JP5720007B2 - Mobile terminal device, communication device for communicating with the same, and communication network including them - Google Patents

Description

  The present invention relates to a mobile terminal device, a communication device that communicates with the mobile terminal device, and a communication network including them.

  With the development of various wireless communication infrastructures such as a wireless LAN (Local Area Network) and WiMAX, mobile terminals equipped with a plurality of wireless NICs (Network Interface Controllers) are becoming popular. In these terminals, by simultaneously using a plurality of NICs and distributing traffic at an appropriate ratio to a plurality of wireless networks, high communication quality (for example, high throughput, which cannot be obtained by a single wireless network, Moreover, it can be expected to achieve low-delay communication).

  A traffic distribution method at the data link layer level for enabling aggregation of a plurality of communication links of the same type and relatively stable in communication quality has been proposed (Non-Patent Document 1).

  Also, a method for enabling aggregation of a plurality of IP addresses at the network layer level based on MIPv6 has been proposed (Non-Patent Document 2). In normal MIPv6, only a single care-of address (CoA) can be associated with a single home address (HoA).

  On the other hand, in this method, it is possible to associate a plurality of CoAs with a single HoA by extending MIPv6. As a result, a terminal having a plurality of NICs obtains a different CoA for each NIC and associates it with the HoA, so that the traffic addressed to the HoA of the terminal is transferred to the HoA of the terminal on the home agent (HA). Distribution to a plurality of corresponding CoAs is possible.

  Furthermore, traffic distribution at the network layer level is realized using the method proposed in Non-Patent Document 2 as a basic technology (Non-Patent Document 3). This method achieves high throughput that cannot be obtained with a single link by distributing packets to each network at an appropriate rate using a packet as a unit of distribution for multiple networks to which terminals are connected. Yes.

J. Duncanson, “Inverse Multiplexing,” IEEE Communications Magazine, Vol. 32, No. 4, pp.34-41, 1994. R. Wakikawa, V. Devarapalli, G. Tsirtsis, T. Ernst, and K. Nagami, “Multiple Care-of Addresses Registration,” RFC 5648, 2009. K. Chebrolu, B. Raman, and R. R. Rao, “A Network Layer Approach to Enable TCP over Multiple Interfaces,” Wireless Networks, pp. 637-650, 2005.

  However, in the method of Non-Patent Document 1, since it is assumed that a plurality of links based on the same kind of data link layer protocol such as an ISDN line are aggregated, an access network provided by a plurality of communication line operators It is difficult to aggregate links that straddle

  Further, in the method of Non-Patent Document 3, traffic is distributed to a plurality of NICs possessed by a terminal using a packet as a unit of distribution. However, the communication quality characteristics of each network vary greatly depending on the protocol below the data link layer of the communication method. For example, in the WiFi network and the WiMAX network, as the MAC layer protocol, the former performs access control based on contention, whereas the latter performs access control based on scheduling, so the delay characteristics in packet transmission of both networks are ,to differ greatly.

  When distribution in units of packets is performed for a plurality of networks having different delay characteristics, there is a problem that the order of arrival of packets frequently changes, resulting in a decrease in throughput and an increase in delay in the transport layer and higher.

  Accordingly, the present invention has been made to solve such a problem, and an object of the present invention is to provide a mobile terminal apparatus that is resistant to the occurrence of congestion due to fluctuations in traffic volume.

  Another object of the present invention is to provide a communication device that communicates with a mobile terminal device that is resistant to the occurrence of congestion due to fluctuations in traffic volume.

  Furthermore, another object of the present invention is to provide a communication network including a mobile terminal device that is resistant to the occurrence of congestion due to fluctuations in traffic volume.

  According to the embodiment of the present invention, the mobile terminal device includes a plurality of wireless communication devices and a control device. Each of the plurality of wireless communication devices performs communication via a base station. The control device controls communication between a communication device installed on the network and a plurality of wireless communication devices. The control device is a network path from the communication device to each wireless communication device via the base station, and the direction from the communication device to the wireless communication device and the direction from the wireless communication device to the communication device. If the path that distinguishes the path is defined as a route, and the traffic flow on the route is defined as a flow, the capacity of all the routes through which the flow passes and the available bandwidth of all the routes are detected. When the capacity of any one of the paths exceeds, the flow passing through the path whose capacity has exceeded is moved to another path so that the minimum value of the usable bandwidth of all the paths becomes maximum.

