JP5859483B2 - Communication apparatus and program - Google Patents

Description

  The present invention relates to a communication device and a program.

Conventionally, there has been known a communication apparatus that performs communication via an NNI (Network-Network Interface). (For example, refer to Patent Document 1).
[Prior art documents]
[Patent Literature]
[Patent Document 1] JP-A-2005-292955

  However, there is a case where sufficient communication quality cannot be maintained when congestion occurs in the communication path via the NNI.

  According to the first aspect of the present invention, based on the path quality measuring unit that measures the path quality of the first communication path a plurality of times, and the plurality of path qualities of the first communication path measured by the path quality measuring unit, A communication device is provided that includes a congestion state determination unit that determines a congestion state of a first communication path.

  In the communication apparatus, the path quality measurement unit may measure a response time of communication via the first communication path with respect to another communication apparatus, and the communication apparatus has a history of response times measured by the path quality measurement unit. And an average response time calculation unit that calculates an average response time that is an average of a plurality of response times stored in the history storage unit. The congestion state of the first communication path may be determined based on the average response time calculated by the calculation unit and the response time newly measured by the path quality measurement unit. In the communication apparatus, the congestion state determination unit is a sign that congestion occurs in the first communication path when the response time newly measured by the path quality measurement unit is longer than a predetermined time with respect to the average response time. May be determined. The communication apparatus includes: a congestion state determination unit that determines whether or not a congestion state of the first communication path determined by the congestion state determination unit satisfies a predetermined criterion; and a congestion state determination unit that determines whether the first communication path When it is determined that the congestion state satisfies a predetermined standard, communication is performed via the first communication path, and it is determined that the congestion state of the first communication path does not satisfy the predetermined standard And a communication unit that communicates via the second communication path.

  In the communication apparatus, the path quality measurement unit may measure the first response time by transmitting a quality measurement packet or the like to another communication apparatus via the first communication path. Measuring the second response time of the quality measurement packet transmitted to the other communication device via the second communication path at a frequency lower than the frequency of transmitting the quality measurement packet to the other communication device via the communication path; The congestion state determination unit may determine the congestion state of the second communication path based on the second response time. In the communication apparatus, the history storage unit may store a history of the second response time, and the average response time calculation unit may calculate a second average response time that is an average of the second response times stored in the history storage unit. The congestion state determination unit may calculate the congestion of the second communication path based on the second average response time calculated by the average response time calculation unit and the second response time newly measured by the path quality measurement unit. The communication device may further include a communication unit that communicates via the first communication path or the second communication path selected based on the congestion state of the first communication path and the congestion state of the second communication path. You may prepare. In the communication apparatus, the first communication path may be a path that passes through the NNI, and the second communication path may be a path that passes through the UNI (User-Network Interface).

  According to the 2nd aspect of this invention, the program for functioning a computer as said communication apparatus is provided.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

1 schematically shows an example of a telephone system. An example of a functional structure of a terminal adapter is shown roughly. The timing of quality measurement packet transmission by the quality measurement packet transmission unit is schematically shown. An example of the processing flow by a terminal adapter is shown roughly. It is a conceptual diagram for demonstrating determination of the congestion state by the congestion state determination part. An example of the process by a terminal adapter is shown roughly. An example of the process by a terminal adapter is shown roughly. An example of a processing flow of a terminal adapter, a SIP server, and a quality measurement server is shown roughly. An example of a processing flow of a terminal adapter, a SIP server, and a quality measurement server is shown roughly.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 schematically shows an example of a telephone system 10 according to the present embodiment. The telephone system 10 provides an IP telephone service to the terminal adapter 200 and the telephone 300. The terminal adapter 200 may be an example of a communication device. The telephone system 10 includes an NGN (NEXT GENERATION NETWORK) 110, an NGN 120, a connection operator network 130, an IP telephone service network 140, and a PSTN (Public Switched Telephony Network) 150.

  The NGN 110 is connected to the connection operator network 130 via the NNI 112. The NGN 120 is connected to the connection operator network 130 via the NNI 122. When the NGNs 110 and 120 are described without distinction, they may be simply referred to as NGNs. Further, when the NNIs 112 and 122 are described without distinction, they may be simply referred to as NNIs. The connection provider network 130 is connected to the IP telephone service network 140. IP telephone service network 140 is connected to PSTN 150.

  The user of the terminal adapter 202 and the telephone 302 and the user of the terminal adapter 204 and the telephone 304 may acquire a right to use communication via the NGN 110 by making a contract with a provider that provides the NGN 110. In addition, the user of the terminal adapter 206 and the telephone 306 and the user of the terminal adapter 208 and the telephone 308 may acquire a right to use communication via the NGN 120 by making a contract with a provider that provides the NGN 120. . In addition, each user of the telephones 302, 304, 306, and 308 may acquire a right to use the IP telephone service by making a contract with a provider that provides the IP telephone service network 140.

  The IP telephone service network 140 includes a SIP server 142. The SIP server 142 holds a correspondence table between the telephone number of the telephone 300 and the IP address, and executes SIP message processing. For example, when the telephone 302 attempts to establish a call with the telephone 306, the terminal adapter 202 transmits a SIP message to the SIP server 142 via the NGN 110, the NNI 112, and the connection carrier network 130. The telephone set 302 and the telephone set 306 that have established a call through the SIP server 142 transmit and receive voice data via the NGN 110, the NNI 112, the connection provider network 130, the NNI 122, and the NGN 120.

