port or a tap of the switch SW1, and a packet quality inspection unit 12 connected to the monitoring network interface 11 and performing packet quality inspection. A deterioration threshold storage unit 13 for storing a deterioration threshold used for quality inspection of the packet quality inspection unit 12, a log storage unit 15 for storing inspection results (degradation information) of the packet quality inspection unit 12, and the log storage unit 15 Used by the degradation communication state management unit 14 that manages the quality information, the quality information generation unit 16 that generates and outputs the quality degradation information or the quality restoration information based on the instruction from the packet quality inspection unit 12, and the quality information generation unit 16 A transmission group setting storage unit 17 for storing data related to the transmission destination group; And a control network interface 19 to be output to the monitor control network quality deterioration information or quality recovery information from the quality information generating unit 16. The supervisory control network is a network for notifying the subordinate IP phones WT1 to WT4 of quality deterioration information or quality restoration information. For example, the supervisory control network is not a physical network but a network in an address band different from the voice communication network. These functions are realized by a combination of software and hardware. The transmission group setting storage unit 17 stores address band data for each group of IP telephones under its control (for example, corresponding to the access network of FIG. 2).

  The packet quality inspection unit 12 has a degradation state (that is, packet loss, delay jitter, delay, etc.) exceeding the threshold value stored in the degradation threshold value storage unit 13 at an evaluation time interval that is extremely short as compared with a general telephone call time. ) Is evaluated.

  The log storage unit 15 stores degradation state data detected by the packet quality inspection unit 12. For example, the data is as shown in FIG. In the example of FIG. 5, the time of occurrence, source address, destination address, degradation state, valid flag, outgoing telephone number, incoming telephone number, etc. are stored as one record. The valid flag is set to ON only for the latest record among records representing the same state, and is set to OFF for other states. As will be described below, the state A is determined to be different if the source address band is different.

  When the deterioration communication state management unit 14 does not receive deterioration information indicating the same deterioration state from the packet quality inspection unit 12 for a predetermined time or more, the deterioration communication state management unit 14 determines that the deterioration state is restored and notifies the packet quality inspection unit 12 of the recovery. When the packet quality inspection unit 12 receives data about the deteriorated state determined to be recovered from the deteriorated communication state management unit 14, the packet quality inspection unit 12 causes the quality information generating unit 16 to generate quality recovery information about the deteriorated state.

  An example of the packet structure of quality degradation information or quality recovery information is shown in FIG. In the example of FIG. 6, the source address (the address of the VoIP probe VP1), the destination address, the protocol-dependent header, the quality state, the detection direction reception address (P direction in FIG. 2), and the detection direction transmission address (FIG. 2 Q direction) and the detection time. In the following description, as the quality state, a code representing the occurrence of the state B representing the quality degradation state for the own access network, a code representing the occurrence of the state A representing the quality degradation state for the other access network, and the state A code indicating recovery from A and a code indicating recovery from state B are included. An example in which no level exists in each state will be described, but a level corresponding to the degree of deterioration may be set. For example, each time deterioration progresses, levels such as state A1, state A2, and state A3, and levels such as state B1, state B2, and state B3 may be set.

  FIG. 7 shows a functional block diagram of the IP telephones WT1 to WT10. The IP telephones WT1 to WT10 include a signal bus 21, a control bus 28, a voice processing unit 23 for processing voice accommodating packets, a network interface 22 connected to the wireless LAN access point WLAP, and data to be notified to the user. A display / I / O unit 24 that outputs a message, a call control unit 25 that controls incoming and outgoing calls, a quality management unit 26 that manages voice quality in the present embodiment, and controls the entire IP telephone. And a control unit 27. A network interface 22, an audio processing unit 23, and a display / I / O unit 24 are connected to the signal bus 21. A network interface 22, a voice processing unit 23, a display / I / O unit 24, a call control unit 25, a quality management unit 26, and a control unit 27 are connected to the control bus 28. The audio processing unit 23 includes a reception buffer 231 for audio accommodation packets and a signal processing unit 232 that performs audio signal processing on audio information in the audio accommodation packets.

  The quality management unit 26 manages data as shown in FIG. 8, for example. In the example of FIG. 8, the status, the transmission source, the time, and the reception buffer size are stored. The VoIP probe VP may be notified of quality degradation information indicating the same state many times. However, the quality management unit 26 has a record indicating the same state in the data managed by the VoIP probe VP. The “time” data is updated with the detection time. However, an effective flag may be provided and stored every time quality degradation information is received. Only the valid flag of the latest record may be turned on. The reception buffer size is set only in the state A, but if there is a level division for the state A, an initial reception buffer size is set according to the level.

