WO2013069193A1

WO2013069193A1 - Mobile communication terminal, communication method, communication system, and control apparatus

Info

Publication number: WO2013069193A1
Application number: PCT/JP2012/006222
Authority: WO
Inventors: Ippei Akiyoshi; Yasuhiro Mizukoshi; Nobuhiko Itoh
Original assignee: Nec Corporation
Priority date: 2011-11-09
Filing date: 2012-09-28
Publication date: 2013-05-16

Abstract

A communication system comprises: a control apparatus that controls packet forwarding; and a mobile communication terminal that communicates with a network including the control apparatus. The mobile communication terminal comprises: a plurality of communication interfaces for wireless communication; a processing means that processes a packet in accordance with an instruction from the control apparatus; and a control means that transmits to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information. The control apparatus can control a mobile communication terminal, giving consideration to communication quality of communication interfaces of the mobile communication terminal.

Description

MOBILE COMMUNICATION TERMINAL, COMMUNICATION METHOD, COMMUNICATION SYSTEM, AND CONTROL APPARATUS

Field

(CROSS-REFERENCE TO RELATED APPLICATIONS)
The present invention is based upon and claims the benefit of the priority of Japanese patent application No. 2011-245300, filed on November 9, 2011, the disclosure of which is incorporated herein in its entirety by reference thereto.
The present invention relates to a mobile communication terminal, a communication method, a communication system, and a control apparatus, and more particularly to communication technology in which the control apparatus controls packet processing of the mobile communication terminal.

Background

Recently, centrally controlled network architecture has been proposed. Technology known as OpenFlow is an example of centrally controlled network architecture (PTL 1 and NPLs 1 and 2). In OpenFlow communication is taken as end-to-end flows, and path control, failure recovery, load balancing, and optimization are performed on a per-flow basis. An OpenFlow switch as specified in NPL 2 has a secure channel for communication with an OpenFlow controller positioned in a control apparatus, and operates according to a flow table to which information is added and whose contents are rewritten according to an instruction from the OpenFlow controller, as necessary. In the flow table, a set of the following is defined for each flow: matching rule (Header fields) against which a packet header is matched, flow statistical information (Counters), and actions (Actions) that define processing content (see FIG. 13).

For example, when a packet is received, the OpenFlow switch searches the flow table for an entry that has a matching rule (refer to the header fields in FIG. 13) matching header information of the received packet. If an entry matching the received packet is found as a result of the search, the OpenFlow switch updates the flow statistical information (Counter) and also implements processing content (packet transmission from a specified port, flooding, dropping, and the like) described in an Actions field of the entry in question, for the received packet. On the other hand, if an entry matching the received packet is not found as a result of the search, the OpenFlow switch forwards the received packet to the OpenFlow controller via a secure channel, requests determination of a path of the packet based on transmission source and destination of the received packet, receives a flow entry realizing this, and updates the flow table. In this way, the OpenFlow switch uses the entry stored in the flow table as a processing rule to perform packet forwarding.

PCT International Publication No. 2008/095010

Nick McKeown and seven other authors, "OpenFlow: Enabling Innovation in Campus Networks," [online], [search conducted on November 9, 2011], the Internet: <URL:http://www.openflowswitch.org//documents/openflow-wp-latest.pdf> "Openflow Switch Specification, Version 1.1.0 Implemented (Wire Protocol 0x02)," February 28, 2011, [online], [search conducted on November 9, 2011], the Internet: <URL: http://www.openflowswitch.org/documents/openflow-spec-v1.1.0.pdf>

Summary

The disclosures of PTL 1 and

NPLs

1 and 2 given above are hereby incorporated herein in their entirety by reference thereto. The following analysis is given according to the present disclosure.

With regard to the abovementioned related art, in centrally controlled network architecture, an object controlled by a controller (control apparatus) is a switch or a router only, and there is no disclosure whatsoever of controlling a mobile communication terminal.

Moreover, the control apparatus cannot comprehend the communication quality of a communication interface of the mobile communication terminal.

Accordingly, there is a need in the art to provide a mobile communication terminal, a communication method, a communication system, and a control apparatus that contributes to enabling the control apparatus to control the mobile communication terminal, giving consideration to communication quality of a communication interface of the mobile communication terminal.

According to a first aspect of the present disclosure there is provided a mobile communication terminal that communicates with a network including a control apparatus that controls packet forwarding, the mobile communication terminal comprising:
a plurality of communication interfaces for wireless communication;
a processing means (unit) that processes a packet in accordance with an instruction from the control apparatus; and
a control means (unit) that transmits to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information.

According to a second aspect of the present disclosure there is provided a communication method by a mobile communication terminal that communicates with a network including a control apparatus that controls packet forwarding and includes a plurality of communication interfaces for wireless communication, the method comprising:
processing a packet in accordance with an instruction from the control apparatus; and
transmitting to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information.

According to a third aspect of the present disclosure there is provided a communication system, comprising:
a control apparatus that controls packet forwarding; and
a mobile communication terminal that communicates with a network including the control apparatus, wherein
the mobile communication terminal comprises:
a plurality of communication interfaces for wireless communication;
a processing means (unit) that processes a packet in accordance with an instruction from the control apparatus; and
a control means (unit) that transmits to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information.