  Further, when the telephone 302 attempts to establish a call with the fixed telephone 152 or the mobile telephone 154 connected to the PSTN 150, the terminal adapter 202 communicates with the SIP server 142 via the NGN 110, the NNI 112, and the connection carrier network 130. Send a message. The telephone 302 that has established a call through the SIP server 142 and the fixed telephone 152 or the mobile telephone 154 transmit and receive voice data via the NGN 110, the NNI 112, the connection carrier network 130, the IP telephone service network 140, and the PSTN 150. .

  As described above, the telephone 300 can implement a call via the NGNs 110 and 120, the NNIs 112 and 122, and the connection carrier network 130. However, since the NGN 110 and the NGN 120 are the best effort type, there are cases where sufficient communication quality cannot be maintained. In particular, when trying to provide a 0AB-J IP telephone service, high call quality is required, for example, the packet loss rate must be less than 0.1%, but the condition may not be satisfied.

  Therefore, the telephone system 10 according to the present embodiment is configured to perform detouring to enable detouring when the communication quality of the communication path passing through the NGNs 110 and 120, the NNIs 112 and 122, and the connection carrier network 130 is deteriorated. Provide a route. Here, a case where the telephone system 10 includes detour paths 164, 166, and 168 from the NGN 110 and detour paths 174, 176, and 178 from the NGN 120 will be described as an example. The number of detour paths is an example, and other numbers may be used. The detour paths 164, 166, 168, 174, 176, and 178 may be collectively referred to simply as a detour path.

  The detour path 164 may be configured by a UNI 114, a relay adapter 414, and a SBC (Session Border Controller) 514. The relay adapter 414 is connected to the NGN 110 via the UNI 114. The SBC 514 is connected to the relay adapter 414 IP telephone service network 140.

  The relay adapter 414 is connected to the NGN 110 when, for example, a provider that provides the IP telephone service network 140 makes a contract with a provider that provides the NGN 110. The SBC 514 and the IP telephone service network 140 are connected by, for example, Ethernet (registered trademark). The SBC 514 may be managed by a provider that provides the IP telephone service network 140. The SBC 514 implements routing via the relay adapter 414 by performing IP conversion between the IP telephone service network 140 and the network on the NGN 110 side.

  For example, the SBC 514 once terminates the packet addressed to the SIP server 142 transmitted by the terminal adapter 202 received by the relay adapter 414 via the UNI 114. The SBC 514 converts the address into an IP address between the IP telephone service network 140 and the network on the NGN 110 side, and transmits the packet to the SIP server 142. This realizes routing via the UNI 114 that is handled as the end of the IP network.

  The bypass path 166 may have the same configuration as that of the bypass path 164, and may be configured by the UNI 116, the relay adapter 416, and the SBC 516. The bypass path 168 may have the same configuration as the bypass path 164 and may be configured by the UNI 118, the relay adapter 418, and the SBC 518. In FIG. 1, the bypass route 164, the bypass route 166, and the bypass route 168 are illustrated as separate routes, but may be realized as a VLAN (Virtual LAN) on one physical route.

  The detour paths 174, 176, 178 may have the same configuration as the detour paths 164, 166, 168, respectively, UNI 124, 126, 128, relay adapters 424, 426, 428, and SBCs 524, 526, 528, respectively. May be configured.

  Note that the UNIs 114, 116, 118, 124, 126, and 128 may be simply referred to as UNI when they are described without distinction. When the relay adapters 414, 416, 418, 424, 426, and 428 are described without distinction, they may be simply referred to as relay adapters. When the SBCs 514, 516, 518, 524, 526, and 528 are described without distinction, they may be simply referred to as SBCs.

  The terminal adapter 200 measures the route quality of a route passing through the NNI (sometimes referred to as an NNI route) and a route passing through the UNI (sometimes referred to as a UNI route). The NNI path may be an example of a first communication path. The UNI path may be an example of a second communication path.

  For example, the terminal adapter 200 measures the route quality of the NNI route by transmitting a quality measurement packet to the quality measurement server 144 via the NNI route that passes through the NGN, the NNI, and the connected carrier network 130. Further, for example, the terminal adapter 200 measures the path quality of the UNI path by transmitting a quality measurement packet to the quality measurement server 144 via the UNI path passing through the NGN, UNI, and relay adapter.

  If the terminal adapter 200 determines that the route quality of the NNI route does not exceed a predetermined criterion, the terminal adapter 200 selects a UNI route that satisfies the predetermined criterion from among the UNI routes as a bypass route, and selects it. Communication is performed via the UNI path. As a result, even if congestion occurs in the NNI route and the route quality cannot satisfy the predetermined standard, communication quality that satisfies the standard can be ensured by communicating via the detour route. it can.

  FIG. 2 schematically shows an example of the functional configuration of the terminal adapter 200. The terminal adapter 200 includes a communication unit 210, a route quality measurement unit 218, a history storage unit 220, an average time calculation unit 222, a congestion state determination unit 224, and a route quality determination unit 226. The communication unit 210 includes an off-hook detection unit 212, a quality measurement packet transmission unit 214, a response reception unit 216, a route selection unit 228, a calling unit 230, an incoming call unit 232, a call unit 234, and a route registration unit 236.

