COMMUNICATION TERMINAL, COMMUNICATION METHOD, COMMUNICATION SYSTEM, AND
PROGRAM
Technical Field
[0001] (Reference to Related Application)
The present invention is based upon and claims the benefit of the priority of Japanese
patent application No. 201 1-190294 filed on September 1st, 201 1, the disclosure of
which is incorporated herein in its entirety by reference thereto.
The present invention relates to a communication terminal, communication method,
communication system, and program, and particularly to a communication terminal,
communication method, communication system, and program in a network centrally
controlled by a control apparatus.
Background
[0002] In recent years, centrally controlled network architectures have been proposed. As an
example of a centrally controlled network architecture, there is a technology called
OpenFlow (refer to Patent Literature 1 and Non Patent Literatures 1 and 2).
[0003] OpenFlow treats communication as an end-to-end flow, and performs path control,
failure recovery, load balancing, and optimization for each flow. An OpenFlow switch
specified in Non Patent Literature 2 comprises a secure channel for communicating
with an OpenFlow controller that corresponds to a control apparatus, and operates
according to a flow table given an appropriate instruction of addition or rewrite by an
OpenFlow controller. In the flow table, a set of a packet matching rule (header fields)
that matches a packet header, flow statistics (Counters), and an action (Actions) that
defines a processing content is defined for each flow (refer to Fig. 11).
[0004] Upon receiving a packet, the OpenFlow switch searches an entry having a matching
rule (refer to the header fields in Fig. 11) that matches the header information of the
received packet in the flow table. When an entry matching the received packet is found
as a result, the OpenFlow switch updates the flow statistics (Counter) and performs the
processing content (packet transmission from a designated port, flooding, discard, etc.)
written in the action field of the entry on the received packet. Meanwhile, when no
entry matching the received packet is found as a result of the search, the OpenFlow
switch forwards the received packet to the OpenFlow controller via the secure channel,
requesting the controller to determine the path of the packet based on the source/
destination of the received packet, receives a flow entry realizing this, and updates the
flow table. As described, the OpenFlow switch forwards packets using entries stored in
the flow table as processing rules.
Citation List
Patent Literature
[0005] PTL 1:WO Publication No. WO2008/095010
Non-Patent Literature
[0006] NPL 1: McKeown, Nick, et al., "OpenFlow: Enabling Innovation in Campus
Networks," [online], [searched on August 16, 2011], the Internet
NPL 2: "OpenFlow Switch Specification" Version 1.1.0 Implemented (Wire Protocol 0
x 02), [online], [searched on August 16, 2011], the Internet
Summary
Technical Problem
[0007] The following analysis is given by the present invention.
[0008] In a centrally controlled network architecture, devices such as switches and routers
constituting the network must establish a control communication channel to a control
apparatus (controller) that centrally controls these devices.
[0009] However, documents listed above (Patent Literature 1, and Non Patent Literatures 1
and 2) do not describe any method for checking an address of the control apparatus in
order to establish the control communication channel. In the related technologies
above, for instance, devices such as switches and routers establish the control commu
nication channel based on an address of the control apparatus statically configured in
these devices.
[0010] Further, devices controlled by the control apparatus may include not only switches
and routers, but also communication terminals in the future. A communication terminal
changes the network it accesses as it changes its location. Each time the network is
changed, the communication terminal needs to change the control apparatus that e s
tablishes the communication channel. However, since the related technologies listed
above do not describe any method for checking an address of the control apparatus, it
is difficult for the communication terminal to change the control apparatus establishing
the communication channel.
[001 1] Therefore, there is a need in the art to make it possible to establish a communication
channel between a control apparatus that centrally controls a network and a commu
nication terminal even when the communication terminal changes the network it
accesses. It is an object of the present invention to provide a communication terminal,
communication system, communication method, and program that can cope with such
need.
Solution to Problem
[0012] According to a first aspect of the present disclosure, there is provided a commu
nication terminal, which communicates with a network including a control apparatus
that generates a processing rule defining a packet processing method, the commu
nication terminal comprising:
request means (unit) that requests an address of the control apparatus when re
questing for establishing a connection to the network;
communication means (unit) that establishes a communication channel to the control
apparatus based on an address acquired by the address request; and
processing means (unit) that processes a packet based on a processing rule
transmitted by the control apparatus via the communication channel.
[0013] According to a second aspect of the present disclosure, there is provided a commu
nication method, in which a communication terminal is used that communicates with a
network including a control apparatus that generates a processing rule defining a
packet processing method, the method comprising:
requesting an address of the control apparatus when requesting for establishing a
connection to the network;
establishing a communication channel to the control apparatus based on an address
acquired by the address request; and
processing a packet based on a processing rule transmitted by the control apparatus
via the communication channel.
[0014] According to a third aspect of the present disclosure, there is provided a commu
nication system comprising:
a network including a control apparatus that generates a processing rule defining a
packet processing method; and
a communication terminal that communicates with the network;
the communication terminal further comprising:
request means (unit) that requests an address of the control apparatus when re
questing for establishing a connection to the network;
communication means (unit) that establishes a communication channel to the control
apparatus based on an address acquired by the address request; and
processing means (unit) that processes a packet based on a processing rule
transmitted by the control apparatus via the communication channel.