According to a fourth aspect of the present disclosure there is provided a control apparatus that controls packet forwarding, the control apparatus comprising:
a means (unit) that receives, from a mobile communication terminal that includes a plurality of communication interfaces for wireless communication and processes a packet in accordance with an instruction from the control apparatus, communication quality information representing communication quality of each of the plurality of communication interfaces; and
a means (unit) that transmits to the mobile communication terminal an instruction determined based on the communication quality information.
According to a fifth aspect of the present disclosure there is provided a mobile communication terminal that communicates with a network including a control apparatus that controls packet forwarding, the mobile communication terminal comprising:
a plurality of communication interfaces for wireless communication; and
a means (unit) that downloads a program, wherein
the program causes the mobile communication terminal to execute:
processing of a packet in accordance with an instruction from the control apparatus; and
transmitting to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information.

According to the mobile communication terminal, the communication method, the communication system, and the control apparatus related to the present disclosure, the control apparatus can control the mobile communication terminal, giving consideration to communication quality of communication interfaces of the mobile communication terminal.

FIG. 1 is a diagram showing an example of a connection configuration of a communication system according to the present disclosure. FIG. 2 is a block diagram showing an example of a configuration of a mobile communication terminal according to the present disclosure. FIG. 3 is a block diagram showing an example of a configuration of a mobile communication terminal of a communication system according to a first exemplary embodiment. FIG. 4 is a block diagram showing an example of a configuration of a packet forwarding function unit in the mobile communication terminal of the communication system according to the first exemplary embodiment. FIG. 5 is a table showing an example of a configuration of an instruction received by the mobile communication terminal from a control apparatus in the communication system according to the first exemplary embodiment. FIG. 6 is a table showing an example of information managed by an access management DB in the communication system according to the first exemplary embodiment. FIG. 7 is a block diagram showing an example of a configuration of the control apparatus in the communication system according to the first exemplary embodiment. FIG. 8 is a table showing an example of information described in a packet when an instruction request is received from the mobile communication terminal, in the communication system according to the first exemplary embodiment. FIGS. 9(a)-(c) are table showing respective examples of access schemes and electric field strengths, in the communication system according to the first exemplary embodiment. FIG. 10 is a sequence diagram showing an example of an operation of the communication system according to the first exemplary embodiment. FIG. 11 is a table showing an example of information related to the mobile communication terminal managed by the control apparatus, in the communication system according to the first exemplary embodiment. FIG. 12 is a sequence diagram showing an example of an operation of a communication system according to a second exemplary embodiment. FIG. 13 is a diagram showing an example of a flow table in related technology.

Modes

First, a description is given of an overview of the present disclosure.

FIG. 1 is a diagram showing an example of a connection configuration of a communication system according to the present disclosure. The system configuration of FIG. 1 is an example, and the present invention is not limited to the system configuration described in FIG. 1.

A mobile communication terminal 1 supports a plurality of types of RAT (Radio Access Technology), and communicates via RANs (Radio Access Network) corresponding to respective RATs. A RAN is, for example, a W-CDMA (Wideband Code Division Multiple Access) network 6 or an 802.11g network 7. Note that the RAN is not limited to what is shown in FIG. 1. The mobile communication terminal 1 is a device that has a communication function, such as a mobile telephone, a personal computer, a mobile router, or the like.

The mobile communication terminal 1 communicates with a network 4 via a RAN, for example. The mobile communication terminal 1 communicates with a server apparatus 5 via the network 4, for example.

The network 4 includes a control apparatus 2 and a plurality of packet forwarding apparatuses 3, for example. The control apparatus 2 centrally controls packet forwarding by the packet forwarding apparatuses 3. The control apparatus 2, for example, determines a packet processing method in response to a request from a packet forwarding apparatus 3, and instructs the determined processing method to the packet forwarding apparatus 3. The control apparatus 2, for example, instructs a processing method corresponding to a forwarding path to the server apparatus 5, to the packet forwarding apparatus 3. The packet forwarding apparatus 3 processes the received packet in accordance with the instruction from the control apparatus 2.

It is to be noted that the network 4 may include a communication device outside of the packet forwarding apparatus 3 that forwards packets in accordance with the control apparatus 2. For example, the network 4 may include a communication device that operates based on a distributed protocol such as RIP (Routing Information Protocol) or OSPF (Open Shortest Path First).

The mobile communication terminal 1, for example, communicates with the server apparatus 5 via the packet forwarding apparatus 3 that operates in accordance with an instruction from the control apparatus 2.

FIG. 2 is a block diagram showing an example of a configuration of the mobile communication terminal 1. The configuration of FIG. 2 is an example, and the mobile communication terminal 1 of the present invention is not limited to the configuration described in FIG. 2.

The mobile communication terminal 1 has a plurality of types of communication interface 10. Two communication interfaces 10 are shown in FIG. 2, but the number of communication interfaces 10 is not limited to two. The mobile communication terminal 1 communicates with a corresponding RAN via a communication interface 10. For example, the mobile communication terminal 1 communicates with a W-CDMA network 6 via a communication interface 10 corresponding to the W-CDMA network 6.

A packet forwarding function unit 13 executes packet forwarding and the like, in accordance with an instruction from the control apparatus 2 in the network 4. The packet forwarding function unit 13 may, for example, be a virtual switch built in software. The packet forwarding function unit 13 includes a processing unit 11 and a control unit 12.

