JP2013077892A - Network controller and wake-up control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a network controller capable of performing an efficient power-saving operation in a network system corresponding to WOL that employs an activation method by a Wake Up Frame, and to provide a wake-up control method.SOLUTION: A network controller included in an information processing device has: a packet transmission/reception part transmitting/receiving a packet; and a packet analysis part outputting a wake-up request signal for activating the information processing device from a power-saving state in the case that a data pattern of the packet received by the packet transmission/reception part is accorded with a specific data pattern that is preliminarily set. The packet transmission/reception part periodically transmits a GARP (Gratuitous Address Resolution Protocol) packet by broadcasting when the information processing device is in the power-saving state.

Description

  The present invention relates to a network controller having a function for starting an information processing apparatus such as a printing apparatus from a power saving state.

  As a technique for remotely starting an information processing apparatus such as a printing apparatus in a power saving state from the outside via a LAN (Local Area Network), there is a Wake On LAN (hereinafter simply referred to as “WOL”). In WOL, as a method for starting an information processing apparatus compatible with WOL from a power-saving state, two types, a startup method using Magic Packet and a startup method using Wake Up Frame, are widely known.

FIG. 5 is a diagram illustrating a configuration example of a conventional information processing apparatus corresponding to WOL.
The information processing apparatus 101 illustrated in FIG. 5 includes a network controller 102, a power supply control unit 103, and a processing unit 104. The network controller 102 is a NIC (Network Interface Card) having a function for starting the information processing apparatus 101 from the power saving state, and includes a packet transmission / reception unit 105 and a packet generation / analysis unit 106. The packet transmission / reception unit 105 transmits / receives packets via a LAN (Ethernet (registered trademark)). The packet generation / analysis unit 106 generates a packet to be transmitted by the packet transmission / reception unit 105, analyzes a packet received by the packet transmission / reception unit 105, and the like. Also, as a result of analyzing the received packet, if the data pattern of the packet matches a specific data pattern set in advance, a signal of a wake-up request (“Wake Up request”) is sent to the power supply control unit 103. Send to. The power supply control unit 103 performs power supply control of the information processing apparatus 101 such as shifting the information processing apparatus 101 from the activated state to the power saving state or returning the information processing apparatus 101 from the power saving state to the activated state. For example, when the power control unit 103 receives a power saving request signal from a control unit (not shown) of the information processing apparatus 101, the power control unit 103 performs power control for shifting the information processing apparatus 101 from the activated state to the power saving state. Note that the power saving request signal is a signal output when, for example, no operation or processing is performed in the information processing apparatus 101 for a certain period of time. Further, for example, when receiving a wake-up request signal from the packet generation / analysis unit 106, the power control unit 103 performs power control for returning the information processing apparatus 101 from the power saving state to the activated state. When the power control unit 103 performs power control for shifting the information processing apparatus 101 from the activated state to the power saving state, the information processing apparatus 101 supplies power only to the minimum necessary unit including the network controller 102. It becomes a state (energized state) and enters a state where no power is supplied to other units (non-energized state). On the other hand, when the power supply control unit 103 performs power supply control for returning the information processing apparatus 101 from the power saving state to the start state, the unit that has been turned off in the power saving state is turned on in the information processing apparatus 101. Is done. The processing unit 104 performs various processes.

  When the information processing apparatus 101 is compatible with WOL that employs a startup method using Magic Packet, when the information processing apparatus 101 in the power saving state receives a packet having a specific data pattern called Magic Packet, Restore power and start up.

FIG. 6 is a diagram illustrating an example of the data pattern of the Magic Packet.
In the Magic Packet shown in FIG. 6, the MAC (Media Access Control) address of the device to be activated is set to 16 after 0xFF having a destination address of 6 bytes, that is, the broadcast address “FF-FF-FF-FF-FF-FF”. It has a data pattern repeated twice.

  On the other hand, when the information processing apparatus 101 is compatible with the WOL adopting the Wake Up Frame activation method, the information processing apparatus 101 in the power saving state matches a specific data pattern preset in the network controller 102. When a packet is received, it recovers its own power and starts up. The difference from the case of the activation method using Magic Packet is that the received packet is compared with a preset data pattern.

