JP6504608B2 - Communication device, control method therefor, program, and communication system - Google Patents

Description

  The present invention relates to a packet communication system.

  The 2015 Long Term Evolution (LTE), which has become widespread, has been standardized by the 3rd Generation Partnership Project (3GPP), and all-IP (Internet Protocol) of mobile communication systems, with a maximum requirement of 100Mbps downstream and 50Mbps upstream. Speed and functionality of the conventional mobile communication system.

  The IEEE 802.11 standard Wi-Fi (registered trademark) has various standards depending on the frequency band and communication system to be used, and many standards are characterized by using unlicensed bands (unlicensed frequency bands). The IEEE802.11ac standardized in 2014 uses the 5 GHz band and achieves maximum speed exceeding 1 Gbps by expanding the available bandwidth and using Multi-Input Multi-Output (MIMO) technology.

  In addition, the next generation mobile communication system, such as LAA (Licensed-Assisted Access using LTE) that communicates by LTE using an unlicensed band such as 2.4 GHz band or 5 GHz band as currently used in Wi-Fi in 3GPP 5G (5th generation mobile communication system) is under consideration. In 5G, higher speed, lower delay, and power saving are listed as requirements of the existing mobile communication system, and utilization of a frequency band of 60 GHz or more such as millimeter waves is being considered.

  On the other hand, TCP / IP (Transmission Control Protocol / Internet Protocol) protocol is standardly used in general End to End communication of the Internet.

  CUBIC (see Non-Patent Document 1), which is a TCP congestion control algorithm that has become standard in Linux (registered trademark) at present, has congestion window sizes that represent the amount of packets that can be sent at one time depending on Round Trip Time (RTT). Improve throughput in high latency environments as it depends on the elapsed time from packet loss.

  Besides TCP, various controls have been proposed for TCP and can be used as options.

  Quick-Start (see Non-Patent Document 2) is a method for changing the window size requested by the transmission side to a window size corresponding to the requested throughput if all nodes between the transmission and reception approve. In order to use this option, all nodes between transmission and reception need to support Quick-Start, but it is possible to rapidly increase throughput.

  MPTCP (Multipath TCP) (see Non-Patent Document 3) is a method of dividing TCP communication into sub-flows and improving throughput and redundancy by using a plurality of paths.

  Further, Non-Patent Document 4 proposes a method of switching proprietary protocols such as RPS (Random Packet System) and UNAP (Universal Network Acceleration Protocol) in addition to TCP according to network characteristics and application characteristics.

Injong Rhee, and Lisong Xu, "CUBIC: A New TCP-Friendly High-Speed TCP Variant", 2008 S. Floyd, 3 others, "Quick-Start for TCP and IP", IETF, RFC 4782, January 2007 A. Ford, 3 others, "TCP Extensions for Multipath Operation with Multiple Addresses", IETF, RFC 6824, January 2013 Yuichi Mutoh, Naoki Oguchi, Yosuke Takano, Hiroshi Asagahiro, "A Study on Adaptive Selection Technique of Communication Protocol According to Communication Environment", IEICE Technical Report, IN 2012-184 (2013-03)

  In the 5G era, it is assumed that a plurality of radio access technologies (RATs), which are called heterogeneous environments (differential mixed environments) and have different characteristics such as used frequency bands and cell radius, are mixed (see FIG. 1). In addition to the existing LTE and Wi-Fi, RAT to be used may be, for example, an ultra-wide band using high-frequency millimeter waves but with a small cell radius or an inexpensive but high error rate using an unlicensed band . In such a heterogeneous environment, small cells with a cell radius of several meters to several hundreds of meters are interspersed, so it is considered that changes in the communication environment frequently occur due to cell switching accompanying travel by train or car.

  The above-mentioned CUBIC, a TCP congestion control algorithm, is a method that improves the fairness with RTT and other TCP flows while improving the throughput in a wide-band, high-latency environment that has been an issue in intercontinental communication etc. It was not designed to keep pace with the rapid changes in the communication environment. For this reason, even if switching to an ultra-wide band RAT with a cell radius of several meters during CUBIC communication, the throughput is not rapidly increased to prevent congestion. Therefore, if it is moving, the problem is that the cell is left before the band is fully used up. In addition, since CUBIC judges packet loss as congestion, when using a high error rate unlicensed band, it is a problem that packet loss due to an error occurs frequently and the throughput is unnecessarily reduced.