  FIG. 9 shows a functional block diagram of the wireless LAN access points WLAP1 and 2. The wireless LAN access points WLAP 1 and 2 include a signal bus 31, a control bus 35, a first network interface 32 on the wireless LAN side, a relay processing unit 33, a second network interface 34 on the switch SW side, and a subordinate IP A terminal management unit 36 that manages the telephone, a quality management unit 37 that performs processing on quality degradation information and quality restoration information, and a control unit 38 that controls the entire wireless LAN access point WLAP. The quality management unit 37 holds the data shown in FIG.

  Next, processing contents of the VoIP probe VP1 will be described with reference to FIGS. First, the packet quality inspection unit 12 of the VoIP probe VP1 monitors various monitoring parameters such as delay jitter, packet loss, and delay for the packet received via the monitoring network interface 11 (FIG. 10: step S1). And it is judged whether each monitoring parameter exceeded the threshold value compared with the various threshold values stored in the deterioration threshold value storage part 13 (step S2). If there is no monitoring parameter exceeding the threshold, the process returns to step S1. On the other hand, if there is a monitoring parameter that exceeds the threshold, the source address, destination address, detection time (occurrence time), and the like of the packet that exceeds the threshold are specified and output to the deteriorated communication state management unit 14. Then, the deteriorated communication state management unit 14 receives the transmission source address, the destination address, the detection time, etc., and stores them in the log storage unit 15 (step S5). If the calling telephone number and the incoming telephone number can be specified, they are stored in the same manner. At this stage, the deterioration state is not yet specified, and the valid flag is set to ON.

  Such a process is performed until an instruction to end such as turning off the power is given (step S7). The detection process of the packet quality inspection unit 12 is repeatedly performed according to the received packet separately from other processes.

  Next, processing for data stored in the log storage unit 15 will be described with reference to FIG. The deteriorated communication state management unit 14 specifies a processing period (a period from a specific start time to a specific end time) for determining whether or not a plurality of records are recorded for packets addressed to the same destination address group ( Step S8). For example, if the predetermined interval is 5 seconds, the period from 9:00:00 to 9:00:05 is specified as the processing period. Then, the record within the specified processing period is scanned (step S9), and it is determined whether there are records for a plurality of communications within the processing period (step S10). Rather than specifying a case where there are a plurality of records for only the same combination of the transmission source address and the destination address, it is determined whether there are records for different combinations of the transmission source address and the destination address.

  If records exist only for the same combination of the source address and the destination address, the process proceeds to step S17. On the other hand, when there are records for different combinations of the source address and the destination address, the deteriorated communication state management unit 14 determines whether the destination address groups match (step S11). That is, it is determined whether the destination address of the corresponding record is within a predetermined address range. More specifically, it is determined whether the destination address of the corresponding record falls within the address group under the VoIP probe VP1. If the destination address groups match, the process proceeds to step S17.

  When the destination address groups of the corresponding records match or when there are no records for a plurality of communications within the processing period, the deteriorated communication state management unit 14 receives the packet from another access network instead of a packet transmitted from the subordinate of the VoIP probe VP1. State A indicating that a problem has occurred in this packet is registered in the corresponding record within the processing period (step S17). Then, the corresponding records are grouped by the transmission source address, and the validity flag of the record other than the last record in the group is set to OFF (step S19). For example, the corresponding records are grouped for each access network under the control of the VoIP probe VP1 based on the transmission source address, and only the last record in the group is left valid. If the valid flag is ON for records of the same source address group in the same state A before the processing period, it is changed to OFF.

  Then, the deteriorated communication state management unit 14 outputs a quality deterioration information generation instruction including a record in which the valid flag is ON in the state A to the packet quality inspection unit 12. The packet quality inspection unit 12 outputs a quality deterioration information generation instruction including the received record to the quality information generation unit 16. The quality information generation unit 16 receives the quality degradation information generation instruction from the packet quality inspection unit 12, and the source address of the record whose validity flag is ON during the processing period or the source address including the source address Quality degradation information designating the group and state A is generated (step S21). 6 includes a code indicating the occurrence of the state A as the quality state in the packet format, and the detection direction transmission address is the transmission source address of the record in which the valid flag is ON during the processing period or the transmission source address. Contains source address group data to be included. The detection direction reception address may include the data of the destination address or destination address group of the record, or may be empty. The detection time includes the occurrence time of the record.