The control unit 12 controls communication with the control apparatus 2. The control unit 12, for example, establishes a control channel with the control apparatus 2, in order for the packet forwarding function unit 13 to receive an instruction from the control apparatus 2. The control unit 12, for example, makes a request for an instruction to the control apparatus 2, via the established control channel.

The processing unit 11 processes packets in accordance with an instruction received by the control unit 12 from the control apparatus 2. The processing unit 11, for example, forwards packets to one of the communication interfaces 10. In addition, the processing unit 11, for example, forwards a packet received via one of the communication interfaces 10 to a prescribed application operated by the mobile communication terminal 1.

The control unit 12 transmits communication quality information of the respective communication interfaces 10 to the network 4, in order to notify the control apparatus 2 of the communication quality information. The communication quality information, for example, is electric field strength of the communication interfaces 10. The communication quality information, for example, is sent to the control apparatus 2, via the packet forwarding apparatus 3. Furthermore, the communication quality information, for example, is sent to the control apparatus 2, via the abovementioned control channel.

Since the mobile communication terminal 1 transmits the communication quality information of the communication interfaces 10, the control apparatus 2 can give an instruction to the mobile communication terminal 1, giving consideration to the communication quality information received. For example, the control apparatus 2 selects a communication interface 10 to be used by the mobile communication terminal 1, based on the communication quality information received. The control apparatus 2 sends an instruction to the mobile communication terminal 1 so that the mobile communication terminal 1 uses the selected communication interface 10 to communicate. The mobile communication terminal 1 transmits/receives packets from a corresponding communication interface 10, based on the received instruction.

As described above, according to the present disclosure, the control apparatus 2 can control the mobile communication terminal 1, giving consideration to communication quality of the mobile communication terminal 1.

(First Exemplary Embodiment)
A description is given concerning a communication system related to a first exemplary embodiment, making reference to the drawings.

FIG. 3 is a block diagram showing an example of a configuration of a mobile communication terminal 100 in the present exemplary embodiment. Referring to FIG. 3, the mobile communication terminal is provided with N application units 101, a protocol stack unit 102, a packet forwarding function unit 103, n port units 104, and N communication interfaces 105.

The configuration described in FIG. 3 is an example, and the configuration of the mobile communication terminal 100 is not limited to the configuration described in FIG. 3. It is to be noted that the mobile communication terminal 100 belongs to the communication system described in FIG. 1. The mobile communication terminal 100 is an apparatus that has a communication function, such as a mobile telephone, a personal computer, a mobile router, or the like.

The packet forwarding function unit 103 includes a plurality of the port units 104. In the example of FIG. 3, the packet forwarding function unit 103 has n port units 104 (n is an integer). The respective communication interfaces 105, for example, are connected to at least 1 of the plurality of port units 104.

The mobile communication terminal 100 transmits an access scheme and communication quality information of a communication interface 105 that is connected to at least one of the plurality of port units 104, to a network 4, in order to give notification to a control apparatus 2. A detailed description is given below, making reference to the drawings.

FIG. 3 shows an example of a configuration of the mobile communication terminal 100.

In the mobile communication terminal 100, a plurality of applications (application units 101 #1 to #N) are operating. The applications communicate with the network 4 via a W-CDMA network 6 or an 802.11g network 7.

When an application transmits communication data to the network 4, the communication data is processed by the protocol stack unit 102 (for example, a protocol stack such as an OSI reference model), and formed into a packet to which a prescribed protocol header or the like is given. The packet is transmitted from the communication interface 105 via the packet forwarding function unit 103.

The packet forwarding function unit 103 forwards the packet from the port unit 104, in accordance with an instruction from the control apparatus 2. The packet forwarded from the port unit 104 is transmitted to the W-CDMA network 6 or the 802.11g network 7 via one of the communication interfaces 105. The packet received by the communication interface 105 from the W-CDMA network 6 or the 802.11g network 7 is sent to an application via the packet forwarding function unit 103.

FIG. 4 is a block diagram showing an example of a configuration of the packet forwarding function unit 103. Referring to FIG. 4, the packet forwarding function unit 103 comprises a control unit 130, a processing unit 131, an access management unit 132, an access management DB 133, a processing rule management unit 134, and a processing rule database (DB) 135.

The control unit 130 controls communication with the control apparatus 2. The control unit 130, for example, establishes a control channel with the control apparatus 2, in order for the packet forwarding function unit 103 to receive an instruction from the control apparatus 2. The control unit 130, for example, requests an instruction from the control apparatus 2, via the established control channel.

The control unit 130 passes the instruction received from the control apparatus 2 to the processing rule management unit 134. The processing rule management unit 134 passes the instruction received from the control apparatus 2 to the processing rule database 135.

FIG. 5 is a table showing a configuration example of an instruction received from the control apparatus 2. The control apparatus 2, for example, transmits a processing rule including a matching rule that is a condition for distinguishing a flow to which a packet belongs, and a method of processing the packet belonging to the flow matching the matching rule, to the control unit 130. That is, the control apparatus 2 transmits the processing rule as an instruction to the control unit 130. The processing rule DB 135 stores the processing rule received from the control apparatus 2.