  According to the embodiment of the present invention, the communication device is a communication device installed on a network, and includes a communication device and a control device. The communication device performs communication via the base station. The control device controls communication between the plurality of wireless communication devices equipped in the mobile terminal device and the communication device. Each of the plurality of wireless communication devices communicates with the communication device via the base station. The control device is a network path from the communication device to each wireless communication device via the base station, and distinguishes the direction from the communication device to the wireless communication device and the direction from the wireless communication device to the communication device. If the path to be used is defined as a route, and the flow of traffic on the route is defined as a flow, the capacity of all the routes through which the flow passes and the available bandwidth of all the routes are detected. When the capacity of any of the paths exceeds, the flow passing through the path whose capacity has exceeded is moved to another path so that the minimum value of the available bandwidth of all the paths becomes maximum.

  Furthermore, according to the embodiment of the present invention, the communication network includes a plurality of mobile terminal devices, a communication device, and a control device. Each of the plurality of mobile terminal devices is equipped with a plurality of wireless communication devices. The communication device is installed on the network and communicates with a plurality of mobile terminal devices via the base station. The control device controls wireless communication between the plurality of mobile terminal devices and the communication device. Each of the plurality of wireless communication devices communicates with the communication device via the base station. The control device is a path on the network from the communication device to each wireless communication device via the base station, and distinguishes the direction from the communication device to the wireless communication device and the direction from the wireless communication device to the communication device. If the path to be used is defined as a route, and the flow of traffic on the route is defined as a flow, the capacity of all the routes through which the flow passes and the available bandwidth of all the routes are detected. When the capacity of any of the paths exceeds, the flow passing through the path whose capacity has exceeded is moved to another path so that the minimum value of the available bandwidth of all the paths becomes maximum.

  In the embodiment of the present invention, the control device selects a route whose capacity overflows so that the minimum value of the usable bandwidth of all routes between the communication device and the wireless communication device of the mobile terminal device is maximized. Move the flow through to another path. As a result, a maximum margin is created in the usable bandwidth of the communication network.

  Accordingly, it is possible to withstand the occurrence of congestion due to fluctuations in traffic volume.

1 is a schematic diagram of a communication network according to an embodiment of the present invention. It is a block diagram of the home agent shown in FIG. It is a block diagram of the mobile terminal apparatus shown in FIG. It is a figure for demonstrating a path | route and a flow. It is a figure which shows the relationship between the capacity | capacitance of a path | route, and an available zone | band. It is a figure which shows the node which measures a transmission rate and a reception rate. It is a conceptual diagram of the overflow of the capacity | capacitance of a path | route. It is a conceptual diagram of route aggregation. It is a figure which shows the conditions which determine the necessity of the movement of a flow. It is a conceptual diagram of the movement of a flow. It is a flowchart which shows a flow distribution algorithm. It is a timing chart which shows the whole operation | movement which moves a flow.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a schematic diagram of a communication network according to an embodiment of the present invention. Referring to FIG. 1, a communication network 100 according to an embodiment of the present invention includes a home agent 10, a network 20, access points 30, 40, 50, mobile terminal devices 60, 70, and terminal devices 80, 90. With.

  The home agent 10 is arranged on the network 20. The home agent 10 receives packets from the mobile terminal devices 60 and 70 via the network 20 and the access points 30, 40 and 50, and transmits the received packets to the terminal devices 80 and 90. The home agent 10 receives packets from the terminal devices 80 and 90 and transmits the received packets to the mobile terminal devices 60 and 70 via the network 20 and the base stations 30, 40 and 50.

  Further, the home agent 10 controls communication between the home agent 10 and the mobile terminal devices 60 and 70 by a method described later.