  Thereafter, the quality information generation unit 16 transmits the generated quality deterioration information to a destination address group including the destination address of the record or a terminal under the VoIP probe VP1 (step S23). Then, control goes to a step S25.

  If it is determined in step S11 that the destination address groups of the corresponding records do not match, the deteriorated communication state management unit 14 indicates that a problem has occurred in the packet transmitted from the subordinate of the VoIP probe VP1, that is, the VoIP probe VP1. State B indicating that congestion has occurred in any of the subordinate access networks is registered in the corresponding record within the processing period (step S12).

  Further, the deteriorated communication state management unit 14 groups the corresponding records by the transmission source address, and sets the validity flag of the record other than the last record in the group to OFF (step S13). For example, the corresponding records are grouped for each access network under the control of the VoIP probe VP1 based on the transmission source address, and only the last record in the group is left valid. If the valid flag is ON for records in the same source address group in state B before the processing period, the records are changed to OFF.

  Then, the deteriorated communication state management unit 14 outputs information on the record in which the valid flag is ON in the state B to the packet quality inspection unit 12. The packet quality inspection unit 12 outputs a quality deterioration information generation instruction including the received record to the quality information generation unit 16. The quality information generation unit 16 receives a quality deterioration information generation instruction from the packet quality inspection unit 12, and generates quality deterioration information specifying the state B (step S14). 6 includes a code indicating the occurrence of the state B as the quality state in the packet format, and the detection direction transmission address is the transmission source address of the record whose validity flag is ON during the processing period or the transmission source address. The included source address group data may be included, or may be empty. The detection direction reception address may include the data of the destination address or destination address group of the record, or may be empty. The detection time includes the occurrence time of the record.

  Thereafter, the quality information generation unit 16 searches the transmission group setting storage unit 17 with the transmission source address of the record in which the validity flag is ON in the state B, and identifies the access network and the wireless LAN access point of the quality deterioration information. The quality degradation information specified as the transmission destination and generated is transmitted to the specified transmission destination (step S15).

  For example, the deteriorated communication state management unit 14 determines whether or not the process should be terminated (step S25). If the process is not terminated, the next processing period is specified (step S27) and the process returns to step S9. On the other hand, if the process should be terminated, the process is terminated.

  By performing such processing, a problem has occurred in another access network, and a problem has occurred in the state A to be handled for packets from the other access network and the access network under the VoIP probe VP1. Therefore, it is distinguished from the state B that should deal with the subordinate access network, and is notified to the IP telephone of the subordinate access network (IP telephone and wireless LAN access point for the state B). In steps S13 and S19, the validity flag is managed so that the validity period can be confirmed.

  Next, restoration processing in the VoIP probe VP1 will be described with reference to FIG. The deteriorated communication state management unit 14 scans the record in the log storage unit 15 (step S31). Then, it is determined whether or not there is a record whose valid flag is ON after a predetermined time or more (step S33). If there is no record whose valid flag is ON after a predetermined time has elapsed, the process returns to step S31.

  On the other hand, when there is a record for which the valid flag has been turned ON for a predetermined time or longer, the deteriorated communication state management unit 14 sends a quality recovery information generation instruction including the data of the detected record to the packet quality inspection unit 12. Output. The packet quality inspection unit 12 receives the quality recovery information generation instruction including the data of the detection record from the deteriorated communication state management unit 14 and further outputs it to the quality information generation unit 16. The quality information generation unit 16 receives a quality recovery information generation instruction including the data of the detection record from the packet quality inspection unit 12, and generates quality recovery information using the data of the detection record (step S35). In the packet format of FIG. 6, a code indicating recovery of the state A or the state B of the detection record is included as the quality state. Further, the detection direction transmission address includes data of a transmission source address in the detection record or a transmission source address group including the transmission source address. If it is in state A, it is used in an IP telephone or the like. Further, the detection direction reception address may include the data of the destination address or destination address group of the detection record, or may be empty. The detection time includes the generation time of the detection record.

  Furthermore, the quality information generation unit 16 specifies the transmission destination from the data of the detection record, and transmits the quality recovery information (step S37). In the case of state A, the transmission destination is a destination address group including the destination address of the detection record or a terminal under the VoIP probe VP1, as in step S23. In the case of state B, the transmission destination is the same as in step S15. Then, the transmission group setting storage unit 17 is searched with the transmission source address of the detection record, and the access network and its wireless LAN access point are found.

