Description
Title of Invention: WIRELESS COMMUNICATION TERMINAL,
COMMUNICATION SYSTEM, CONTROL APPARATUS, COM¬
MUNICATION METHOD AND PROGRAM
Technical Field
[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS)
The present application claims priority from Japanese Patent Application No.
2012-023810 (filed on February 7, 2012) the content of which is hereby incorporated
in its entirety by reference into this application. The present invention relates to a
wireless communication terminal, a communication system, a control apparatus, a
communication method and a program, and in particular, relates to a wireless commu
nication terminal, a communication system, a control apparatus, a communication
method and a program, which perform communication with a plurality of wireless (or
radio) access systems (or methods).
Background
[0002] In recent years, it is possible for mobile terminals to connect to multiple types of
RAT (Radio Access Technology). For example, a mobile terminal can connect to
multiple RATs, such as 3GPP access including UTRAN (UMTS Terrestrial Radio
Access Network) or LTE (Long Term Evolution), and WLAN (Wireless Local Area
Network) including 802. 1l g or 802. 1In.
[0003] The mobile terminal communicates according to an access environment by making
an appropriate change to a RAT used for communication.
[0004] With regard to handover of a mobile terminal, Patent Literature 1 (Japanese Patent
No. 4703657) discloses the following technology. A server present in a network in this
literature refers to location information of a mobile terminal and notifies a list of access
points (AP), authentication servers, and the like, present in a prescribed geographical
range, to the mobile terminal. The server notifies the list of AP, authentication servers,
and the like, that are present in an area adjacent to the network area where the mobile
terminal is currently, to the mobile terminal. The mobile terminal performs handover
from the network area where the mobile terminal is currently located, to the adjacent
area. Prior to performing handover, the mobile terminal refers to the notified list and
performs authentication in advance with respect to the AP and authentication servers.
By performing authentication beforehand, prior to handover, authentication when
handover is performed can be omitted. Therefore, there is a description that the mobile
terminal can perform handover at high speed.
Citation List
Patent Literature
[0005] PTL 1: Japanese Patent No. 4703657
Summary
Technical Problem
[0006] The following analysis is given by the present invention. In an environment where a
mobile terminal can connect to a plurality of RATs, the following problem occurs
when judging a RAT to which the mobile terminal connects.
[0007] A user of the mobile terminal can switch a RAT manually in accordance with an
access environment, but performing manual operations each time the environment
changes is cumbersome.
[0008] In addition, consideration can be given to having the mobile terminal hold a policy in
advance related to RAT selection, but since the access environment changes from day
to day, it is difficult to select a RAT to correspond with changes in access environment
with a pre-set policy.
[0009] In the abovementioned Patent Literature 1, a server notifies a mobile terminal of a list
of access points present in an area adjacent to a network area in which the mobile
terminal is present. However, there is a problem in that, with only the list, the mobile
terminal cannot judge a RAT to which it should connect.
[0010] It is an object of the present invention to provide a configuration or means that can
contribute to enable a wireless communication terminal provided with multiple types
of communication interface to select a more desirable communication interface.
Solution to Problem
[001 1] According to a first aspect, there is provided a wireless communication terminal,
comprising: a plurality of communication interfaces each of which corresponds to at
least one of a plurality of wireless access systems; means (a unit) for receiving an in
struction from a prescribed control apparatus, the instruction including a wireless
access system determined by the control apparatus based on a status of the wireless
communication terminal, which changes along with movement of the wireless commu
nication terminal; and means (a unit) for communicating by using a communication
interface corresponding to the instructed wireless access system.
[0012] According to a second aspect, there is provided a communication system comprising:
a control apparatus that controls wireless access systems to which a wireless commu
nication terminal connects; a plurality of communication interfaces each of which cor
responds to at least one of the wireless access systems; means (a unit) for receiving an
instruction from a prescribed control apparatus, the instruction including a wireless
access system determined by the control apparatus based on a status of the wireless
communication terminal, which changes along with movement of the wireless communication
terminal; and means (a unit) for communicating by using a communication
interface corresponding to the instructed wireless access system.
[0013] According to a third aspect, there is provided a control apparatus comprising: means
(a unit) for receiving a status of a wireless communication terminal, which changes
along with movement of the wireless communication terminal; means (a unit) for de
termining a wireless access system to which the wireless communication terminal
connects, based on the received status of the wireless communication terminal; and
means (a unit) for transmitting an instruction including the determined wireless access
system, to the wireless communication terminal.
[0014] According to a fourth aspect, there is provided a communication method using a
wireless communication terminal including a plurality of communication interfaces
corresponding to at least one of a plurality of wireless access systems. The method
comprises: receiving, from a prescribed control apparatus, an instruction including a
wireless access system determined by the control apparatus based on a status of the
wireless communication terminal, which changes along with movement of the wireless
communication terminal; and communicating by using a communication interface cor
responding to the instructed wireless access system. This method is associated with a
particular machine known as a wireless communication terminal provided with a
plurality of communication interfaces corresponding to at least one of a plurality of
wireless access systems.
[0015] According to a fifth aspect, there is provided a program that executes on a wireless
communication terminal including a plurality of communication interfaces corre
sponding to at least one of a plurality of wireless access systems. The program
comprises: a process of receiving, from a prescribed control apparatus, an instruction
including a wireless access system determined by the control apparatus based on a
status of the wireless communication terminal, which changes along with movement of
the wireless communication terminal, and a process of communicating by using a com
munication interface corresponding to the instructed wireless access system. This
program may be recorded on a computer-readable storage medium which is nontransitory.
That is, the present invention may be embodied as a computer program
product.
Advantageous Effects of Invention
[0016] According to the present invention a wireless communication terminal provided with
multiple types of communication interface can contribute to select a more desirable
communication interface.
Brief Description of Drawings
[0017] [fig. 1]FIG. 1 is a diagram showing an example of a communication system in a first
exemplary embodiment of the present disclosure.
[fig.2]FIG. 2 is a diagram showing a configuration example of a wireless commu
nication terminal in the first exemplary embodiment.
[fig.3]FIG. 3 is a sequence diagram showing an operational example of the first
exemplary embodiment.
[fig.4]FIG. 4 is a diagram showing a configuration example of a control apparatus in a
second exemplary embodiment of the present disclosure.
[fig.5]FIG. 5 is a diagram showing a configuration example of a policy DB of the
control apparatus in the second exemplary embodiment.
[fig.6]FIG. 6 is a diagram showing a configuration example of a policy DB of the
control apparatus in the second exemplary embodiment.
[fig.7]FIG. 7 is a diagram showing a configuration example of a policy DB of the
control apparatus in the second exemplary embodiment.
[fig.8]FIG. 8 is a diagram showing a configuration example of a policy DB of the
control apparatus in the second exemplary embodiment.
[fig.9]FIG. 9 is a diagram describing technology related to a third exemplary em
bodiment of the present disclosure.
[fig. 10]FIG. 10 is a diagram describing technology related to the third exemplary em
bodiment.
[fig. 11]FIG. 11 is a diagram showing an example of a communication system in the
third exemplary embodiment.
[fig. 12]FIG. 12 is a diagram showing a configuration example of a wireless commu
nication terminal in the third exemplary embodiment.
[fig.l3]FIG. 13 is a diagram showing a configuration example of the wireless commu
nication terminal in the third exemplary embodiment.
[fig. 14]FIG. 4 is a diagram showing a configuration example of a control apparatus in
the third exemplary embodiment.
[fig.l5]FIG. 15 is a sequence diagram showing an operational example of the third
exemplary embodiment.
[fig. 16]FIG. 16 is a sequence diagram showing an operational example of a fourth
exemplary embodiment of the present disclosure.
[fig. 17]FIG. 17 is a diagram showing a configuration example of a policy DB of a
control apparatus in a fifth exemplary embodiment of the present disclosure
[fig. 18]FIG. 18 is a diagram showing a configuration example of a policy DB of the
control apparatus in the fifth exemplary embodiment.
[fig. 19]FIG. 19 is a diagram showing a configuration example of a policy DB of a
control apparatus in a sixth exemplary embodiment of the present disclosure.
Description of Embodiments
[0018] Next, a detailed description is given of exemplary embodiments of the present
invention, making reference to the drawings.
(First Exemplary Embodiment)
As shown in FIG. 1, a first exemplary embodiment can be implemented by a con
figuration including a wireless (or radio) communication terminal 1, a control
apparatus 2, a network 3, and RATs 4. It is to be noted that reference symbols in the
drawing are added as examples in order facilitate understanding, and are not intended
to limit the present disclosure to modes shown in the drawings.
[0019] The wireless communication terminal 1 has communication interfaces corresponding
to plural wireless access systems (RAT 4 in FIG. 1). The wireless communication
terminal 1 connects with any RAT (UTRAN 4-1, WLAN 4-2, WLAN 4-3, and WLAN
4-4) shown as examples in FIG. 1, to communicate with the network 3. It is to be noted
that the wireless communication terminal 1 may connect with a plurality of RATs (for
example, UTRAN 4-1 and WLAN 4-2), among the RATs shown as examples in FIG.
1, to communicate with the network 3.
[0020] The wireless communication terminal 1 is a device having a communication
function, such as a mobile telephone, a personal computer, a mobile router, or the like.
It is to be noted that the mobile router is a terminal that relays to a 3G line for mobile
telephones or a wireless LAN network.
[0021] The RAT 4 is a wireless access network for the wireless communication terminal 1 to
connect to the network 3. In FIG. 1, UTRAN and WLAN are shown as examples of a
RAT, but RAT types in the present invention are not limited to the examples of FIG. 1.
The RATs include, for example, wireless access networks such as LTE, WiMAX
(Worldwide Interoperability for Microwave Access), and the like.
[0022] The control apparatus 2 determines a RAT to which the wireless communication
terminal 1 connects, and instructs the wireless communication terminal 1 to com
municate by the determined RAT. The control apparatus 2 is disposed in the network
3, for example, and the wireless communication terminal 1 connects with the RAT 4
and communicates with the control apparatus 2 via the network 3. The control
apparatus 2 is an apparatus that is physically separated from the wireless commu
nication terminal 1. It is to be noted that the location at which the control apparatus 2 is
disposed is not limited to that of FIG. 1, and may be disposed in an access network on
a per-RAT basis. Furthermore, the control apparatus 2 may be disposed in a data center
that can communicate with the network 3.
[0023] FIG. 2 shows a configuration example of the wireless communication terminal 1. The