  The access point 30 is connected to the network 20 by a wired cable. The access point 30 forms a WiFi network, for example. The access point 30 receives a packet from the home agent 10 and transmits the received packet to the mobile terminal device 60 by wireless communication. In addition, the access point 30 receives a packet from the mobile terminal device 60 through wireless communication, and transmits the received packet to the home agent 10.

  The access point 40 is connected to the network 20 by a wired cable. The access point 40 forms a WiFi network, for example. The access point 40 receives a packet from the home agent 10 and transmits the received packet to the mobile terminal device 60 or the mobile terminal device 70 by wireless communication. Further, the access point 40 receives a packet from the mobile terminal device 60 or the mobile terminal device 70 by wireless communication, and transmits the received packet to the home agent 10.

  The access point 50 is connected to the network 20 by a wired cable. The access point 50 forms a WiMAX network, for example. The access point 50 receives a packet from the home agent 10 and transmits the received packet to the mobile terminal device 70 by wireless communication. In addition, the access point 50 receives a packet from the mobile terminal device 70 by wireless communication, and transmits the received packet to the home agent 10.

  The mobile terminal device 60 performs wireless communication with the access points 30 and 40 by any wireless communication method such as WiFi (IEEE802.11), WiMAX (IEEE802.16), and 3G (W-CDMA, CDMA2000).

  In addition, the mobile terminal device 70 performs wireless communication with the access points 40 and 50 by any wireless communication method such as WiFi (IEEE802.11), WiMAX (IEEE802.16), and 3G (W-CDMA, CDMA2000). .

  Each of the terminal devices 80 and 90 is connected to the home agent 10 by a wired cable. Each of the terminal devices 80 and 90 transmits a packet addressed to the mobile terminal devices 60 and 70 to the home agent 10 and receives a packet addressed to itself from the home agent 10.

  FIG. 2 is a configuration diagram of the home agent 10 shown in FIG. Referring to FIG. 2, home agent 10 includes communication devices 11 and 13 and control device 12.

  The communication device 11 receives a packet from the access points 30, 40, 50 via a wired cable, and outputs the received packet to the control device 12.

  The communication device 11 receives a packet from the control device 12, and transmits the received packet to the access points 30, 40, and 50 via a wired cable.

  The control device 12 receives a packet from the communication device 11. When the destination of the received packet is the terminal device 80 or 90, the control device 12 outputs the packet to the communication device 13. In addition, when the transmission destination of the received packet is the home agent 10, the control device 12 receives the packet.

  The control device 12 receives a packet from the communication device 13 and outputs the received packet to the communication device 11.

  Furthermore, the control device 12 controls communication between the communication device 11 and the mobile terminal devices 60 and 70 by a method described later.

  The communication device 13 receives a packet from the control device 12 and transmits the received packet to the terminal devices 80 and 90. The communication device 13 receives packets from the terminal devices 80 and 90, and outputs the received packets to the control device 12.

  FIG. 3 is a configuration diagram of the mobile terminal device 60 shown in FIG. Referring to FIG. 3, mobile terminal apparatus 60 includes antennas 61 and 62 and radio communication devices 63 and 64.

  The wireless communication device 63 performs wireless communication via the access point 30 and the antenna 61 in accordance with the WiFi communication method. The wireless communication device 64 performs wireless communication with the access point 40 and the antenna 62 in accordance with the WiFi communication method.

  As described above, the wireless communication devices 63 and 64 perform wireless communication with the access points 30 and 40, respectively, according to the same communication method or different communication methods.

  1 also has the same configuration as the mobile terminal device 60 shown in FIG.

  FIG. 4 is a diagram for explaining a route and a flow. With reference to FIG. 4, a route r <b> 1 is a path including the communication device 11 of the home agent 10, the access point 30, and the wireless communication device 63 of the mobile terminal device 60.

  The route r2 is a path including the wireless communication device 63 of the mobile terminal device 60, the access point 30, and the communication device 11 of the home agent 10.

  Furthermore, the route r3 is a path including the wireless communication device 64 of the mobile terminal device 60, the access point 40, and the communication device 11 of the home agent 10.