  Further, the deteriorated communication state management unit 14 sets the valid flag of the detection record to OFF (step S39).

  Then, the deteriorated communication state management unit 14 determines whether or not to end the process (step S41), and returns to step S31 if the process is not ended. If the process should be terminated, the process is terminated.

  As described above, if the same problem does not occur even after the elapse of a predetermined time, which is the effective period, that is, if the effective flag is left on, the quality recovery is notified.

  Next, the operation of the IP telephone WT1 will be described with reference to FIG. IP phone WT 1 receives the packet via network interface 22. When a packet in the packet format as shown in FIG. 6 is received, it is output to the quality management unit 26 via the control bus 28. The quality management unit 26 determines whether or not the quality deterioration information (packet including the code of occurrence of the state A or the state B) of the packet format shown in FIG. 6 has been received (FIG. 13: Step S51). If no quality deterioration information has been received, the process returns to step S51. On the other hand, when the quality deterioration information is received, the network deterioration state is set based on the state included in the quality deterioration information (step S53). In the table as shown in FIG. 8, if the state is A, the state A and the transmission source are registered. If the state is B, the state B is registered. In the case of state B, if it has already been set before step S53, it is not necessary to register again. In the state A, if the source address or the source address group is different, a new record is registered. If records with the same source address or source address group have already been registered, there is no need to register again.

  Further, the quality management unit 26 registers the time corresponding to the set state or the like (step S55). When a new network degradation state is set, the received detection time is registered as it is, and when a registered state exists, the registered time is updated with the received detection time.

  And it is judged whether the state of the received quality degradation information is the state A (step S57). If the status is A, the quality management unit 26 sets the reception buffer size corresponding to the transmission source address or the transmission source address group in the received quality degradation information (step S59). Here, the source address group and the reception buffer size are set in the audio processing unit 23 as well as being registered in the table of FIG. The reception buffer size is set to a size larger than the normal size (for example, S1 in FIG. 8). However, step S59 is skipped in the case of registration. If there is a level division in state A, the reception size may be reset according to the level division. Then, control goes to a step S63.

  On the other hand, in the state B, the quality management unit 26 causes the call control unit 25 and / or the display / I / O unit 24 to start the call setting suppression operation (step S61). In the case of the call control unit 25, an operation for rejecting new calls and incoming calls (for example, an operation for rejecting transmission / reception of INVITE in SIP), or an operation for rejecting only new calls (for example, transmission of INVITE in SIP) Action to refuse). In the case of the display / I / O unit 24, when a message such as “Currently unusable” or “Current sound quality is not good” is displayed on the display unit of the IP telephone WT1, or when the receiver is raised, To output a message such as In this way, it is possible to prevent unnecessary “try-out” by the user and further congest the network. Thereafter, the process proceeds to step S63.

  For example, the quality management unit 26 determines whether the process should be terminated (step S63). If the process should not be terminated, the process returns to step S51. On the other hand, if the process should be terminated, the process is terminated.

  By performing such processing, IP phone WT1 can start the call setting suppression operation for state B, and can set the reception buffer size corresponding to the source address group and the like for state A. become. Moreover, it becomes possible to confirm the expiration date of the state by performing step S55.

  Next, incoming call processing will be described with reference to FIG. In the state A, even when an incoming call is suppressed, the processing flow shown in FIG. 14 is not performed. In other cases, the call control unit 25 establishes a session with another IP telephone and performs voice communication. When receiving the accommodation packet, the voice processing unit 23 performs the following processing.

  That is, the voice processing unit 23 determines whether the incoming call is from the set source address group (step S71). If the incoming call is not from the set source address group, the process proceeds to step S75. On the other hand, if the incoming call is from the set transmission source address group, the voice processing unit 23 expands the initial size of the reception buffer 231 according to the reception buffer size set corresponding to the transmission source address group ( Step S73). As a result, more voice accommodating packets than usual can be accumulated from the beginning of the call, and the signal processing unit 232 can perform voice signal processing.

  If it is determined in step S71 that the incoming call is not received after step S73 or from the set source address group, the voice processing unit 23 adaptively changes the reception buffer size according to the communication state. A size adaptation process is performed (step S75). Since this process is a process that is usually performed, it will not be described further. Then, the voice processing unit 23 determines whether or not the call has ended (step S77). If the call has not ended, the process proceeds to step S75. On the other hand, if the call is terminated, the process is terminated. Note that the reception buffer size is initialized.