wireless communication terminal 1 includes a plurality of communication interfaces
10, a control unit 11, and a communication unit 12. It is to be noted that the con
figuration shown in FIG. 2 is an example, and the configuration of the wireless com
munication terminal 1 is not limited to the example of FIG. 2.
[0024] A communication interface 10 is, for example, an antenna. Each of the commu
nication interfaces 10 corresponds to at least one of the plurality of RATs. For
example, the communication interface 10 corresponds to a specific RAT (for example,
UTRAN 4-1), and the wireless communication terminal 1 connects with a specific
RAT (for example, UTRAN 4-1) via this communication interface 10. Furthermore,
for example, the communication interface 10 corresponds to a plurality of RATs (for
example, WLAN 4-2 and 4-3), and the wireless communication terminal 1 connects
with any of the plurality of RATs that are corresponding, via this communication
interface 10.
[0025] The control unit 11 includes a monitoring unit 111, a notification unit 112, and an
access management unit 113. The monitoring unit 111 monitors a status that changes
in accordance with movement of the wireless communication terminal 1. The status
that changes in accordance with movement is, for example, the location of the wireless
communication terminal 1, the RAT that can be used by the wireless communication
terminal 1, radio wave reception strength of each communication interface, or the like.
The monitoring unit 111, for example, searches for a RAT 4 that is useable around the
wireless communication terminal 1, via the respective communication interfaces 10.
The monitoring unit 111 searches for a useable RAT 4, via all of the communication
interfaces 10. The monitoring unit 111 may search for a useable RAT 4 via an interface
that is activated, among the plurality of communication interfaces. The monitoring unit
111 may search for a useable RAT via a communication interface instructed by the
access management unit 113. The monitoring unit 111, for example, searches for a
useable RAT 4, based on radio wave states corresponding to the respective RATs 4.
[0026] The monitoring unit 111 may measure information related to the location of the
wireless communication terminal 1, or information related to the radio wave state such
as radio wave reception strength or the like, via the communication interfaces 10. The
information related to the location of the wireless communication terminal 1, for
example, is GPS information, cell ID (the ID of a cell corresponding to a cover area of
a wireless base station), or the like.
[0027] The monitoring unit 111 monitors the state of the wireless communication terminal 1
at a prescribed timing. For example, the monitoring unit 111 monitors the state of the
wireless communication terminal 1 at a prescribed period. The monitoring unit 111
may monitor the state of the terminal when an instruction is given by the access
management unit 113.
[0028] The monitoring unit 111 may monitor the amount of movement of the wireless communication
terminal 1 at regular intervals, and may monitor the status of useable RATs
only when the amount of movement is greater than or equal to a prescribed threshold.
When a monitoring operation such as scanning of RAT information or the like is
performed frequently, power consumption of the wireless communication terminal 1
increases. However, when the amount of movement of the wireless communication
terminal 1 is small, since the probability of the state of the wireless communication
terminal 1 changing is low, there is little need to frequently perform monitoring op
erations. Therefore, by controlling the period and frequency of monitoring operations
in accordance with the amount of movement of the wireless communication terminal 1
it is possible to curtail the power consumption of the wireless communication terminal
1.
[0029] The notification unit 112 notifies the control apparatus 2, via the communication unit
12, of information related to the status of the wireless communication terminal 1
(referred to below as status information), which is monitored by the monitoring unit
111. It is to be noted that the notification unit 112 notifies the status information to the
control apparatus 2 by a communication interface 10 corresponding to a RAT for
which a link is established by the wireless communication terminal 1. The notification
unit 112 may notify an identifier of the wireless communication terminal 1 together
with the status information, to the control apparatus 2. The notification unit 112, for
example, notifies, as status information, an identifier of a detected RAT or information
related to radio wave state such as reception electric field strength, to the control
apparatus 2. The RAT identifier, for example, is an SSID (Service Set Identifier) or
PLMN (Public Land Mobile Network) identifier. The notification unit 112 may notify
information related to the location of the wireless communication terminal 1 as status
information to the control apparatus 2. The information related to the location of the
wireless communication terminal 1, for example, is GPS information, cell ID (the ID
of a cell corresponding to a cover area of a wireless base station), or the like.
[0030] The communication unit 12 transmits/receives data via the communication interface.
The communication unit 12 communicates with the control apparatus 2 via the com
munication interface. The communication unit 12, for example, refers to a network
address of the control apparatus 2 set in advance in the wireless communication
terminal 1 and communicates with the control apparatus 2. The communication unit 12
is a communication line of a network operator to which the wireless communication
terminal 1 is subscribed, and may obtain the address of the control apparatus 2 from
the network side when connected to a RAT to which the wireless communication
terminal 1 attempts to establish a link when active. For example, when a wireless
station of a RAT for which a link is established is requested to generate a logic channel
(for example, a bearer), the communication unit 12 also requests the address (IP
address or the like) of the control apparatus 2. The communication unit 12 may access
the control apparatus 2 using a prescribed URL (Uniform Resource Locator), and may
establish a VPN (Virtual Private Network) with the control apparatus 2. Methods by
which the communication unit 12 communicates with the control apparatus 2 are not
limited to the abovementioned method.
[0031] The control apparatus 2, for example, determines the RAT to be used by the wireless
communication terminal 1, based on the status information notified by the wireless
communication terminal 1. The control apparatus 2 transmits an instruction to com
municate by the determined RAT to the wireless communication terminal 1.
[0032] The control apparatus 2 may determine the RAT to be used by the wireless commu
nication terminal 1 based on information notified by another apparatus, rather than the
status information notified by the wireless communication terminal 1. For example, in
mobile IP technology specified by RFC 2002 or the like, the control apparatus 2 can
obtain the status information of the wireless communication terminal 1 without
receiving information from the wireless communication terminal 1. In a mobile IP, a
home agent (HA) uses a unique address (Home Address) in the wireless commu
nication terminal 1, and an address (Care-of Address) for specifying a movement des
tination network of the wireless communication terminal 1, to manage the location of
the wireless communication terminal 1. The wireless communication terminal 1
connects with a foreign agent (FA) in accordance with movement, and obtains a careof
address from the FA. That is, the care-of address changes in accordance with
movement of the wireless communication terminal 1. The HA receives the home
address and the care-of address from the wireless communication terminal 1 or the FA,
and manages the location of the wireless communication terminal 1. The control
apparatus 2 may obtain the location information for the wireless communication
terminal 1 from the HA, and may determine the RAT to be used by the wireless com
munication terminal 1, based on this location information.
[0033] The control apparatus 2 may determine the RAT to which the wireless commu
nication terminal 1 connects, and may specify a connection device (for example, a
WiFi access point or the like) for connecting to this RAT. The control apparatus 2 may
instruct the wireless communication terminal 1 to connect to the specified connection
device. The control apparatus 2, for example, notifies the SSID of a WiFi access point
to the wireless communication terminal 1, and instructs that connection be made to the
access point with this SSID.
[0034] The access management unit 113 manages connection of the communication
interface 10 and the RAT 4. The access management unit 113 controls the wireless
communication terminal 1 so as to communicate using the communication interface
corresponding to the instructed RAT, based on the instruction from the control
apparatus. 2.
[0035] It is to be noted that the control unit 11 of the wireless communication terminal 1 can
also be configured by an application program. For example, the wireless commu
nication terminal 1 may download an application program having a function corre
sponding to the control unit 11, from a server in the network. A server that delivers the
application program to the wireless communication terminal 1, for example, is
provided with a function that communicates with the wireless communication terminal
1 via the network 3 of the communication system shown in FIG. 1, and delivers an ap
plication program corresponding to the control unit 11 to the wireless communication
terminal 1.
[0036] FIG. 3 is a sequence diagram showing an operational example of an exemplary em
bodiment of the present invention. It is to be noted that, as shown in FIG. 3, operations
of the present invention are not limited to those of FIG. 3.
[0037] The wireless communication terminal 1 establishes a link with a prescribed RAT (for
example, UTRAN 4-1) (step S001). The wireless communication terminal 1, for
example, establishes the link with the prescribed RAT when operation is started (for
example, when a power supply is turned on). At this occasion, the wireless commu
nication terminal 1 establishes a link with this RAT by a communication interface 10
corresponding to the prescribed RAT. The prescribed RAT, for example, is a commu
nication line of a network operator to which the wireless communication terminal 1 is
subscribed, and is a RAT that attempts to establish a link when the wireless commu
nication terminal 1 is activated.
[0038] The wireless communication terminal 1 monitors the state of the wireless commu
nication terminal 1 at prescribed timing (step S002).
[0039] The wireless communication terminal 1 notifies the monitored state (status in
formation) to the control apparatus 2 via the prescribed RAT for which a link has
already been established (step S003).
[0040] The control apparatus 2, for example, determines the RAT to be used by the wireless
communication terminal 1 based on the received status information (step S004). The
control apparatus 2 transmits an instruction including the determined RAT or an in
struction using the determined RAT to the wireless communication terminal 1 (step
S005).
[0041] The wireless communication terminal 1 establishes a link with the instructed RAT
based on the instruction from the control apparatus 2, and communicates using the
communication interface corresponding to that RAT (step S006).
[0042] By the configuration example shown in the abovementioned exemplary embodiment,
in the present invention, even with a configuration that supports a plurality of RATs,
the wireless communication terminal 1 can easily judge a RAT to be connected to, by
following the instruction from the control apparatus 2. Since the RAT to be connected
is determined following the instruction from the control apparatus 2, a user of the
wireless communication terminal 1 need not perform the cumbersome task of manually
selecting the RAT.
[0043] Furthermore, since the RAT to be connected to the wireless communication terminal
1 is determined based on the state of the wireless communication terminal 1, it is
possible to use a more desirable RAT, a RAT corresponding to the access environment
of the wireless communication terminal 1.
[0044] It is to be noted that in the present embodiment the wireless communication terminal
1 notified the status information directly to the control apparatus 2, but the method of
notifying the status information to the control apparatus 2 is not limited thereto. For
example, a wireless base station of a prescribed RAT (for example, UTRAN 4-1) may