  Since multiple networks can be used in MPTCP, redundancy can be ensured, but when dividing flows, passive congestion control with fairness taken into consideration, negotiation, connection establishment, etc. Because of the overhead, the effect of rapidly increasing the throughput can not be expected.

  When switching to a wideband cell, throughput can be improved in a short time by using Quick-Start or UDP (User Datagram Protocol) without congestion control, but the possibility of causing congestion when leaving the broadband cell There is. Also, when changing to a high error rate cell, throughput can be maintained by performing control so as not to react excessively to packet loss. Although there are protocols and controls suitable for each environment as described above, the problem is that there is no transport technology that can cope with all environmental changes.

  Although the method described in Non-Patent Document 4 can change the protocol according to the environment, a mechanism for using a plurality of networks in a heterogeneous environment or the like is not considered.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a communication apparatus capable of promptly responding to a rapid change in communication environment, a control method therefor, and a communication system.

In order to achieve the above object, the present invention divides the transport layer of the OSI 7 hierarchical model into an upper layer and a lower layer in a communication apparatus for transmitting and receiving packets, and a plurality of transport protocol processors in the lower layer. An upper layer is provided with an integrated management function unit that integrates and manages communication by a plurality of transport protocol processing units, and the integrated management function unit is a communication that monitors a communication environment of communication by the transport protocol processing unit. An environment monitoring unit, and when the communication environment monitoring unit detects a change in the communication environment, one or more transport protocol processing units suitable for the changed communication environment are selected, and the selected one or more transport protocol processing units are selected. a communication scheme selection section that switches the communication, the communication method selection section has multiple tiger Characterized in that a sequence number management unit when the switching to communication by Sport protocol processing unit allocating a common sequence number in the packet according to the flow from the transport protocol processing unit.
In the communication apparatus for transmitting and receiving packets, the present invention divides the transport layer of the OSI 7 hierarchical model into the upper layer and the lower layer, and arranges a plurality of transport protocol processing units in the lower layer, and Includes an integrated management function unit that integrates and manages communication by a plurality of transport protocol processing units, the integrated management function unit including a communication environment monitoring unit that monitors a communication environment of communication performed by the transport protocol processing unit; Communication environment selection unit selects one or more transport protocol processing units suitable for the changed communication environment when the communication environment monitoring unit detects a change in communication environment, and selects a communication method to switch to communication by the selected one or more transport protocol processing units And the communication scheme selection unit is a first transport protocol When switching from communication by the management unit to communication by the first and second transport protocol processing units, a subflow by the second transport protocol processing unit is added to the flow by the existing first transport protocol processing unit And a sub-flow adding unit.
In the communication apparatus for transmitting and receiving packets, the present invention divides the transport layer of the OSI 7 hierarchical model into the upper layer and the lower layer, and arranges a plurality of transport protocol processing units in the lower layer, and Includes an integrated management function unit that integrates and manages communication by a plurality of transport protocol processing units, the integrated management function unit including a communication environment monitoring unit that monitors a communication environment of communication performed by the transport protocol processing unit; Communication environment selection unit selects one or more transport protocol processing units suitable for the changed communication environment when the communication environment monitoring unit detects a change in communication environment, and selects a communication method to switch to communication by the selected one or more transport protocol processing units And the first transport group selected by the communication scheme selection unit. A retransmission control unit for performing retransmission control of packets in the first transport protocol processing unit using the communication path related to the second transport protocol processing unit when the communication processing unit does not have retransmission control; It is characterized by

  According to the present invention, when a change in the communication environment such as the RAT is detected, switching to a transport protocol suitable for the environment maximizes throughput in a short time when reaching ultra-wide band, and achieves high error rate. It becomes possible to control to maximize the QoS under each environment, such as not to reduce the throughput unnecessarily when it becomes. By being able to use the ultra-wide band in a short time, it is possible to realize downloading of large-capacity files using small cells even while moving. Communication traffic can be distributed by effectively using small cells, and congestion of license bands such as LTE can be avoided. In addition, by using a plurality of RATs together, stable communication can be maintained even in a heterogeneous environment where the redundancy is high and cell switching frequently occurs when moving.

  Furthermore, since control of protocol switching is performed in the transport layer, it is not necessary for the application side to perform control in accordance with changes in the communication environment.

