1. A communication apparatus comprising: a processing rule storage unit capable of storing a first processing rule for unknown packets set in advance, and a second processing rule set by a control apparatus; 5 a packet processor that processes received packets based on processing rules stored in said processing rule storage unit; and a state notification unit that transmits a predetermined control message to said control apparatus when a packet is processed using said first processing rule; wherein 10 said communication apparatus continues packet processing using said first processing rule until said second processing rule is set by said control apparatus.

2. The communication apparatus according to claim 1, wherein said predetermined message is a control message that requests setting of a second processing rule for packet(s) processed using said first p r o c e s s i n g rule, with respect to said control apparatus.

3. The communication apparatus according to claim 1 or 2, wherein said state notification unit transmits, in a case of receiving a packet that matches neither said first nor said second processing rule, a second control message requesting setting of said second processing rule and 5 an instruction to forward said packet, with respect to said control apparatus.

4. The communication apparatus according to any one of claims 1 to 3, wherein said state notification unit inhibits, after transmission of said predetermined message, transmission of said predetermined control message to said control apparatus, even if a packet is processed using 5 said first processing rule, until a predetermined condition is established.

5. The communication apparatus according to claim 4, wherein said predetermined condition is any of: elapse of a predetermined time, receipt of more than a predetermined number of packets, and receipt of a data amount greater than a predetermined amount.

6. The communication apparatus according to any one of claims 1 to 5, wherein said first processing rule is a processing rule for performing 20 a broadcast or a multicast, by predetermined path(s).

7. A control apparatus, connected to a communication apparatus that i n c l u d e s : a processing rule storage unit capable of storing a first processing rule for unknown packets set in advance, and a second 5 processing rule set by a control apparatus, a packet processor that processes received packets based on processing rules stored in said processing rule storage unit, and a state notification unit that transmits a predetermined control message to said control apparatus when a packet is processed using said 10 first processing rule; wherein said control apparatus creates, on receiving said predetermined control message, said second processing rule to be set in said communication apparatus and sets said second processing rule in said communication apparatus, and also discards packets included in said 1 5 control message.

8. A communication system comprising: a communication apparatus including a processing rule storage unit capable of storing a first processing rule for unknown packets set in advance, and a second 5 processing rule set by a control apparatus, a packet processor that processes received packets based on processing rules stored in said processing rule storage unit, and a state notification unit that transmits a predetermined control message to said control apparatus, when a packet is processed using 10 said first processing rule, wherein said communication apparatus continues packet processing using said first processing rule until said second processing rule is set by said control apparatus; and a control apparatus, connected to said communication apparatus, 15 that creates, on receiving said predetermined control message, said second processing rule to be set in said communication apparatus and sets said rule in said communication apparatus, and also discards packets included in said control message. 21

9. A communication method wherein a communication apparatus that includes a processing rule storage unit capable of storing a first processing rule for unknown packets set in advance, and a second processing rule set by a control apparatus, and a packet processor that 5 processes received packets based on processing rules stored in said processing rule storage unit, performs: a step of t r a n s m i t t i n g a predetermined control message to said control apparatus when a packet is processed using said first processing rule, and a step of continuing packet processing using said first processing rule until said second processing rule is set by said control apparatus.

10. A control method wherein a control apparatus, connected to a communication apparatus that includes a processing rule storage unit capable of storing a first processing rule for unknown packets set in advance and a second processing rule set by a control apparatus, a packet processor that processes received packets based on processing rules stored in said processing rule storage unit, and a state notification unit that transmits a predetermined control message to said control apparatus when a packet is processed using said first processing rule, performs: a step of creating, on receiving said predetermined control message from said communication apparatus, said second processing rule to be set in said communication apparatus, and setting said second processing rule in said communication apparatus, and a step of discarding packets included in said control message.

DESCRIPTION
COMMUNICATION APPARATUS, CONTROL APPARATUS,
COMMUNICATION SYSTEM, COMMUNICATION METHOD, METHOD
5 FOR CONTROLLING COMMUNICATION APPARATUS, AND
PROGRAM
TECHNICAL FIELD
[0001]
10 [REFERENCE TO RELATED APPLICATION]
The present application claims priority from Japanese Patent
Application No. 2012-074655 (filed on March 28, 2012), the content of
which is hereby incorporated in its entirety by reference into this
d i s c l o s u r e . The present invention relates to a communication
15 apparatus, a control apparatus, a communication system, a
communication method, a method for controlling the communication
apparatus, and a program, and in p a r t i c u l a r relates to a communication
apparatus, a control apparatus, a communication system, a method for
c o n t r o l l i n g the communication apparatus, and a program, that perform
20 packet processing in accordance with control information set by the
control apparatus.