  Off-hook detection unit 212 detects an off-hook of telephone 300. The quality measurement packet transmission unit 214 may transmit a quality measurement packet in response to detection of off-hook. The quality measurement packet transmission unit 214 may transmit the quality measurement packet to the quality measurement server 144 via each of the NNI route and the UNI route in response to detection of off-hook. At this time, the quality measurement packet transmission unit 214 may transmit the quality measurement packet to one UNI path among the plurality of UNI paths, or may transmit the quality measurement packet to the plurality of UNI paths.

  Further, the quality measurement packet transmission unit 214 may transmit the quality measurement packet when the telephone 300 is in a standby state. The quality measurement packet transmission unit 214 may transmit the quality measurement packet to the quality measurement server 144 via the selected communication path when the telephone 300 is in a standby state. That is, the quality measurement packet transmission unit 214 may transmit the quality measurement packet to the quality measurement server 144 via the NNI path when the NNI path is selected, and if the UNI path is selected, the quality measurement packet transmission unit 214 transmits the UNI path. The quality measurement packet may be transmitted to the quality measurement server 144 via the network.

  In this case, the quality measurement packet transmission unit 214 may periodically transmit the quality measurement packet. For example, the quality measurement packet transmission unit 214 transmits a quality measurement packet every second. Here, a case where the quality measurement packet transmission unit 214 transmits a quality measurement packet to the quality measurement server 144 will be mainly described as an example, but the present invention is not limited thereto, and the quality measurement packet transmission unit 214 If the path quality of the NNI path and the UNI path can be measured, the quality measurement packet may be transmitted to another communication apparatus. The response receiving unit 216 receives a response from the quality measurement server 144.

  The route quality measuring unit 218 measures the route quality based on the response received by the response receiving unit 216. The route quality measurement unit 218 may measure a delay time from when the quality measurement packet transmission unit 214 transmits the quality measurement packet until the response reception unit 216 receives the response. The delay time may be an example of a response time. The route quality measurement unit 218 may measure the route quality based on the delay time. The route quality measurement unit 218 may measure the packet loss rate of the quality measurement packet transmitted by the quality measurement packet transmission unit 214. Then, the route quality measurement unit 218 may measure the route quality based on the packet loss rate.

  The history storage unit 220 stores a history of delay times measured by the path quality measurement unit 218. The history storage unit 220 may store a history of delay times by identifying each communication path. The average time calculation unit 222 calculates an average delay time that is an average of the delay times for each communication path.

  The congestion state determination unit 224 determines the congestion state of the communication path. For example, the congestion state determination unit 224 determines the congestion state of the communication route based on the route quality measured by the route quality measurement unit 218. The congestion state determination unit 224 may determine whether or not congestion is likely to occur for each communication path. For example, the congestion state determination unit 224 determines that congestion is likely to occur when the measured packet loss rate exceeds a predetermined threshold. Also, for example, the congestion state determination unit 224 determines the congestion state of the communication path based on the average delay time calculated by the average time calculation unit 222 and the delay time newly measured by the path quality measurement unit 218. .

  The route quality determination unit 226 determines whether the route quality measured by the route quality measurement unit 218 exceeds a predetermined reference. For example, the route quality determination unit 226 determines whether or not the packet loss rate exceeds 0.1%. Further, the route quality determination unit 226 determines whether or not the congestion state determined by the congestion state determination unit 224 satisfies a predetermined criterion.

  The route selection unit 228 selects a communication route based on the determination result by the route quality determination unit 226. For example, the route selection unit 228 selects the NNI route as the communication route when the route quality determination unit 226 determines that the route quality of the NNI route exceeds a predetermined reference. Further, for example, the route selection unit 228 determines that the route quality determination unit 226 determines that the route quality of the NNI route does not exceed a predetermined reference, and the route quality of the UNI route exceeds the predetermined reference. If it is determined that the communication path is determined, the UNI path is selected as the communication path.

  The calling unit 230 executes a calling process according to a calling instruction from the user. The calling unit 230 may transmit the SIP message to the SIP server 142 via the communication path selected by the path selection unit 228. The incoming call unit 232 executes incoming call processing. For example, the incoming call unit 232 receives the INVEITE message from the SIP server 142 and executes the calling process. The call unit 234 establishes a call in response to the calling process by the calling unit 230 or the incoming call process by the incoming call unit 232.

  While the call by the call unit 234 is being executed, the route quality measurement unit 218 may measure the route quality of the communication route based on the call data. The route quality measurement unit 218 measures the route quality of the communication route by using, for example, RTCP-XR (RTP Control Protocol Extended Reports). Measurement of route quality based on call data may be referred to as actual call measurement.

  The route registration unit 236 registers the communication route with the SIP server 142. The route registration unit 236 may register the communication route by transmitting a REGISTER message to the SIP server 142. For example, when the path quality of the NNI path measured while the telephone 300 is in the standby state does not exceed a predetermined standard, the path registration unit 236 uses the UNI circuit that exceeds the standard as a communication path to the SIP server. 142. Thereby, when the terminal adapter 200 receives an incoming call, it is possible to bypass the NNI route whose route quality does not satisfy the standard and to select a UNI circuit that satisfies the standard.