  If such processing is performed, even when a call is received from another network with a poor network state, voice processing can be performed without delay since the voice processing can be performed in response to delay and delay jitter from the start of the call. Thus, the user's uncomfortable feeling can be alleviated. If the size of the reception buffer is always increased, the user feels uncomfortable, so the reception buffer is not enlarged except for the corresponding incoming call.

  Next, the state release processing of IP telephone WT1 will be described using FIG. The quality management unit 26 determines whether the quality restoration information is received from the VoIP probe VP1 via the network interface 22 (step S81). When the quality restoration information is received, the corresponding state is changed to the normal state based on the quality restoration information (step S83). That is, the record corresponding to the state B or state A and the source address or source address group included in the quality recovery information is deleted. Then, control goes to a step S91.

  On the other hand, when the quality restoration information has not been received, the quality management unit 26 determines whether there is a state in which a predetermined time has elapsed (step S87). If the same quality deterioration information is not received for a predetermined time or longer, the time is not updated in step S55, so that it can be determined that the quality deterioration state has been recovered without receiving the quality recovery information. Therefore, if there is a state in which a predetermined time has elapsed, the corresponding state is changed to a normal state (step S89). That is, the record for the corresponding state is deleted.

  And it is judged whether the state changed into the normal state was the state A (step S91). When the state is not the state A but the state B, the call control suppressing operation is stopped in the call control unit 25, the display / I / O unit 24, or both (step S93). Then, control goes to a step S97. On the other hand, if the state is state A, the voice processing unit 23 is caused to clear the transmission source address group and the reception buffer size related to state B changed to the normal state (step S95). Thus, even if there is an incoming call from the source address group, the signal processing unit 232 starts processing with a normal reception buffer size.

  Then, the quality management unit 26 determines whether or not to end the process (step S97), and returns to step S81 when the process should not be ended. On the other hand, if the process should be terminated, the process is terminated.

  By performing such processing, it becomes possible to deal with quality recovery information from the VoIP probe VP1 and to change the state to the normal state by itself.

  Next, processing of the wireless LAN access point WLAP1 will be described with reference to FIG. The wireless LAN access point WLAP1 does not process the voice accommodation packet, so only the state B is handled.

  The wireless LAN access point WLAP1 receives the packet via the second network interface 34. When a packet in the packet format as shown in FIG. 6 is received, it is output to the quality management unit 37 via the control bus 35. The quality management unit 37 determines whether or not the quality deterioration information (packet including the code of occurrence of the state A or the state B) of the packet format shown in FIG. 6 has been received (FIG. 13: Step S51). If no quality deterioration information has been received, the process returns to step S51. On the other hand, when the quality deterioration information is received, the network deterioration state is set based on the state included in the quality deterioration information (step S53). Unlike IP phone WT1, only state B is notified or only state B can be dealt with, so state B is registered. If it has already been set before step S53, it is not necessary to register again.

  Moreover, the quality management part 37 registers time corresponding to the set state etc. (step S55). When a new network degradation state is set, the received detection time is registered as it is, and when a registered state exists, the registered time is updated with the received detection time.

  And since state A does not respond | correspond, it does not transfer to Yes route of step S57.

  Proceeding with the No route in Step S57, the quality management unit 37 causes the relay processing unit 33 to start a call setting suppression operation (Step S61). That is, the relay of the packet related to the incoming call to the subordinate IP telephones WT1 to WT4 managed by the terminal management unit 36 and the packet related to the outgoing call from the IP telephones WT1 to WT4 (for example, the INVITE packet in SIP) is stopped. Let It may be possible not to relay only packets related to calls from subordinate IP phones WT1 to WT4.

  For example, the quality management unit 37 determines whether the process should be terminated (step S63). If the process should not be terminated, the process returns to step S51. On the other hand, if the process should be terminated, the process is terminated.

  By carrying out such processing, the wireless LAN access point WLAP1, which is a relay device, can quickly resolve congestion in its own access network, and voice quality can be restored early. Become. Note that when the IP telephone performs the processing of FIGS. 13 to 15 described above, the wireless LAN access point WLAP1 does not need to perform the processing described above. However, if all the IP telephones under the wireless LAN access point WLAP1 cannot perform the processes as shown in FIGS. 13 to 15, the wireless LAN access point WLAP1 only performs the processes described above. There is.