BACKGROUND ART
[0002]
With the expansion of network bandwidth, services are required
25 that handle large amounts of data such as image d i s t r i b u t i o n and the like.
As a component technology thereof, OpenFlow in Non Patent Literature
1 and 2 may be cited. In OpenFlow, switches capable of high-speed
forwarding are arranged on a user plane, and by optimally setting path
information by an OpenFlow controller, it is possible to adequately
30 respond to high speed forwarding needs.
CITATION LIST
NON-PATENT LITERATURE
[0003]
[NPL 1]
2
Nick McKeown and 7 others, "OpenFlow: Enabling Innovation in
Campus Networks", [online], [search conducted February 14, 2012],
Internet
5 [NPL 2]
"OpenFlow 1.2", [online], [search conducted March 27, 2012], Internet

10 SUMMARY OF THE INVENTION
TECHNICAL PROBLEM
[0004]
The following analysis is given by the present invention. In a
c e n t r a l l y controlled network as represented by OpenFlow in Non Patent
15 Literature 1 and 2, there is a problem in that, until setting of a
processing rule (equivalent to a flow entry in OpenFlow) by a control
apparatus is completed, it is necessary to perform forwarding (Packet-in,
Packet-out messaging in OpenFlow protocol) via a control plane. In
this way, in a case of a data burst or a large amount of data being
20 inputted, there are problems of load increase in an entire system
including a control apparatus and communication apparatus on an input
side, and of packet loss occurrence.
[0005]
As a result of forwarding via a control plane, before and after
25 setting control information by the control apparatus, there is also a
problem of order being reversed with regard to packets for which the
control apparatus has specified forwarding via the control plane, and
packets for which sequential forwarding is started by a newly set
processing rule. For example, in FIG. 9, a forwarding instruction
30 (Packet-out; S207) is received via the control plane from a controller,
but before that, a Unicast (S206) of a following packet is performed
first by a unicast flow entry set in steps S204, S205 (Flow-mod).
[0006]
It is an object of the present invention to provide a
3
communication apparatus, a control apparatus, a communication system,
a communication method, a method for controlling the communication
apparatus, and a program, that contribute to reducing load when a
r e l a t i v e l y large amount of data is inputted, in the abovementioned
5 centrally controlled network, and to inhibiting reversal of order of
arrival of the packets described above.
SOLUTION TO PROBLEM
[0007]
According to a first aspect, there is provided a communication
10 apparatus that includes: a processing rule storage unit capable of
storing a first processing rule for unknown packets set in advance, and a
second processing rule set by a control apparatus; a packet processor
that processes received packets based on processing rules stored in the
processing rule storage unit; and a state n o t i f i c a t i o n unit that transmits
15 a predetermined message to the control apparatus when a packet is
processed using the first processing rule; wherein the communication
apparatus continues packet processing using the first processing rule
until the second processing rule is set by the control apparatus.
[0008]
20 According to a second aspect, there is provided a control
apparatus connected to the abovementioned communication apparatus,
wherein the control apparatus creates, on receiving the predetermined
control message, the second processing rule to be set in the
communication apparatus and sets the second processing rule in the
25 communication apparatus, and also discards packets included in the
control message.
[0009]
According to a third aspect, there is provided a communication
system including the abovementioned communication apparatus and the
30 control apparatus.
[0010]
According to a fourth aspect, there is provided a communication
method wherein a communication apparatus including a processing rule
storage unit capable of storing a first processing rule for unknown
4
packets set in advance, and a second processing rule set by a control
apparatus, and a packet processor that processes received packets based
on processing rules stored in the processing rule storage unit, performs:
a step of t r a n s m i t t i n g a predetermined control message to the control
5 apparatus when a packet is processed using the first processing rule,
and a step of continuing packet processing using the first processing
rule until the second processing rule is set by the control apparatus.
The present method is linked to a specific apparatus known as a
communication apparatus that processes packets using processing rules
10 from the control apparatus.