  Further, the route r4 is a path including the communication device 11 of the home agent 10, the access point 40, and the wireless communication device 64 of the mobile terminal device 60.

  As described above, the routes r1 to r4 include a path between the communication device 11 of the home agent 10 and the wireless communication devices 63 and 64 of the mobile terminal devices 60 and 70. The routes r1 to r4 are different routes if the directions are different. Therefore, in the embodiment of the present invention, the route is a path on the network from the home agent 10 to the wireless communication devices 63 and 64 via the access points 30, 40 and 50, and the home agent. 10 is defined as a path that distinguishes the direction from the wireless communication devices 63 and 64 to the home agent 10 from the wireless communication devices 63 and 64.

  In the embodiment of the present invention, a flow is defined as a traffic flow on a route.

  One of the following two methods is used as a method for identifying the flow. First, the first method identifies a flow using a transmission source IP address, a reception destination IP address, a transmission source port number, a reception destination port number, and a transport layer identification number. Another method is used for IPv6 packets and identifies a flow using a source IP address, a destination IP address, and a flow label.

  Furthermore, in the embodiment of the present invention, the capacity of a path means the maximum rate that can be achieved when a flow is caused to flow through a path and there is no other flow that flows through the path. , Expressed in units of bps.

  Furthermore, in the embodiment of the present invention, the available bandwidth means that when a certain flow is caused to flow in a certain route, that flow can be achieved within a range that does not affect the reception rate of other flows that flow in that route. Say the maximum rate. The available bandwidth is calculated by a method described later using the flow transmission rate and the reception rate.

  FIG. 5 is a diagram illustrating the relationship between the path capacity and the available bandwidth. Referring to FIG. 5, the available bandwidth is calculated by subtracting the consumed bandwidth from the path capacity.

  FIG. 6 is a diagram illustrating a node that measures a transmission rate and a reception rate. Referring to FIG. 6, the flow that flows from home agent 10 toward mobile terminal device 60 is a downlink flow. The flow that flows from the mobile terminal device 60 toward the home agent 10 is an uplink flow.

  In the downlink flow, the communication device 11 of the home agent 10 measures the transmission rate, and the wireless communication device 63 (or the wireless communication device 64) of the mobile terminal device 60 measures the reception rate. In the uplink flow, the radio communication device 63 (or the radio communication device 64) of the mobile terminal device 60 measures the transmission rate, and the communication device 11 of the home agent 10 measures the reception rate.

  In this case, the transmission rate and the reception rate are represented by the number of bits per unit time (bps).

The transmission rate of a certain flow is, for example, the number of bits of each packet p _i (i = 1, 2,..., N), assuming that n packets are transmitted per t seconds within the OS. Is B (p _i ), the transmission rate is represented by (SUM ⁿ _{i = 1} B (p _i )) / t. The reception rate is calculated in the same way.

The notation SUM means that the sum of B ( _pi ) is calculated for i = 1, 2,..., N.

  Then, the wireless communication device 63 (or the wireless communication device 64) of the mobile terminal devices 60 and 70 periodically transmits the measured transmission rate and reception rate to the control device 12 of the home agent 10.

  In a certain route r, a set of all flows passing through the route is defined as F (r). For a flow fεF (r) passing through the route r, the transmission rate of the flow f is S (f) and the reception rate is R (f).

  Then, a state where the capacity of the route does not exceed in a certain route means a state where a reception rate R (f) equal to the transmission rate S (f) is achieved in all flows passing through the route. . That is, the state where the capacity of the route r is not over means that the following equation is established for the route r.

  Moreover, the state where the capacity of the route r is over means that the following equation is established for the route r.

  FIG. 7 is a conceptual diagram of the capacity overflow of the path. With reference to (a) of FIG. 7, two flows are flowing through a path having a capacity of 8 Mbps. The transmission rate of one flow is 3 Mbps, and the transmission rate of the other flow is 2 Mbps. Also, the reception rate of one flow is 3 Mbps, and the reception rate of the other flow is 2 Mbps.