Diagram explaining the heterogeneous environment Configuration diagram of wireless communication system Configuration diagram of a wireless communication system according to another example Configuration diagram of transport processing unit Configuration example of packet header Configuration example of communication method database Flow chart for explaining the operation of the integrated management function unit Image of the case where the integrated management function unit performs retransmission processing by UDP A configuration diagram and a sequence diagram of a wireless communication system according to a first embodiment A configuration diagram and a sequence diagram of a wireless communication system according to a second embodiment A configuration diagram and a sequence diagram of a wireless communication system according to a third embodiment

  A communication system according to an embodiment of the present invention will be described with reference to the drawings. 2 and 3 are system configuration diagrams of the communication system according to the present embodiment.

  The communication system according to the present embodiment includes, as shown in FIG. 2, a terminal 100 compatible with a plurality of communication methods, a plurality of access functions 200 for accommodating the terminal 100 in each communication method, and each communication method. A plurality of packet core networks 300, an IP service network 400 connected to each packet core network 300, and a server 500 that is a communication counterpart with the terminal 100 and connected to the IP service network 400 are provided. As another modification, as shown in FIG. 3, a configuration in which the terminal 100 communicates with the server 500 via the proxy 600 can be considered.

  The feature of the present invention resides in the function of the transport layer processing unit 700 of the OSI reference model, which terminates the transport layer connection between the terminal 100 and the server 500 or the proxy 600, as described later. The transport layer processing unit 700 is mounted on the terminal 100 and the server 500 in the configuration example of FIG. 2, and on the IP service network 400 side of the terminal 100 and the proxy 600 (terminal 100 side) in the configuration example of FIG. 3. Implemented in The use of the proxy 600 is advantageous in that the present invention can be implemented without the server 500 being modified or changed.

  The configuration of the access function 200, the packet core network 300, the IP service network 400, and the overall configuration of each device are well known. Examples of the plurality of communication methods include LTE, Wi-Fi, wired Ethernet (registered trademark), and the like. The plurality of access functions 200 correspond to the respective communication methods, and, for example, in the case of LTE, each device such as an eNodeB that configures E-UTRAN (Evolved Universal Terrestrial Radio Access Network), which is a network of a radio section. Is included. The plurality of packet core networks 300 also correspond to the respective communication methods, and are, for example, EPC (Evolved Packet Core) in the case of LTE. It should be noted that one packet core network 300 may accommodate a plurality of access functions 200 with different or the same communication scheme (for example, in the case where carrier aggregation or dual connectivity is applied).

  As shown in FIGS. 2 and 3, the transport layer processing unit 700 divides the transport layer processing unit 700 located at both ends of communication in the transport layer of the OSI reference model into an upper layer and a lower layer, A plurality of transport protocol processing units 800 are arranged in parallel in the layer, and an integrated management function unit 900 that integrates and manages the plurality of transport protocol processing units 800 is arranged in the upper layer. The basic configuration of the transport layer processing unit 700 is common to the terminal 100, the server 500, and the proxy 600. Further, in the terminal 100, the server 500, and the proxy 600, the configuration of layers other than the transport layer of the OSI reference model is arbitrary, and a conventionally known configuration can be adopted.

  The configuration of the transport layer processing unit 700 will be described with reference to FIG. The integrated management function unit 900, which is an upper layer of the transport layer processing unit 700, has a function of managing a plurality of different transport protocols and dynamically switching the transport protocol suitable for the communication environment. For example, there is a method of determining a protocol that matches the characteristics, which is registered in a database. Further, the integrated management function unit 900 has a function of dividing the flow in the transport layer and enabling use of a plurality of different networks. Here, the divided flows can be assigned different protocols. Further, the integrated management function unit 900 has a mechanism capable of ensuring continuity between different protocols. Specifically, it has a function of assigning a common sequence number, a subsequence number for each subflow, and a function of notifying a packet transmission rate such as a congestion window size in TCP. Negotiation of communication method change is performed in the protocol header. In addition, the integrated management function unit 900 has a function of performing control of retransmitting a protocol having no retransmission control such as UDP by another protocol such as TCP in the transport layer.

  An implementation example of the above functions is shown in FIG. As shown in FIG. 4, the integrated management function unit 900 uses a communication environment monitoring unit 910 that detects a change in the communication environment, a communication scheme selection unit 920 that selects a protocol suitable for the changed environment, and a plurality of RATs. When using a subflow control unit 930 that adds and deletes subflows, a sequence number management unit 940 that assigns a common sequence number when using multiple flows, and a protocol that does not have retransmission control such as UDP. A retransmission control unit 950 that performs retransmission control, a communication method database 960 that associates a communication environment with a communication method, a transmission buffer 970, and a reception buffer 980 are provided. As described later, according to the embodiment of the present communication system, the communication method database 960 may be provided only on the terminal 100 side or the server 500 or the proxy 600 side.

