JP6577718B2 - COMMUNICATION DEVICE, COMMUNICATION DEVICE CONTROL METHOD, AND PROGRAM - Google Patents

Description

  The present invention relates to a communication device, a communication device control method, and a program, and more particularly, to an IP address setting technique for a communication device having a plurality of communication interfaces.

  In recent years, techniques for simultaneously operating a plurality of communication interfaces have been developed. For example, there is a device that can simultaneously operate both a communication interface that operates as a terminal and a communication interface that operates as a base station in an infrastructure mode, which is one of wireless LAN operation modes compliant with the IEEE 802.11 standard. To do. In that case, since both communication interfaces are connected to different IP networks, the IP addresses are set independently.

  The IP address is composed of a network address part and a host address part. The network address indicates to which subnetwork the terminal belongs. The host address indicates which terminal on the subnetwork. The network address part and the host address part are determined by a netmask.

  Since the network address is determined for each subnetwork, the same network address may be set in different subnetworks. Therefore, in a device that uses a plurality of communication interfaces at the same time, the same network address may be set for the plurality of communication interfaces depending on the subnetwork to which each communication interface is connected.

  When a device connects to a network and transmits data, a communication interface used for data transmission is determined by a routing table. When the same network address is set for a plurality of communication interfaces, data transmission is performed via a communication interface with a high priority defined in the routing table. For this reason, data may be transmitted from an unintended communication interface.

  In order not to transmit data from an unintended communication interface, it can be realized by changing the network address assigned to the communication interface to a different network address.

  Japanese Patent Application Laid-Open No. 2004-133620 proposes a technique for automatically changing the network address setting when a duplication of network addresses assigned to each communication interface is detected in a device having a plurality of communication interfaces.

JP 2005-197793 A

  However, in the technique disclosed in Patent Document 1, if the network address is changed while communication data is being transmitted / received in the communication interface for changing the network address, the data communication is interrupted. For example, if data communication is interrupted while print data is being transmitted from a PC to a printer via a network, the print processing is stopped.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique for reducing interruptions in data communication.

In order to achieve the above object, a communication apparatus according to an aspect of the present invention includes the following arrangement. That is,
A communication apparatus comprising a first communication interface that operates as a wireless terminal and a second communication interface that operates as a wireless base station,
The network address of the first communication interface, determining means for determining whether said second network address of the communication interface overlap,
Storage means for storing the MAC address of another communication device requesting data communication before Symbol second communication interface,
A first notifying means for notifying the other communication device that the data communication is suspended when it is determined by the determining means to be duplicated;
After notification by the first notification means has been made, and setting means for setting a different network address, the second communication interface of the network address of the first communication interface,
After the setting is performed by the setting unit, the second communication device notifies the other communication device that the data communication is possible based on the MAC address of the other communication device stored by the storage unit. Notification means,
It is characterized by providing.

  According to the present invention, interruption of data communication can be reduced.

The figure which shows the structural example of the communication system which concerns on one Embodiment of this invention. 1 is a block diagram illustrating a configuration example of a communication device (printer) according to an embodiment of the present invention. 5 is a flowchart illustrating a procedure of processing performed by the communication apparatus according to the first embodiment. The address setting block diagram of each IF which concerns on one Embodiment of this invention. The address setting block diagram of each IF at the time of the network address duplication concerning one Embodiment of this invention. FIG. 3 is a processing sequence diagram of the communication apparatus according to the first embodiment. FIG. 9 is a processing sequence diagram of the communication apparatus according to the second embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The scope of the present invention is defined by the claims, and is not limited by the following individual embodiments.