  Next, the state cancellation processing of the wireless LAN access point WLAP1 will be described with reference to FIG. The quality management unit 37 determines whether or not quality restoration information has been received from the VoIP probe VP1 via the second network interface 34 (step S81). When the quality restoration information is received, the corresponding state is changed to the normal state based on the quality restoration information (step S83). That is, the record corresponding to the state B included in the quality recovery information is deleted. Then, control goes to a step S91.

  On the other hand, if the quality restoration information has not been received, the quality management unit 37 determines whether there is a state in which a predetermined time or more has elapsed (step S87). If the same quality deterioration information is not received for a predetermined time or longer, the time is not updated in step S55, so that it can be determined that the quality deterioration state has been recovered without receiving the quality recovery information. Accordingly, when there is a state in which a predetermined time has elapsed, the state is changed to a normal state. That is, the record for the corresponding state is deleted.

  As described above, since the wireless LAN access point WLAP1 does not become the state A, the No route of step S91 is advanced, and the relay processing unit 33 stops the call setting suppression operation (step S93). Thereafter, the process proceeds to step S97.

  Then, the quality management unit 37 determines whether or not to end the process (step S97), and returns to step S81 when the process should not be ended. On the other hand, if the process should be terminated, the process is terminated.

  By performing such processing, it becomes possible to deal with quality recovery information from the VoIP probe VP1 and to change the state to the normal state by itself.

  Although one embodiment of the present invention has been described above, the present invention is not limited to this. For example, the functional blocks shown in FIG. 4, FIG. 7, and FIG. 9 are examples, and a module according to such a functional configuration does not necessarily exist.

  Further, the processing flow described above is an example, and another processing flow that performs the same function may be adopted.

  In addition, the IP telephone may be configured to support only the state A, or may be configured to support only the state B.

It is a system outline figure in an embodiment of the invention. It is a figure for demonstrating the network outline | summary in embodiment of this invention. It is a figure which shows an example of the packet format of the packet for audio | voice communication. It is a functional block diagram of a VoIP probe. It is a figure which shows an example of the data stored in a log storage part. It is a figure which shows an example of the packet format of quality degradation information or quality restoration information. It is a functional block diagram of an IP telephone. It is a figure which shows an example of the data managed by the quality management part of an IP telephone. It is a functional block diagram of a wireless LAN access point. It is a figure which shows the main processing flow of a VoIP probe. It is a figure which shows the processing flow of the process with respect to the data stored in the log storage part. It is a figure which shows the processing flow of the recovery process of a VoIP probe. It is a figure which shows the main processing flow of an IP telephone or a wireless LAN access point. It is a figure which shows the processing flow of the process at the time of an incoming call in an IP telephone. It is a figure which shows the processing flow of the state cancellation | release process in an IP telephone or a wireless LAN access point.

Explanation of symbols

11 Monitoring network interface 12 Packet quality inspection unit 13 Degradation threshold storage unit 14 Degraded communication state management unit 15 Log storage unit 16 Quality information generation unit 17 Transmission group setting storage unit 19 Control network interface 21, 31 Signal bus 22 Network interface 23 Voice processing unit 24 Display / I / O unit 25 Call control unit 26, 37 Quality management unit 27, 38 Control unit 28, 35 Control bus 32 First network interface 33 Relay processing unit 34 Second network interface 36 Terminal management unit

Claims (6)

Means for receiving quality deterioration information for notifying a predetermined quality deterioration state detected by monitoring a packet related to a call from a communication control device that has detected the predetermined quality deterioration state;
When the quality degradation information is received, a management means for performing processing for suppressing the occurrence of a new call;
A communication device. The communication apparatus according to claim 1, wherein the predetermined quality deterioration state is a quality deterioration state for a packet transmitted from a communication terminal subordinate to the communication control apparatus. The communication apparatus according to claim 1, wherein the process for suppressing the occurrence of a new call is a process for forcibly prohibiting the occurrence of a new call or a process for notifying a user of a call failure or quality deterioration. 2. The process for suppressing the occurrence of a new call is a process for prohibiting a call originating from a call terminal subordinate to the communication control apparatus or relaying of a packet related to a call to the call terminal. The communication device described. Receiving quality deterioration information for notifying a predetermined quality deterioration state detected by monitoring a packet related to a call from a communication control device that has detected the predetermined quality deterioration state;
When receiving the quality degradation information, a management step for performing processing for suppressing the occurrence of a new call;
Including a communication control method.   A program for causing a processor to execute the communication control method according to claim 5.

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