receive radio wave reception strength from an adjacent wireless base station monitored
via a corresponding communication interface by the wireless communication terminal
1, from the wireless communication terminal 1, and may notify the received in
formation to the control apparatus 2.
[0045] (Second Exemplary Embodiment)
Next, a description is given of a second exemplary embodiment of the present
disclosure, making reference to the drawings. A configuration example of a commu
nication system of the second exemplary embodiment is similar to FIG. 1. That is, the
second exemplary embodiment can be implemented by a configuration including a
wireless communication terminal 1, a control apparatus 2, a network 3, and RATs 4.
[0046] In the second exemplary embodiment, a configuration of the wireless communication
terminal 1 is the same as in FIG. 2. In the second exemplary embodiment, the control
apparatus 2 determines a RAT based on status information that changes along with
movement of the wireless communication terminal 1. With regard to the configuration
otherwise, operations are the same as in the first exemplary embodiment described
above, and detailed descriptions are omitted.
[0047] FIG. 4 shows a configuration of the control apparatus 2 in the second exemplary em
bodiment. The control apparatus 2 of the present exemplary embodiment includes a
communication unit 20, a control unit 21, and a policy DB (data base) 22.
[0048] The communication unit 20 communicates with the wireless communication terminal
1. The communication unit 20, for example, receives status information transmitted
from the wireless communication terminal 1. The communication unit 20 transmits an
instruction to communicate by a RAT determined based on the received status in
formation, to the wireless communication terminal 1.
[0049] The control apparatus 21, for example, determines the RAT to which the wireless
communication terminal 1 connects, based on the status information received from the
wireless communication terminal 1. The control unit 2 1 refers to the policy DB 22 to
determine the RAT.
[0050] FIG. 5 shows a configuration example of the policy DB 22. It is to be noted that FIG.
5 is an example, and the configuration of the policy DB 22 is not limited to the
example of FIG. 5.
[0051] In FIG. 5, the policy DB 22 has, as a rule ("selection rule" in the drawing) for de
termining a RAT, an identifier of a RAT to be selected, for each RAT. The policy DB
22, for example, holds data in a structure shown in FIG. 5 for each wireless commu
nication terminal 1. The policy DB 22, for example, holds data in the structure shown
in FIG. 5 for each identifier (for example, IMSI (International Mobile Subscriber
Identity) and the like) of a wireless communication terminal 1.
[0052] The control apparatus 2 1 determines the RAT to which the wireless communication
terminal 1 connects, by referring to the status information received from the wireless
communication terminal 1 and the policy DB 22. The status information, for example,
includes the identifier of a RAT detected by the wireless communication terminal 1.
The RAT identifier, for example, is a PLMN (Public Land Mobile Network) identifier
or the like, which is identification information of a UTRAN or the like.
[0053] The control unit 21, for example, searches the policy DB 22 for data corresponding
to the identifier of the wireless communication terminal 1 that has transmitted the
status information. The control unit 2 1 compares the identifier of the RAT included in
the received status information, and the identifier specified in a selection rule of the
policy DB 22. In a case where the identifier included in the status information matches
the identifier specified in the selection rule, the control unit 2 1 determines the RAT
corresponding to the matching identifier as the RAT to which the wireless commu
nication terminal 1 connects. In the example of FIG. 5, in a case where the status in
formation includes an SSID (A), which is an identifier of the WLAN 4-3 of FIG. 1, the
control unit 2 1 instructs the wireless communication terminal 1 to connect to the
WLAN 4-3.
[0054] In a case where the status information includes information related to radio wave
state, such as electric field strength or the like, the control unit 2 1 may determine the
RAT by referring to this information. In a case where an identifier included in the
status information matches the identifier specified in a selection rule, for example, the
control unit 2 1 makes a selection that has a good radio wave state, among matching
identifiers.
[0055] The policy DB 22 may include priorities. FIG. 6 shows an example of a case where
the policy DB 22 has priorities. It is to be noted that FIG. 6 is an example, and the con
figuration of the policy DB 22 is not limited to the configuration of FIG. 6. The policy
DB 22, for example, has priorities with regard to RATs (access systems) and priorities
for respective selection rules of each RAT (that is, for respective identifiers of each
RAT). The policy DB 22 can hold a database of a structure shown in FIG. 6, for each
wireless communication terminal 1.
[0056] In a case where the status information received from the wireless communication
terminal 1 includes information related to a plurality of RATs, for example, the control
unit 2 1 refers to the priorities for each of the RATs and selects a RAT with highest
priority.
[0057] In a case where the status information includes a plurality of identifiers for a certain
RAT, for example, the control unit 2 1 refers to priorities for selection rules, and selects
an access network corresponding to a high priority identifier.
[0058] In the example of FIG. 6, in a case where the status information includes a UTRAN
identifier and a WLAN identifier, the control unit 2 1 instructs the wireless commu
nication terminal 1 to connect to the WLAN that has high priority. In a case where the
status information includes SSID (B), which is an identifier of a WLAN 4-2, and SSID
(A), which is an identifier of a WLAN 4-3, the control unit 2 1 instructs the wireless
communication terminal 1 to connect to the WLAN 4-3 that has high priority.
[0059] The control unit 2 1 may select the RAT in accordance with type of communication
flow. FIG. 7 shows an example of the policy DB 22 in a case where the control unit 2 1
selects a RAT in accordance with type of communication flow. It is to be noted that
FIG. 7 is an example, and the configuration of the policy DB 22 is not limited to the
configuration of FIG. 7.
[0060] In the policy DB 22, RATs that are selection candidates are specified for respective
types of communication flow. It is to be noted that the policy DB 22 may specify a
plurality of RATs that are selection candidates for the respective types of commu
nication flow, and may have priorities for respective RATs.
[0061] In the example of FIG. 7, in a case where it is confirmed that the wireless commu
nication terminal 1 can connect to both UTRAN and WLAN, from the status in
formation, the control unit 2 1 instructs the wireless communication terminal 1 to com
municate using the WLAN for Web communication, and to communicate using the
UTRAN for VoIP (Voice over IP) communication. The wireless communication
terminal 1, in accordance with the instruction, communicates using a communication
interface corresponding to the WLAN in Web communication, and communicates
using a communication interface corresponding to UTRAN in VoIP communication.
That is, the wireless communication terminal 1 switches the communication interface
for each communication flow. In this case also, the policy DB 22 can hold a database
of a structure of FIG. 7 for each wireless communication terminal 1.
[0062] The control unit 2 1 may select the RAT based on location information of the wireless
communication terminal 1. FIG. 8 shows an example of the policy DB 22 in a case
where the control unit 2 1 selects a RAT based on location information. It is to be noted
that FIG. 8 is an example, and the configuration of the policy DB 22 is not limited to
the configuration of FIG. 8.
[0063] The location information of FIG. 8 is, for example, GPS information or cell ID. In a
case where the location information is GPS information, the location of the wireless
communication terminal 1 is expressed by latitude, longitude, and altitude, for
example. In a case where the location information is the cell ID, the location of the
wireless communication terminal 1 is estimated from, for example, the cell ID and
radio wave reception strength measured by the wireless communication terminal 1 for
the cell ID in question. The control unit 21, for example, estimates how far the wireless
communication terminal 1 is separated from the center of the cell by the radio wave
reception strength, and estimates the location of the wireless communication terminal
1. In a case of the cell ID, the location may be estimated using a plurality of cell IDs (a
set of a plurality of cell IDs and radio wave reception strengths is also possible), rather
than a single cell ID (a set of a single cell ID and radio wave reception strength is also
possible). In this case also, the policy DB 22 can hold a database of a structure of FIG.
8, for each wireless communication terminal 1.
[0064] In the example of FIG. 8, the policy DB 22 has a database associated with a RAT
that is a candidate for connection with the wireless communication terminal 1, with
respect to each location information item. For example, the policy DB 22 manages
RATs that are usable by the wireless communication terminal 1, for each location in
formation item.
[0065] For example, a WiFi access point is disposed at a prescribed location for each
network operator. Therefore by obtaining information related to the disposition of the
access point from the network operator in advance, the control apparatus 2 can
recognize a correspondence relationship between the location information and a RAT
corresponding to the access point. The wireless communication terminal 1 can use the
access point of a network operator to which it is subscribed. Accordingly, by referring
to subscription information between the wireless communication terminal 1 and the
network operator, and to the disposition of the access point of the network operator, the
control apparatus 2 can recognize a correspondence relationship between the location
information and a useable RAT, for each wireless communication terminal 1, and can
build the policy DB 22 shown in FIG. 8. The control apparatus 2 may obtain the in
formation related to the network operator to which the wireless communication
terminal 1 is subscribed, from the wireless communication terminal 1, or may obtain
the information from the network operator.
[0066] The control unit 2 1 refers to the policy DB 22 to identify a RAT corresponding to the
location information received from the wireless communication terminal 1. The control
apparatus 2 1 determines the RAT to which the wireless communication terminal 1
connects, from the RAT identified based on the location information. The control unit
21, for example, may determine the RAT by a method described with reference to FIG.
6 and FIG. 7, from RAT candidates identified based on the location information (a
method based on priorities and communication flows).
[0067] The control unit 2 1 can determine a RAT to which the wireless communication
terminal 1 connects by any method described with reference to FIG. 5, FIG. 6, FIG. 7,
and FIG. 8. The control unit 2 1 may determine a RAT by arbitrarily combining
methods described with reference to FIG. 5, FIG. 6, FIG. 7, and FIG. 8.
[0068] As described above, by the control apparatus 2 determining the RAT to which the
wireless communication terminal 1 connects based on the policy DB 22, it is possible
to easily select the RAT in accordance with the access environment of the wireless
communication terminal 1.
[0069] In addition, by the control apparatus 2 switching the RAT to which the wireless com
munication terminal 1 connects in accordance with a communication flow, network
traffic of the wireless communication terminal 1 can be controlled by the network
operator. By switching the RAT to which the wireless communication terminal 1
connects, the network operator can spread the network traffic of the wireless commu
nication terminal 1 among a plurality of RATs. In this way, it is possible for the
network operator to spread the communication amount, which is continually increasing
in recent years.
[0070] (Third Exemplary Embodiment)
Next, a description is given of a third exemplary embodiment of the present
disclosure, making reference to the drawings. In the third exemplary embodiment, con
figurations of a wireless communication terminal and a control apparatus are different
from the exemplary embodiments described above.