[0011]
According to a fifth aspect, there is provided a control method
wherein a control apparatus connected to a communication apparatus
that includes a processing rule storage unit capable of storing a first
15 processing rule for unknown packets set in advance and a second
processing rule set by the control apparatus, a packet processor that
processes received packets based on processing rules stored in the
processing rule storage unit, and a state n o t i f i c a t i o n unit that transmits
a predetermined control message to the control apparatus when a packet
20 is processed using the first processing rule, performs: a step of creating,
on receiving the predetermined control message from the
communication apparatus, the second processing rule to be set in the
communication apparatus, and setting the second processing rule in the
communication apparatus, and a step of discarding packets included in
25 the control message. The present method is linked to a specific
apparatus known as control apparatus that sets processing rules in
response to a request from the communication apparatus.
[0012]
According to a sixth aspect, there is provided a computer program
30 that is executed in each of the communication apparatus and the control
apparatus as described above. It is to be noted that the program may
be recorded on a computer readable ( n o n - t r a n s i t o r y ) recording medium.
That is, the present invention may be embodied as a computer program
product.
5
ADVANTAGEOUS EFFECTS OF INVENTION
[0013]
According to the present invention, in a centrally controlled
network it is possible to contribute to reducing load in respective
5 apparatuses when a large amount of data is inputted, and to inhibiting
reversal of the order of packet transmission.
BRIEF DESCRIPTION OF DRAWINGS
[0014]
[Fig. 1]
10 FIG. 1 is a diagram showing a configuration of an exemplary
embodiment of the present invention.
[Fig. 2]
FIG. 2 is a diagram for describing operations of the exemplary
embodiment of the invention.
15 [Fig. 3]
FIG. 3 is a diagram showing a configuration of a communication system
according to a first exemplary embodiment of the present invention.
[Fig. 4]
FIG. 4 is a diagram showing a configuration of a switch of the first
20 exemplary embodiment of the invention.
[Fig. 5]
FIG. 5 is an example of a flow table held in a communication apparatus
of the first exemplary embodiment of the invention.
[Fig. 6]
25 FIG. 6 is a sequence diagram representing operations of the first
exemplary embodiment of the invention.
[Fig. 7]
FIG. 7 is continuation diagram of FIG. 6.
[Fig. 8]
30 FIG. 8 is a sequence diagram representing operations of a second
exemplary embodiment of the invention.
[Fig. 9]
FIG. 9 is a sequence diagram representing operations among switch
c o n t r o l l e r s of Non Patent Literature 1 and 2 showing comparative
6
examples.
DESCRIPTION OF EMBODIMENTS
[0015]
F i r s t , a description is given of an outline of an exemplary
5 embodiment of the present invention, making reference to the drawings.
It is to be noted that reference symbols in the drawings attached to this
outline are added for convenience to respective elements as examples in
order to aid understanding, and are not intended to limit the invention
to modes shown in the drawings.
10 [0016]
In the exemplary embodiment, as shown in FIG. 1, the present
invention may be realized by a configuration including at least one
communication apparatus 10A and a control apparatus 20A that controls
the communication apparatus 10A. More specifically, the
15 communication apparatus 10A is provided with: a processing rule
storage unit 11A capable of storing a first processing rule for unknown
packets set in advance, and a second processing rule set by a control
apparatus; a packet processor 12A that processes received packets based
on processing rules stored in the processing rule storage unit; and a
20 state notification unit 13A that transmits a predetermined message to
the control apparatus 20A when a packet is processed using the first
processing rule. The communication apparatus 10A continues packet
processing using the first processing rule until the second processing
rule is set by the control apparatus 20A.
25 [0017]
Meanwhile, on receiving the predetermined control message from
the communication apparatus 10A, the control apparatus 20A creates the
second processing rule to be set in the communication apparatus 10A
and sets the second processing rule in the communication apparatus 10A.
30 It is to be noted that the control apparatus 20A discards packets
included in the control message without a packet transmission
i n s t r u c t i o n being performed with regard to the communication apparatus
10A as performed in Non Patent Literature 1 and 2 (namely, a packet
forwarding operation via a control plane is not performed).
7
[0018]
By the above configuration, even if a large amount of data is
inputted, since processing is performed by the first processing rule, the
control apparatus 20A is not overloaded. As shown in FIG. 2, after the
5 second processing rule has been set by the control apparatus 20A, as a
known packet, switching to processing by the second processing rule is
performed, so that packet transmission order is not reversed.
[0019]
[First Exemplary Embodiment]
10 Next, a detailed description is given concerning a first exemplary
embodiment of the present invention, making reference to the drawings.
FIG. 3 is a diagram showing a configuration of a communication system
according to the first exemplary embodiment of the present invention.