FIG. 5 shows "flow #A" and "flow #B" as examples of matching rules. "Flow" indicates a sequence of packet groups identified by prescribed information such as packet destination address or transmission source address, or a combination of such information. For example, a condition of "a packet whose packet transmission destination address is 'A,' and whose packet transmission source is 'a'" is defined as a matching rule in "flow #A." As a further example, a condition of "a packet provided with a port number corresponding to http/https protocol (that is, a packet for Web access)" is defined as a matching rule. A packet conforming with the matching rule is processed by a processing method corresponding to that matching rule.

The processing unit 11 executes processing such as packet forwarding, rewriting of packet header unit, or the like, in accordance with an instruction of the control apparatus 2. A search unit 136 retrieves a processing rule conforming with a packet, among processing rules stored in the processing rule DB 135. The search unit 136, for example, compares packet content and matching rule, and retrieves a processing rule including a matching rule that matches the packet content. In a case where a processing rule conforming with a packet is not stored in the processing rule DB 135, for example, the search unit 136 gives notification to the control unit 130, and the control unit 130 makes a request for a processing rule with respect to the control apparatus 2.

An action execution unit 137 processes a packet in accordance with a processing method defined by the processing rule retrieved by the search unit 136. For example, the action execution unit 137 executes processing to forward a packet from a prescribed port unit 104, or processing to rewrite packet content, in accordance with the processing rule.

The access management unit 132 searches the access management DB 133, and gives notification of an access scheme or communication quality information of the communication interface 105 to the control unit 130. The control unit 130 transmits the notified access scheme or communication quality information to the network 4, in order to give notification to the control apparatus 2.

FIG. 6 is a table showing an example of information managed by the access management DB 133. The configuration described in FIG. 6 is an example, and the configuration of the access management DB 133 is not limited to the configuration described in FIG. 6. In the present exemplary embodiment, the description of FIG. 6 is in a form where information of port number, IF identifier, communication quality information, link status, and access scheme, is stored in the access management DB 133, but all of the abovementioned information need not necessarily be stored. For example, with regard to the mobile communication terminal 100, dynamic information that varies moment by moment, that is, communication quality information (electric field strength), may be calculated whenever a new packet is received, and other information (port number, IF identifier, link status, access scheme) only may be managed by the access management DB 133. On the other hand, the mobile communication terminal 100 may calculate all the information, whenever a packet is received.

The access management DB 133 manages interaction between the respective port units 104 and the respective communication interfaces 105, and communication quality of interfaces thereof. The access management DB 133, for example, uses the number of a port unit 104 and the number of a communication interface 105 to manage interaction of the port unit 104 and the communication interface 105. For example, a port unit 104 having the number "#1" interacts with a communication interface 105 having the number "#1." The access management DB 133 manages the communication quality, the access scheme, and the like, of the communication interface 105. For example, FIG. 6 shows that for communication quality where the number is "#1," the electric field strength is 100 dBm. In the present exemplary embodiment the access management DB 133 manages the electric field strength, for example, as communication quality. The access management DB 133 also manages link status of the communication interface 105. For example, FIG. 6 shows that the communication interface having the number "#1" has an Up status, that is, a status where a connection relationship with RAT is established.

The communication quality of the access management DB 133 represents, for example, the present communication quality of the communication interface 105. The communication quality of the communication interface 105 varies as the mobile communication terminal 100 moves, for example. The access management DB 133, for example, holds the latest information (that is, the present communication quality) of the communication quality that varies. The access management unit 132, for example, makes reference to the access management DB 133, to notify the control unit 130 of the present communication quality. It is to be noted that the communication quality is not limited to dynamically varying information.

The access management unit 132 transmits the communication quality information so that the control apparatus 2 can obtain the newest possible communication quality information. For example, the access management unit 132 transmits communication quality information at timing at which the control unit 130 makes a request for an instruction to the control apparatus 2. Furthermore, the access management unit 132 may transmit communication quality information at timing at which the amount of variation of the communication quality information exceeds a prescribed threshold.

The control unit 130, for example, gives notification of the communication quality information of the communication interface 105, together with the access scheme and port number of the port unit 104 corresponding to the relevant communication interface 105, to the control apparatus 2. Furthermore, the control unit 130, for example, gives notification of the link status of the communication interface 105, as a port status of the port unit 104 corresponding to the relevant communication interface 105, to the control apparatus 2.

The mobile communication terminal 100 may be provided with a function to download a software module having a function equivalent to the packet forwarding function unit 103. In this case, the mobile communication terminal 100 may use the downloaded software module as the packet forwarding function unit 103.

It is to be noted that the packet forwarding apparatus 3 is provided with a configuration equivalent to the packet forwarding function unit 103, outside of the access management unit 132 and the access management DB 133.

FIG. 7 is a block diagram showing an example of a configuration of the control apparatus 2. Referring to FIG. 7, the control apparatus 2 comprises a node communication unit 20, a control message processing unit 21, a calculation unit 22, a DB management unit 23, a topology management unit 24, a location management unit 25, a processing rule DB 26, a terminal information management unit 27, and an access network selection unit 28. It is to be noted that the configuration in FIG. 7 is an example, and the configuration of the control apparatus 2 is not limited to the configuration described in FIG. 7.