[0015] According to a fourth aspect of the present disclosure, there is provided a program
causing a computer built into a communication terminal that communicates with a
network including a control apparatus that generates a processing rule defining a
packet processing method to execute:
requesting an address of the control apparatus when requesting for establishing a
connection to the network;
establishing a communication channel to the control apparatus based on an address
acquired by the address request; and
processing a packet based on a processing rule transmitted by the control apparatus via
the communication channel.
The program may be provided as a program product recorded on a non-transitory
computer-readable storage medium.
Advantageous Effects of Invention
[0016] According to the present disclosure, even when changing the network to access, a
communication terminal is able to establish a communication channel to a control
apparatus that centrally controls the network without resetting the address of the
control apparatus in the communication terminal.
Brief Description of Drawings
[0017] [fig. l]Fig. 1 is a block diagram showing a configuration example of a communication
system having a communication terminal relating to a first exemplary embodiment.
[fig.2]Fig. 2 is a block diagram showing a configuration example of the commu
nication terminal relating to the first exemplary embodiment.
[fig.3]Fig. 3 is a drawing for explaining an operation example of the communication
terminal relating to the first exemplary embodiment.
[fig.4]Fig. 4 is a sequence diagram showing an operation example of the commu
nication terminal relating to the first exemplary embodiment.
[fig.5]Fig. 5 is a sequence diagram showing an operation example of the commu
nication terminal relating to the first exemplary embodiment.
[fig.6]Fig. 6 is a block diagram showing a configuration example of a communication
system having a communication terminal relating to a fourth exemplary embodiment.
[fig.7]Fig. 7 is a sequence diagram showing an operation example of the commu
nication system relating to the fourth exemplary embodiment.
[fig.8]Fig. 8 is a block diagram showing a configuration example of a communication
system having a communication terminal relating to a fifth exemplary embodiment.
[fig.9]Fig. 9 is a sequence diagram showing an operation example of the commu
nication terminal relating to the fifth exemplary embodiment
[fig. 10] Fig. 10 is a sequence diagram showing an operation example of the commu
nication terminal relating to the fifth exemplary embodiment.
[fig. 1l]Fig. 11 is a drawing showing information held by a flow table provided in an
OpenFlow switch as an example.
Description of Embodiments
[0018] First, a summary of the present disclosure will be given. Note that the drawing
reference signs used in the summary are given solely to facilitate understanding and
not to limit the present disclosure to the illustrated aspects.
[0019] In Figs. 1 and 2, a communication terminal (101) communicates with a network
(communication subsystem a-2) that includes a control apparatus (packet forwarding
control apparatus 5a) that generates a processing rule defining a packet processing
method, and comprises request means (a request unit 10) that requests an address of
the control apparatus (5a) when requesting for establishing a connection with the com
munication subsystem a-2, communication means (a communication unit 11) that e s
tablishes a communication channel to the control apparatus (5a) based on the address
acquired by the address request, and processing means (a processing unit 12) that
processes a packet based on a processing rule transmitted from the control apparatus
(5a) via the communication channel.
[0020] The request means (10) may acquire the address of the control apparatus (5a) from a
response to the request for establishing a connection with the communication
subsystem a-2.
[0021] The communication means (11) may release the address according to a prede
termined condition. The communication means (11) may release the address when the
communication terminal (101) moves from a first network (communication network A)
to a second network (communication network B). Further, the communication means
(11) may release the address when the communication terminal (101) disconnects a
connection with the network (A). Moreover, the communication means (11) may
determine whether or not to release the address according to a cause for disconnecting
a connection with the network (A).
[0022] The processing means (12) may release at least one of the processing rules set by the
control apparatus (5a) according to a predetermined condition. The processing means
(12) may release the processing rule set by the control apparatus (5a) belonging to the
first network (A) when the communication terminal (101) moves from the first
network (A) to the second network (B). Further, the processing means (12) may release
the processing rule set by the control apparatus (5a) belonging to the first network (A)
when the communication terminal (101) disconnects a connection with the network
(A). Moreover, the processing means (12) may determine whether or not to release the
processing rule according to a cause for disconnecting a connection with the network
(A).
[0023] The request means (10) may notify whether or not the communication terminal (101)
hold the address. The request means (10) may insert into the address request in
formation indicating whether or not the communication terminal (101) holds the
address. Further, the request means (10) may restrain from requesting the address when
the communication terminal (101) holds the address.
[0024] According to the communication terminal relating to the present disclosure, it
becomes possible to establish a communication channel between a control apparatus
that centrally controls a network and a communication terminal even when the commu
nication terminal changes the network it accesses.
[0025] (First Exemplary Embodiment)
A communication terminal relating to a first exemplary embodiment will be
described with reference to the drawings. Fig. 1 is a drawing for explaining an example
of an operation of a communication terminal 101 relating to the present exemplary em
bodiment. Further, a system shown in Fig. 1 illustrates an example of the present
disclosure, and the present disclosure is not limited to the system shown in Fig. 1. The
communication terminal 101 communicates with a communication network A or B.
The communication network A includes communication subsystems a-1 and a-2.
Meanwhile, the communication network B includes communication subsystems b-1
and b-2.
[0026] The communication subsystem a-1 comprises a router apparatus 2a and a gateway
apparatus 3a, and the communication subsystem b-1 comprises a router apparatus 2b
and a gateway apparatus 3b. The router apparatuses 2a and 2b forward a packet sent/
received to/from the communication terminal 101. The gateway apparatuses 3a and 3b
construct a logical channel to the communication terminal 101, and relay between the
communication subsystems a-1 and b-1 and the communication terminal 101.