[0071] The third exemplary embodiment illustrates an example where the present invention
is implemented by improving technology known as OpenFlow, which is a centrally
controlled network architecture.
[0072] Referring to FIG. 9 and FIG. 10, a description is given concerning the OpenFlow
technology. In OpenFlow, communication is recognized as end-to-end flow, and path
control, failure recovery, and load balancing are executed in flow units. FIG. 9 shows
an outline of a communication system configured by OpenFlow technology. It is to be
noted that that a flow is, for example, a sequence of communication packet groups
having a prescribed attribute. An OpenFlow Switch 600 is a network switch that uses
the OpenFlow technology. An OpenFlow Controller 700 is an information processing
device that controls the OpenFlow Switch 600.
[0073] The OpenFlow Switch 600 communicates with the OpenFlow Controller via a
Secure Channel 701 provided between the OpenFlow Switch 600 and the OpenFlow
Controller 700. The OpenFlow Controller 700 configures a Flow Table 601 of the
OpenFlow Switch 600, via the Secure Channel 701. It is to be noted that the Secure
Channel 701 is a communication path in which a measure has been taken to prevent in
terception or falsification of communication between a switch and a controller.
[0074] FIG. 10 shows a configuration example of respective entries (flow entries) of the
Flow Table 601. A flow entry is configured by a matching rule for matching in
formation (for example, destination IP address, VLAN ID, or the like) included in a
header of a packet received by the switch, statistical information (Counters) which is
statistical information for each packet flow, and Instructions that specify a processing
method of a packet matching a matching rule.
[0075] On receiving a packet, the OpenFlow Switch 600 refers to the Flow Table 601. The
OpenFlow Switch 600 searches for a flow entry matching the header information of a
received packet. In a case where an entry matching the header information of the
received packet is retrieved, the OpenFlow Switch 600 processes the received packet
in accordance with a processing method defined in an instruction field of the retrieved
entry. In the processing method are, for example, "received packet is forwarded from a
prescribed port", "received packet is dropped", "part of header of received packet is
rewritten, to be forwarded from a prescribed port", or the like.
[0076] On the other hand, in a case where an entry matching the header information of the
received packet is not found, the OpenFlow Switch 600, for example, forwards the
received packet to the OpenFlow Controller 700, via the Secure Channel 701. By
forwarding the received packet, the OpenFlow Switch 600 requests configuration of a
flow entry defining a processing method for the received packet, with respect to the
controller.
[0077] The OpenFlow Controller 700 determines a processing method for the received
packet, and configures a flow entry including the determined processing method in the
Flow Table 601. Thereafter, the OpenFlow Switch 600 processes the received packet
and subsequent packets belonging to the same flow, according to the configured flow
entry.
[0078] FIG. 11 shows an example of a communication system in the third exemplary em
bodiment of the present invention, in which the OpenFlow technology described above
is improved.
[0079] A forwarding apparatus 500 includes a function of the OpenFlow Switch 600. The
network 300 is a communication network including at least some of the forwarding ap
paratuses 500. A control apparatus 200 includes a function of the OpenFlow Controller
700.
[0080] A wireless communication terminal 100 includes a function corresponding to the
OpenFlow Switch 600. It is to be noted that the function corresponding to the
OpenFlow Switch 600 may be implemented by either hardware or software. The
wireless communication terminal 100 is a device having a communication function,
such as a mobile telephone, a personal computer, a mobile router, or the like.
[0081] FIG. 12 is a diagram showing a configuration example of the wireless commu
nication terminal 100. FIG. 12 shows a configuration including a plurality of ap
plication units # 1 to #N 101, a protocol stack unit 102, a packet forwarding function
unit 103, a plurality of ports 104, and a plurality of communication interfaces 105.
[0082] The packet forwarding function unit 103 includes some of the function corre
sponding to the OpenFlow Switch 600. The packet forwarding function unit 103 has a
plurality of the ports 104. In the example of FIG. 12, the packet forwarding function
unit 103 has N (N is an integer) ports 104. Each of the communication interfaces 105 is
associated with at least one of the plurality of ports 104, for example. The packet
forwarding function unit 103 transmits/receives data via the ports 104.
[0083] In the wireless communication terminal 1, a plurality of applications (application unit
# 1 to #N 101) are operating. The applications communicate with the network 300 via a
RAT 4.
[0084] When an application transmits communication data to the network 300, the commu
nication 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 a communication
interface 105 via the packet forwarding function unit 103.
[0085] The packet forwarding function unit 103 forwards the packet from a port 104 in ac
cordance with a packet processing rule (that is, a flow entry) set by the control
apparatus 200. The packet forwarded from the port 104 is transmitted to an access
network of a RAT corresponding to this interface via any of the communication in
terfaces 105. A packet received from the access network of the RAT by the commu
nication interface 105 is sent to an application via a port 104.
[0086] FIG. 13 shows a configuration example of the packet forwarding function unit 103.
FIG. 13 shows a configuration including a monitoring unit 111, a notification unit 112,
a communication 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 DB 135.
[0087] The communication unit 130 communicates with the control apparatus 200. In order
for the packet forwarding function unit 103 to receive a packet processing rule
transmitted from the control apparatus 200, for example, the communication unit 130
sets a Secure Channel 701 with the control apparatus 200. The communication unit
130, for example, makes a request for a packet processing rule to the control apparatus
2, via the Secure Channel 701 that has been set.
[0088] The communication unit 130 passes the packet processing rule received from the
control apparatus 2 to the processing rule management unit 134. The processing rule
management unit 134 stores the packet processing rule received from the control
apparatus 200 in the processing rule DB 135.
[0089] The processing unit 131 performs processing such as packet forwarding or rewriting
of a packet header part in accordance with the packet processing rule that is set by the
control apparatus 200. The search unit 136 searches for a packet processing rule
matching the packet, among the packet processing rules stored in the processing rule
DB 135. The search unit 136, for example, checks matching rules of the packet
processing rules and packet content, and retrieves a processing rule including a
matching rule that matches the packet content. In a case where a processing rule
matching the packet is not stored in the processing rule DB 135, for example, the
search unit 136 notifies the communication unit 130, and the communication unit 130
makes a request for a packet processing rule to the control apparatus 200. It is to be
noted that the configuration of the packet processing rule is the same as the con
figuration shown in FIG. 10.
[0090] A processing execution unit 137 processes the packet in accordance with a
processing method defined in the packet processing rule retrieved by the search unit
136. For example, the processing execution unit 137 executes a process of forwarding
a packet from a prescribed port 104, or a process of rewriting the packet content.
[0091] The monitoring unit 111 and the notification unit 112 have functions the same as the
exemplary embodiments described above.
[0092] The access management unit 113 manages connection of the communication
interface 105 and the RAT 4, using the access management DB 133. The access
management DB 133, for example, holds a correspondence relationship between the
communication interface 105 currently used by the wireless communication terminal
100, and a RAT to which an interface being used is connected. In a case where the
communication interface being used is switched by an instruction from the control
apparatus 200, the access management unit 113 updates the access management DB
133. It is to be noted that the access management DB 133 may also manage in
formation of a connection point (for example, a WiFi access point or the like) of a
RAT to which the communication interface is connected.
[0093] As described above, each of the communication interfaces 105 is associated with at
least one of the plurality of ports 104. Therefore, the access management unit 113
manages connection relationships between the communication interfaces 105 and the
ports 104, using the access management DB 113. The access management DB 133
holds correspondence relationships between the communication interfaces 105 and the
ports 104. The access management DB 133 may hold correspondence relationships
between the communication interfaces 105 currently being used and the ports corre
sponding with those interfaces. In a case where the access management unit 113
switches the communication interface being used by an instruction from the control
apparatus 200, the port being used by the packet forwarding function unit 103 is also
changed. Accompanying the switching of the communication interface, in a case where
the port being used by the packet forwarding function unit 103 changes, the access
management unit 113 updates the access management DB 133. It is to be noted that the
access management DB 133 may manage correspondence relationships between ports
and connection points of a RAT to which the communication interface is connected.
[0094] The access management unit 113 refers to the access management DB 133 and
transmits correspondence relationships between the ports 104 and the communication
interfaces 105, and the port 104 being used, to the control apparatus 200. The port 104
being used is a port 104 corresponding to the communication interface 105 being used
by the wireless communication terminal 100. The control apparatus 200 comprehends
a characteristic of the port 104 and the usage state of the port 104, by receiving this in
formation. The access management unit 113 transmits this information, for example, in
a case of a request being made by the control apparatus 200.
[0095] The OpenFlow technology described above has a function (Port Status) that notifies a
port state of a switch to a controller, and a function (Feature Request/Reply) that
notifies a switch characteristic to the controller. In a case of notifying correspondence
relationships between the ports 104 and the communication interfaces 105, and status
information, or the like, to the control apparatus 200, the access management unit 113
and the notification unit 112 may use these functions.
[0096] The wireless communication terminal 100 may be provided with a function to
download a program module having a function equivalent to the packet forwarding
function unit 103. The wireless communication terminal 100 may use the downloaded
program module as the packet forwarding function unit 103.
[0097] The forwarding apparatus 500 that forwards a packet by the network 300, outside of
the monitoring unit 111, the notification unit 112, the access management unit 132, and
the access management DB 133, has a configuration the same as the packet forwarding
function unit 103 of the wireless communication terminal 100 described above. The
forwarding apparatus 500 processes a packet passing through the network 300 in ac
cordance with a packet processing rule that is set by the control apparatus 200.
[0098] FIG. 14 shows a configuration example of the control apparatus 200. Referring to
FIG. 14, a configuration is shown that includes a node communication unit 201, a
control message processing unit 202, a calculation unit 203, a topology management
unit 204, a location management unit 205, a policy DB 206, a DB management unit
207, a processing rule DB 208, and a packet forwarding function management unit
209. It is to be noted that FIG. 14 is an example, and the configuration of the control
apparatus 200 is not limited to FIG. 14.
[0099] The processing rule DB 208 stores a packet processing rule for setting the wireless
communication terminal 100 and the forwarding apparatus 500. It is to be noted that
the configuration of the packet processing rule is the same as the configuration shown