The processing rule DB 26 stores processing rules for setting in the mobile communication terminal 100 and the packet forwarding apparatus 3. It is to be noted that since details of the processing rules are described with reference to FIG. 5, they are omitted here.

The node communication unit 20 communicates with the mobile communication terminal 100 and the packet forwarding apparatus 3.

The topology management unit 24 manages network topology based on a connection relationship with the packet forwarding apparatus 3 collected via the node communication unit 20.

The calculation unit 22 determines a packet forwarding path based on the network topology and packet processing to be executed in the packet forwarding apparatus 3 in the forwarding path in question. That is, the calculation unit 22 calculates the packet forwarding path and determines a forwarding rule corresponding to this forwarding path.

The DB management unit 23 records the processing rule determined by the calculation unit 22 in the processing rule DB 26. The DB management unit 23 updates processing rules recorded in the processing rule DB 26, in response to notification of removal of a processing rule from the packet forwarding apparatus 3 or the mobile communication terminal 100.

The control message processing unit 21 analyzes a control message received from the packet forwarding apparatus 3 or the mobile communication terminal 100, and performs required processing. The control message processing unit 21 generates a message (for example, a message for setting a processing rule, or the like) to be transmitted to the packet forwarding apparatus 3 or the mobile communication terminal 100.

Since the control apparatus 2 is used in controlling the packet forwarding apparatus 3 or the mobile communication terminal 100, the control message processing unit 21 requests features (number of ports, execution performance for prescribed packet processing, transmission rate for each port, and the like) of the packet forwarding apparatus 3 or the mobile communication terminal 100, with respect to the packet forwarding apparatus 3 or the mobile communication terminal 100. The packet forwarding apparatus 3 or the mobile communication terminal 100 uses a Feature Reply with respect to the Feature Request, to respond with information of the number of ports for packet forwarding or the execution performance for prescribed packet processing. It is to be noted that the access management unit 132 of the mobile communication terminal 100 may respond with a Feature Reply including communication quality information, access scheme and the like, with regard to the Feature Request transmitted from the control apparatus 2.

The location management unit 25 manages the location of the mobile communication terminal 100 in the network topology of the network 4. The location management unit 25, for example, manages the location of the mobile communication terminal 100 from the IP address of the mobile communication terminal 100 extracted from a RAN such as the W-CDMA network 6 or the 802.11g network 7.

The terminal information management unit 27 manages information transmitted from the mobile communication terminal 100 or the packet forwarding apparatus 3. For example, the terminal information management unit 27 manages information (the number of ports of the packet forwarding apparatus 3, the execution performance for specific packet processing, or the like) related to performance for the packet forwarding apparatus 3, received from the packet forwarding apparatus 3. Furthermore the terminal information management unit 27 manages information received from the mobile communication terminal 100. The terminal information management unit 27 manages the communication interface 105 of the mobile communication terminal 100 and the port number of the port unit 104 corresponding to the communication interface in question.

The access network selection unit 28 selects an access network to be used by the mobile communication terminal 100 (that is, a communication interface to be used), based on the access scheme or communication quality information stored in an instruction request packet received from the control unit 130. Furthermore, for example, the access network selection unit 28 determines a priority for an access network to be used by the mobile communication terminal 100 (that is, a communication interface to be used), based on the access scheme or communication quality information stored in an instruction request packet received from the control unit 130.

The calculation unit 22 determines a processing rule corresponding to the access network to be used by the mobile communication terminal 100 (that is, the communication interface to be used), for each type of packet flow. For example, the calculation unit 22 generates a processing rule specifying that a packet belonging to a flow corresponding to video streaming is transmitted/received from a communication interface for which communication quality is good. The processing rule generated by the calculation unit 22 is transmitted to the mobile communication terminal 100, via the node communication unit 20.

A description is giving of functions of the access network selection unit 28, making reference to FIG. 8 and FIGS. 9(a)-9(c). The access network selection unit 28 described in FIG. 8 and FIGS. 9(a)-9(c) are example, and the management information of the access network selection unit 28 is not limited to the description of FIG. 8 and FIGS. 9(a)-9(c).

FIG. 8 shows information described in a packet when an instruction request is received from the control unit 130.

FIGS. 9(a) to 9(c) show information managed by the access network selection unit 28, and include tables related to each of access schemes and electric field strengths. The table related to the access scheme shown in FIG. 9(a) holds the access schemes and values corresponding to the access schemes. The tables relating to electric field strengths shown in FIG. 9(b) and 9(c) hold electric field strengths and values related to electric field strengths. As an example, the larger the electric field strength is, the larger is the value corresponding to the electric field strength. Since the electric field strengths differ according to the access scheme, in the present exemplary embodiment, tables related to the electric field strengths are stored for each of the access schemes. It is to be noted that in the present exemplary embodiment, the larger the value corresponding to an electric field strength or access scheme is, the higher the priority order is for a communication interface.

For example, the mobile communication terminal 100 gives notification of information as in FIG. 8, as the communication quality information or the access scheme of communication interfaces #1 and #2, to the control apparatus 2. The access network selection unit 28, for example, uses the notified communication quality information or the access scheme, and a table related to the respective access schemes and electric field strengths, to determine priority of the communication interface.