[0027] The communication subsystem a-2 comprises a packet forwarding apparatus 4a, a
packet forwarding control apparatus 5a, and a server apparatus 6a, and the commu
nication subsystem b-2 comprises a packet forwarding apparatus 4b, a packet
forwarding control apparatus 5b, and a server apparatus 6b.
[0028] The packet forwarding control apparatuses 5a and 5b centrally control processing
such as packet forwarding by the communication terminal 101 and a plurality of packet
forwarding apparatuses 4a and 4b. The packet forwarding control apparatuses 5a and
5b control the communication terminal 101 and the packet forwarding apparatus 4a or
4b by, for instance, setting a processing rule defining a processing content for a packet
in the communication terminal 101 and the packet forwarding apparatus 4a or 4b. The
processing rule includes, for instance, a matching rule for identifying a packet corre
sponding to this processing rule, and a processing method to be executed on a packet
matching this matching rule. Further, the method in which the packet forwarding
control apparatuses 5a and 5b control the communication terminal 101 and the packet
forwarding apparatus 4a or 4b is not limited to the method described above.
[0029] For instance, the packet forwarding apparatuses 4a and 4b comprise a table that holds
a processing rule set by the packet forwarding control apparatus 5a or 5b. The packet
forwarding apparatuses 4a and 4b search a processing rule corresponding to each
packet in the table. The packet forwarding apparatuses 4a and 4b search a processing
rule that includes a matching rule matching information included in a packet (for
instance, packet header information) in the table. When finding a processing rule that
includes an identification condition matching the information included in a packet, the
packet forwarding apparatuses 4a and 4b process the packet based on the packet
processing method defined in this processing rule. Further, the method in which the
packet forwarding apparatuses 4a and 4b process a packet is not limited to the method
described above.
[0030] The server apparatuses 6a and 6b provide a predetermined service such as a Web
service. The service provided by the server apparatuses 6a and 6b is not limited to a
Web service, and the server apparatuses 6a and 6b are able to provide various services.
For instance, the packet forwarding control apparatuses 5a and 5b control the commu
nication terminal 101 and the packet forwarding apparatus 4a or 4b, and set a commu
nication path between the server apparatus 6a or 6b and the communication terminal
101.
[0031] Fig. 2 is a block diagram showing an example of the configuration of the commu
nication terminal 101 in the present exemplary embodiment. The communication
terminal 101 comprises, for instance, the request unit 10, the communication unit 11,
the processing unit 12, and a processing rule storage unit 13. The communication
terminal 101 is a terminal comprising communication functions such as that of a
mobile terminal, personal computer, and mobile router. Details will be described later,
but the communication terminal 101 is controlled by the packet forwarding control
apparatus 5a or 5b as the packet forwarding apparatuses 4a and 4b. Therefore, the com
munication terminal 101 comprises functions of communicating with the packet
forwarding control apparatus 5a and 5b and receiving a processing rule. In order for
the communication terminal 101 to communicate with the packet forwarding control
apparatus 5a or 5b, the communication terminal 101 must recognize the address of the
packet forwarding control apparatus 5a or 5b. Below, an operation example in which
the communication terminal 101 acquires the address of the packet forwarding control
apparatus 5a will be described.
[0032] The request unit 10 requests the communication network A to establish a connection
(i.e., logical channel) for communicating with the communication subsystem a-2. For
instance, a logical channel is a tunneled connection such as a bearer or VPN (Virtual
Private Network) tunnel established in a wireless section between a wireless control
station and a mobile station. The request unit 10 requests for an address (such as an IP
address) of the packet forwarding control apparatus 5a from the communication
network A, in addition to the request for establishing the logical channel.
[0033] For instance, when the address of the packet forwarding control apparatus 5a is
notified from the communication network A, the request unit 10 sets the notified
address in the communication unit 11. For instance, the gateway apparatus 3a notifies
the address of the packet forwarding control apparatus 5a in response to the request of
the request unit 10. For instance, the gateway apparatus 3a holds the address of the
packet forwarding control apparatus 5a in advance and notifies the address in response
to the request of the request unit 10. Further, the gateway apparatus 3a notifies the
address of the packet forwarding control apparatus 5a in conjunction with a response to
the request for establishing the logical channel.
[0034] The communication unit 11 establishes a control communication channel to the
packet forwarding control apparatus 5a based on the acquired address. The commu
nication unit 11 establishes a secure connection as the control communication channel
using a predetermined method. The communication unit 11 receives a processing rule
from the packet forwarding control apparatus 5a via the control communication
channel. Further, the communication unit 11 requests the packet forwarding control
apparatus 5a to set the processing rule via the control communication channel. The
communication unit 11 stores the processing rule received from the packet forwarding
control apparatus 5a in the processing rule storage unit 13.
[0035] When sending/receiving a packet to/from the communication network A or B, the
processing unit 12 searches a processing rule corresponding to this packet in the
processing rule storage unit 13. When the processing rule corresponding to the packet
is stored in the processing rule storage unit 13, the processing unit 12 executes
processing that corresponds to the processing rule corresponding to the packet.
Meanwhile, when the processing rule storage unit 13 does not store any processing rule
corresponding to the packet, for instance, the processing unit 12 requests the packet
forwarding control apparatus 5a to set a processing rule via the control communication
channel. Further, the processing unit 12 is a module obtained by virtualizing OpenFlow
switch, which is a related technology listed above, using software.