  Therefore, a reception rate equal to the transmission rate is achieved in two flows that take a path having a capacity of 8 Mbps. That is, the path capacity does not overflow.

  Referring to FIG. 7B, two flows are flowing through a path having a capacity of 8 Mbps. The transmission rate of one flow is 7 Mbps, and the transmission rate of the other flow is 4 Mbps. The reception rate of one flow is 5 Mbps, and the reception rate of the other flow is 3 Mbps.

  Therefore, in two flows taking a path having a capacity of 8 Mbps, a reception rate equal to the transmission rate is not achieved, and the sum of the reception rates (= 8 Mbps) is smaller than the sum of the transmission rates (= 11 Mbps). That is, the path capacity overflows. In this case, the sum of the reception rates (= 8 Mbps) represents the capacity of the route.

  The control device 12 of the home agent 10 periodically collects the transmission rate and reception rate measured by the communication device 11 and the transmission rate and reception rate measured by the wireless communication devices 63 and 64 of the mobile terminal devices 60 and 70. .

  And the control apparatus 12 of the home agent 10 is based on the collected transmission rate and reception rate, among all the paths between the communication apparatus 11 and the wireless communication apparatuses 63 and 64 of the mobile terminal apparatuses 60 and 70. It is determined whether the capacity of at least one path has overflowed. That is, the control device 12 of the home agent 10 determines whether or not Expression (2) is satisfied based on the collected transmission rate and reception rate, thereby determining the capacity of at least one of all the routes. It is determined whether or not the overflow has occurred.

  When the control device 12 of the home agent 10 determines that the capacity of at least one of the routes has overflowed, the communication device 11 and the wireless communication devices 63 and 64 of the mobile terminal devices 60 and 70 The flow of the path whose capacity has overflowed is moved to another path so that the minimum value of the available bandwidth in all the paths in between is maximized. This is called a “flow distribution algorithm”.

In this case, the control device 12 of the home agent 10 estimates the capacity of the route r as SUM _{fεF (r)} R (f) if the equation (2) is established in a certain route r.

  The capacity of each path is updated with the passage of time using the latest transmission rate and reception rate at that time. In an actual environment, due to a measurement error between the flow transmission rate and the reception rate, the equation (2) may actually be satisfied even though the path capacity does not overflow. In such a case, in order to prevent the estimated value of the capacity of the route from being updated to an incorrect value, the control device 12 of the home agent 10 holds the threshold value T, and in the route where the following equation is established. Only update the capacity of the route.

  Note that the threshold T is set to 1 Mbps, for example.

  In addition, since the capacity of the route is estimated only after the expression (2) is established, the control device 12 of the home agent 10 determines that the capacity is not estimated once in the initial stage of control. Given an initial value, consider it as the capacity of the path and execute the flow distribution algorithm. The initial value of the capacity of the route is set to 10 Mbps, for example.

  FIG. 8 is a conceptual diagram of route aggregation. In a wireless communication environment, the capacity of a certain route is often shared with other routes. For example, as shown in FIG. 8, it is assumed that two mobile terminal devices 60 and 70 are connected to the same access point 40 for communication.

  Regarding the route in the downlink direction (direction from the home agent 10 to the mobile terminal devices 60 and 70), since there is one route for each mobile terminal device 60 and 70, the estimated value of the capacity of the route described above is Calculated for each route.

  However, in practice, the two mobile terminal devices 60 and 70 are both located within the radio wave range of the same access point 40 and perform wireless communication while sharing a space with each other. As a result, for example, under the access control by WiFi, the two mobile terminal devices 60 and 70 cannot communicate with the access point 40 simultaneously, and can communicate with the access point 40 at any moment. Is one of the mobile terminal devices 60 and 70. Therefore, the mobile terminal device 60 and the mobile terminal device 70 are in a state of sharing the path capacity with each other.

  In such a state, it is not desirable to estimate the capacity by regarding the two paths as independent.

  Therefore, in the embodiment of the present invention, a plurality of routes passing through the same access point are aggregated, and the capacity is estimated by regarding the plurality of routes as one route.