  FIG. 3 schematically shows the timing of quality measurement packet transmission by the quality measurement packet transmission unit 214. In FIG. 3, the horizontal axis represents the passage of time. In the vertical axis direction, the telephone call state of the telephone 300, the state of the quality measurement packet transmitted by the quality measurement packet transmission unit 214, and the state of actual call measurement by the path quality measurement unit 218 are arranged in order from the top. .

  While the telephone 300 is in the standby state, the quality measurement packet transmission unit 214 periodically transmits the quality measurement packet to the quality measurement server 144. The quality measurement packet transmission unit 214 may transmit the quality measurement packet to the quality measurement server 144 via the selected communication path while the telephone 300 is in a standby state.

  In response to detecting the off-hook of the telephone 300, the quality measurement packet transmission unit 214 transmits the quality measurement packet to the quality measurement server 144. The quality measurement packet transmission unit 214 may transmit the quality measurement packet to the NNI path and the plurality of UNI paths. The quality measurement packet transmission unit 214 does not transmit a quality measurement packet during an outgoing call and an incoming call. During an outgoing call and an incoming call, the path quality measurement unit 218 performs actual call measurement.

  FIG. 4 schematically shows an example of a processing flow by the terminal adapter 200. The processing flow shown in FIG. 4 may be started when the terminal adapter 200 and the telephone 300 are turned on and the terminal adapter 200 and the telephone 300 are in a standby state.

  In step 402 (step may be abbreviated as S), the quality measurement packet transmission unit 214 transmits the quality measurement packet to the quality measurement server 144. When the NNI route is selected, the quality measurement packet transmission unit 214 transmits the PIN to the quality measurement server 144 via the NNI route. The quality measurement packet transmission unit 214 transmits the quality measurement packet to the quality measurement server 144 via each of the selected UNI path and NNI path when the UNI path is selected, that is, when the detour is being performed. You can do it.

  In S404, the route quality measurement unit 218 measures the route quality. The route quality measurement unit 218 may measure the route quality of the NNI route when the detour is not being performed. The route quality measurement unit 218 may measure the route quality of the UNI route and the NNI route when the detour is being performed.

  When the detour is not being performed (S406: NO), the route quality determination unit 226 determines whether the route quality of the NNI route measured in S404 exceeds a predetermined reference (S408). When the route quality of the NNI route does not exceed a predetermined standard (S408: NO), the route selection unit 228 selects a bypass route, and the route registration unit 236 registers the bypass route (S410). The route selection unit 228 may select one of the plurality of UNI routes as a bypass route. In this case, the route selection unit 228 may select a UNI route whose route quality exceeds a predetermined criterion from among a plurality of UNI routes. If the route quality of the NNI route exceeds a predetermined standard (S408: YES), the communication route remains the NNI route.

  When detouring is in progress (S406: YES), the route quality determination unit 226 determines whether or not the route quality of the NNI route measured in S404 exceeds a predetermined reference (S412). When the route quality of the NNI route does not exceed the predetermined standard (S412: NO), the process proceeds to S408, where the route quality determination unit 226 determines that the route quality of the currently selected UNI route exceeds the predetermined standard. It is determined whether or not.

  When the route quality of the NNI route exceeds a predetermined standard (S412: YES), the route registration unit 236 executes a failback process. That is, the path registration unit 236 registers an NNI path as a communication path instead of the UNI path. Thereby, when the route quality of the NNI route is recovered after detouring, the selected communication route can be quickly returned to the NNI route.

  Subsequently, when the incoming call unit 232 receives an incoming call (S416: YES), the process proceeds to S426, and when the incoming call is not received (S416: NO), the process proceeds to S418. In S418, when the off-hook detection unit 212 detects an off-hook of the telephone 300 (S418: YES), the process proceeds to S420. In S420, the quality measurement packet transmission unit 214 transmits the quality measurement packet to the quality measurement server 144 via each of the NNI path and the plurality of UNI paths.

  In S422, the route quality measurement unit 218 measures the route quality of each of the NNI route and the plurality of UNI routes. In S424, the route selection unit 228 selects a communication route for transmitting the SIP message. The route selection unit 228 selects the NNI route when the route quality of the NNI route exceeds a predetermined reference. When the route quality of the NNI route does not exceed a predetermined reference, the route selection unit 228 selects a UNI route that exceeds the reference. The route selection unit 228 may execute error processing so as not to make a call when there is no NNI route or UNI route that exceeds the reference. Even when there is no NNI route and UNI route that exceed the standard, if the call is an emergency call, call processing via the NNI route may be executed.

  If the incoming call unit 232 receives an incoming call in S416, the process proceeds to S426. If the call is terminated in S426 (S426: YES), the process proceeds to S428. If on-hook is performed in S428, the process proceeds to S430. In S434, when the standby state by the terminal adapter 200 is canceled due to power-off of the terminal adapter 200 or the like, the process ends. Otherwise, the process returns to S402. As described above, by measuring the route quality of the NNI route and the UNI route at the time of outgoing call, it is possible to select the appropriate communication route and execute the calling process. In addition, when the telephone 300 is in a standby state, the selected communication path is monitored, and when the path quality falls below a predetermined standard, the telephone 300 receives an incoming call by registering another path. However, an incoming call process can be executed after selecting an appropriate communication path.