Referring to the table of FIG. 9(a), in a case where the access scheme is W-CDMA a corresponding value is "2." Referring to the table of FIG. 9(b), in a case where the electric field strength is greater than or equal to 100 dBm, a corresponding value is "3." The access network selection unit 28, for example, adds up these values. In this case, a value of "5" is obtained for communication interface #1.

Referring to FIG. 9(a), in a case where the access scheme is 802.11g, a corresponding value is "3." Referring to FIG. 9(c), in a case where the electric field strength (x) is less than or equal to 60 dBm, a corresponding value is "1." The access network selection unit 28, for example, adds up these values. In this case, a value of "4" is obtained for communication interface #2.

Since the addition value of communication interface #1 is greater than the addition value of communication interface #2, the access network selection unit 28 selects the communication interface #1 as the interface to be used.

The function of the access network selection unit 28 described above is an example, and there is no limitation to the abovementioned function. For example, an example of the access network selection unit 28 was shown as selecting a communication interface based on the communication quality information or the access scheme, but the access network selection unit 28 may also select a communication interface based on the communication quality information.

FIG. 10 is a sequence diagram showing an example of an operation of the communication system according to the present exemplary embodiment. Referring to FIG. 10, a description is given of an operation of the communication system of the present exemplary embodiment. It is to be noted that the operation shown in FIG. 10 is exemplary, and operations of the present invention are not limited to the operations shown in FIG. 10.

The mobile communication terminal 100, for example, establishes a link with the W-CDMA network 6 and the 802.11g network 7.

The mobile communication terminal 100 establishes a control channel with the control apparatus 2, via the link established with the RAN.

The packet forwarding function unit 103 of the mobile communication terminal 100, for example, receives a packet from an application. In a case where no processing rule corresponding to the packet in question exists (that is, when a new packet is received) the packet forwarding function unit 103 makes a request for a processing rule to the control apparatus 2. It is to be noted that in the example of FIG. 10, the new packet is a packet for communicating with a server apparatus 5. When the request for the processing rule is made, the packet forwarding function unit 103 transmits the communication quality information, the access scheme, or the like.

The control apparatus 2, for example, gives consideration to the communication quality information or the access scheme notified by the mobile communication terminal 100, to determine a processing rule to be transmitted to the mobile communication terminal 100. The control apparatus 2 transmits the determined processing rule to the mobile communication terminal 100. The control apparatus 2 determines a forwarding path for the mobile communication terminal 100 to communicate with the server apparatus 5, and transmits a processing rule corresponding to the determined path to the packet forwarding apparatus 3.

In accordance with the received processing rule, the mobile communication terminal 100 communicates with the server apparatus 5 via the packet forwarding apparatus 3.

In the present exemplary embodiment, the access management unit 132 sends the electric field strength as dynamic information, as the communication quality information, to the control apparatus 2, but the dynamic communication quality information is not limited to electric field strength. For example, a modulation scheme presently being used may be cited as other dynamic communication quality information.

In the present exemplary embodiment, the access management unit 132 sends dynamic communication quality information to the control device 2, as the communication quality information, but static communication quality information may also be sent. Static information, for example, is information associated with a RAN or a link. Information associated with a RAN is information that does not vary during operation of the mobile communication terminal 100, as long as there is a connection to the same RAN. Information related to supported QoS (Quality of Service) information, security, or the like may be cited, for example, as information associated with the RAN. On the other hand, information associated with a link is non-varying information, where the mobile communication terminal 100 is limited to being connected to the same base station or access point. A supported cell identifier or an access point MAC (Media Access Control) address may be cited, for example, as information associated with a link.

The terminal information management unit 27 may hold a table as in FIG. 11. FIG. 11 shows an example of a table managed by the terminal information management unit 27 as information of the mobile communication terminal 100.

In a case where the table of FIG. 11 is held, the terminal information management unit 27 manages history of communication quality information, port status, or the like, for each mobile communication terminal 100 identifier.

By the terminal information management unit 27 holding a table as in FIG. 11, past communication quality information is held, so that it is possible to select an interface to be used from past trends.

(Second Exemplary Embodiment)
A description is given concerning a communication system related to a second exemplary embodiment, making reference to the drawings.

In the present exemplary embodiment, an access management unit 132 distinguishes respective methods of communication to a control device 2, with regard to static information and dynamic information or access scheme, in communication quality information.

The access management unit 132, for example, transmits dynamically varying communication quality information at timing when a control unit 130 makes a request for an instruction to the control apparatus 2. In a case where no processing rule corresponding to a packet exists, for example, the control unit 130 makes a request for a processing rule to the control apparatus 2. The access management unit 132, for example, transmits present information of the dynamically varying communication quality information at timing when the request for the processing rule is made to the control apparatus 2.

The access management unit 132, for example, transmits information such as static communication quality information, access scheme, or the like, by a Feature Reply to a Feature Request transmitted from the control apparatus 2.

By the access management unit 132 notifying the control apparatus 2 of dynamically varying communication quality information at a regular frequency, the control apparatus 2 can comprehend the present communication quality of the mobile communication terminal 100. On the other hand, by the access management unit 132 limiting notification of static communication quality information, access scheme or the like, it is possible to curtail message volume notified to the control apparatus 2 by the mobile communication terminal 100, and to economize on communication resources.