More specifically, the control device 12 of the home agent 10 estimates the capacity by aggregating m (m is an integer of 2 or more) routes r _i (i = 1, 2,..., M). In this case, assuming that the route after aggregation is r, the set of all flows passing through r is F (r) = U ^m _{i = 1} F (r _i ), and Equation (2) is established for F (r). Then, the capacity of the route r is estimated as SUM _{fεF (r)} R (f).

  In the following, even an actually aggregated route is simply called a route.

  A flow distribution algorithm will be described. A set of all routes in the network to be controlled is P, and a set of all flows that pass through each route rεP before executing the flow distribution algorithm is F (r).

  The control device 12 of the home agent 10 calculates the available bandwidth of all paths P based on the transmission rate and reception rate of all flows. Then, the control device 12 of the home agent 10 moves the flow passing through the route whose capacity has overflowed to another route so that the calculated minimum usable bandwidth of all the routes P becomes the maximum. This will be specifically described.

  When the estimated value of the capacity of each route rεP before executing the flow distribution algorithm is C (r), the available bandwidth A (r) is obtained by the following equation.

  That is, the available bandwidth A (r) is a value obtained by subtracting the sum of the transmission rates of all flows passing through the route r from the estimated value C (r) of the route r.

  In the state where the capacity overflows, A (r) is a negative value.

  The flow distribution algorithm changes the flow fεF (r) passing through a certain route rεP so as to pass another route r′εP, whereby the available bandwidth A (r) in both routes r and r ′. Is increased, the flow f is moved from the route r to the route r ′.

  FIG. 9 is a diagram showing conditions for determining whether or not a flow movement is necessary. Referring to (a) of FIG. 9, in two routes r and r ′, available bandwidths A (r) and A (r ′) are 4 Mbps and 1 Mbps, respectively.

  At this time, if the flow f passing through the route r ′ is changed to pass through the route r, the available bandwidths A (r) and A (r ′) become 3 Mbps and 2 Mbps, respectively (see FIG. 9B). ).

  As a result, the minimum value of the available bandwidth is 1 Mbps before the movement of the flow, but increases to 2 Mbps after the movement of the flow.

  For each flow, the flow distribution algorithm moves the flow when the minimum value of the available bandwidths A (r) and A (r ′) of the two routes r and r ′ increases by moving the flow.

  The control device 12 of the home agent 10 executes the above-described flow distribution algorithm for all paths whose capacity has overflowed. As a result, the control device 12 of the home agent 10 moves the flow through the route whose capacity has overflowed to another route so that the minimum value of the available bandwidth of all the routes in the communication network 100 is maximized.

  It is not always possible to move a flow f that passes through a certain route r to another route r '. That is, the fact that the flow f can be moved from the route r to the route r ′ means that the directions of the route r and the route r ′ are the same, and the mobile terminal device that is the transmission source (or reception destination) of the flow is the route Only when a wireless communication device connected to an access point on r ′ is installed.

  FIG. 10 is a conceptual diagram of flow movement. Referring to (a) of FIG. 10, the flow f <b> 1 flows along a route that reaches the mobile terminal device 60 via the access point 30. It is possible to move to a route that reaches the mobile terminal device 60 via the flow f access point 40 (see FIG. 10B).

  The direction of the route r passing through the access point 30 and the route r ′ passing through the access point 40 are the same, and the mobile terminal device 60 that receives the flow f is connected to the access point 40 on the route r ′. This is because a wireless communication device 64 is provided.

  However, since the mobile terminal device 60 is not equipped with a wireless communication device connected to the access point 50, the flow f cannot be moved from the route r to the route via the access point 50.

  Therefore, the control device 12 of the home agent 10 selects the route r ′ that matches the above-described condition as the route that can be moved.

  In the following, a set of destination routes that can move the flow f is denoted by M (f).

  FIG. 11 is a flowchart showing a flow distribution algorithm. Referring to FIG. 11, when the flow distribution algorithm is started, the control device 12 of the home agent 10 sets the set F (r) of all flows passing through each route rεP and the set M ( f) is acquired, and the estimated value C (r) and the available bandwidth A (r) of the capacity of each route rεP are calculated (step S1).