(Embodiment 1)
<1. Configuration of communication system>
FIG. 1 shows a configuration example of a communication system according to an embodiment of the present invention. Reference numeral 101 denotes a printer to which the present invention can be applied, and is a communication apparatus having a wireless LAN function in accordance with IEEE 802.11. The printer 101 is a communication device that can operate simultaneously in the wireless base station mode and the wireless terminal mode. The base station mode is a mode in which the printer 101 operates as an AP (access point) in an infrastructure mode that is one of the operation modes of the IEEE 802.11 wireless LAN. On the other hand, the terminal mode is a mode in which the printer 101 operates as a wireless terminal in the infrastructure mode.

  The printer 101 can be connected to the network 106 through a terminal mode IF (interface) and to the network 107 through a base station mode IF. The printer 101 receives a print job via the networks 106 and 107 and performs a predetermined print process.

  Reference numeral 102 denotes an AP (access point) that relays between the network 106 and the network 108. The AP 102 has a DHCP server function and a function of distributing an IP address to a DHCP client. Reference numeral 103 denotes a PC (personal computer) that can transmit a print job to the printer 101 via the network 108, the AP 102, and the network 106.

  Reference numerals 104 and 105 denote PCs (personal computers) which can transmit print jobs to the printer 101 via the network 107 as wireless terminals. The PC 104 and the PC 105 have a DHCP client function and a function of requesting an IP address from the DHCP server.

  A wireless LAN network 106 is formed by the printer 101 and the AP 102. Reference numeral 107 denotes a wireless LAN network, which is formed by the printer 101, the PC 104, and the PC 105. Reference numeral 108 denotes a wired LAN network, which is formed by the AP 102 and the PC 103.

<2. Configuration of communication device>
Next, FIG. 2 shows a configuration example of a communication apparatus (printer) according to an embodiment of the present invention. Reference numeral 101 denotes the entire printer. A wireless communication control unit 201 controls communication by controlling an antenna and a circuit for transmitting and receiving wireless signals to and from other wireless devices via a wireless LAN. Reference numeral 202 denotes a transmission / reception unit that performs data transmission / reception control according to the protocol of each communication layer.

  Reference numeral 203 denotes an operation unit for operating the printer 101. The operation unit 203 includes operation buttons and the like for inputting to the printer 101. A display unit 204 performs various display processes such as outputting visually recognizable information such as an LCD (Liquid Crystal Display) or an LED (Light Emitting Diode).

  Reference numeral 205 denotes a control unit that controls the operation of the entire printer 101 by executing a control program stored in the storage unit 206, and includes one or a plurality of processors. A storage unit 206 includes a ROM and a RAM that store programs and data for controlling the printer 101. Various operations described later are performed by the control unit 205 executing a control program stored in the storage unit 206.

  A print processing unit 207 performs print processing based on a print instruction. The printing process includes paper feed and paper discharge processes. A base station mode operation unit 208 performs processing for the printer 101 to operate as an AP in the wireless LAN. A terminal mode operation unit 209 performs processing for the printer 101 to operate as a terminal station in a wireless LAN.

  A DHCP server unit 210 performs an IP address assignment process for a DHCP client that is to connect to a wireless LAN network while operating in the base station mode. A DHCP client unit 211 performs an IP address acquisition process for an AP in the wireless LAN network during operation in the terminal mode.

  An address duplication determination unit 212 determines whether the network addresses set in the base station mode IF and the terminal mode IF overlap each other. Reference numeral 213 denotes a data communication detection unit that detects that communication data transmission / reception processing is being performed in the base station mode IF. A data communication end determination unit 214 determines whether or not the data communication is ended when the data communication detection unit 213 detects the data communication.

  The functional units 208 to 214 are configured by software or hardware, respectively. When configured by software, these functional units are stored as computer programs in the storage unit 206, and each function is realized by the control unit 205 executing the programs.

<3. Processing performed by communication device>
In the present embodiment, a case will be described in which the printer 101 receives an IP address to be set as the terminal mode IF while the printer 101 is receiving a print job from the PC 104 in the base station mode IF.

  FIG. 3 is a flowchart showing a procedure of IP address assignment processing by the communication apparatus (printer 101) according to the present embodiment.