  The plurality of transport protocol processing units 800 disposed in the lower layer of the integrated management function unit 900 can use any protocol and its options including those known in the prior art. For example, TCP, UDP, SCTP (Stream Control Transmission) in addition to TCP in various forms such as TCP Reno, CUBIC, High Speed TCP, FAST TCP, or any other congestion control algorithm such as Quick-Start, MPTCP, SACK (Selective Acknowledgment) etc. Transport protocols other than TCP, such as Protocol) and QUIC (Quick UDP Internet Connections), may be mentioned. Here, as described above, since the integrated management function unit 900 includes the retransmission control unit 950, a protocol that does not have retransmission control such as UDP can also be implemented as the transport protocol processing unit 800.

  The method of changing the communication method by the integrated management function unit 900 will be described in detail. Here, changing the communication method does not only mean switching from one transport protocol processor 800 to another transport protocol processor 800, but also during communication using a certain transport protocol processor 800. It also includes adding the flow of another transport protocol processor 800. That is, the fact that the use status of the transport protocol processor 800 differs before and after a certain point in time means "change of communication method". In the following description, when a flow is added, the additional flow is called a subflow.

  In the present invention, detection of a change in the communication environment by the communication environment monitoring unit 910 uses an existing method. Sensing on the receiving side or acquiring information on the transmitting side from the base station of the access function 200 may be considered.

  The change of the communication mode may be determined by the communication mode selection unit 920 on the transmission side or the communication mode selection unit 920 on the reception side may request the communication mode.

  A method of performing notification of a communication method, a request, negotiation, and the like by using an option area of a protocol header in each transport protocol processing unit 800 and a method of using a header dedicated to the integrated management function of the present application can be considered. When using the option area of each protocol header, it is necessary to extend the header if there is no option area such as UDP. An example of the configuration of the header is shown in FIG. The type number includes a number for identifying how to use the option area at the time of negotiation, packet transfer, etc. At the time of negotiation, notification of a transmission / reception IP address, a use RAT, a use protocol, etc. is performed, and at the time of packet transfer, a subsequence number is managed.

  As a method of determining the communication method by the communication method selection unit 920, for example, there is a method of using a communication method database 960 which associates a communication environment with a protocol. A configuration example of the communication method database 960 is shown in FIG.

  When the integrated management function unit 900 of the transmission side (the server 500 or proxy 600 for downloading and the terminal 100 for uploading) selects the communication method, the processing of FIG. 7 is performed.

  That is, as shown in FIG. 7, when the integrated management function unit 900 monitors the communication environment such as the status of the available RAT by the communication environment monitoring unit 910 and detects a change in the communication environment (step S1), the communication method The database 960 is referenced (step S2). Then, the communication method selection unit 920 determines whether or not to change the communication method (step S3), and if there is no change, the original communication is continued (step S4). On the other hand, when there is a change, when using the subflow (step S5), the flow addition negotiation process is performed (step S6), the sequence number management unit 940 performs sequence allocation (step S7), and the communication method is changed. (Step S8). Even when the subflow is not used, the communication method is changed (step S9).

  When the communication method is selected by the integrated management function unit 900 on the reception side, the integrated management function unit 900 on the reception side requests the communication method change to the integrated management function unit 900 on the transmission side instead of changing the communication method in FIG. . If the integrated management function unit 900 on the transmission side approves, the system is changed and communication is performed.

  Next, a method of securing continuity between different protocols by the integrated management function unit 900 will be described in detail.

  In order to secure the continuity of communication even when switching between different protocols, the integrated management function unit 900 uses the protocol header to perform the following.

・ Sequence number common to all protocols and subsequence number allocation for each subflow ・ Negotiation of flow addition / deletion and protocol change ・ Handover to communication method after changing currently set parameters such as packet transmission rate ・ No retransmission control Confirmation of arrival when using protocol

  Further, a function of complementing a protocol such as UDP without retransmission by TCP or the like by the integrated management function unit 900 will be described in detail.