  FIG. 5 is a conceptual diagram for explaining the determination of the congestion state by the congestion state determination unit 224. In the figure, the horizontal axis represents the passage of time. The vertical axis represents the delay time measured by the path quality measurement unit 218. A plurality of arrows 502 indicate the timing at which the path quality measurement unit 218 measures the delay time. The figure shows a substantially constant delay time up to n−1, and shows an example in which the delay time increases from n. When congestion occurs in the communication path, an increase in delay time as shown in the figure is seen as an indication of congestion.

  Therefore, the congestion state determination unit 224 according to the present embodiment determines that it is a sign of congestion when the amount of increase in delay time exceeds a predetermined range. The congestion state determination unit 224 may determine whether the communication path is in a congestion state indicating a sign of congestion or in a normal state, using Expression (1) and Expression (2).

ＰＤは測定された遅延時間、ＡＤは平均遅延時間、αは重み付け係数を示す。重み付け係数αは、例えば０．１〜１．０に設定される。

PD is a measured delay time, AD is an average delay time, and α is a weighting coefficient. The weighting coefficient α is set to 0.1 to 1.0, for example.

ＣＤは経路品質測定部２１８が新たに測定した遅延時間、Δは増加量閾値を示す。増加量閾値Δは、例えば１ｍｓなどの単位で設定される。増加量閾値Δは、遅延時間と輻輳状態との実験結果によってその数値が設定されてよい。

CD represents a delay time newly measured by the path quality measuring unit 218, and Δ represents an increase amount threshold value. The increase amount threshold Δ is set in units of 1 ms, for example. The increase threshold value Δ may be set to a numerical value based on the experimental results of the delay time and the congestion state.

  As described above, the congestion state determination unit 224 is based on the average delay time that is an average of a plurality of delay times stored in the history storage unit 220 and the delay time newly measured by the path quality measurement unit 218. Determine congestion status. In particular, the congestion state determination unit 224 determines that the congestion state determination unit 224 is a sign that congestion will occur when the delay time newly measured by the congestion state determination unit 224 is longer than a predetermined time with respect to the average response time.

  In the present embodiment, when the NNI route is selected and the telephone 300 is in the standby state, the quality measurement packet transmission unit 214 periodically sends the quality measurement packet to the quality measurement server 144 via the NNI route. An example in which data is transmitted is described above. At this time, the quality measurement packet transmission unit 214 may periodically transmit the quality measurement packet to the quality measurement server 144 via the UNI path. Thus, when the congestion state determination unit 224 determines the congestion state of the UNI path, a sufficient number of delay times can be secured for calculating the average delay time.

  Further, for example, when the path quality measurement unit 218 calculates the packet loss rate in units of 0.1% for a certain period of communication such as a day unit, the result of 1000 quality measurement packets is required. However, when the quality measurement packet is transmitted only through the UNI path only at the time of transmission and detouring, the number of quality measurement packets may not be sufficient. On the other hand, while the telephone 300 is in the standby state, the necessary number is obtained by collecting the results for at least several days by transmitting the quality measurement packet to the quality measurement server 144 even through the UNI path. The result of the quality measurement packet can be ensured.

  The quality measurement packet transmission unit 214 transmits the quality measurement packet to the quality measurement server 144 via the UNI path at a frequency lower than the frequency of transmitting the quality measurement packet to the quality measurement server 144 via the NNI path. Good. As a result, the processing load on the quality measurement packet transmission and the communication load applied to the communication path are reduced as compared with the case where the quality measurement packet is transmitted to the quality measurement server 144 via the NNI path at the same frequency. be able to.

  6 and 7 schematically show an example of processing by the terminal adapter 202. FIG. Here, a case will be described as an example where congestion occurs in the NNI path after the terminal adapter 202 establishes a call with the terminal adapter 204 via the NNI path.

  FIG. 6 shows a case where the NNI route is selected as the communication route. A monitoring route 192 indicates a route through which the terminal adapter 202 and the terminal adapter 204 monitor route quality. The terminal adapter 202 measures the route quality of the NNI route through the accommodation device 182, the relay router 184, and the GW router (Gateway router) 186 that the NGN 110 has. The terminal adapter 204 measures the route quality of the NNI route via the accommodation device 188, the relay router 184, and the GW router 186.

  A call path 194 indicates a call path between the terminal adapter 202 and the terminal adapter 204. The terminal adapter 202 and the terminal adapter 204 perform a call via the accommodation device 182 and the accommodation device 188. Here, as shown in the figure, the monitoring route 192 and the call path 194 do not match. Therefore, even if congestion occurs in the call path 194, the congestion cannot be found by monitoring the route quality on the monitoring route 192.

  Here, the path quality measuring unit 218 included in the terminal adapter 202 performs a call via a communication path that does not pass through the NNI and UNI, such as the call path 194, depending on data during the call, during the call or after the call ends. The path quality of the communication path may be measured. The route quality measurement unit 218 measures the route quality by using, for example, RTCP-XR. The communication path not via the NNI and the UNI may be an example of a third communication path.