in FIG. 10.
[0100] The node communication unit 201 communicates with the wireless communication
terminal 100 and the forwarding apparatus 500. The node communication unit 201
forwards status information received from the notification unit 112 of the wireless
communication terminal 100, to the calculation unit 203.
[0101] The topology management unit 204 manages network topology of the network 300,
based on connection relationships of the forwarding apparatuses 500 collected via the
node communication unit 201.
[0102] The location management unit 205 manages the location of the wireless commu
nication terminal 100 in the network topology of the network 300.
[0103] The packet forwarding function management unit 209 manages information (for
example, correspondence relationships of the ports 104 and the communication in
terfaces 105, or the port 104 that is being used by the wireless communication terminal
100) transmitted from the access management unit 113 of the wireless communication
terminal 100. By the packet forwarding function management unit 209, the control
apparatus 200 comprehends the state of the communication interfaces 105 and the
ports 104.
[0104] The calculation unit 203 determines a packet forwarding path based on the network
topology and packet processing executed by the forwarding apparatuses 500 in the
forwarding path. That is, the calculation unit 203 calculates the packet forwarding path
and determines a packet processing rule corresponding to the forwarding path.
[0105] The calculation unit 203 determines a RAT to which the wireless communication
terminal 100 connects, based on the policy DB 206 and status information transmitted
from the wireless communication terminal 100. A method of determining the RAT by
the calculation unit 203 is the same as the exemplary embodiments described above.
The configuration of the policy DB 206 may be the same as the configuration
examples shown in FIG. 5 to FIG. 8.
[0106] The DB management unit 207 records the packet processing rule determined by the
calculation unit 203 in the processing rule DB 208. The DB management unit 207
transmits the packet processing rule to the forwarding apparatus 500 and the wireless
communication terminal 100 in response to a request to transmit the packet processing
rule from the forwarding apparatus 500 or the wireless communication terminal 100.
[0107] The control message processing unit 202 analyzes a control message (for example, a
request to set a packet processing rule, a request to determine a RAT based on status
information, or the like) received from the forwarding apparatus 500 or the wireless
communication terminal 100, and performs processing corresponding to the control
message. The control message processing unit 202 generates a message (for example, a
message for setting a packet processing rule, or the like) to be transmitted to the
forwarding apparatus 500 or the wireless communication terminal 100. The control
message processing unit 202 transmits an instruction to connect with a RAT de
termined by the calculation unit 203, to the wireless communication terminal 100.
[0108] In order to instruct the wireless communication terminal 100 to connect to the de
termined RAT, the calculation unit 203 may use a message that changes a corre
spondence relationship between the communication interface 105 and the port 104.
The calculation unit 203 refers to the packet forwarding function management unit
209, comprehends the correspondence relationship between the communication
interface 105 and the port 104, and generates a message changing this correspondence
relationship. The control message processing unit 202 transmits this message to the
wireless communication terminal 100. The wireless communication terminal 100 that
receives the message associates the port 104 with the communication interface 105
corresponding to the RAT indicated in the message. By this action, the wireless com
munication terminal 100 can switch the connected RAT in accordance with an in
struction from the control apparatus 200. It is to be noted that the abovementioned
OpenFlow technology has a function that transmits a message (Port Modification
Message) changing the setting of a port of a switch. In a case of giving an instruction
to switch the RAT to the wireless communication terminal 100, the control apparatus
200 may use this Port Modification Message.
[0109] In order to instruct the wireless communication terminal 100 to connect to the de
termined RAT, the calculation unit 203 may use a packet processing rule corre
sponding to switching of the RAT. The control message processing unit 202 transmits
this packet processing rule to the wireless communication terminal 100. The c al
culation unit 203, for example, uses the packet processing rule when switching RAT
for each communication flow. For example, the packet processing rule specifies a
processing method to forward a packet belonging to a flow for Web communication, to
the port 104 associated with a communication interface 105 corresponding to a
WLAN.
[0110] FIG. 15 is a sequence diagram showing an operational example of the third
exemplary embodiment. FIG. 15 is an example, and operations of the present invention
are not limited to those of FIG. 15.
[0111] Referring to FIG. 15, the packet forwarding function unit 103 of the wireless communication
terminal 100 establishes a link with a prescribed RAT (for example,
UTRAN 4-1) (step S101). The packet forwarding function unit 103, for example, e s
tablishes a link with the prescribed RAT when operation is started (for example, when
a power supply is turned on). The wireless communication terminal 100 establishes a
link with this RAT by a communication interface 105 corresponding to the prescribed
RAT. The prescribed RAT, for example, is a communication line of a network operator
to which the wireless communication terminal 100 is subscribed, and is a RAT that
attempts to establish a link when the wireless communication terminal 100 is activated.
[0112] The packet forwarding function unit 103 sets a control channel with the control
apparatus 200, via the RAT for which the link is established (step S102). The packet
forwarding function unit 103 communicates with the control apparatus 200 via the
control channel. The control channel, for example, is the Secure Channel 701 of the
OpenFlow technology described above.
[01 13] The packet forwarding function unit 103 monitors status information by using r e
spective communication interfaces 105 (step S103). The packet forwarding function
unit 103 may monitor the status information by using all of the communication in
terfaces 105, or may monitor the status information by using an arbitrarily selected
communication interface 105. In the example of FIG. 15, the packet forwarding
function unit 103 monitors a RAT that can be used by the wireless communication
terminal 100, as the status information. The packet forwarding function unit 103
detects UTRAN 4-1 and WLAN 4-2, as useable RATs.
[0114] On receiving a RAT detection result, the packet forwarding function unit 103 notifies
the control apparatus 200 of information related to the detected RAT as status in
formation (monitoring result) (step S103). In the example of FIG. 15, the packet
forwarding function unit 103 notifies the control apparatus 200 of information related
to the UTRAN 4-1 and WLAN 4-2, as the status information.
[0115] The control apparatus 200 determines the RAT to which the wireless communication
terminal 100 connects, based on the received status information (step S106), and
instructs the wireless communication terminal 100 to connect to the determined RAT
(step S107). In the example of FIG. 15, the control apparatus 200 determines the
WLAN 4-2 as the RAT to which the wireless communication terminal 100 connects.
[0116] The packet forwarding function unit 103 switches the communication interface 105
in accordance with an instruction from the control apparatus 200 (step S108). In the
example of FIG. 15, the packet forwarding function unit 103 switches from a commu
nication interface 105 for UTRAN, to a communication interface 105 for WLAN.
[01 17] As described above, according to the present exemplary embodiment, by applying
the OpenFlow technology it is possible to implement detailed control using the
wireless communication terminal 100 that has a simple configuration.
[0118] (Fourth Exemplary Embodiment)
Next, a description is given of a fourth exemplary embodiment of the present
disclosure, making reference to the drawings. A communication system of the fourth
exemplary embodiment is similar to examples shown in FIG. 1 and FIG. 11. Con
figuration examples of a wireless communication terminal and a control apparatus are
similar to examples shown in FIG. 2, FIG. 4, FIG. 12, FIG. 13, and FIG. 14.
[0119] In the fourth exemplary embodiment, the wireless communication terminal activates
a communication interface in accordance with an instruction from the control
apparatus. The communication interface operation is stopped until being activated
based on the instruction from the control apparatus.
[0120] When the communication interface monitors status information, the wireless commu
nication terminal consumes power. Therefore, when monitoring is performing
frequently, the power consumption of the wireless communication terminal increases.
However, in the fourth exemplary embodiment, since operation of the communication
interface is stopped until instructed by the control apparatus, it is possible to curtail
excessive monitoring operations by the communication interface. Accordingly, it is
possible to reduce the power consumption of the wireless communication terminal.
[0121] Referring to FIG. 16, a description is given of the fourth exemplary embodiment.
FIG. 16 is a sequence diagram showing an operational example of the fourth
exemplary embodiment. It is to be noted that FIG. 16 is an example, and operations of
the present invention are not limited to those of FIG. 16.
[0122] In FIG. 16, a description is given using the wireless communication terminal 1
shown in FIG. 2, and the control apparatus 2 shown in FIG. 4, but the wireless commu
nication terminal 100 and the control apparatus 200 described in the third exemplary
embodiment may also be used.
[0123] The wireless communication terminal 1 establishes a link with a prescribed RAT (for
example, UTRAN 4-1) (step S201). The wireless communication terminal 1, for
example, establishes a link with the prescribed RAT when operation is started (for
example, when a power supply is turned on). The wireless communication terminal 1
establishes a link with this RAT by a communication interface 10 corresponding to the
prescribed RAT. The prescribed RAT, for example, is a communication line of a
network operator to which the wireless communication terminal 1 is subscribed, and is
a RAT that attempts to establish a link when the wireless communication terminal 1 is
activated. In FIG. 16 the prescribed RAT is an UTRAN.
[0124] As shown in FIG. 16, the communication interface 10 corresponding to the UTRAN
is operating (step S202), but operation of a communication interface 10 corresponding
to a WLAN is stopped. Therefore, status monitoring by the wireless communication
terminal 1 is executed via the communication interface 10 corresponding to the
UTRAN, but monitoring by the communication interface corresponding to the WLAN
is not executed. In FIG. 16, the wireless communication terminal 1, for example,
monitors information related to the location of the wireless communication terminal 1
by the communication interface 10 corresponding to the UTRAN.
[0125] The wireless communication terminal 1 notifies the control device 2 of information
related to the location of the wireless communication terminal 1, as status information
(step S203).
[0126] The control apparatus 2 determines a RAT to which the wireless communication
terminal 1 connects, based on the received status information (step S204). The control
apparatus 2, for example, determines the RAT by a method described with reference to
FIG. 8. The control apparatus 2 refers to a policy DB 22 of FIG. 8, from information
related to the location of the wireless communication terminal 1, and selects a RAT to
which the terminal connects, from RATs that can be used by the wireless commu
nication terminal 1. In FIG. 16, the control apparatus 2 determines the WLAN 4-2 as
the RAT to which the wireless communication terminal 1 connects.
[0127] The control apparatus 2 instructs the wireless communication terminal 1 to activate
the communication interface 10 corresponding to the determined RAT (step S205). An
access management unit 113 of the wireless communication terminal activates the
communication interface in response to the instruction received from the control