FIG. 3 shows the communication system that including switches 10-1 to
15 10-3 connected to one another, and a controller 20 that controls the
switches 10-1 to 10-3. A server 30 and a client 40 in FIG. 3 can
communicate via the switches 10-1 and 10-3, respectively. It is to be
noted that solid lines in FIG. 3 indicate network connection
r e l a t i o n s h i p s , and broken lines represent channels for control between
20 the controller 20 and the switches.
[0020]
FIG. 4 is a diagram showing a configuration of the switch 10-1 of
the first exemplary embodiment of the present invention. FIG. 4 shows
the controller 20 that controls the switch 10-1 by setting flow entries in
25 the switch 10-1, and the switch 10-1 that r e t r i e v e s a flow entry having a
match field that matches a received packet, from among flow entries set
by the controller 20, to perform packet processing.
[0021]
The switch 10-1 is provided with a flow entry storage unit 11
30 (equivalent to a processing rule storage unit 11A described above) that
stores flow entries, a packet processor 12 (equivalent to a packet
processor 12A described above) that processes received packets in
accordance with a flow entry stored in the flow entry storage unit 11,
and a controller communication unit 13 (equivalent to a state
8
n o t i f i c a t i o n unit 13A described above) that, in a case where a received
packet in the packet processing unit 12 matches a flow entry for an
Unknown Unicast and forwarding is performed, transmits a control
message indicating this to the controller 20.
5 [0022]
FIG. 5 is a diagram showing an example of a flow entry storage
table (flow table) stored in the flow entry storage unit 11. A Priority
field in the diagram indicates the priority of each flow entry. The
example of FIG. 5 shows an example in which 3 flow e n t r i e s , Priority =
10 65535, Priority = 60000, and Priority = "a" (note that "a" < 60000) are
r e g i s t e r e d . Among these, the flow entry with Priority = 65535 is the
highest priority flow entry.
[0023]
A retrieval condition field in FIG. 5 stores information of match
15 fields to match received packets. In the flow entry in the diagram
where "Exact" is specified, matching is performed according to Exact
Matching with a received packet header or the like. For a flow entry
where dl_dest = X.X.X.X is specified, a data link layer address of a
received packet, that is, where a destination MAC address is X.X.X.X,
20 is matched. In a case of a flow entry where In port = 0/bb is specified,
there is a match with a packet inputted from port 0/bb.
[0024]
An action field in FIG. 5 shows processing content to be applied
to a received packet where there is a match with a condition shown in
25 the retrieval condition field. For example, for a packet matching a
flow entry with Priority = 65535, processing to forward from port 0/cc
is performed (that is, forwarding to switch 10-2). For example, for a
packet matching a flow entry with Priority = 60000, processing to
forward from port 0/dd is performed (that is, forwarding to switch 10-3).
30 For example, for a packet matching a flow entry with Priority = "a",
flooding processing to forward from port 0/cc and port 0/dd (see
FLOOD in "4.5 Reserved ports" of Non Patent Literature 2) and
t r a n s m i s s i o n of a Packet-in message (forwarding done) giving
n o t i f i c a t i o n of new packet reception to the controller 20 (that is,
9
forwarding to switches 10-2, 10-3) are performed. The Packet-in
message (forwarding done) differs from a Packet-in message described
in Non Patent Literature 1 and 2, and is a control message to which is
attached an identifier whereby at least the controller 20 gives
5 notification that forwarding of the received packet has been done,
namely, that an output instruction for a received packet in a control
plane is unnecessary.
[0025]
In the following d e s c r i p t i o n , the flow entry with Priority = 65535
10 and the flow entry with Priority = 60000 are flow entries (second
processing rule) set by the controller 20. The flow entry with Priority
= "a" is a flow entry for an Unknown Unicast (a flow entry for an
unknown packet) that is set in advance. Therefore, on receiving a
packet, the switch 10-1 performs checking of the received packet with
15 flow entries in the p r i o r i t y order of the flow table of FIG. 5, and where
there is a match with the flow entry with Priority = 65535 or the flow
entry with P r i o r i t y = 60000, processing determined in the action field of
the respective flow entries is performed. On the other hand, for a
packet that matches neither the flow entry with Priority = 65535 nor the
20 flow entry with Priority = 60000, flooding processing in accordance
with a flow entry for an Unknown Unicast (flow entry for an unknown
packet) and transmission of a Packet-in (forwarding done) to the
c o n t r o l l e r 20 are performed.