  Then, the route quality determination unit 226 determines whether or not the measured route quality exceeds a predetermined reference. When it is determined that the predetermined standard is not exceeded, the path selection unit 228 selects a UNI circuit that exceeds the standard. Then, the route registration unit 236 registers the UNI route as the communication route. Thereby, for example, when the terminal adapter 202 receives an incoming call from the terminal adapter 204 after registration, the call is established not via the NNI route but via the UNI route, so that congestion can be avoided.

  FIG. 7 illustrates the monitoring route 192 and the call path 194 after the UNI route is selected by the route registration unit 236. In FIG. 7, the terminal adapter 202 transmits a quality measurement packet to the UNI path via the accommodation device 182, the relay router 184, and the accommodation device 188. In addition, the terminal adapter 204 transmits a quality measurement packet to the UNI path via the accommodation device 188. In addition, the terminal adapter 202 and the terminal adapter 204 execute a call through the UNI path. In this way, the monitoring route 192 and the call path 194 can be matched.

  FIG. 8 schematically shows an example of the processing flow of the terminal adapter 200, the SIP server 142, and the quality measurement server 144. Here, the flow of processing when congestion occurs when the terminal adapter 200 transmits a quality measurement packet to the NNI path in a state where the terminal adapter 200 registers the NNI path as a communication path in the SIP server 142 will be described.

  The route registration unit 236 transmits a REGSTER message to the SIP server 142 via the NNI route (S802). The SIP server 142 registers the NNI route as the communication route of the terminal adapter 200. The quality measurement packet transmission unit 214 transmits the quality measurement packet to the quality measurement server 144 via the NNI path (S804). Thereby, the route quality measurement unit 218 measures the NNI route control route quality. In the example shown in the figure, no congestion has occurred in the NNI path at this point.

  Next, the SIP server 142 transmits an INVITE (incoming request) message to the terminal adapter 200 (S806). Then, the terminal adapter 200 receives the INVITE (incoming request) message and transmits the INVITE (request response) message to the SIP server 142 (S808). In S810, the call starts and ends. Although not shown, in S806, the SIP server 142 transmits the INVITE (incoming request) message received from the other terminal adapter 200 to the terminal adapter 200. In step S <b> 808, the SIP server 142 transmits the INVITE (request response) message received from the terminal adapter 200 to the other terminal adapter 200. In S810, the SIP server 142 starts a call between the terminal adapter 200 and the other terminal adapter 200 and detects the end of the call.

  In S812, the route quality measurement unit 218 detects congestion of the NNI route based on the quality measurement packet transmitted by the quality measurement packet transmission unit 214 via the NNI route. The quality measurement packet transmission unit 214 transmits a quality measurement packet to the quality measurement server 144 via the UNI path in response to detecting congestion of the NNI path (S814). Here, a case where there is no congestion on the UNI path and the quality measurement packet reaches the quality measurement server 144 will be described as an example. However, if congestion occurs on the UNI path, the quality measurement packet is transmitted. The unit 214 may transmit the quality measurement packet to another UNI path.

  235 transmits a REGISTER message to the SIP server 142 to register the UNI path in response to the path quality determination unit 226 determining that the UNI path is not congested by the quality measurement packet transmitted in S814. (S816). The SIP server 142 registers the UNI path as the communication path of the terminal adapter 200 by receiving the REGISTER message.

  When the UNI path is registered as the communication path of the terminal adapter 200, the SIP server 142 transmits an INVITE (incoming request) message to the terminal adapter 200 via the UNI path (S818). The terminal adapter 200 receives the INVITE (incoming request) message and transmits an INVITE (request response) message to the SIP server 142 (S820). In S812, the call is started and the call is finished.

  Although not shown, in S818, the SIP server 142 transmits an INVITE (call request) message to the terminal adapter 200 in response to receiving an INVITE (call request) message from another terminal adapter 200. To do. In S820, the SIP server 142 transmits the INVITE (request response) message received from the terminal adapter 200 to the other terminal adapter 200. In S822, the SIP server 142 starts a call between the terminal adapter 200 and the other terminal adapter 200, and detects an end call.

  As described above, when the terminal adapter 200 detects congestion on the NNI route, if the SIP route is registered when the SIP server 142 transmits the INVITE message, the NNI route is congested. The call can be established even if the user has been in the service. Note that the quality measurement packet transmission unit 214 may transmit the quality measurement packet to the quality measurement server 144 via the selected route in response to receiving the INVITE incoming request) message.

  FIG. 9 schematically shows an example of the processing flow of the terminal adapter 200, the SIP server 142, and the quality measurement server 144. Here, a flow of processing when congestion occurs when the SIP server 142 tries to transmit an INVITE message to the terminal adapter 200 in a state where the terminal adapter 200 registers the NNI route as a communication route in the SIP server 142 will be described. To do.

  The route registration unit 236 transmits a REGISTER message to the SIP server 142 via the NNI route (S902). The SIP server 142 registers the NNI route as the communication route of the terminal adapter 200. The quality measurement packet transmission unit 214 transmits the quality measurement packet to the quality measurement server 144 via the NNI path (S904). Thereby, the route quality measurement unit 218 measures the route quality of the NNI route. In the example shown in the figure, no congestion has occurred in the NNI path at this point.