  Then, the control device 12 of the home agent 10 selects one flow f (step S2), and selects a route r through which the selected flow f flows (step S3).

  Thereafter, the control device 12 of the home agent 10 selects the route r ′ that is the destination of the route r (step S4), and x = min (A (r), A (r ′)) and x ′ = min ( A (r) + S (f), A (r ′) − S (f)) is calculated (step S5).

  Then, the control device 12 of the home agent 10 determines whether x 'is larger than x (step S6).

  When it is determined in step S6 that x 'is not larger than x, the control device 12 of the home agent 10 selects another route r' (step S7). Thereafter, the series of operations returns to step S5, and step S5 to step S7 described above are repeatedly executed until it is determined in step S6 that x 'is larger than x.

  When it is determined in step S6 that x ′ is larger than x, the control device 12 of the home agent 10 determines that A (r) = A (r) + S (f) and A (r ′) = A ( r ′) − S (f) is set (step S8). That is, the control device 12 of the home agent 10 updates the available bandwidths A (r) and A (r ′).

  Then, the control device 12 of the home agent 10 moves the flow f from the route r to the route r ′ (step S9).

  In this case, the control device 12 of the home agent 10 moves the flow by controlling the communication device 11 to change the destination address (access point address) of the flow when the moving flow is in the downlink direction. To do. When the moving flow is in the upward direction, the control device 12 of the home agent 10 transmits a movement request for the flow to the mobile terminal device (one of the mobile terminal devices 60 and 70), and the mobile terminal device (moving Any of the terminal devices 60 and 70) changes the flow source address according to the movement request, thereby realizing the movement of the flow.

  Thereafter, the control device 12 of the home agent 10 further determines whether or not Steps S5 to S9 have been executed for all the flows F (f) (Step S10).

  In Step S10, when it is determined that Steps S5 to S9 are not executed for all the flows F (f), the control device 12 of the home agent 10 selects another flow (Step S11). And a series of operation | movement returns to step S3, and step S3-step S11 are repeatedly performed until it determines with step S5-step S9 having been performed with respect to all the flows F (f) in step S11. .

  In step S11, when it is determined that steps S5 to S9 have been executed for all the flows F (f), the flow distribution algorithm ends.

  FIG. 12 is a timing chart showing the overall operation of moving the flow. Referring to FIG. 12, home agent 10 receives the transmission rate and reception rate of each flow from mobile terminal apparatuses A to Z in period J (J is a positive integer).

  Then, the home agent 10 executes the flow distribution algorithm shown in FIG. 11 using the received transmission rate and reception rate. In this case, when an upstream flow is moved, the home agent 10 transmits a movement request for the flow to the mobile terminal device (any of the mobile terminal devices A to Z), and the mobile terminal device (the mobile terminal device A). -Z) changes the source address of the flow according to the movement request. When the downstream flow is moved, the home agent 10 controls the communication device 11 so as to change the reception destination address (access point address) of the flow. As a result, the flow is moved.

  When the cycle J ends, the above-described operation is repeated in the cycle J + 1. Thereafter, the above-described operation is periodically repeated.

  As described above, in the embodiment of the present invention, the control device 12 of the home agent 10 determines the available bandwidth of all paths between the communication device 11 and the wireless communication devices 63 and 64 of the mobile terminal devices 60 and 70. The flow through the path whose capacity has overflowed is moved to another path so that the minimum value becomes maximum.

  As a result, a maximum margin is created in the usable bandwidth of the communication network 100. Accordingly, it is possible to withstand the occurrence of congestion due to fluctuations in traffic volume.

  In the above description, it has been described that the control device 12 that executes the flow distribution algorithm is provided in the home agent 10. However, in the embodiment of the present invention, the control device 12 is not limited thereto. It may be installed in any one of the mobile terminal devices 60 and 70, and in general, it may be present at any position within the communication network 100.