[0026]
25 This type of switch 10-1 can be realized by flooding processing
when there is a match, with the abovementioned low priority, in an
OpenFlow switch of Non Patent Literature 1 or 2, and by setting a flow
entry for an Unknown Unicast (flow entry for an unknown packet) that
performs transmission of a Packet-in message (forwarding done) to the
30 controller 20. It is to be noted that since the switches 10-2 and 10-3
have a configuration (content (target flow, executed action and the like)
of the flow entry storage unit differs as appropriate) similar to the
abovementioned switch 10-1, a d e s c r i p t i o n is omitted.
[0027]
10
With regard to the controller 20 of FIG. 3 and FIG. 4, in the
OpenFlow controller of Non Patent Literature 1 and 2, on receiving a
Packet-in message (forwarding done) a path calculation or flow entry
s e t t i ng operation is performed, but implementation is possible by
5 adding a function to discard packets included in the Packet-in message
(forwarding done), without giving a packet output instruction to a
switch (in the following, where a switch is not particularly
d i s t i n g u i s h e d , "switch 10" is i n d i c a t e d ).
[0028]
10 It is to be noted that functions of the switch 10 and the controller
20 shown in FIG. 3 and FIG. 4 may also be realized in a computer
i n s t a l l e d in these apparatuses, using hardware thereof, by a computer
program that executes the respective processing described above.
[0029]
15 Next, a detailed d e s c r i p t i o n is given concerning operations of the
present exemplary embodiment, making reference to the drawings. The
following description cites an example in which data is transmitted to
the client 40 from the server 30 in FIG. 3. In an initial state, only a
flow entry for an Unknown Unicast with Priority = "a" (note that a value
20 is set for "a" that is smaller than the Priority of flow entries set by the
c o n t r o l l e r 20) is set in the flow table of FIG. 5.
[0030]
FIG. 6 is a sequence diagram representing operations of the first
exemplary embodiment of the invention. As shown in FIG. 6, first,
25 when an initial packet is t r a n s m i t t e d from the server 30 to the client 40
(S001 in FIG. 6), the packet is received at port 0/bb of the switch 10-1.
[0031]
The switch 10-1 retrieves a flow entry having a match condition
( r e t r i e v e condition) that matches a packet received from the server 30.
30 At this point in time, since a flow entry with Priority = 65535 and a
flow entry with Priority = 60000 are not set, a match occurs with a flow
entry with Priority = "a" (S002 in FIG. 6). In this case, the switch
10-1 follows the content of the action field of the flow entry (flow entry
for an Unknown Unicast) with Priority = "a", to perform flooding
11
processing (S003 in FIG. 6) and Packet-in (forwarding done)
transmission (S004 in FIG. 6).
[0032]
It is to be noted that, while omitted in FIG. 6, processing similar
5 to that of switch 10-2 is performed, and a packet transmitted from the
server 30 is forwarded to the client 40 via the switch 10-2.
[0033]
Meanwhile, the controller 20 that receives the control message
Packet-in (forwarding done) recognizes that this is a Packet-in
10 (forwarding done), not a normal Packet-in, and starts path calculation
and flow entry creation, but a packet output instruction (Packet-out)
using a packet included in the Packet-in (forwarding done) or packet
information is not performed (S005 in FIG. 6).
[0034]
15 Below, on receiving a packet from the server 30, the switch 10-1
follows the content of the action field of the flow entry (flow entry for
an Unknown Unicast) with Priority = "a", to perform flooding
processing (S003 in FIG. 6) and Packet-in (forwarding done)
transmission (S004 in FIG. 6).
20 [0035]
Thereafter, as shown in FIG. 7, when the controller 20 creates a
Unicast flow entry (UC flow entry) (S103 in FIG. 7), the controller 20
sets the created Unicast flow entry (UC flow entry) for switch 10-1 and
switch 10-2 (S104 in FIG. 7; flow-mod).
25 [0036]
Setting of the Unicast flow entry (UC flow entry) is completed,
and thereafter, on receiving a packet from the server 30, the switches
10-1 and 10-2 perform Unicast forwarding in accordance with the
Unicast flow entry (UC flow entry) (S105 in FIG. 7).
30 [0037]
As described above, according to the present exemplary
embodiment, even if packets exceeding the processing capability of the
switch 10 and the controller 20 are generated, packet order reversal and
packet loss occurrence are effectively inhibited. A reason for this is
12
that the configuration is such that flooding and Packet-in (forwarding
done) transmission to the controller are performed by the flow entry for
an Unknown Unicast, a packet transmission instruction is given via the
control plane by the controller, and packet output processing
5 accompanying this is inhibited.