apparatus 2 (step S206). The wireless communication terminal 1 activates the commu
nication interface 10, for example, by changing an operation setting of "OFF" to "ON".
The communication interface with an operation setting of "OFF" does not execute op
erations such as status monitoring or the like. By the operation setting being made
"ON", the communication interface is activated. By the operation setting being made
"ON", the communication interface can perform operations such as status monitoring
or connecting with a RAT. It is to be noted that the control apparatus 2 may also
instruct that operation of a communication interface not used by the wireless commu
nication terminal 1 be stopped.
[0128] The wireless communication terminal 1 connects to a RAT by the communication
interface 10 that has been activated (step S207).
[0129] According to the present exemplary embodiment as described above, in addition to
effects of the abovementioned exemplary embodiments it is possible to reduce the
power consumption of the wireless communication terminal. It is to be noted that when
the communication interface indicated by the control apparatus 2 is activated, the
wireless communication terminal 1 may stop operation of unused interfaces. In this
way, it is possible to further reduce the power consumption of the wireless commu
nication terminal 1.
[0130] (Fifth Exemplary Embodiment)
Next, a description is given of a fifth exemplary embodiment of the present disclosure,
making reference to the drawings. A communication system of the fifth exemplary em
bodiment is similar to examples shown in FIG. 1 and FIG. 11. Configuration examples
of a wireless communication terminal and a control apparatus are similar to examples
shown in FIG. 2, FIG. 4, FIG. 12, FIG. 13, and FIG. 14.
[0131] In the fifth exemplary embodiment, a RAT to which the wireless communication
terminal connects is determined based on a characteristic of the wireless commu
nication terminal. The characteristic of the wireless communication terminal, for
example, is movement history, communication history, or the like, of the wireless com
munication terminal. Otherwise, a characteristic of the wireless communication
terminal can use something that changes along with movement of the wireless commu
nication terminal.
[0132] Referring to FIG. 17, a description is given of an operational example where the
control apparatus selects a RAT based on the movement history of the wireless com
munication terminal. FIG. 17 is a diagram for describing an example in which the RAT
is determined based on the movement history of the wireless communication terminal.
A policy DB of the control apparatus manages the movement history of the wireless
communication terminal by a database of a structure exemplified in FIG. 17.
[0133] A monitoring unit 111 of the wireless communication terminal periodically monitors
the movement history of the wireless communication terminal, and a notification unit
112 notifies the control apparatus of a monitoring result as status information. The
control apparatus can build the database exemplified in FIG. 17 in the policy DB,
based on received status information.
[0134] From the movement history shown in FIG. 17, the control apparatus, for example,
can estimate the period of time for which the wireless communication terminal remains
at a prescribed location. In a case where the wireless communication terminal remains
at a prescribed location for a specific period of time, the control apparatus instructs the
wireless communication terminal to connect to a RAT with low communication
charges or a RAT with the best communication state, among usable RATs at the
prescribed location where the terminal remains during the specific period of time. For
example, the control apparatus estimates the period of time it remains in an area where
a WiFi hotspot exists from the policy DB 22, and instructs the wireless communication
terminal to attempt to connect to the WiFi hotspot in this time period. By this type of
operation, the wireless communication terminal can automatically connect to an ap
propriate RAT.
[0135] From the movement history shown in FIG. 17, the control apparatus, for example,
can estimate a time period in which the location frequently changes at short time
intervals. In a case where the wireless communication terminal moves at high speed in
a car or train, it is assumed that the location changes frequently at short time intervals.
When a connected RAT frequently changes in accordance with change in location, it is
assumed that communication is frequently cut off for the wireless communication
terminal. Therefore, in a case where the location changes frequently at short time
intervals, the control apparatus can select a RAT that can be continuously used even if
the location changes, and it is possible to prevent communication being unnecessarily
being cut off for the wireless communication terminal. For example, the control
apparatus instructs the wireless communication terminal 1 to use an UTRAN with
which stable communication is possible during weekday morning commuting periods.
[0136] As described above, by selecting the RAT based on the movement history of the
wireless communication terminal, it is possible to provide a comfortable commu
nication environment to the wireless communication terminal user.
[0137] Next, referring to FIG. 18, a description is given of an operational example where the
control apparatus selects a RAT based on communication history of the wireless com
munication terminal. The policy DB of the control apparatus manages the commu
nication history of the wireless communication terminal by a database of a structure
exemplified by FIG. 18.
[0138] The monitoring unit 111 of the wireless communication terminal periodically
monitors the communication history of the wireless communication terminal, and a no
tification unit 112 notifies the control apparatus of a monitoring result as status in
formation. The control apparatus can build the database exemplified in FIG. 18 in the
policy DB, based on received status information.
[0139] From the communication history shown in FIG. 18, the control apparatus, for
example, can estimate a time period in which the wireless communication terminal
communicates continuously with a large communication amount. For example, the
control apparatus can estimate a time period when the wireless communication
terminal continuously carries out communication of video streaming or the like. The
control apparatus, for example, selects a RAT having a wide communication band or a
RAT with little congestion in a time period when the wireless communication terminal
carries out a large amount of communication. In a case where the wireless commu
nication terminal continues to carry out a large amount of communication for a
prescribed period or longer, the control apparatus can select a RAT with a narrow com
munication band and can limit communication of the wireless communication
terminal.
[0140] From the communication history shown in FIG. 18, the control apparatus, for
example, can estimate a time period in which the communication amount by the
wireless communication terminal is low. In the example of FIG. 18, a time period
where communication flow is "None" is a time period where there is no communication
by the wireless communication terminal. The control apparatus, for example,
instructs the wireless communication terminal to stop operation of a communication
interface corresponding to a prescribed RAT in the time period where there is little
communication by the wireless communication terminal. By this action, since it is
possible to curtail unnecessary operation such as an operation of scanning RATs by a
communication interface, it is possible to reduce the power consumption of the
wireless communication terminal.
[0141] According to the present exemplary embodiment as described above, it is possible to
instruct the selection of a RAT that is appropriate to a user access environment
estimated from the movement history or the communication history of the wireless
communication terminal, or to control the power supply of an interface.
[0142] (Sixth Exemplary Embodiment)
Next, a description is given of a sixth exemplary embodiment of the present
disclosure, making reference to the drawings. A communication system of the sixth
exemplary embodiment is similar to examples shown in FIG. 1 and FIG. 11.
[0143] In the sixth exemplary embodiment, in a case where the consent of a user of a
wireless communication terminal is obtained, a communication interface is switched in
accordance with an instruction from a control apparatus 2. An assumption is also made
that the communication interface specified in the instruction from the control apparatus
2 is opposed to the intention of the user of the wireless communication terminal. In the
sixth exemplary embodiment, the intention of the user of the wireless communication
terminal is taken into consideration to perform switching of the communication
interface.
[0144] In the sixth exemplary embodiment a description is given making reference to the
wireless communication terminal 1 exemplified in FIG. 2, and the control apparatus 2
exemplified in FIG. 4, but the wireless communication terminal and the control
apparatus may be configured as described in the third exemplary embodiment.
[0145] FIG. 19 is a diagram showing a configuration example of a policy DB 22 of the
present exemplary embodiment. The policy DB 22 stores Admission Information in
dicating whether or not users of respective wireless communication terminals 1
consent to switching of communication interfaces in accordance with an instruction of
the control apparatus 2, for each identifier of the wireless communication terminals 1.
It is to be noted that the identifiers of the wireless communication terminals 1 are, for
example, IMSI (International Mobile Subscriber Identity) or the like.
[0146] The control apparatus 2, for example, obtains the Admission Information in advance
from the wireless communication terminal 1. For example, a communication operator
records the Admission Information in the policy DB 22, based on a subscription of the
user of the wireless communication terminal 1. For example, the user of the wireless
communication terminal 1 may notify the control apparatus 2 of Admission In
formation using the wireless communication terminal 1. The Admission Information of
the policy DB 22 may be configured so as to enable change as appropriate by the user
of the wireless communication terminal 1.
[0147] In a case of the user giving consent (for example, a case where the Admission In
formation is "Yes"), the control unit 2 1 of the control apparatus 2 gives an instruction
of a RAT to be used, to the wireless communication terminal 1, and a communication
interface is instructed to the wireless communication terminal 1. In a case of the user
not giving consent (for example, a case where the Admission Information is "No"), the
control unit 2 1 does not transmit an instruction to the wireless communication terminal
1.
[0148] An example is shown where the control apparatus 2 judges whether or not to give an
instruction to the wireless communication terminal 1 based on the Admission In
formation. This is an example, however, and the wireless communication terminal 1
may also judge whether or not to follow an instruction received from the control
apparatus 2.
[0149] For example, on receiving an instruction from the control apparatus 2, an access
management unit 113 of the wireless communication terminal 1 displays a dialog for
confirming the user's consent on a display of the wireless communication terminal 1. In
accordance with the dialog, the user inputs whether or not the user consents to
switching of communication interface. In a case where the user consents, the access
management unit 113 of the wireless communication terminal 1 switches the commu
nication interface in accordance with the instruction from the control apparatus 2.
[0150] As described above, according to the present exemplary embodiment, it is possible to
implement RAT switching, giving consideration to the intention of the user.
[0151] Descriptions of the respective exemplary embodiments of the present disclosure have
been given above, but the present disclosure is not limited to the abovementioned r e
spective exemplary embodiments, and modifications, substitutions, and adjustments
are possible. Furthermore, the present disclosure may be implemented by arbitrarily
combining the respective exemplary embodiments. Namely, the present disclosure
includes various types of transformation and modification or variation that could be
conceived by a person skilled in the art, in accordance with the entire disclosure
including the scope of the claims and to technical concepts thereof.
Finally, preferred modes of the present invention are summarized.