  Next, the SIP server 142 transmits an INVITE message to the terminal adapter 200 (S906). Here, an example is shown in which the INVITE message does not reach the terminal adapter 200 due to congestion in the NNI route. The SIP server 142 starts executing the retransmission process 900 that periodically repeats the transmission of the INVITE message.

  Since the telephone 300 is in a standby state, the quality measurement packet transmission unit 214 continues to periodically transmit the quality measurement packet. In S908, the route quality measurement unit 218 detects congestion of the NNI route based on the quality measurement packet transmitted by the quality measurement packet transmission unit 214.

  The quality measurement packet transmission unit 214 transmits a quality measurement packet to the quality measurement server 144 via the UNI path in response to detecting congestion of the NNI path (S910). Here, a case where there is no congestion on the UNI path and the quality measurement packet reaches the quality measurement server 144 will be described as an example. However, if congestion occurs on the UNI path, the quality measurement packet is transmitted. The unit 214 may transmit the quality measurement packet to another UNI path. In this case, the quality measurement packet transmission unit 214 may sequentially transmit the quality measurement packets to a plurality of UNI paths until a UNI path that satisfies the path quality is detected. Further, the quality measurement packet transmission unit 214 may transmit the quality measurement packet to a plurality of UNI paths all at once.

  When the route quality determination unit 226 determines that the UNI route is not congested by the quality measurement packet transmitted in S910, the route registration unit 236 sends a REGISTER message to the SIP server to register the UNI route. 142 (S912). The SIP server 142 registers the UNI path as the communication path of the terminal adapter 200 by receiving the REGISTER message. Then, the SIP server 142 retransmits the INVEITE message via the UNI path (S914). As a result, the INVEITE message reaches the terminal adapter 200. Then, a call is established (S916).

  In FIG. 9, the INVITE (incoming request) message transmitted from the SIP server 142 to the terminal adapter 200 in S906 has been described as an example of not reaching the terminal adapter 200. Then, the quality measurement packet transmission unit 214 may transmit the quality measurement packet to the quality measurement server 144 via the NNI path. In this case, the route quality measurement unit 218 detects congestion of the NNI route based on the transmitted quality measurement packet, and the quality measurement packet transmission unit 214 determines the quality via the UNI route according to the detection. A quality measurement packet may be transmitted to the measurement server 144. Subsequent processing may be the same as after S912.

  As described above, when the terminal adapter 200 detects congestion on the NNI route, even if the NNI route is congested when the SIP server 142 transmits the INVITE message by registering the UNI route, A call can be established. Note that the SIP server 142 may repeat the retransmission process for a time longer than the time interval at which the terminal adapter 200 transmits the quality measurement packet. Accordingly, the retransmission process can be repeated until the terminal adapter 200 switches from the NNI path to the UNI path, and it is possible to prevent the retransmission process from being terminated before the call is established.

  In the above description, each unit of the terminal adapter 200 may be realized by hardware or may be realized by software. Further, it may be realized by a combination of hardware and software. For example, the computer may function as a part of the terminal adapter 200 by executing a program on the terminal adapter 200. The program may be stored in a computer-readable medium, or may be stored in a storage device connected to a network. In an information processing apparatus having a general configuration including a data processing apparatus having a CPU, ROM, RAM, communication interface, etc., an input apparatus, an output apparatus, and a storage apparatus, the operation of each part of the terminal adapter 200 is defined. The terminal adapter 200 may be realized by starting software or a program.

  A program that is installed in a computer and causes the computer to function as a part of the terminal adapter 200 according to this embodiment includes a module that defines the operation of each part of the terminal adapter 200. These programs or modules work on the CPU or the like to cause the computer to function as each part of the terminal adapter 200. Information processing described in these programs functions as a specific means in which software and the various hardware resources described above cooperate with each other by being read by a computer. A specific measurement device according to the purpose of use can be constructed by realizing calculation or processing of information according to the purpose of use of the computer in the present embodiment by these specific means.

  The SIP server 142 and the quality measurement server 144 include a data unit having a CPU, a ROM, a RAM, a communication interface, an input unit such as a keyboard, a touch panel, and a microphone, an output unit such as a display and a speaker, a memory, and an HDD. In an information processing apparatus having a general configuration including a storage unit such as the above, it may be realized by starting software or a program that defines the operation of each unit of the SIP server 142 and the quality measurement server 144.

  In the present embodiment, the terminal adapter 200 and the telephone 300 are described as separate bodies, but the present invention is not limited to this. The terminal adapter 200 and the telephone 300 may be integrated. That is, an IP telephone having the functions of the terminal adapter 200 and the telephone 300 may be used.

  Moreover, although this embodiment mainly demonstrated the case where a quality measurement packet was used for a path | route quality measurement, it is not restricted to this. The route quality measurement unit 218 may measure the route quality by another method capable of measuring the route quality.

  In the present embodiment, the case where the IP telephone service is targeted has been described as an example. However, the present invention is not limited to this, and other communication services that perform communication via NNI and UNI may be targeted.