[0036] Fig. 3 shows an example of a processing rule stored in the processing rule storage
unit 13. For instance, a processing rule includes a matching rule for checking whether
or not a packet matches the processing rule and a packet processing method. Fig. 3
indicates "Flow #A" and "Flow #B" as examples of matching rules. "Flow" denotes a
series of packet groups specified by predetermined information such as the destination
address and the source address of a packet and a combination of these pieces of in
formation. For instance, "Flow #A" means that a packet having the destination address
"A" and the source address "a" matches this matching rule. A packet that matches a
matching rule is processed by a processing method corresponding to this matching
rule.
[0037] When releasing the connection with the communication network, the communication
unit 11 may release the address of the packet forwarding control apparatus 5.
[0038] Next, with reference to Figs. 4 and 5, an operation of the communication terminal
101 relating to the present exemplary embodiment will be described. Note that op
erations shown in Figs. 4 and 5 are examples, and the operation of the communication
terminal 101 relating to the present exemplary embodiment is not limited to what is
shown in Figs. 4 and 5.
[0039] Figs. 4 and 5 show operation examples in which the communication terminal 101
roams from the communication network A to the communication network B after com
municating with the communication network A, as shown in Fig. 1.
[0040] With reference to Fig. 4, when communicating with the communication network A,
the communication terminal 101 requests for establishing a logical channel. For
instance, the communication terminal 101 requests the gateway apparatus 3a of the
communication network A to establish a logical channel.
[0041] In addition to the request for establishing a logical channel, the communication
terminal 101 requests for the address of the packet forwarding control apparatus 5a that
belongs to the communication network A. The gateway apparatus 3a notifies the com
munication terminal 101 of the address of the packet forwarding control apparatus 5a
through a response to establishing a logical channel as a response to the address
request.
[0042] The communication terminal 101 constructs (establishes) a control communication
channel to the packet forwarding control apparatus 5a based on the notified address.
[0043] For instance, the communication terminal 101 performs data communication with the
server apparatus 6a that belongs to the communication network A based on a
processing rule received from the packet forwarding control apparatus 5a via the
control communication network.
[0044] The communication terminal 101 releases the logical channel established between
the communication network A and itself at a predetermined timing such as when the
data communication has ended. In the example shown in Fig. 4, the communication
terminal 101 releases the logical channel when roaming from the communication
network A to the communication network B. Further, the communication terminal 101
may release the address of the packet forwarding control apparatus 5a, in addition to
the logical channel.
[0045] Fig. 5 shows an operation example after the communication terminal 101 has roamed
to the communication network B. The communication terminal 101 executes the same
operation as the operation example described using Fig. 4 with the gateway apparatus
3b, the packet forwarding control apparatus 5b, and the server apparatus 6b that belong
to the communication network B.
[0046] According to the present disclosure, even when changing the network to access, a
communication terminal is able to establish a communication channel to a controller
that centrally controls the network without resetting the address of the controller in the
communication terminal.
[0047] Further, in the present exemplary embodiment, the packet forwarding apparatuses 4a
and 4b and the packet forwarding control apparatus 5a and 5b may be implemented
based on the OpenFlow technology. However, the packet forwarding apparatuses 4a
and 4b and the packet forwarding control apparatus 5a and 5b may be implemented
using a technology other than OpenFlow.
[0048] (Second Exemplary Embodiment)
Next, a communication terminal relating to a second exemplary embodiment will be
described. The communication terminal of the present exemplary embodiment is a
variation of the communication terminal 101 relating to the first exemplary em
bodiment.
[0049] The communication unit 11 may release the address of the packet forwarding control
apparatus 5a or 5b according to a predetermined condition. In the present exemplary
embodiment, several examples in which the communication unit 11 releases the
address will be illustrated. Note that these are merely examples, and the method in
which the communication unit 11 releases the address is not limited to the examples
below. Further, the communication unit 11 does not have to release the address.
[0050] The communication unit 11 releases the address of the packet forwarding control
apparatus 5a when the communication terminal 101 roams from the communication
network A to the communication network B. When the communication terminal 101
roams to the communication network B, the packet forwarding control apparatus 5a
that belongs to the communication network A may no longer be an appropriate packet
forwarding control apparatus for the communication terminal 101. When the commu
nication terminal 101 roams to the communication network B, the communication
terminal 101 may be controlled more appropriately for the communication network B
if it communicates with the packet forwarding control apparatus 5b that belongs to the
communication network B. Therefore, the communication unit 1 1 releases the address
of the packet forwarding control apparatus that it is holding when communicating with
another communication network due to roaming. Releasing the address can prevent a
processing rule from being set in the communication unit 11 by the packet forwarding
control apparatus 5a that belongs to the communication network A, the roaming
source, and prevent the communication terminal 101 from executing a processing rule
inappropriate for the communication network B, the roaming destination.
[0051] An example in which the communication unit 11 releases the address of the packet
forwarding control apparatus 5a that belongs to the communication network A when
roaming from the communication network A to B has been described, however, it may
be configured that the processing unit 12 releases a processing rule set by the packet
forwarding control apparatus 5a of the communication network A in the processing
rule storage unit 13.
[0052] The communication unit 11 may release the address that it holds when the
connection to the communication network to which the communication unit 11 is
connected is disconnected. When the connection to the communication network is dis
connected, there is a possibility that the communication terminal 101 connects to
another communication network due to degradation of communication quality.