  Since the order of arrival of packets is not guaranteed in UDP, a reception buffer 980 is provided in the integrated management function unit 900, and the retransmission control unit 950 performs packet alignment and acknowledgment of arrival. The arrival confirmation response is performed using highly reliable TCP or the like, and the confirmation frequency is changed according to the buffer capacity. When TCP and UDP are used in combination, it is possible to improve efficiency by performing UDP acknowledgment using TCP ACK packets. FIG. 8 shows an image of retransmission in the case where the terminal 100 and the proxy 600 are provided with the integrated management function unit 900.

  A first embodiment of the present invention will be described with reference to FIG. A present Example is an example in the case of determining a communication system by the server or proxy side of an other provider network. Here, a case where the terminal 100 and the proxy 600 communicate with each other and a packet is transmitted from the proxy 600 to the terminal 100 will be described as an example.

  As shown in FIG. 9, it is assumed that RAT1 and RAT2 which are access functions 200 are accommodated in different packet core networks 300, respectively. Here, the cell of RAT1 is wide but the communication band is narrow, and the cell of RAT2 is narrower than RAT1 and included in the cell of RAT1, and the communication band is wider than RAT1. The terminal 100 and the proxy 600 have an integrated management function unit 900. In this example, the communication method database 960 of the integrated management function unit 900 of the proxy 600 is referred to.

  If the integrated management function unit 900 of the terminal 100 detects the RAT2 of the broadband cell (step S3), during communication by the TCP1 via the RAT1 of the macro cell between the terminal 100 and the proxy 600 (steps S1 and S2) The integrated management function unit 900 of 100 notifies that to the integrated management function unit 900 of the proxy 600 (step S4), and the integrated management function unit 900 of the proxy 600 refers to the communication method database 960 (step S5). During communication between the terminal 100 and the proxy 600 or at the start of communication, it is confirmed in advance that both can use the integrated management function unit 900 (step S2).

  Then, if the integrated management function unit 900 of the proxy 600 selects a communication method by TCP1 in RAT1 and a communication method by UDP in RAT2, for example, it negotiates a method change (step S6). Specifically, the integrated management function unit 900 of the proxy 600 generates a subflow and distributes the sequence, and notifies the terminal 100 of a communication method to be used. Then, the integrated management function unit 900 of the terminal 100 performs port release and connection establishment if a new communication method can be used. At this time, connection establishment can be shortened by performing negotiation such as acquisition of a cookie in communication by RAT1 in advance.

  As a method of distributing a sequence, a method of simply allocating continuous packets of sequence numbers, a method of forming blocks for every several packets, and allocating to flows for each block can be considered.

  The subsequent transmission packets are transmitted by the flow by UDP via RAT2 and the flow by TCP1 via RAT1 (steps S7 to S9). Here, since UDP does not perform retransmission control, TCP1 and UDP flow are acknowledged with an ACK packet of TCP1 via RAT1 (step S10), and if necessary, packets are resent by TCP1 via RAT1. (Step S11).

  A second embodiment of the present invention will be described with reference to FIG. A present Example is an example in the case of determining a communication system by the terminal side of an other carrier network. Here, a case where the terminal 100 and the proxy 600 communicate with each other and a packet is transmitted from the proxy 600 to the terminal 100 will be described as an example.

  As shown in FIG. 10, it is assumed that RAT1 and RAT2 that are access functions 200 are accommodated in different packet core networks 300, respectively. Here, the cell of RAT1 is wide but the communication band is narrow, and the cell of RAT2 is narrower than RAT1 and included in the cell of RAT1, and the communication band is wider than RAT1. The terminal 100 and the proxy 600 have an integrated management function unit 900. In this example, the communication method database 960 of the integrated management function unit 900 of the terminal 100 is referred to.

  If the integrated management function unit 900 of the terminal 100 detects the RAT2 of the broadband cell (step S23), during communication by the TCP1 via the RAT1 of the macro cell between the terminal 100 and the proxy 600 (steps S21 and S22) The integrated management function unit 900 of 100 references the communication method database 960 (step S24). During communication between the terminal 100 and the proxy 600 or at the start of communication, it is confirmed in advance that both can use the integrated management function unit 900 (step S22).

  The integrated management function unit 900 of the terminal 100 notifies the integrated management function unit 900 of the proxy 600 of a request for changing the communication method, for example, when selecting the communication method by TCP1 in RAT1 and the communication method by UDP in RAT2 (step S25) . The integrated management function unit 900 of the proxy 600 confirms that the communication system can be changed (step S26), and approves the communication system change to the integrated management function unit 900 of the terminal 100 (step S27).