[0038]
[Second Exemplary Embodiment]
Next, a description is given concerning a second exemplary embodiment
of the present invention in which a function is added to the switch 10
10 described above, and Packet-in (forwarding done) transmission itself is
i n h i b i t e d . Since the present exemplary embodiment is realized by a
configuration similar to the first exemplary embodiment described
above, the description below is centered on points of difference in
operations thereof.
15 [0039]
FIG. 8 is a sequence diagram representing operations of the
second exemplary embodiment of the invention. Basic operations of
the switch 10 and controller 20 are similar to the first exemplary
embodiment, but as shown on the left edge of FIG. 8, after the switch 10
20 transmits a first control message Packet-in (forwarding done), for a
predetermined time, second and subsequent Packet-in (forwarding done)
t r a n s m i s s i o n s are inhibited. It is to be noted that the predetermined
time can be calculated from system scale, assumed flow type, and the
l i k e .
25 [0040]
Specifically, when the first packet is received, the switch 10-1
follows the content of the action field of a flow entry (flow entry for an
Unknown Unicast) with Priority = "a", to perform flooding processing
(S003 in FIG. 8) and Packet-in (forwarding done) transmission (S004 in
30 FIG. 8). However, thereafter, until a predetermined time elapses, if a
subsequent packet is received, flooding processing (S003 in FIG. 8) is
performed but Packet-in (forwarding done) transmission (S004 in FIG.
8) is stopped.
[0041]
13
When the predetermined time elapses, the switch 10 performs
flooding processing (S003 in FIG. 8) and Packet-in (forwarding done)
transmission (S004 in FIG. 8). Thereafter, until the predetermined
time elapses, even if data forwarding is performed, the Packet-in
5 (forwarding done) transmission is stopped.
[0042]
As described above, according to the present exemplary
embodiment it is possible to inhibit load increase on the switch 10 and
the controller 20 even more than in the first exemplary embodiment.
10 According to the present exemplary embodiment, since adjustment of
Packet-in (forwarding done) transmission interval is enabled, it is
possible to economize on resources (memory, CPU and the like).
[0043]
In the abovementioned exemplary embodiment, a description was
15 given where, after transmission of a first control message Packet-in
(forwarding done), for a predetermined time, second and subsequent
Packet-in (forwarding done) transmissions are inhibited, but instead of
a predetermined time, the number of times a target packet for control
message Packet-in (forwarding done) is received, or data amount, may
20 be used. In this case, after transmission of the control message
Packet-in (forwarding done), the switch 10 inhibits the control message
Packet-in (forwarding done), until the number of times a packet is
received or the data amount exceed a predetermined threshold.
Thereafter when the number of times a packet is received or data amount
25 exceed the predetermined threshold, the switch 10 resets values thereof,
and transmits the control message Packet-in (forwarding done). It is
to be noted that the number of times a packet is received or the data
amount can be implemented by providing a flow s t a t i s t i c a l information
field (Counter), similar to flow entries described in Non Patent
30 Literature 1 and 2.
[0044]
A d e s c r i p t i o n of exemplary embodiments of the present invention
have been given above, but the invention is not limited to the
abovementioned exemplary embodiments, and further modifications,
14
s u b s t i t u t i o n s and adjustments may be added within a scope that does not
depart from fundamental technical concepts of the invention. For
example, although the abovementioned exemplary embodiments are not
p a r t i c u l a r l y limited, in view of the advantages of the present invention
5 as described above, besides u t i l i z a t i o n in data centers, the invention
may be preferably applied to sequencing, image d i s t r i b u t i o n service or
TV telephony services in which packet loss effects are large.
[0045]
In the abovementioned exemplary embodiments, a description was
10 given in which flooding processing is performed, but it is also possible
to calculate end-to-end paths where communication is expected to occur
giving c o n s i d e r a t i o n to network topology, and to set flow entries so as
to perform packet forwarding following these paths.
[0046]
15 Although omitted in the abovementioned exemplary embodiments,
i t is also possible to restrict whether or not to allow flooding
processing in accordance with security level ( a u t h e n t i c a t i o n state or the
like) of a connection destination, or flooding target region (limitation
of UDP (User Datagram Protocol) packets and the like). These can be
20 realized by r e w r i t i n g matching conditions (retrieval conditions) of flow
entries for an Unknown Unicast (flow entries for unknown packets), by
the controller 20. In this way, it is possible to switch control in
accordance with connection destination and state thereof.