FIG. 12 is a sequence diagram showing an example of an operation of the communication system according to the present exemplary embodiment. Referring to FIG. 12, a description is given of an operation of the communication system of the present exemplary embodiment. The operation shown in FIG. 12 is exemplary, and operations of the present invention are not limited to the operations shown in FIG. 12.

The mobile communication terminal 100, for example, establishes a link with a W-CDMA network 6 and an 802.11g network 7.

The control apparatus 2 transmits a Feature Request to the mobile communication terminal 100, via the control channel.

The mobile communication terminal 100 responds, as a Feature Reply to the Feature Request, with static communication quality information, access scheme, or the like.

The packet forwarding function unit 103 of the mobile communication terminal 100, for example, receives a packet from an application. In a case where no processing rule corresponding to the packet in question exists (that is, when a new packet is received) the packet forwarding function unit 103 makes a request for a processing rule to the control apparatus 2. It is to be noted that in the example of FIG. 12, the new packet is a packet for communicating with the server device 5. When a request is made for a processing rule, the packet forwarding function unit 103 transmits dynamically varying communication quality information.

The control apparatus 2, for example, gives consideration to the communication quality information notified by the mobile communication terminal 100, to determine a processing rule to be transmitted to the mobile communication terminal 100. The control apparatus 2 transmits the determined processing rule to the mobile communication terminal 100. The control apparatus 2 determines a forwarding path for the mobile communication terminal 100 to communicate with the server device 5, and transmits a processing rule corresponding to the determined path to a packet forwarding apparatus 3.

In accordance with the received processing rule, the mobile communication terminal 100 communicates with the server device 5 via the packet forwarding apparatus 3.

In the present exemplary embodiment, the static information and access scheme were transmitted using a Feature Reply, but there is no limitation to this, and descriptions may be transmitted in a message related to a Port Status Message. For example, the mobile communication terminal 100 may transmit static information fixed when a control channel with the control apparatus 2 is established, using a Feature Reply, and static information fixed or changed after the control channel is established may be transmitted using a Port Status Message.

In the present disclosure, the following modes are possible.
(Mode 1)
A mobile communication terminal as mentioned at the first aspect.
(Mode 2)
In the mobile communication terminal, it is preferred that the processing means (unit) forwards the packet to one of the plurality of communication interfaces, in accordance with a policy determined by the control apparatus based on the communication quality information.
(Mode 3)
In the mobile communication terminal, it is preferred that the control means (unit) transmits the communication quality information via a communication channel established between the mobile communication terminal and the control apparatus.
(Mode 4)
In the mobile communication terminal, it is preferred that the control means transmits the communication quality information upon requesting the control apparatus for the instruction.
(Mode 5)
In the mobile communication terminal, it is preferred that the control means transmits the communication quality information upon requesting the control apparatus for an instruction with regard to a packet whose processing method is unknown.
(Mode 6)
In the mobile communication terminal, it is preferred that the communication quality information is dynamically varying information on communication quality.
(Mode 7)
In the mobile communication terminal, it is preferred that the control means (unit) transmits the communication quality information at a point of time when the mobile communication terminal requests the control apparatus for the instruction.
(Mode 8)
In the mobile communication terminal, it is preferred that the communication quality information is static information on static communication.
(Mode 9)
In the mobile communication terminal, it is preferred that the control means (unit) transmits the communication quality information in response to a request from the control apparatus.
(Mode 10)
A communication method as mentioned at the second aspect.
(Mode 11)
In the communication method, it is preferred to comprise:
by the mobile communication terminal, forwarding the packet to one of the plurality of communication interfaces, in accordance with a policy determined by the control apparatus based on the communication quality information.
(Mode 12)
In the communication method, it is preferred to comprise:
by the mobile communication terminal, transmitting the communication quality information via a communication channel established between the mobile communication terminal and the control apparatus.
(Mode 13)
In the communication method, it is preferred to comprise:
by the mobile communication terminal, transmitting the communication quality information upon requesting the control apparatus for the instruction.
(Mode 14)
In the communication method, it is preferred to comprise:
by the mobile communication terminal, transmitting the communication quality information upon requesting the control apparatus for an instruction with regard to a packet whose processing method is unknown.
(Mode 15)
In the communication method, it is preferred that the communication quality information is dynamically varying information on communication quality.
(Mode 16)
In the communication method, it is preferred to comprise:
by the mobile communication terminal, transmitting the communication quality information at a point of time when the mobile communication terminal requests the control apparatus for the instruction.
(Mode 17)
In the communication method, it is preferred that the communication quality information is static information on communication quality.
(Mode 18)
The communication method, it is preferred to comprise:
by the mobile communication terminal, transmitting the communication quality information in response to a request from the control apparatus.
(Mode 19)
A communication system as mentioned at the third aspect.
(Mode 20)
A control apparatus as mentioned at the fourth aspect.
(Mode 21)
A mobile communication terminal as mentioned at the fifth aspect.

Descriptions have been given above of various exemplary embodiments of the present invention, but the present invention is not limited to the abovementioned modes or exemplary embodiments, and further modifications, substitutions and adjustments may be added within a scope that does not depart from fundamental technical concepts of the present invention. Furthermore, the respective exemplary embodiments may be implemented in combination, as appropriate.