(See the wireless communication terminal according to a first aspect described
above.)

The wireless communication terminal according to the first mode, wherein the commu
nicating means (unit) activates a communication interface corresponding to the in
structed wireless access system in accordance with an instruction from the control
apparatus, and communicates using the activated communication interface.

The wireless communication terminal according to the first or second mode, further
comprising means (unit) for notifying the control apparatus of the status of the wireless
communication terminal, which changes along with movement of the wireless commu
nication terminal.

The wireless communication terminal according to any one of the first to third modes,
further comprising means (unit) for switching a communication interface for each
communication flow, based on an instruction transmitted from the control apparatus.

The wireless communication terminal according to any one of the first to fourth modes,
further comprising means (unit) for stopping operation of at least one communication
interface, based on an instruction of the control apparatus.

The wireless communication terminal according to any one of the first to fifth modes,
wherein the receiving means (unit) additionally receives information related to a
connection apparatus for connecting by the wireless access system determined by the
control apparatus, from the control apparatus; and the communicating means (unit)
communicates via the connection apparatus, by the communication interface corre
sponding to the instructed wireless access system.

The wireless communication terminal according to any one of the first to sixth modes,
wherein the receiving means (unit) receives an instruction from the control apparatus,
the instruction including a wireless access system determined by the control apparatus
based on information related to the location of the wireless communication terminal,
and the communicating means (unit) communicates using a communication interface
corresponding to the instructed wireless access system.

The wireless communication terminal according to any one of the first to seventh
modes, wherein the receiving means (unit) receives an instruction including a wireless
access system determined based on at least one of: movement history of the wireless
communication terminal or communication history of the wireless communication
terminal.

The wireless communication terminal according to any one of the first to eighth
modes, wherein the communicating means (unit) communicates using a commu
nication interface corresponding to an instruction from the control apparatus, in a case
where a user of the wireless communication terminal has consented.

The wireless communication terminal according to any one of the first to ninth modes,
furthermore comprising a packet processing means (unit) for making a request to the
control apparatus for a processing rule for processing a packet belonging to a
prescribed communication flow, and processing the packet in accordance with the
processing rule that is set by the control apparatus in response to the request; wherein
the packet processing means (unit) receives a processing rule prescribing switching of
a communication interface in accordance with a communication flow, from the control
apparatus, and processes the packet in accordance with the processing rule.

(See the communication system according to a second aspect described above.)

The communication system according to the eleventh mode, wherein the commu
nicating means (unit) of the wireless communication terminal activates a commu
nication interface corresponding to the instructed wireless access system in accordance
with the instruction from the control apparatus, and communicates using the activated
communication interface.

The communication system according to the eleventh or twelfth mode, wherein the
wireless communication terminal further comprises means (unit) for notifying the
control apparatus of the status of the wireless communication terminal, which changes
along with movement of the wireless communication terminal.

The communication system according to any one of the eleventh to thirteenth nodes,
wherein the control apparatus comprises means (unit) for determining a wireless access
system to which the wireless communication terminal connects, for each commu
nication flow; and the wireless communication terminal further comprises means (unit)
for switching a communication interface for each communication flow, based on an in
struction transmitted from the control apparatus.

The communication system according to any one of the eleventh to fourteenth modes,
wherein the wireless communication terminal further comprises means (unit) for
stopping operation of at least one communication interface not used in communication,
based on an instruction transmitted from the control apparatus.

The communication system according to any one of the eleventh to fifteenth modes,
wherein the control apparatus further comprises means (unit) for transmitting in
formation related to a connection apparatus for connecting to a determined wireless
access system, to the wireless communication terminal; and the communicating means
(unit) of the wireless communication terminal communicates via the connection
apparatus by a communication interface corresponding to the instructed wireless access
system.

The communication system according to any one of the eleventh to sixteenth modes,
wherein the control apparatus further comprises means (unit) for determining a
wireless access system based on information related to the location of a wireless com
munication terminal; the receiving means (unit) of the wireless communication
terminal receives an instruction including a wireless access system determined by the
control apparatus; and the communicating means (unit) of the wireless communication
terminal communicates using a communication interface corresponding to the in
structed wireless access system.

The communication system according to any one of the eleventh to seventeenth modes,
wherein the control apparatus further comprises means (unit) for determining a
wireless access system based on at least one of: movement history of the wireless com
munication terminal or communication history of the wireless communication
terminal; the receiving means (unit) of the wireless communication terminal receives
an instruction including the wireless access system determined by the control
apparatus; and the communicating means (unit) of the wireless communication
terminal communicates using a communication interface corresponding to the in
structed wireless access system.

The communication system according to any one of the eleventh to eighteenth modes,
wherein the communicating means (unit) of the wireless communication terminal uses
a communication interface corresponding to an instruction from the control apparatus,
in a case where a user has consented.

The communication system according to any one of the eleventh to nineteenth modes,
wherein the wireless communication terminal comprises a packet processing means
(unit) for making a request to the control apparatus for a processing rule for processing
a packet belonging to a prescribed communication flow, and processing the packet in
accordance with the processing rule that is set by the control apparatus in response to
the request; and receives a processing rule prescribing switching of a communication
interface in accordance with a communication flow from the control apparatus, and
processes the packet in accordance with the processing rule.

(See the control apparatus according to a third aspect described above.)

The control apparatus according to the twenty-first mode, further comprising means
(unit) for transmitting an instruction to activate a communication interface corre
sponding to the determined wireless access system, to the wireless communication
terminal.

The control apparatus according to the twenty-first or twenty-second mode, further
comprising means (unit) for determining a wireless access system to which the
wireless communication terminal connects, for each communication flow.

The control apparatus according to any one of the twenty-first to twenty-third modes,
further comprising means (unit) for transmitting an instruction to the wireless commu
nication terminal to stop operation of at least one communication interface corre
sponding to a wireless access system not used in communication.

The control apparatus according to any one of the twenty-first to twenty-fourth modes,
wherein the means (unit) for transmitting transmits information related to a connection
apparatus for connecting to the determined wireless access system, to the wireless
communication terminal.

The control apparatus according to any one of the twenty-first to twenty-fifth modes,
wherein the determining means (unit) determines a wireless access system to be used
by a wireless communication terminal based on information related to the location of
the wireless communication terminal.

The control apparatus according to any one of the twenty-first to twenty-sixth modes,
wherein the determining means (unit) determines a wireless access system to be used
by the wireless communication terminal based on at least one of: movement history of
the wireless communication terminal or communication history of the wireless com
munication terminal.

The control apparatus according to any one of the twenty-first to twenty- seventh
modes, wherein the transmitting means (unit) transmits the instruction to the wireless
communication terminal in a case where a user of the wireless communication terminal
has consented.

The control apparatus according to any one of the twenty-first to twenty-eighth modes,
wherein the control apparatus transmits a processing rule prescribing switching of a
communication interface in accordance with a communication flow, to a wireless com
munication terminal having a packet processing means (unit) for making a request to
the control apparatus for a processing rule for processing a packet belonging to a
prescribed communication flow, and processing the packet in accordance with the
processing rule that is set by the control apparatus in response to the request.

(See the communication method according to a fourth aspect described above.)