Therefore, when the connection to the communication network A is disconnected,
having the communication unit 11 release the address of the packet forwarding control
apparatus 5a can prevent a processing rule from being set in the communication unit 11
by the packet forwarding control apparatus 5a that belongs to the communication
network A, the roaming source, and prevent the communication terminal 101 from
executing a processing rule inappropriate for the communication network B, the
roaming destination.
[0053] An example in which the communication unit 11 releases the address of the packet
forwarding control apparatus 5a when the connection to the communication network A
is disconnected has been described, however, it may be configured that the processing
unit 12 releases a processing rule set by the packet forwarding control apparatus 5a that
belongs to the communication network A to which the communication unit 11 is
connected before the disconnection.
[0054] The communication unit 11 may determine whether or not to release the address of
the packet forwarding control apparatus 5a based on a main cause of the disconnection
when the connection to the communication network A is disconnected. For instance,
after the disconnection, the communication terminal 101 retries to connect to the same
communication network A. When it is possible to receive a radio wave from the same
communication network A at a level where reconnection is possible, the commu
nication terminal 101 recognizes that the connection has been disconnected from the
fact that it is temporarily in a coverage hole of the wireless network. In this case, since
it is possible for the communication terminal 101 to reconnect to the same commu
nication network A, the address of the packet forwarding control apparatus 5a does not
have to be released.
[0055] When the communication terminal 101 is unable to receive a radio wave from the
same communication network A at a level where reconnection is possible for a prede
termined period of time because the distance between a base station of the wireless
network and the terminal has increased (such as when it goes into the underground),
the communication terminal 101 can assume that this may continue for a long period of
time. In this case, the communication terminal 101 may release the address of the
packet forwarding control apparatus 5a.
[0056] An example in which the communication unit 11 determines whether or not to
release the address of the packet forwarding control apparatus 5a based on a main
cause of the disconnection has been described, however, the processing unit 12 may
determine whether or not to release a processing rule set by the packet forwarding
control apparatus 5a that belongs to the communication network A to which the com
munication terminal 101 was connected before the disconnection.
[0057] (Third Exemplary Embodiment)
A communication terminal relating to a third exemplary embodiment will be
described. The communication terminal of the present exemplary embodiment is a
variation of the communication terminal relating to the first exemplary embodiment.
[0058] In the first exemplary embodiment described above, the request unit 10 requests the
address of the packet forwarding control apparatus 5a. In the present exemplary em
bodiment, the request unit 10 transmits information indicating whether or not the com
munication terminal 101 holds the address of the packet forwarding control apparatus
5a, in addition to the request for establishing a logical channel to the communication
network A. Further, the information indicating whether or not the communication
terminal 101 holds the address of the packet forwarding control apparatus 5a has, for
instance, a flag indicating whether or not the terminal holds the address.
[0059] In such a configuration, when responding to the request for establishing a logical
channel, the gateway apparatus 3a can notify the address of the packet forwarding
control apparatus 5a only when the communication terminal 101 does not hold the
address of the packet forwarding control apparatus 5a. In this case, the information
amount transmitted in the response to the request for establishing a logical channel can
be reduced.
[0060] Further, the request unit 10 may refrain from requesting the address of the packet
forwarding control apparatus 5a when the communication terminal 101 holds the
address of the packet forwarding control apparatus 5a.
[0061] (Fourth Exemplary Embodiment)
A communication terminal relating to a fourth exemplary embodiment will be
described with reference to the drawings.
[0062] In the present exemplary embodiment, the present disclosure is implemented in a 3G
(3rd Generation) network.
[0063] Fig. 6 shows a system configuration example of the present exemplary embodiment.
Note that the configuration shown in Fig. 6 is an example, and the present disclosure is
not limited to the configuration shown in Fig. 6.
[0064] A communication network, which a communication terminal 104 communicates
with, includes a mobile network and a data center. The mobile network comprises a
UTRAN 20, an SGSN 30, and a GGSN 40. The data center includes a packet
forwarding apparatus 4, a packet forwarding control apparatus 5, and a server
apparatus 6.
[0065] The UTRAN (UMTS Terrestrial Radio Access Network) 20 is a wireless network
comprising a base station and an RNC (Radio Network Controller). The UTRAN 20 is
a wireless network that connects between the communication terminal 104 and a core
network. The core network connects the communication terminal 104 conforming to a
3G communication standard such as WCDMA (Wideband Code Division Multiple
Access) to an external network such as the Internet.
[0066] The SGSN (Serving GPRS Support Node) 30 is a part of the aforementioned core
network. The SGSN 30 executes routing of packet communication of the commu
nication terminal 104, mobility management (attach/detach to/from the wireless com
munication network, location management, etc.) of the communication terminal 104,
management of a logical channel between the communication terminal 104 and the
network, and authentication processing.
[0067] The GGSN (Gateway GPRS Support Node) 40 is a part of the aforementioned core
network. The GGSN 40 relays communication with an external packet communication
network. In the example of Fig. 6, the GGSN 40 relays communication with the data
center.
[0068] Since the packet forwarding apparatus 4, the packet forwarding control apparatus 5,
and the server apparatus 6 are the same as in the first exemplary embodiment described
above, explanation of them will be omitted.
[0069] With reference to Fig. 7, an operation example of the communication terminal 104
relating to the present exemplary embodiment will be described. Note that the
operation shown in Fig. 7 is an example, and the present disclosure is not limited to the
operation in Fig. 7.