It is to be noted that each disclosure of the abovementioned Patent Literature and Non-Patent Literatures is incorporated herein by reference thereto. Modifications and adjustments of the exemplary embodiment are possible within the scope of the overall disclosure (including the claims) of the present invention and based on the basic technical concept of the present invention. Various combinations and selections of various disclosed elements (including each element of each claim, each element of each mode or exemplary embodiment, each element of each drawing, etc.) are possible within the scope of the claims of the present invention. That is, the present invention of course includes various variations and modifications that could be made by those skilled in the art according to the overall disclosure including the claims and the technical concept. Particularly, any numerical range disclosed herein should be interpreted that any intermediate values or subranges falling within the disclosed range are also concretely disclosed even without specific recital thereof.

1 mobile communication terminal
2 control apparatus
3 packet forwarding apparatus
4 network
5 server apparatus
6 W-CDMA network
7 802.11g network
10 communication interface
11 processing unit
12 control unit
13 packet forwarding function unit
20 node communication unit
21 control message processing unit
22 calculation unit
23 DB management unit
24 topology management unit
25 location management unit
26 processing rule DB
27 terminal information management unit
28 access network selection unit
100 mobile communication terminal
101 application unit
102 protocol stack unit
103 packet forwarding function unit
104 port
105 communication interface
130 control unit
131 processing unit
132 access management unit
133 access management DB
134 processing rule management unit
135 processing rule DB
136 search unit
137 action execution unit

Claims

A mobile communication terminal that communicates with a network including a control apparatus that controls packet forwarding, the mobile communication terminal comprising:
a plurality of communication interfaces for wireless communication;
a processing means that processes a packet in accordance with an instruction from the control apparatus; and
a control means that transmits to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information.
The mobile communication terminal according to claim 1, wherein the processing means forwards the packet to one of the plurality of communication interfaces, in accordance with a policy determined by the control apparatus based on the communication quality information.
The mobile communication terminal according to claim 1, wherein the control means transmits the communication quality information via a communication channel established between the mobile communication terminal and the control apparatus.
The mobile communication terminal according to claim 1, wherein the control means transmits the communication quality information upon requesting the control apparatus for the instruction.
The mobile communication terminal according to claim 1, wherein the control means transmits the communication quality information upon requesting the control apparatus for an instruction with regard to a packet whose processing method is unknown.
The mobile communication terminal according to claim 1, wherein the communication quality information is dynamically varying information on communication quality.
The mobile communication terminal according to claim 6, wherein the control means transmits the communication quality information at a point of time when the mobile communication terminal requests the control apparatus for the instruction.
The mobile communication terminal according to claim 1, wherein the communication quality information is static information on static communication.
The mobile communication terminal according to claim 8, wherein the control means transmits the communication quality information in response to a request from the control apparatus.
A communication method by a mobile communication terminal that communicates with a network including a control apparatus that controls packet forwarding and includes a plurality of communication interfaces for wireless communication, the method comprising:
processing a packet in accordance with an instruction from the control apparatus; and
transmitting to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information.
The communication method according to claim 10, comprising:
by the mobile communication terminal, forwarding the packet to one of the plurality of communication interfaces, in accordance with a policy determined by the control apparatus based on the communication quality information.
The communication method according to claim 10, comprising:
by the mobile communication terminal, transmitting the communication quality information via a communication channel established between the mobile communication terminal and the control apparatus.
The communication method according to claim 10, comprising:
by the mobile communication terminal, transmitting the communication quality information upon requesting the control apparatus for the instruction.
The communication method according to claim 10, comprising:
by the mobile communication terminal, transmitting the communication quality information upon requesting the control apparatus for an instruction with regard to a packet whose processing method is unknown.
The communication method according to claim 10, wherein the communication quality information is dynamically varying information on communication quality.
The communication method according to claim 15, comprising:
by the mobile communication terminal, transmitting the communication quality information at a point of time when the mobile communication terminal requests the control apparatus for the instruction.
The communication method according to claim 10, wherein the communication quality information is static information on communication quality.
The communication method according to claim 17, comprising:
by the mobile communication terminal, transmitting the communication quality information in response to a request from the control apparatus.
A communication system, comprising:
a control apparatus that controls packet forwarding; and
a mobile communication terminal that communicates with a network including the control apparatus, wherein
the mobile communication terminal comprises:
a plurality of communication interfaces for wireless communication;
a processing means that processes a packet in accordance with an instruction from the control apparatus; and
a control means that transmits to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information.
A control apparatus that controls packet forwarding, the control apparatus comprising:
a means that receives, from a mobile communication terminal that includes a plurality of communication interfaces for wireless communication and processes a packet in accordance with an instruction from the control apparatus, communication quality information representing communication quality of each of the plurality of communication interfaces; and
a means that transmits to the mobile communication terminal an instruction determined based on the communication quality information.
A mobile communication terminal that communicates with a network including a control apparatus that controls packet forwarding, the mobile communication terminal comprising:
a plurality of communication interfaces for wireless communication; and
a means that downloads a program, wherein
the program causes the mobile communication terminal to execute:
processing of a packet in accordance with an instruction from the control apparatus; and
transmitting to the network communication quality information representing communication quality of each of the plurality of communication interfaces to notify the control apparatus of the communication quality information.