FIG. 7 is a diagram illustrating a comparison between a received packet and a preset data pattern, which is performed when the activation method based on the Wake Up Frame is adopted.
In FIG. 7, reference numeral 111 denotes a TCP / IP (Transmission Control Protocol / Internet Protocol) packet, which is an example of a received packet. The data structure of the packet includes an Ethernet (registered trademark) header portion (14 bytes), an IP header portion ( 20 bytes), a TCP header part (20 bytes), and a data part. Reference numeral 112 denotes a specific data pattern preset (set to “wake up”) in the packet generation / analysis unit 106 of the network controller 102, and the MAC address and destination of its own as the destination MAC address. It has its own IP address and destination port number as an IP address. Here, as an example, assuming that the information processing apparatus 101 is a printing apparatus, the destination port number is an lpr (line printer daemon protocol) port. In this case, when the information processing apparatus 101 receives the TCP / IP packet 111, it is preset in the Ethernet (registered trademark) header part, IP header part, TCP header part, and packet generation / analysis part 106 of the packet. A specific data pattern 112, that is, its own MAC address, its own IP address, and its lpr port are compared, and if they match, a packet generation / analysis unit 106 outputs a wakeup request signal, Recovers its own power and starts up. Note that comparison with other parts of the received packet is not performed.

  By the way, in a network system compatible with WOL, such as an office network system or an Internet system, the network is generally divided into subnets. In such a case, a node that issues a wake-up instruction and a target power-saving node may be partitioned by a route control device such as a router or a gateway (hereinafter collectively referred to as a “router”). There are many.

FIG. 8 is a diagram illustrating an example of a network system in such a case.
In the network system 121 illustrated in FIG. 8, the network is divided into two subnets A and B by the router 122. Nodes A1 to A4 and the router 122 are connected to the subnet A, and nodes B1 to B4 and the router 122 are connected to the subnet B. In such a network system 121, for example, when the node A1 issues a wake-up instruction (“Wake Up instruction”) to the node B4 to start the node B4 from the power saving state, the connection between the node A1 and the node B4 is It will be partitioned by the router 122. Each of the nodes A1 to A4 and the nodes B1 to B4 is, for example, the information processing apparatus illustrated in FIG.

  When the network system 121 is compatible with the WOL adopting the activation method by the Magic Packet, the Magic Packet is a broadcast packet as shown in FIG. Therefore, for example, the Magic Packet transmitted from the node A1 as a wake-up instruction is not delivered to the node B4 in the subnet B across the router 122.

  In order to solve this, a method of using a special router capable of relaying a Magic Packet is also conceivable. However, since such a router is not common, it is used only in a specific application environment. is the current situation. Therefore, it cannot be said that a network system compatible with WOL that employs a startup method based on Magic Packet is a realistic method in a medium-scale or larger network environment such as an office.

  On the other hand, when the network system 121 is compatible with the WOL adopting the Wake Up Frame activation method, a packet transmitted as a wake-up instruction from the node A1 is a normal packet, for example, a packet 111 in FIG. Since it has the same packet structure as the packet used in communication, if the setting of the router 122 that monitors the communication packet is appropriate, it becomes possible to issue a wake-up instruction to the node B 4 across the router 122. It can be said that this is a realistic method in a medium or larger network environment such as an office.

  Many network controllers that support the WOL adopting the Wake Up Frame activation method can set a plurality of specific patterns as predetermined specific patterns. According to a node equipped with such a network controller, for example, it does not wake up (ignore) for an http (hyper text transfer protocol) request, but for an lpr or ftp (file transfer protocol) request. Can set detailed wake-up conditions such as wake-up.

  Here, an example of communication in the network system 121 shown in FIG. 8 will be described in more detail using TCP / IP communication as an example. In this case, an IP address and a MAC address are used for communication. The IP address is a logical number that can be individually assigned to each node, and the MAC address is a physical number that is uniquely assigned to each device.

  An application executed in each node performs communication using an IP address, but a MAC address is used in a packet used for actual communication. Therefore, in TCP / IP communication, a protocol called ARP (Address Resolution Protocol) is prepared in order to check the MAC address of the communication partner. That is, when a node that performs communication designates an IP address and broadcasts an ARP packet, the node having the corresponding IP address returns an ARP response packet to which its own MAC address is added.

FIG. 9 is a diagram illustrating a communication example when an ARP packet is broadcast. However, in FIG. 9, only a part of the network system 121 is shown for convenience of explanation.
As shown in FIG. 9, for example, in order for the node A1 in the subnet A to know the MAC address of the node that is the communication partner, the IP address “192.168.1.3” of the node that is the communication partner is specified and the ARP packet ( When the ARP request is broadcast (S101), the node A3 having the corresponding IP address “192.168.1.3” returns an ARP response packet with its own MAC address added (S102).