  In the above description, each of the mobile terminal apparatuses 60 and 70 has been described as including two wireless communication devices 63 and 64. However, the embodiment of the present invention is not limited to this, and the mobile terminal is not limited thereto. Each of the devices 60, 70 may include three or more wireless communicators. In that case, each of the mobile terminal devices 60 and 70 may include a plurality of wireless communication devices that perform wireless communication according to the same wireless communication method, and a plurality of wireless communication devices that perform wireless communication according to different wireless communication methods. May be provided.

  Furthermore, in the embodiment of the present invention, the home agent 10 constitutes a “communication device”, and the mobile terminal devices 60 and 70 constitute “a plurality of mobile terminal devices”.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  The present invention is applied to a mobile terminal device, a communication device that communicates with the mobile terminal device, and a communication network including them.

  10 home agent, 11, 13 communication device, 12 control device, 20 network, 30, 40, 50 access point, 60, 70 mobile terminal device, 61, 62 antenna, 63, 64 wireless communication device, 80, 90 terminal device, 100 Communication network.

Claims (6)

A plurality of wireless communication devices each communicating via a base station;
A control device for controlling communication between a communication device installed on a network and the plurality of wireless communication devices;
The control device is a path on the network from the communication device to each wireless communication device via the base station, and the direction from the communication device to the wireless communication device and the communication from the wireless communication device. When a path that distinguishes the direction to the device is defined as a route, and the flow of traffic on the route is defined as a flow, the capacity of all the routes through which the flow passes and the usable bandwidth of all the routes And when the capacity of any one of the paths is over, the usable area of the path with the capacity exceeding the minimum value of the available bandwidth of all the paths increases. The mobile terminal device moves a flow that passes through the route that has exceeded the capacity to another route. A communication device installed on a network,
A communication device that communicates via a base station;
A plurality of wireless communication devices equipped in a mobile terminal device and a control device for controlling communication between the communication devices,
Each of the plurality of wireless communication devices communicates with the communication device via the base station,
The control device is a network path from the communication device to each wireless communication device via the base station, and the direction from the communication device to the wireless communication device and the communication from the wireless communication device. When the path that distinguishes the direction to the device is defined as a route, and the flow of traffic on the route is defined as a flow, the capacity of all the routes through which the flow passes and the usable bandwidth of all the routes And when the capacity of any one of the paths is over, the usable area of the path with the capacity exceeding the minimum value of the available bandwidth of all the paths increases. A communication device that moves a flow that passes through a route that exceeds the capacity to another route. A plurality of mobile terminal devices each equipped with a plurality of wireless communication devices;
A communication device installed on a network and communicating with the plurality of mobile terminal devices via a base station;
A control device for controlling wireless communication between the plurality of mobile terminal devices and the communication device;
Each of the plurality of wireless communication devices communicates with the communication device via the base station,
The control device is a path on the network from the communication device to each wireless communication device via the base station, and the direction from the communication device to the wireless communication device and the communication from the wireless communication device. When a path that distinguishes the direction to the device is defined as a route, and the flow of traffic on the route is defined as a flow, the capacity of all the routes through which the flow passes and the usable bandwidth of all the routes And when the capacity of any one of the paths is over, the usable area of the path with the capacity exceeding the minimum value of the available bandwidth of all the paths increases. As described above, a communication network that moves a flow that passes through a route that exceeds the capacity to another route.   The communication network according to claim 3, wherein the control device is provided in the communication device. The control device aggregates a plurality of routes between the communication device and the plurality of wireless communication devices into one route when a plurality of wireless communication devices perform wireless communication via one base station. When the capacity of any one of the paths is over, the aggregated path is used to use the path with the capacity exceeding the minimum value of the available bandwidth of all the paths. The communication network according to claim 3 or 4, wherein a flow passing through the route with the capacity over is moved to another route so that a possible area increases . The control device based on the transmission rate and the reception rate of each flow, the difference is the threshold of the sum of the reception rate of all flows through all of the flow the one path the sum of the transmission rates of through one path The update processing for updating the estimated value of the capacity of the one route when it is determined that the difference is larger than the threshold value is executed for the route having the difference larger than the threshold value. Communication network.

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