[0070] The communication terminal 104 transmits an "Active PDP (Packet Data Protocol)
Context Request" message to the SGSN 30, a wireless network to which the commu
nication terminal 104 belongs, via the UTRAN 20. Note that "PDP Context" is status
information on the path configuration of a logical packet forwarding path from the
communication terminal 104 to the GGSN in a packet data network in 3G commu
nication standards. This message includes the APN (Access Point Name) of the ISP
(Internet Service Provider), to which the communication terminal 104 sends a
connection request and connects. The APN is used as information for identifying the
ISP. Further, in the present exemplary embodiment, the communication terminal 104
requests a connection to the data center in Fig. 6, and this data center corresponds to
the ISP. In the present exemplary embodiment, the communication terminal 104
includes the request for acquiring the address of the packet forwarding control
apparatus 5 in the Active PDP Context Request message and transmits the message.
Upon receiving the Active PDP Context Request, the SGSN 30 determines the GGSN
40 to be connected based on the APN included in the message. The SGSN 30 transmits
a Create PDP Context Request message to the GGSN 40.
[0071] Upon receiving the Create PDP Context Request, the GGSN 40 executes prede
termined processing (for instance, generating a PDP Context) for connecting the com
munication terminal 104 and the ISP. The GGSN 40 returns the generated PDP
Context to the SGSN 30 as a Create PDP Context Response message. Further, in the
present exemplary embodiment, the GGSN 40 includes the address of the packet
forwarding control apparatus 5 in the Create PDP Context Response and returns it to
the SGSN 30. For instance, the GGSN 40 holds the address of the packet forwarding
control apparatus 5 by means of a procedure such as acquiring the address by commu
nicating with the packet forwarding control apparatus 5 in advance.
[0072] The SGSN 30 receives the Create PDP Context Response and sets up a logical
channel for executing packet forwarding between the communication terminal 104 and
the communication network (Radio Access Bearer Setup). The SGSN 30 returns an
Active PDP Context Accept message to the communication terminal 104. The SGSN
30 includes the address of the packet forwarding control apparatus 5 in this message
and transmits the message to the communication terminal 104.
[0073] The communication terminal 104 executes communication with the data center in the
operation described above. The communication terminal 104 sets up a control commu
nication channel to the packet forwarding control apparatus 5 based on the acquired
address of the packet forwarding control apparatus 5. The packet forwarding control
apparatus 5 sets a predetermined processing rule in the communication terminal 104
through this control communication channel.
[0074] (Fifth Exemplary Embodiment)
A communication terminal relating to a fifth exemplary embodiment of the present
disclosure will be described with reference to the drawings.
[0075] In the present exemplary embodiment, the present disclosure is implemented in an
LTE (Long Term Evolution) network.
[0076] Fig. 8 shows a system configuration example of the present exemplary embodiment.
Note that the configuration shown in Fig. 8 is an example, and the present disclosure is
not limited to the configuration shown in Fig. 8.
[0077] A communication network, which a communication terminal 105 communicates
with, includes a mobile network and a data center. The mobile network comprises an
eNodeB 200, a Serving GW (Gateway) 300, an MME (Mobility Management Entity)
400, and a PDN (Packet Data Network) GW 500. The data center comprises the packet
forwarding apparatus 4, the packet forwarding control apparatus 5, and the server
apparatus 6.
[0078] The eNodeB 200 functions as an interface between the communication terminal 105
and a wireless network. Further, the eNodeB 200 has functions of radio resource
management and radio resource scheduling.
[0079] The Serving GW 300 routes and forwards a data packet.
[0080] The MME 400 is a control node in the LTE network. The MME 400 executes
mobility management such as location registration of the communication terminal 105,
calling, and handover between the eNodeBs 200.
[0081] The PDN GW 500 functions as a gateway to an external network. For instance, in the
LTE network in Fig. 8, the PDN GW 500 functions as a gateway between the mobile
network and the data center.
[0082] With reference to Fig. 9, an operation example of the communication terminal 105
relating to the present exemplary embodiment will be described. Note that the
operation shown in Fig. 9 is an example, and the operation of the present disclosure is
not limited to the operation in Fig. 9.
[0083] The communication terminal 105 transmits an "Attach Request" to the MME 400.
The communication terminal 105 requests a connection to the mobile network
managed by the MME 400 with the "Attach Request." The communication terminal
105 includes the request for the address of the packet forwarding control apparatus 5 in
the "Attach Request."
[0084] Upon receiving the "Attach Request," the MME 400 transmits a Create Session
Request to the Serving GW 300. The MME 400 includes the request for the address of
the packet forwarding control apparatus 5 in the Create Session Request.
[0085] The Serving GW 300 forwards the received Create Session Request to the PDN GW
500.
[0086] The PDN GW 500 receives the Create Session Request, generates a Bearer Context,
and transmits a Create Session Response to the MME 400 via the Serving GW 300.
The PDN GW 500 includes the address of the packet forwarding control apparatus 5 in
the Create Session Response. For instance, the PDN GW 500 acquires the address of
the packet forwarding control apparatus 5 by means of processing such as commu
nicating with the packet forwarding control apparatus 5 in advance and manages the
address.
[0087] The MME 400 requests the eNodeB 200 to set up wireless communication with the
communication terminal 105 (Initial Context Setup Request) based on the Bearer
Context included in the Create Session Response received from the PDN GW 500. The
MME 400 includes an Attach Accept message in the Initial Context Setup Request.