(See the program according to a fifth aspect described above.)
[0152] The respective disclosures of the Patent Literature and Non Patent Literature
described above are hereby incorporated by reference into this application. The
exemplary embodiments and examples may be changed and adjusted within the
bounds of the entire disclosure (including claims) of the present invention and based
on fundamental technological concepts thereof. Furthermore, a wide variety of com
binations and selections of various disclosed elements (including respective elements
of the respective claims, respective elements of the respective exemplary embodiments
and examples, respective elements of the respective drawings, and the like) is possible
within the scope of the claims of the present invention. That is, it is to be understood
that the present invention includes every type of transformation and modification
(variation) that a person skilled in the art can realize according to the entire disclosure
including the scope of the claims and to technological concepts thereof.
Reference Signs List
[0153] 1 wireless communication terminal
2 control apparatus
3 network
4 RAT
4-1 UTRAN
4-2 to 4-4 WLAN
10 communication interface
11 control unit
12 communication unit
20 communication unit
control unit
policy DB
wireless communication terminal
application unit
protocol stack unit
packet forwarding function unit
port
communication interface
monitoring unit
notification unit
access management unit
communication unit
processing unit
access management unit
access management DB
processing rule management unit
processing rule DB
search unit
processing execution unit
control apparatus
node communication unit
control message processing unit
calculation unit
topology management unit
location management unit
policy DB
DB management unit
processing rule DB
packet forwarding function management unit
network
forwarding apparatus
OpenFlow Switch
1 Flow Table
OpenFlow Controller
1 Secure Channel
PCT7JP2012/007063

Claims
A wireless communication terminal, comprising:
a plurality of communication interfaces each of which corresponds to at
least one of a plurality of wireless access systems;
means for receiving an instruction from a prescribed control apparatus,
said instruction including a wireless access system determined by said
control apparatus based on a status of said wireless communication
terminal, which changes along with movement of said wireless commu
nication terminal; and
means for communicating by using a communication interface corre
sponding to said instructed wireless access system.
The wireless communication terminal according to claim 1, wherein
said communicating means activates a communication interface corre
sponding to said instructed wireless access system in accordance with
an instruction from said control apparatus, and communicates using
said activated communication interface.
The wireless communication terminal according to claim 1 or 2, further
comprising means for notifying said control apparatus of the status of
said wireless communication terminal, which changes along with
movement of said wireless communication terminal.
The wireless communication terminal according to any of claims 1 to 3,
further comprising means for switching a communication interface for
each communication flow, based on an instruction transmitted from
said control apparatus.
The wireless communication terminal according to any of claims 1 to 4,
further comprising means for stopping operation of at least one com
munication interface, based on an instruction of said control apparatus.
The wireless communication terminal according to any of claims 1 to 5,
wherein
said receiving means additionally receives information related to a
connection apparatus for connecting by said wireless access system de
termined by said control apparatus, from said control apparatus; and
said communicating means communicates via said connection
apparatus, by a communication interface corresponding to said in
structed wireless access system.
The wireless communication terminal according to any of claims 1 to 6,
wherein
WO 2013/118209 PCT/JP2012/007063
said receiving means receives an instruction from said control
apparatus, said instruction including a wireless access system de
termined by said control apparatus based on information related to the
location of said wireless communication terminal, and
said communicating means communicates using a communication
interface corresponding to said instructed wireless access system.
[Claim 8] The wireless communication terminal according to any of claims 1 to 7,
wherein said receiving means receives an instruction including a
wireless access system determined based on at least one of: movement
history of said wireless communication terminal or communication
history of said wireless communication terminal.
[Claim 9] The wireless communication terminal according to any of claims 1 to 8,
wherein said communicating means communicates using a commu
nication interface corresponding to an instruction from said control
apparatus, in a case where a user of said wireless communication
terminal has consented.
[Claim 10] The wireless communication terminal according to any of claims 1 to 9,
furthermore comprising:
a packet processing means for making a request to said control
apparatus for a processing rule for processing a packet belonging to a
prescribed communication flow, and processing said packet in ac
cordance with said processing rule that is set by said control apparatus
in response to said request; wherein
said packet processing means receives a processing rule prescribing
switching of a communication interface in accordance with a commu
nication flow, from said control apparatus, and processes said packet in
accordance with said processing rule.
[Claim 11] A communication system, comprising:
a control apparatus that controls wireless access systems to which a
wireless communication terminal connects;
a plurality of communication interfaces each of which corresponds to at
least one of said wireless access systems;
means for receiving an instruction from a prescribed control apparatus,
said instruction including a wireless access system determined by said
control apparatus based on a status of said wireless communication
terminal, which changes along with movement of said wireless commu
nication terminal; and
means for communicating by using a communication interface correWO
2013/118209 PCT/JP2012/007063
sponding to said instructed wireless access system.
[Claim 12] The communication system according to claim 11, wherein said com
municating means of said wireless communication terminal activates a
communication interface corresponding to said instructed wireless
access system in accordance with said instruction from said control
apparatus, and communicates using said activated communication
interface.
[Claim 13] The communication system according to claim 11 or 12, wherein said
wireless communication terminal further comprises means for notifying
said control apparatus of the status of said wireless communication
terminal, which changes along with movement of said wireless commu
nication terminal.
[Claim 14] The communication system according to any of claims 1 1 to 13,
wherein
said control apparatus comprises means for determining a wireless
access system to which said wireless communication terminal connects,
for each communication flow; and
said wireless communication terminal further comprises means for
switching a communication interface for each communication flow,
based on an instruction transmitted from said control apparatus.
[Claim 15] The communication system according to any of claims 11 to 14,
wherein said wireless communication terminal further comprises means
for stopping operation of at least one communication interface not used
in communication, based on an instruction transmitted from said
control apparatus.
[Claim 16] The communication system according to any of claims 1 1 to 15,
wherein
said control apparatus further comprises means for transmitting in
formation related to a connection apparatus for connecting to a de
termined wireless access system, to said wireless communication
terminal; and
said communicating means of said wireless communication terminal
communicates via said connection apparatus, by a communication
interface corresponding to said instructed wireless access system.
[Claim 17] The communication system according to any of claims 11 to 16,
wherein
said control apparatus further comprises means for determining a
wireless access system based on information related to the location of a
WO 2013/118209 PCT/JP2012/007063
wireless communication terminal;
said receiving means of said wireless communication terminal receives
an instruction including a wireless access system determined by said
control apparatus; and
said communicating means of said wireless communication terminal
communicates using a communication interface corresponding to said
instructed wireless access system.
[Claim 18] The communication system according to any of claims 11 to 17,
wherein
said control apparatus further comprises means for determining a
wireless access system based on at least one of: movement history of
said wireless communication terminal or communication history of said
wireless communication terminal;
said receiving means of said wireless communication terminal receives
an instruction including said wireless access system determined by said
control apparatus; and
said communicating means of said wireless communication terminal
communicates using a communication interface corresponding to said
instructed wireless access system.
[Claim 19] The communication system according to any of claims 1 1 to 18,
wherein said communicating means of said wireless communication
terminal uses a communication interface corresponding to an in
struction from said control apparatus, in a case where a user has
consented.
[Claim 20] The communication system according to any of claims 11 to 19,
wherein said wireless communication terminal
comprises a packet processing means for making a request to said
control apparatus for a processing rule for processing a packet
belonging to a prescribed communication flow, and processing said
packet in accordance with said processing rule that is set by said
control apparatus in response to said request; and
receives a processing rule prescribing switching of a communication
interface in accordance with a communication flow from said control
apparatus, and processes said packet in accordance with said processing
rule.
[Claim 21] A control apparatus, comprising:
means for receiving a status of a wireless communication terminal,
which changes along with movement of said wireless communication
PCT7JP2012/007063
terminal;
means for determining a wireless access system to which said wireless
communication terminal connects, based on the received status of said
wireless communication terminal; and
means for transmitting an instruction including said determined
wireless access system, to said wireless communication terminal.
The control apparatus according to claim 21, further comprising means
for transmitting an instruction to activate a communication interface
corresponding to said determined wireless access system, to said
wireless communication terminal.
The control apparatus according to claim 2 1 or 22, further comprising
means for determining a wireless access system to which said wireless
communication terminal connects, for each communication flow.
The control apparatus according to any of claims 2 1 to 23, further
comprising means for transmitting an instruction to said wireless com
munication terminal to stop operation of at least one communication
interface corresponding to a wireless access system not used in commu
nication.
The control apparatus according to any of claims 2 1 to 24, wherein said
means for transmitting transmits information related to a connection
apparatus for connecting to said determined wireless access system, to
said wireless communication terminal.
The control apparatus according to any of claims 2 1 to 25, wherein said
determining means determines a wireless access system to be used by a
wireless communication terminal based on information related to the
location of said wireless communication terminal.
The control apparatus according to any of claims 2 1 to 26, wherein said
determining means determines a wireless access system to be used by
said wireless communication terminal based on at least one of:
movement history of said wireless communication terminal or commu
nication history of said wireless communication terminal.
The control apparatus according to any of claims 2 1 to 27, wherein said
transmitting means transmits said instruction to said wireless commu
nication terminal in a case where a user of said wireless communication
terminal has consented.
The control apparatus according to any of claims 2 1 to 28, wherein said
control apparatus transmits a processing rule prescribing switching of a
communication interface in accordance with a communication flow, to
WO 2013/118209 PCT/JP2012/007063
a wireless communication terminal having a packet processing means
for making a request to said control apparatus for a processing rule for
processing a packet belonging to a prescribed communication flow, and
processing said packet in accordance with said processing rule that is
set by said control apparatus in response to said request.
[Claim 30] A communication method using a wireless communication terminal
including a plurality of communication interfaces corresponding to at
least one of a plurality of wireless access systems;
said method comprising:
receiving, from a prescribed control apparatus, an instruction including
a wireless access system determined by said control apparatus based on
a status of said wireless communication terminal, which changes along
with movement of said wireless communication terminal, and
communicating by using a communication interface corresponding to
said instructed wireless access system.
[Claim 31] A program that executes on a wireless communication terminal
including a plurality of communication interfaces corresponding to at
least one of a plurality of wireless access systems, said program
comprising:
a process of receiving, from a prescribed control apparatus, an in
struction including a wireless access system determined by said control
apparatus based on a status of said wireless communication terminal,
which changes along with movement of said wireless communication
terminal, and
a process of communicating by using a communication interface corre
sponding to said instructed wireless access system.