[0047]
25 In the first exemplary embodiment and the second exemplary
embodiment described above, a description was given in which the
controller 20 controls the switch 10, but a control target can also be a
communication apparatus such as a mobile telephone terminal, a smart
phone, a tablet t e r m i n a l , a personal computer, a game console, a mobile
30 router or the like, that hold flow entries as described above, and in
accordance with content thereof, process received packets or packets
from an i n s t a l l e d application. In this way, for example, it is possible
to inhibit load increase due to packets from a packet processor within a
apparatus, or packet order reversal.
15
[0048]
The first exemplary embodiment and the second exemplary
embodiment described above are also preferably operated giving
consideration to traffic volume and time slots, which are s t a t i s t i c a l ly
5 comprehended, rather than having continuous operation. For example,
it is possible to perform control allowing packet forwarding in a control
plane as in Non Patent Literature 1 and 2, during nighttime, holidays or
the like, when network monitoring level drops, and to perform
operations as in the first exemplary embodiment and the second
10 exemplary embodiment, in time slots where large amounts of data
communication occur or in states that enable strengthening of
monitoring commensurate with large amounts of data communication.
[0049]
Finally, preferred modes of the present invention are
15 summarized.
[Mode 1]
(Refer to the communication apparatus according to the first aspect.)
[Mode 2]
The communication apparatus according to Mode 1, wherein the
20 predetermined message is a control message that requests setting of a
second processing rule for packet(s) processed using the first
processing rule, with respect to the control apparatus.
[Mode 3]
The communication apparatus according to Mode 1 or Mode 2, wherein
25 the state n o t i f i c a t i o n unit t r a n s m i t s , in a case of receiving a packet that
matches neither the first nor the second processing rule, a second
control message requesting setting of the second processing rule and an
i n s t r u c t i o n to forward the packet, with respect to the control apparatus.
[Mode 4]
30 The communication apparatus according to any one of Modes 1 to 3,
wherein the state notification unit inhibits, after transmission of the
predetermined message, transmission of the predetermined control
message to the control apparatus, even if a packet is processed using the
first processing rule, until a predetermined condition is established.
16
[Mode 5]
The communication apparatus according to Mode 4, wherein the
predetermined condition is any of: elapse of a predetermined time,
receipt of more than a predetermined number of packets, and receipt of
5 a data amount greater than a predetermined amount.
[Mode 6]
The communication apparatus according to any one of Modes 1 to 5,
wherein the first processing rule is a processing rule for performing a
broadcast or a multicast, by predetermined path(s).
10 [Mode 7]
(Refer to the control apparatus according to the second aspect.)
[Mode 8]
(Refer to the communication system according to the third aspect.)
[Mode 9]
15 (Refer to the communication method according to the fourth aspect.)
[Mode 10]
(Refer to the control method of the communication apparatus according
to the fifth aspect.)
[Mode 11]
20 A program that executes on a computer installed in a communication
apparatus provided with a processing rule storage unit capable of
storing a first processing rule for unknown packets set in advance, and a
second processing rule set by a control apparatus, and a packet
processor that processes received packets based on processing rules
25 stored in the processing rule storage unit, the program including a
process of t r a n s m i t t i n g a predetermined control message to the control
apparatus when a packet is processed using the first processing rule,
and a process of continuing packet processing using the first processing
rule until the second processing rule is set by the control apparatus.
30 [Mode 12]
A program that executes on a computer i n s t a l l e d in a control apparatus
connected to a communication apparatus provided with a processing
rule storage unit capable of storing a first processing rule for unknown
packets set in advance, and a second processing rule set by a control
17
apparatus, a packet processor that processes received packets based on
processing rules stored in the processing rule storage unit, and a state
n o t i f i c a t i o n unit that transmits a predetermined control message to the
control apparatus when a packet is processed using the first processing
5 rule, a process of creating, on receiving the predetermined control
message from the communication apparatus, the second processing rule
to be set in the communication apparatus, and setting the second
processing rule in the communication apparatus, and a process of
discarding packets included in the control message.
10 It is to be noted that that the abovementioned Modes 7 to 12 may be
extended to Modes 2 to 6, similar to Mode 1.
[0050]
It is to be noted that the various disclosures of the
abovementioned Non Patent Literature are incorporated herein by
15 reference thereto. Modifications and adjustments of exemplary
embodiments and examples may be made within the bounds of the entire
d i s c l o s u r e (including the scope of the claims) of the present invention,
and also based on fundamental technological concepts thereof.
Furthermore, various combinations and selections of various disclosed
20 elements (including respective elements of the respective claims,
r e s p e c t i v e elements of the respective exemplary embodiments and
examples, respective elements of the respective drawings, and the like)
are possible within the scope of the claims of the present invention.