This Attach Accept message includes the address of the packet forwarding control
apparatus 5.
[0088] The eNodeB 200 requests the communication terminal 105 to configure wireless
communication (RRC Connection Reconfiguration). Further, by including the Attach
Accept message received from the MME 400 in the above request, the eNodeB 200
notifies the communication terminal 105 of the address of the packet forwarding
control apparatus 5.
[0089] The communication terminal 105 notifies that the configuration of the wireless com
munication has been completed based on the request (RRC Connection Recon
figuration Complete). The communication terminal 105 sets the address of the packet
forwarding control apparatus 5 according to the configuration of the wireless commu
nication.
[0090] The eNodeB 200 notifies MME 400 that the configuration of the wireless commu
nication has been completed (Initial Context Setup Response).
[0091] Next, the communication terminal 105 notifies the MME 400 that the connection to
the mobile network has succeeded (Attach Complete).
[0092] By means of the procedure described above, the communication terminal 105 e s
tablishes the logical channel for connecting to the mobile network and acquires the
address of the packet forwarding control apparatus 5.
[0093] Next, with reference to Fig. 10, another operation example of the communication
terminal 105 relating to the present exemplary embodiment will be described. Note
that the operation shown in Fig. 10 is an example, and the operation of the present
disclosure is not limited to the operation in Fig. 10.
[0094] The operation shown in Fig. 10 is an operation after the communication terminal 105
has been connected to the wireless network by means of the operation shown in Fig. 9.
The communication terminal 105 includes the request for the address of the packet
forwarding control apparatus 5 in the "Attach Request" in Fig. 9. However, the com
munication terminal 105 may request for the address of the packet forwarding control
apparatus 5 in the operation shown in Fig. 10, instead of including the address request
in the "Attach Request."
[0095] The communication terminal 105 transmits a "PDN Connectivity Request" message
to the MME 400 via the eNodeB 200. The "PDN Connectivity Request" is a message
that requests another logical channel to be established, in addition to the logical
channel established between the communication terminal 105 and the mobile network
during the operation of Fig. 9.
[0096] The communication terminal 105 includes the request for the address of the packet
forwarding control apparatus 5 in the "PDN Connectivity Request."
[0097] Upon receiving the "PDN Connectivity Request," the MME 400 transmits a Create
Session Request to the Serving GW 300. The MME 400 includes the request for the
address of the packet forwarding control apparatus 5 in the Create Session Request.
[0098] The Serving GW 300 forwards the received Create Session Request to the PDN GW
500.
[0099] The PDN GW 500 receives the Create Session Request, generates a Bearer Context,
and transmits a Create Session Response to the MME 400 via the Serving GW 300.
The PDN GW 500 includes the address of the packet forwarding control apparatus 5 in
the Create Session Response. For instance, the PDN GW 500 acquires the address of
the packet forwarding control apparatus 5 by means of processing such as commu
nicating with the packet forwarding control apparatus 5 in advance and manages the
address.
[0100] The MME 400 requests the eNodeB 200 to set up wireless communication with the
communication terminal 105 (Bearer Setup Request) based on the Bearer Context
included in the Create Session Response received from the PDN GW 500. The MME
400 includes a PDN Connectivity Accept message in the Bearer Setup Request. This
PDN Connectivity Accept message includes the address of the packet forwarding
control apparatus 5.
[0101] The eNodeB 200 requests the communication terminal 105 to configure wireless
communication (RRC Connection Reconfiguration). Further, by including the PDN
Connectivity Accept message received from the MME 400 in the above request, the
eNodeB 200 notifies the communication terminal 105 of the address of the packet
forwarding control apparatus 5.
[0102] The communication terminal 105 notifies that the configuration of the wireless com
munication has been completed based on the request (RRC Connection Recon
figuration Complete). The communication terminal 105 sets the address of the packet
forwarding control apparatus 5 according to the configuration of the wireless commu
nication.
[0103] The eNodeB 200 notifies MME 400 that the configuration of the wireless commu
nication has been completed (Bearer Setup Response).
[0104] Next, the communication terminal 105 notifies the MME 400 that the construction of
the logical channel has succeeded (PDN Connectivity Complete).
[0105] By means of the procedure described above, the communication terminal 105 e s
tablishes the logical channel for connecting to the mobile network and acquires the
address of the packet forwarding control apparatus 5.
[0106] The exemplary embodiments of the present disclosure have been described above,
however, the present disclosure is not limited to the above exemplary embodiments
and further modifications, replacements, and adjustments can be added.
[0107] Further, each disclosure of Patent Literature and Non Patent Literatures listed above
is incorporated herein in its entirety by reference thereto. Modifications and adjustments
of the exemplary embodiment(s) are possible within the scope of the overall
disclosure (including the claims) of the present disclosure and based on the basic
technical concept of the present disclosure. Various combinations and selections of
various disclosed elements (including each element of each claim, each element of
each exemplary embodiment, each element of each drawing, etc.) are possible within
the scope of the claims of the present invention. That is, the present invention of course
includes various variations and modifications that could be made by those skilled in
the art according to the overall disclosure including the claims and the technical
concept.