  The subsequent transmission packets are transmitted by the flow by UDP via RAT2 and the flow by TCP1 via RAT1 (steps S28 to S30). Here, since UDP does not perform retransmission control, TCP1 and UDP flow are acknowledged with an ACK packet of TCP1 via RAT1 (step S31), and if necessary, packets are retransmitted by TCP1 via RAT1. (Step S32).

  A third embodiment of the present invention will be described with reference to FIG. The present embodiment is an example in the case of performing CA (carrier aggregation) and DC (dual connectivity) in the same carrier network. That is, this is an example in which the present invention is applied in the case where a plurality of access functions 200 are accommodated in the same packet core network 300 and an environment in which traffic is integrated using the plurality of access functions 200 has already been constructed.

  As described above, in the case of CA / DC, even if the flow is divided by the integrated management function unit 900, radio resources are allocated in the packet data convergence protocol (PDCP) layer of the base station in the access function 200. Therefore, when the flow is divided in consideration of the characteristics of the base station, it is necessary to route the flow in cooperation with the PDCP layer. Even in the case of CA and DC, it is possible to improve QoS (Quality of Service) by detecting changes in bandwidth and error rate and selecting a protocol.

  FIG. 11 shows a sequence for changing from TCP1 to TCP2. As shown in FIG. 11, during communication by TCP1 between the terminal 100 and the proxy 600 via the RAT1 of the macro cell (steps S41 and S42), the integrated management function unit 900 of the terminal 100 adds a band for the communication. If it detects (step S43), the communication system database 960 will be referred to (step S44). During communication between the terminal 100 and the proxy 600 or at the start of communication, it is confirmed in advance that both can use the integrated management function unit 900 (step S42).

  The integrated management function unit 900 of the terminal 100 notifies the integrated management function unit 900 of the proxy 600 of a change request of the communication method from TCP1 to TCP2 (step S45). The integrated management function unit 900 of the proxy 600 confirms that the communication system can be changed (step S46), and approves the communication system change to the integrated management function unit 900 of the terminal 100 (step S47).

  The subsequent transmission packets are transmitted by the flow of TCP 2 (steps S 48 and S 49).

  As described above, according to the communication system according to the present embodiment, when a change in the communication environment such as the RAT is detected, switching to a transport protocol suitable for the environment results in a short time in the case of ultra-wide band. It is possible to control to maximize the QoS under each environment, such as maximizing throughput in the case and not unnecessarily reducing throughput when the high error rate is reached. By being able to use the ultra-wide band in a short time, it is possible to realize downloading of large-capacity files using small cells even while moving. Communication traffic can be distributed by effectively using small cells, and congestion of license bands such as LTE can be avoided. In addition, by using a plurality of RATs together, stable communication can be maintained even in a heterogeneous environment where the redundancy is high and cell switching frequently occurs when moving.

Furthermore, since control of protocol switching is performed in the transport layer, it is not necessary for the application side to perform control in response to changes in the communication environment.
As mentioned above, although embodiment of this invention and its Example were explained in full detail, this invention is not limited to this. For example, the transport protocol listed in the above embodiment is an example, and the present invention can be practiced with other transport protocols. Further, for example, a method of detecting a change in communication environment, a data structure of a communication method database, and the like are not limited to the above embodiment.

  In the above embodiment, the wireless access function is mainly illustrated for the access function 200, but the form of the packet core network 300 connected to the access function 200 and the access function 200 is not limited, and for example, a wired access function such as an optical fiber The present invention can be practiced even if there is a mixture of

100 terminal 200 access function 300 packet core network 400 IP service network 500 server 600 proxy 700 transport layer processing unit 800 transport protocol processing unit 900 integrated management function unit 910 communication environment monitoring unit 920 ... Communication method selection unit 930 ... Sub flow control unit 940 ... Sequence number management unit 950 ... Retransmission control unit 960 ... Communication method database 970 ... Transmission buffer 970
980 ... reception buffer 980

Claims (7)