That is, the present invention clearly includes every type of
25 transformation and modification that a person skilled in the art can
r e a l i z e according to the entire disclosure including the scope of the
claims and to technological concepts thereof.
REFERENCE SIGNS LIST
[0051]
30 10-1 to 10-3 switch
10A communication apparatus
11 flow entry storage unit
11A processing rule storage unit
12, 12A packet processor
18
13 controller communication unit
13A state notification unit
20 controller
20A control apparatus
30 server
40 client
19
WE CLAIM:
1. A communication apparatus comprising:
a processing rule storage unit capable of storing a first
processing rule for unknown packets set in advance, and a second
processing rule set by a control apparatus;
5 a packet processor that processes received packets based on
processing rules stored in said processing rule storage unit; and
a state notification unit that transmits a predetermined control
message to said control apparatus when a packet is processed using said
first processing rule; wherein
10 said communication apparatus continues packet processing using
said first processing rule until said second processing rule is set by said
control apparatus.
2. The communication apparatus according to claim 1, wherein said
predetermined message is a control message that requests setting of a
second processing rule for packet(s) processed using said first
p r o c e s s i n g rule, with respect to said control apparatus.
3. The communication apparatus according to claim 1 or 2, wherein
said state notification unit transmits, in a case of receiving a packet
that matches neither said first nor said second processing rule, a second
control message requesting setting of said second processing rule and
5 an instruction to forward said packet, with respect to said control
apparatus.
4. The communication apparatus according to any one of claims 1 to
3, wherein said state notification unit inhibits, after transmission of
said predetermined message, transmission of said predetermined control
message to said control apparatus, even if a packet is processed using
5 said first processing rule, until a predetermined condition is established.
5. The communication apparatus according to claim 4, wherein said
predetermined condition is any of: elapse of a predetermined time,
receipt of more than a predetermined number of packets, and receipt of
a data amount greater than a predetermined amount.
6. The communication apparatus according to any one of claims 1 to
5, wherein said first processing rule is a processing rule for performing
20
a broadcast or a multicast, by predetermined path(s).
7. A control apparatus, connected to a communication apparatus that
i n c l u d e s :
a processing rule storage unit capable of storing a first
processing rule for unknown packets set in advance, and a second
5 processing rule set by a control apparatus,
a packet processor that processes received packets based on
processing rules stored in said processing rule storage unit, and
a state notification unit that transmits a predetermined control
message to said control apparatus when a packet is processed using said
10 first processing rule; wherein
said control apparatus creates, on receiving said predetermined
control message, said second processing rule to be set in said
communication apparatus and sets said second processing rule in said
communication apparatus, and also discards packets included in said
1 5 control message.
8. A communication system comprising: a communication apparatus
including
a processing rule storage unit capable of storing a first
processing rule for unknown packets set in advance, and a second
5 processing rule set by a control apparatus,
a packet processor that processes received packets based on
processing rules stored in said processing rule storage unit, and
a state notification unit that transmits a predetermined control
message to said control apparatus, when a packet is processed using
10 said first processing rule, wherein
said communication apparatus continues packet processing using
said first processing rule until said second processing rule is set by said
control apparatus; and
a control apparatus, connected to said communication apparatus,
15 that creates, on receiving said predetermined control message, said
second processing rule to be set in said communication apparatus and
sets said rule in said communication apparatus, and also discards
packets included in said control message.
21
9. A communication method wherein a communication apparatus that
includes a processing rule storage unit capable of storing a first
processing rule for unknown packets set in advance, and a second
processing rule set by a control apparatus, and a packet processor that
5 processes received packets based on processing rules stored in said
processing rule storage unit, performs:
a step of t r a n s m i t t i n g a predetermined control message to said
control apparatus when a packet is processed using said first processing
rule, and
a step of continuing packet processing using said first processing
rule until said second processing rule is set by said control apparatus.
10. A control method wherein a control apparatus, connected to a
communication apparatus that includes a processing rule storage unit
capable of storing a first processing rule for unknown packets set in
advance and a second processing rule set by a control apparatus, a
packet processor that processes received packets based on processing
rules stored in said processing rule storage unit, and a state notification
unit that transmits a predetermined control message to said control
apparatus when a packet is processed using said first processing rule,
performs:
a step of creating, on receiving said predetermined control
message from said communication apparatus, said second processing
rule to be set in said communication apparatus, and setting said second
processing rule in said communication apparatus, and
a step of discarding packets included in said control message.