  First, the DHCP client unit 211 of the printer 101 performs an address acquisition process for acquiring from the AP 102 an IP address for setting the terminal mode IF (S301). Subsequently, the address duplication determination unit 212 compares the acquired network address of the IP address with the network address of the IP address already set in the base station mode IF, and determines whether or not the network address is duplicated. (S302).

  In S302, when the IP addresses set in the terminal mode IF and the base station mode IF are the contents shown in FIG. 4, the network addresses are 192.168.1.0 and 192.168.2.0, respectively. Therefore, it is determined that there is no duplication. On the other hand, if the IP addresses set in the terminal mode IF and the base station mode IF are the contents shown in FIG. 5, since the network addresses are both 192.168.1.0, it is determined that they are duplicated. .

  As a result of S302, when it is determined that there is no duplication, the DHCP client unit 211 sets the IP address acquired in S301 to the terminal mode IF (S308). On the other hand, if it is determined as a result of S302 that there is an overlap, the data communication detection unit 213 determines whether data communication is being performed using the IF in the base station mode (S303). Here, the data includes a print job. In the present embodiment, a case where the communication data is a print job will be described, but the present invention is not limited to this.

  As a result of S303, when it is determined that data communication is being performed, the data communication end determination unit 214 determines whether or not the data communication has ended (S304). The end of data communication is the timing when a print job end notification is received, but is not limited to this.

  If it is determined in S304 that the data communication is completed, or if it is determined in S303 that the data communication is not being performed, the DHCP server unit 211 sets the IP address of the network address different from the network address of the IP address acquired in S301 to the base station mode. (S305).

  Then, by restarting the base station mode, the communication link between the printer 101 and the PC 104 is disconnected and re-established (S306). Since the DHCP process is executed again by the process of S306, the IP address having the same network address as the IP address set in S305 can be redistributed to the PC 104 (S307). After S307, the IP address acquired in S301 is set as the IF of the terminal mode (S308).

  When the above processing is completed, a different network address can be set for the communication IF in each mode, and data communication is enabled using each communication IF.

<4. Processing sequence between communication device and peripheral device>
FIG. 6 shows that when a network address set in each IF of the communication apparatus (printer 101) is duplicated, an IP address having a different network address is set in each IF when data communication is being performed in the IF of the base station mode. FIG.

  First, the printer 101 receives a print request from the PC 104 and starts data communication for processing a print job (S601). In the present embodiment, the data communication start sequence is set to the timing of S601. However, the timing is not necessarily required. Data communication may be started before the timing of S604 described later, and data communication using the base station mode IF may be in progress in S604.

  Next, the printer 101 acquires an IP address for setting the terminal mode IF from the AP 102 (S602). The network address of the IP address is compared with the network address of the IP address already set in the IF of the base station mode, and it is determined whether or not they are duplicated (S603).

  If it is determined in S603 that they are duplicated, it is determined whether data communication is being performed using the IF in the base station mode (S604). As a result of S604, when it is determined that data communication is being performed, the data communication end is awaited (S605). After confirming the end of the data communication (S606), an IP address having a network address different from the network address of the IP address acquired in S602 is set in the base station mode IF (S607).

  Then, by restarting the base station mode (S608), the communication link between the printer 101 and the PC 104 is disconnected (S609) and re-established (S610). When the communication link is re-established in S610, the PC 104 performs an IP address acquisition process using DHCP for the base station mode IF of the printer 101 (S611). The PC 104 sets the IP address acquired in S611 (S612). After the DHCP processing in S611, the printer 101 sets the IP address acquired in S602 in the terminal mode IF (S613).

  As described above, the interruption of data communication can be reduced by controlling the IP address change timing according to whether or not data communication is being performed in the communication IF that changes the network address.