  As described above, the node that performs communication can know the MAC address of the communication partner by broadcasting the ARP packet by designating the IP address of the node that is the communication partner.

  However, since each node performs such an exchange for each communication, it is inefficient. Therefore, in actual operation, a relation table (hereinafter referred to as “entry”) of an IP address and a MAC address of a communication partner is used. Is stored in its own memory as a table. This is called an ARP table.

FIG. 10 is a diagram illustrating an example of the ARP table.
As shown in FIG. 10, in the ARP table, the IP address (“Internet Address”) and the MAC address (“Physical Address”) of the other party that performed communication are stored in association with each other. According to the ARP table shown in FIG. 10, for example, the MAC address of the node whose IP address is “192.168.1.2” is “00-19-d1-13-cb-a1”.

  Each node keeps such an ARP table in its own memory, so that an application executed on each node refers to the ARP table prior to communication and includes an entry of a communication partner. If so, communication can be performed using the MAC address according to the entry. On the other hand, if no entry is included in the ARP table, an ARP packet (ARP request) is broadcast prior to communication to acquire the MAC address of the communication partner, and communication is performed using the MAC address.

  Each node deletes an entry that has not been used for a certain period of time in the ARP table held in the memory in order to efficiently use its own memory.

  In the network system 121 shown in FIG. 8, when communication is performed with a partner beyond the router 122, such as communication between the node A1 and the node B4, the router 122 relays the packet. Similarly to each node, the router 122 also holds the IP address and MAC address entry of the communication partner (relay destination) in its own memory as an ARP table. Of course, when the entry of the MAC address of the communication partner is not included in the ARP table, the router 122 acquires the MAC address by broadcasting the ARP packet (ARP request), and stores the entry in its own memory. Add to the retained ARP table.

FIG. 11 is a diagram showing an example of the ARP table held in the memory of the router 122 in this way.
As shown in FIG. 11, an ARP table is stored in the memory of the router 122 for each subnet. That is, the ARP table 131 on the subnet A side and the ARP table 132 on the subnet B side are held. The ARP table 131 on the subnet A side includes entries for IP addresses (“Internet Address”) and MAC addresses (“Physical Address”) of the nodes A1 to A4 belonging to the subnet A. The ARP table on the subnet B side includes entries for IP addresses (“Internet Address”) and MAC addresses (“Physical Address”) of the nodes B1 to B4 belonging to the subnet B.

  Here, it is assumed that the network system 121 is compatible with WOL that employs the Wake Up Frame activation method, and the network controller included in the node B2 is set to wake up only for lpr and ftp requests. Then, it is assumed that the node B2 is in a power saving state.

  FIG. 12 and FIG. 13 are diagrams illustrating a communication example when the node A1 makes an lpr or ftp request to the node B2 in such a case. However, for convenience of explanation, FIGS. 12 and 13 show only a part of the network system 121, and FIG. 13 shows only a part of the ARP table 132 on the subnet B side.

  As shown in FIG. 12, the node A1 makes an lpr or ftp request to the node B2, which is in a power saving state after setting to wake up only for the lpr and ftp requests. And In this case, although the node A1 and the node B2 are in different subnets, as shown in FIG. 13, the ARP table 132 on the subnet B side held by the router 122 includes an entry for the node B2. The packet related to the lpr or ftp request transmitted from A1 is relayed to the node B2 by the router 122 according to the ARP table 132. Then, the Node B 2 that has received the packet starts up from the power saving state according to the wake-up setting.

On the other hand, if the entry of the node B2 is not included in the ARP table 132 on the subnet B side held by the router 122, the following communication is performed.
FIG. 14 is a diagram illustrating an example of communication in such a case.

  As shown in FIG. 14, first, the node A1 makes an lpr or ftp request to “192.168.2.2”, which is the IP address of the node B2 in the power saving state (S201). In this case, since the entry of node B2 is not included in the ARP table 132 on the subnet B held by the router 122, the router 122 obtains the subnet B to which the node B2 belongs in order to obtain the MAC address of the node B2. In response to this, an ARP request is broadcast (S202). However, since the node B2 is set to wake up only for the lpr and ftp requests, it does not start up from the power saving state in response to the ARP request, and does not return an ARP response packet (S203). Therefore, in such a case, since the router 122 cannot obtain the MAC address of the node B2, the communication related to the lpr or ftp request from the node A1 to the node B2 fails.