  In the present embodiment, the case where the path quality measuring unit 218 performs actual call measurement when a call process by a user or a call by an incoming call is performed has been described as an example, but the present invention is not limited thereto. . For example, actual call measurement may be periodically performed on a predetermined communication partner. For example, in order to monitor the status of the communication network, actual call measurement may be periodically performed on a communication partner installed in another prefecture. At this time, for example, the terminal adapter 202 may register a bypass route based on the result of actual call measurement between the telephone 302 and the fixed telephone 152. Specifically, the terminal adapter 202 performs actual call measurement for a call with the fixed telephone 152 via the NNI route, and when the route quality does not exceed a predetermined standard, the UNI route is used as a bypass route. You may register.

  In the present embodiment, the terminal adapter 200 is described as an example of the communication device. However, the present invention is not limited to this, and the SIP server 142 or the quality measurement server 144 may be an example of the communication device. For example, the SIP server 142 includes a route quality measurement unit 218 and a congestion state determination unit 224. In this case, the SIP server 142 may measure the route quality of the NNI route and the UNI route by transmitting a quality measurement packet to the terminal adapter 200 via the NNI route and the UNI route, and determine the congestion state. It's okay. When it is determined that the route quality of the NNI route exceeds a predetermined reference, the SIP server 142 communicates with the terminal adapter 200 via the NNI route, and the route quality of the NNI route is determined in advance. If the standard is not exceeded, communication may be via the UNI path.

  The communication device may be another device that can communicate with the terminal adapter 200 and the SIP server 142. The other apparatus may include a route quality measurement unit 218, a route quality determination unit 226, and a communication control unit that controls communication between the terminal adapter 200 and the SIP server 142. Furthermore, the other device may include a communication unit 210, a history storage unit 220, an average time calculation unit 222, and a congestion state determination unit 224. In this case, the terminal adapter 200 may be an example of a communication terminal. The SIP server 142 may be an example of a server.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that it can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first,” “next,” etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

10 telephone systems, 110 NGN, 112 NNI, 114 UNI, 116 UNI, 118 UNI, 120 NGN, 122 NNI, 124 UNI, 126 UNI, 128 UNI, 130 connected carrier network, 140 IP telephone service network, 142 SIP server, 144 Quality measurement server, 150 PSTN, 152 landline telephone, 154 mobile phone, 164 bypass route, 166 bypass route, 168 bypass route, 174 bypass route, 176 bypass route, 178 bypass route, 182 accommodation device, 184 relay router, 186 GW Router, 188 accommodation device, 192 monitoring route, 194 call path, 200, 202, 204, 206, 208 terminal adapter, 210 communication unit, 212 off-hook detection unit, 214 quality measurement packet transmission unit, 2 6 Response reception unit, 218 Route quality measurement unit, 220 History storage unit, 222 Average time calculation unit, 224 Congestion state determination unit, 226 Route quality determination unit, 228 Route selection unit, 230 Calling unit, 232 Calling unit, 234 Call unit, 236 Route registration unit, 302, 304, 306, 308 Telephone, 414, 416, 418, 424, 426, 428 Relay adapter, 502 arrow, 514, 516, 518, 524, 526, 528 SBC, 900 Retransmission processing

Claims (6)

The frequency of measuring the first response time by transmitting a quality measurement packet to another communication device via the first communication path, and the frequency of transmitting the quality measurement packet to the other communication device via the first communication path. A path quality measurement unit that measures a second response time of a quality measurement packet transmitted to the other communication device via the second communication path at a low frequency;
A history storage unit for storing a history of the first response time measured by the path quality measurement unit;
An average response time calculation unit that calculates a first average response time that is an average of the plurality of first response times stored in the history storage unit;
Based on the first average response time calculated by the average response time calculation unit and the first response time newly measured by the path quality measurement unit, the congestion state of the first communication path is determined, and A congestion state determination unit that determines a congestion state of the second communication path based on a second response time;
A communication device comprising: The congestion state determination unit is congested in the first communication path when the first response time newly measured by the path quality measurement unit is longer than a predetermined time with respect to the first average response time. The communication device according to claim 1, wherein the communication device is determined to be a precursor to occurrence of a fault. A path quality determination unit that determines whether or not the congestion state of the first communication path determined by the congestion state determination unit satisfies a predetermined criterion;
When it is determined by the path quality determination unit that the congestion state of the first communication path satisfies the predetermined criterion, communication is performed via the first communication path, and the congestion state of the first communication path A communication unit that communicates via the second communication path when it is determined that does not satisfy the predetermined criterion;
The communication device according to claim 1, further comprising: The history storage unit stores a history of the second response time,
  The average response time calculation unit calculates a second average response time that is an average of the second response times stored in the history storage unit,
The congestion state determination unit is configured to provide congestion of the second communication path based on the second average response time calculated by the average response time calculation unit and the second response time newly measured by the path quality measurement unit. Determine the state,
4. The communication unit according to claim 3, wherein the communication unit communicates via the first communication path or the second communication path selected based on a congestion state of the first communication path and a congestion state of the second communication path. Communication device. 5. The device according to claim 1, wherein the first communication path is a path that passes through an NNI (Network-Network Interface), and the second communication path is a path that passes through a UNI (User-Network Interface). The communication apparatus as described in. The program for functioning a computer as a communication apparatus of any one of Claim 1 to 5.

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