In a communication apparatus that transmits and receives packets,
The transport layer of the OSI 7 hierarchical model is divided into upper and lower layers, a plurality of transport protocol processing units are arranged in the lower layer, and the communication by the plurality of transport protocol processing units is integrated and managed in the upper layer. Integrated management function unit,
The integrated management function unit is a communication environment monitoring unit that monitors the communication environment of communication by the transport protocol processing unit, and one or more suitable for the communication environment that has changed when the communication environment monitoring unit detects a change in the communication environment. When selecting a transport protocol processor and switching to communication by the selected one or more transport protocol processors, and when the communication scheme selector switches to communication by a plurality of transport protocol processors A communication apparatus comprising: a sequence number management unit for assigning a common sequence number to packets related to a flow by each transport protocol processing unit . In a communication apparatus that transmits and receives packets,
The transport layer of the OSI 7 hierarchical model is divided into upper and lower layers, a plurality of transport protocol processing units are arranged in the lower layer, and the communication by the plurality of transport protocol processing units is integrated and managed in the upper layer. Integrated management function unit,
The integrated management function unit is a communication environment monitoring unit that monitors the communication environment of communication by the transport protocol processing unit, and one or more suitable for the communication environment that has changed when the communication environment monitoring unit detects a change in the communication environment. A communication method selection unit that selects a transport protocol processing unit and switches to communication by the selected one or more transport protocol processing units, and the communication method selection unit performs communication from the first transport protocol processing unit according to the first and the second A sub-flow adding unit for adding a sub-flow by the second transport protocol processing unit to a flow by the existing first transport protocol processing unit when switching to communication by the second transport protocol processing unit A communication device characterized by In a communication apparatus that transmits and receives packets,
The transport layer of the OSI 7 hierarchical model is divided into upper and lower layers, a plurality of transport protocol processing units are arranged in the lower layer, and the communication by the plurality of transport protocol processing units is integrated and managed in the upper layer. Integrated management function unit,
The integrated management function unit is a communication environment monitoring unit that monitors the communication environment of communication by the transport protocol processing unit, and one or more suitable for the communication environment that has changed when the communication environment monitoring unit detects a change in the communication environment. A communication method selection unit which selects a transport protocol processing unit and switches to communication by one or more selected transport protocol processing units, and a first transport protocol processing unit selected by the communication method selection unit performs retransmission control And a retransmission control unit for performing retransmission control of packets in the first transport protocol processing unit using a communication path related to the second transport protocol processing unit when not having the communication control unit. . The integrated management function unit includes a communication method storage unit that stores information in which a communication environment and a transport protocol processing unit are associated with each other.
The communication apparatus according to any one of claims 1 to 3, wherein the communication scheme selection unit selects one or more transport protocol processing units based on the related information stored in the communication scheme storage unit. . A communication control method in a communication apparatus for transmitting and receiving packets, comprising:
The transport layer of the OSI 7 hierarchical model is divided into upper and lower layers, a plurality of transport protocol processing units are arranged in the lower layer, and the communication by the plurality of transport protocol processing units is integrated and managed in the upper layer. Provide integrated management functions,
The communication environment monitoring unit of the integrated management function unit monitors the communication environment of communication by the transport protocol processing unit;
When the communication system selection unit of the integrated management function unit detects a change in the communication environment by the communication environment monitoring unit, one or more selected and selected one or more transport protocol processing units suitable for the changed communication environment switch to communication by the transport protocol processing unit,
The sequence number management unit of the integrated management function unit assigns a common sequence number to a packet related to a flow of each transport protocol processing unit when the communication scheme selection unit switches to communication by a plurality of transport protocol processing units. A communication control method in a communication apparatus characterized in that. The program for operating a computer as an integrated management function part in any one of Claims 1-4 . A communication system comprising: a terminal that transmits and receives packets; a network that accommodates the terminal using an access function; and a communication device that is a communication partner in the transport layer of the terminal.
The terminal and communication device
The transport layer of the OSI 7 hierarchical model is divided into upper and lower layers, a plurality of transport protocol processing units are arranged in the lower layer, and the communication by the plurality of transport protocol processing units is integrated and managed in the upper layer. Integrated management function unit,
The integrated management function unit is a communication environment monitoring unit that monitors the communication environment of communication by the transport protocol processing unit, and one or more suitable for the communication environment that has changed when the communication environment monitoring unit detects a change in the communication environment. When selecting a transport protocol processor and switching to communication by the selected one or more transport protocol processors, and when the communication scheme selector switches to communication by a plurality of transport protocol processors A communication system, comprising: a sequence number management unit for assigning a common sequence number to packets related to a flow by each transport protocol processing unit .

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