(Embodiment 2)
In the present embodiment, a case where a print request is received from the PC 105 while the printer 101 is processing a print job from the PC 104 will be described. In this embodiment, by not processing a new print job after duplication of network addresses, an IP address is set in the IF of the terminal mode after the processing of the print job processed when it is determined that data communication is in progress. The apparatus configuration is the same as that described in the first embodiment, and a description thereof will be omitted.

  FIG. 7 shows a case where the printer 101 requests a print request from the PC 105 when the communication apparatus (printer 101) is waiting for the end of data communication in the base station mode IF of the printer 101 after confirming the duplication of the network address set in each IF. FIG.

  Since the processing from S701 to S704 is the same as the processing from S601 to S604, description thereof is omitted. As a result of determining that the data communication is being performed in S704, the printer 101 enters the data communication end waiting state, but receives a print request from the PC 105 in this state (S705).

  In response to the print request in step S705, the printer 101 notifies the PC 105 of a message that the print job processing from the PC 105 is suspended until after the restart (S706). In step S <b> 706, the printer 101 stores the MAC address of the PC 105 in order to notify the PC 105 that the print job can be processed in step S <b> 716 described later.

  Since the processing from S707 to S710 is the same as the processing from S605 to S608, the description thereof is omitted. After the restart of S710, the communication link between the PC 104 and the PC 105 with the printer 101 is disconnected (S711) and re-established (S712). When the communication link is re-established in S712, the PC 104 and the PC 105 perform an IP address acquisition process by DHCP for the base station mode IF of the printer 101 (S713). The PC 104 and PC 105 set the IP address acquired in S713 (S714). After the DHCP processing in S713, the printer 101 sets the IP address acquired in S702 in the terminal mode IF (S715).

  Next, the printer 101 notifies the PC 105 that has notified the message that the print job processing is suspended in S706 that the print job can be processed (S716). In order to notify the PC 105 that the print job can be processed in S716, it is necessary to acquire the IP address reset in the PC 105 in S714. The IP address reset in the PC 105 can be acquired by comparing the MAC address of the terminal group that performed the DHCP process in S713 with the MAC address of the PC 105 stored in S706.

  As a result of comparing the MAC addresses, it can be determined that the terminal having the matched MAC address is the PC 105, and the IP address leased by the DHCP process for the matched MAC address is determined as the IP address reconfigured in the PC 105, and acquired. be able to. Further, the IP address reset in the PC 105 may be obtained by RARP (Reverse Address Resolution Protocol) based on the MAC address of the PC 105 stored in S706.

  Then, data communication for performing printing processing between the printer 101 and the PC 105 is started (S717).

  As described above, in this embodiment, a new print job is not accepted, and an IP address is set in the terminal mode IF after the processing of the print job already received when it is determined that data communication is in progress. Can do.

  According to the present invention, since the change timing of the IP address is controlled in the communication interface for changing the network address according to whether or not data communication is being performed, the interruption of the data communication can be reduced.

  In each embodiment of the present invention, communication data has been described as a print job, but the present invention is not limited to this. For example, a unicast packet addressed to the printer 101 (address set to the wireless base station) may be used as communication data.

  In each embodiment of the present invention, the determination of the end of data communication has been described as a case where a print job end notification is received, but the present invention is not limited to this. For example, when the printer 101 transmits / receives a TCP FIN packet, the printer 101 may transmit / receive a UPnP ssdp: byebye message. Alternatively, it may be determined that the data communication is completed, for example, at a timing when it is detected that the PC 104 which is the partner terminal of the data communication has left the network 106.

  In each embodiment of the present invention, the communication link is disconnected and re-established by restarting the function of the base station mode. However, the present invention is not limited to this. The disconnection / re-establishment of the communication link may be realized by changing the wireless channel used in the network 106 by the printer 101 or by transmitting a deauthentication frame to the PC 104 and the PC 105 by the printer 101.