Reference Signs List
2a, 2b: router apparatus
3a, 3b: gateway apparatus
4, 4a, 4b: packet forwarding apparatus
5, 5a, 5b: packet forwarding control apparatus
6, 6a, 6b: server apparatus
10: request unit
11: communication unit
12: processing unit
13: processing rule storage unit
20: UTRAN
30: SGSN
40: GGSN
101, 104, 105: communication terminal
200: eNodeB
300: Serving GW
400: MME
500: PDN GW
A, B: communication network
a-1, a-2, b-1, b-2: communication subsystem
PCT/JP2012/005524

Claims
A communication terminal, which communicates with a network
including a control apparatus that generates a processing rule defining a
packet processing method, the communication terminal comprising:
request means that requests an address of the control apparatus when
requesting for establishing a connection to the network;
communication means that establishes a communication channel to the
control apparatus based on an address acquired by the address request;
and
processing means that processes a packet based on a processing rule
transmitted by the control apparatus via the communication channel.
The communication terminal according to claim 1, wherein the request
means acquires an address of the control apparatus from a response to a
request for establishing a connection to a network.
The communication terminal according to claim 1 or 2, wherein the
communication means releases the address according to a prede
termined condition.
The communication terminal according to any one of claims 1 to 3,
wherein the communication means releases the address when the com
munication terminal moves from a first network to a second network.
The communication terminal according to any one of claims 1 to 3,
wherein the communication means releases the address when the com
munication terminal disconnects a connection to the network.
The communication terminal according to any one of claims 1 to 3,
wherein the communication means determines whether or not to release
the address according to a cause for disconnecting a connection to the
network.
The communication terminal according to any one of claims 1 to 6,
wherein the processing means releases at least one processing rule set
by the control apparatus according to a predetermined condition.
The communication terminal according to any one of claims 1 to 7,
wherein the processing means releases a processing rule set by a
control apparatus that belongs to a first network when the commu
nication terminal moves from the first network to a second network.
The communication terminal according to any one of claims 1 to 7,
wherein the processing means releases a processing rule set by a
control apparatus that belongs to the network when the communication
PCT/JP2012/005524
terminal disconnects a connection to the network.
The communication terminal according to any one of claims 1 to 7,
wherein the processing means determines whether or not to release the
processing rule according to a cause for disconnecting a connection to
the network.
The communication terminal according to any one of claims 1 to 10,
wherein the request means notifies whether or not the communication
terminal holds the address.
The communication terminal according to any one of claims 1 to 11,
wherein the request means inserts into the address request information
indicating whether or not the communication terminal holds the
address.
The communication terminal according to any one of claims 1 to 12,
wherein the request means refrains from requesting the address when
the communication terminal holds the address.
A communication method, in which a communication terminal is used
that communicates with a network including a control apparatus that
generates a processing rule defining a packet processing method, the
method comprising:
requesting an address of the control apparatus when requesting for e s
tablishing a connection to the network;
establishing a communication channel to the control apparatus based on
an address acquired by the address request; and
processing a packet based on a processing rule transmitted by the
control apparatus via the communication channel.
The communication method according to claim 14, wherein the com
munication terminal acquires an address of the control apparatus from a
response to a request for establishing a connection to a network.
The communication method according to claim 14 or 15, wherein the
communication terminal releases the address according to a prede
termined condition.
The communication method according to any one of claims 14 to 16,
wherein the communication terminal releases the address when the
communication terminal moves from a first network to a second
network.
The communication method according to any one of claims 14 to 16,
wherein the communication terminal releases the address when the
communication terminal disconnects a connection to the network.
PCT/JP2012/005524
The communication method according to any one of claims 14 to 16,
wherein the communication terminal determines whether or not to
release the address according to a cause for disconnecting a connection
to the network.
The communication method according to any one of claims 14 to 19,
wherein the communication terminal releases at least one processing
rule set by the control apparatus according to a predetermined
condition.
The communication method according to any one of claims 14 to 20,
wherein the communication terminal releases a processing rule set by a
control apparatus that belongs to a first network when the commu
nication terminal moves from the first network to a second network.
The communication method according to any one of claims 14 to 20,
wherein the communication terminal releases a processing rule set by a
control apparatus that belongs to the network when the communication
terminal disconnects a connection to the network.
The communication method according to any one of claims 14 to 20,
wherein the communication terminal determines whether or not to
release the processing rule according to a cause for disconnecting a
connection to the network.
The communication method according to any one of claims 14 to 23,
wherein the communication terminal notifies whether or not the com
munication terminal holds the address.
The communication method according to any one of claims 14 to 24,
wherein the communication terminal inserts into the address request in
formation indicating whether or not the communication terminal holds
the address.
The communication method according to any one of claims 14 to 25,
wherein the communication terminal refrains from requesting the
address when the communication terminal holds the address.
A communication system comprising:
a network including a control apparatus that generates a processing rule
defining a packet processing method; and
a communication terminal that communicates with the network;
the communication terminal further comprising:
request means that requests an address of the control apparatus when
requesting for establishing a connection to the network;
communication means that establishes a communication channel to the
WO 2013/031233 PCT/JP2012/005524
control apparatus based on an address acquired by the address request;
and
processing means that processes a packet based on a processing rule
transmitted by the control apparatus via the communication channel.
[Claim 28] A program causing a computer built into a communication terminal that
communicates with a network including a control apparatus that
generates a processing rule defining a packet processing method to
execute:
requesting an address of the control apparatus when requesting for e s
tablishing a connection to the network;
establishing a communication channel to the control apparatus based on
an address acquired by the address request; and
processing a packet based on a processing rule transmitted by the
control apparatus via the communication channel.