  In each embodiment of the present invention, the network address duplication check is performed when the terminal mode IF is activated, but may also be performed when the terminal mode IF is stopped. Specifically, the IP address set in the IF when the terminal mode IF was operating at least immediately before is stored even after the terminal mode IF has stopped. When the base mode IF is started while the terminal mode IF is stopped, the network address of the IP address (the stored IP address) set in the terminal mode IF is confirmed. To do. Then, an IP address of a network address different from the confirmed network address is set when the base station mode IF is activated. By doing so, although the duplication confirmation is always required once, the possibility of restarting the base station mode can be reduced.

  In each embodiment of the present invention, when it is determined that data communication is being performed using the IF of the base station mode, the acquired IP address is temporarily released to set the IF of the terminal mode, and the base station mode is restarted Later, the IP address may be acquired again. As a result, the IP address that can be distributed by the AP 102 can be increased by one during data communication.

(Other embodiments)
The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in a computer of the system or apparatus read and execute the program This process can be realized. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

  101: Printer, 102: AP, 103, 104, 105: PC, 106, 107, 108: Network, 201: Wireless communication control unit, 202: Transmission / reception unit, 203: Operation unit, 204: Display unit, 205: Control unit 206: Storage unit 207: Print processing unit 208: Base station mode operation unit 209: Terminal mode operation unit 210: DHCP server unit 211: DHCP client unit 212: Address duplication determination unit 213: Data communication Detection unit 214: Data communication end determination unit

Claims (10)

A communication apparatus comprising a first communication interface that operates as a wireless terminal and a second communication interface that operates as a wireless base station,
The network address of the first communication interface, determining means for determining whether said second network address of the communication interface overlap,
Storage means for storing the MAC address of another communication device requesting data communication before Symbol second communication interface,
A first notifying means for notifying the other communication device that the data communication is suspended when it is determined by the determining means to be duplicated;
After notification by the first notification means has been made, and setting means for setting a different network address, the second communication interface of the network address of the first communication interface,
After the setting is performed by the setting unit, the second communication device notifies the other communication device that the data communication is possible based on the MAC address of the other communication device stored by the storage unit. Notification means,
A communication apparatus comprising: The communication apparatus according to claim 1, further comprising address acquisition means for acquiring a network address of the first communication interface. After setting by said setting means, according to claim 1 or 2, further comprising a cutting means for cutting the communication link with the connected the another communication device via the second communication interface Communication device. Said cutting means, by restarting the radio base station, according to claim 3, characterized by disconnecting the communication link with the connected the another communication device via the second communication interface Communication equipment. The disconnecting means disconnects a communication link with the other communication device connected via the second communication interface by changing a channel of a network formed by the radio base station. The communication apparatus according to claim 3 . Said cutting means, by transmitting the Deauthentication frame to the radio base station from said another communication device, to disconnect the communication link with the connected the another communication device via the second communication interface The communication apparatus according to claim 3 , wherein: The data communication, the communication device according to any one of claims 1 to 6, characterized in that the communication for the printing process performed by the communication device. The data communication, said communication apparatus and said another communication apparatus according to any one of claims 1 to 6, characterized in that the communication performed by using a packet of unicast between the communication device . A method for controlling a communication device comprising a first communication interface that operates as a wireless terminal and a second communication interface that operates as a wireless base station,
Determining means, and the network address of the first communication interface, and whether the determination step of determining the network address of the second communication interface is duplicated,
A storage step storing means, for storing a MAC address of another communication device requesting data communication before Symbol second communication interface,
A first notifying step of notifying the other communication device that the data communication is suspended when it is determined that the first notifying unit is duplicated by the determining step;
Setting means, after the notification by the first notification step is performed, a setting step of the different network addresses is a network address of the first communication interface is set to the second communication interface,
After the second notification means has been set by the setting step, the other notification means that the data communication has become possible based on the MAC address of the other communication device stored by the storage step. A second notification step of notifying the communication device;
To that control method characterized in that it has a. Program for executing the steps of the control method according to the computer to claim 9.

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