  Thus, in order to prevent such communication failure, a method of setting the network controller of the node B2 to wake up also for the ARP request is conceivable. However, when such a method is adopted, if there is a request addressed to a node belonging to subnet B that does not include an entry in the ARP table 132 on the subnet B side, router 122 goes to subnet B each time. Since the ARP request is broadcast, the node B2 in the power saving state starts up each time, and as a result, the node B2 cannot perform efficient power saving operation.

  By the way, as an example of a network system, for example, in order to realize duplication of a SIP (Session Initiation Protocol) server with an inexpensive configuration, two SIP servers are connected by two different networks (communication LAN and maintenance LAN). A system is known in which both service IP addresses are the same (for example, see Patent Document 1). In this system, any server operating as an SIP server operating system sends out a GARP (Gratuitous Address Resolution Protocol) packet to all host computers connected to the communication LAN, thereby providing a service IP address. Can be associated with the active server, so that the client terminal only needs to refer to one service IP address when enjoying the SIP service.

  As an example of a network controller, for example, a network in which each packet is compared with first data and second data while a PC (Personal Computer) is in a sleep state in order to easily realize remote wakeup. A controller is known (see, for example, Patent Document 2). Here, the first data indicates the data pattern of the ARP request packet addressed to the network controller, and the second data indicates the data pattern of the wake-up packet addressed to the network controller. In this network controller, when the incoming packet matches the first data, the transmission data stored in the transmission data register is transmitted as an ARP response packet on the LAN, and when the incoming packet matches the second data, the network controller wakes up. Output a signal.

JP 2007-142976 A JP 2008-301077 A

  Conventionally, in a network system compatible with WOL that employs a startup method based on Wake Up Frame, there has been a problem that efficient power-saving operation cannot be performed as described above.

  Therefore, the present invention provides a network controller and a wakeup control method capable of performing efficient power saving operation in a network system compatible with WOL that employs a startup method based on a Wake Up Frame.

  According to the present invention, there is provided a network controller provided in an information processing apparatus, wherein a unit data transmission / reception unit that transmits / receives unit data (for example, a packet) and a data pattern of unit data received by the unit data transmission / reception unit are A unit data analysis unit that outputs a wake-up request signal for starting the information processing apparatus from the power saving state when it matches a preset specific data pattern. Provided is a network controller characterized in that when a processing device is in a power saving state, information for preventing entry information of an address resolution protocol table interposed on the network from being refreshed and cleared is transmitted at a predetermined time. Can be achieved.

  ADVANTAGE OF THE INVENTION According to this invention, efficient power saving operation can be performed in the network system corresponding to WOL which employ | adopted the starting method by Wake Up Frame.

1 is a diagram illustrating a configuration example of a printer including a network controller according to an embodiment. FIG. It is a figure which shows an example of the network system in which a GARP packet is used. It is a figure which shows an example of the data structure of a GARP packet. 6 is a flowchart illustrating an example of an operation performed by a printer including a network controller according to an embodiment. It is a figure which shows the structural example of the conventional information processing apparatus corresponding to WOL. It is a figure which shows an example of the data pattern of Magic Packet. It is a figure explaining the comparison with the data pattern and the preset data pattern which are performed when the starting method by Wake Up Frame is employ | adopted. It is a figure which shows an example of a network system in case the node which issues the instruction | indication of wakeup, and the node of the power saving state used as the object are partitioned off with a router. It is a figure which shows the example of communication when an ARP packet is broadcast. It is a figure which shows an example of an ARP table. It is a figure which shows an example of the ARP table hold | maintained in the memory of the router. It is a 1st figure which shows the example of communication in case node A1 makes a request of lpr and ftp with respect to node B2. It is a 2nd figure which shows the example of communication in case node A1 makes a request of lpr or ftp with respect to node B2. It is a figure which shows the example of communication when the entry of node B2 is not included in the ARP table by the side of the subnet B which a router hold | maintains.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram illustrating a configuration example of a printer (printing apparatus) including a network controller according to an embodiment of the present invention.

  In FIG. 1, a printer 1 is an example of an information processing apparatus compatible with WOL that employs a startup method using a Wake Up Frame, and includes a network controller 2, a power supply control unit 3, a data processing unit 4, an image generation unit 5, and paper. A conveyance control unit 6 is included.

  The network controller 2 is, for example, a NIC having a function for starting the printer 1 from a power saving state, and includes a packet transmitting / receiving unit 7, a packet generating / analyzing unit 8, a free running timer for GARP automatic transmission (hereinafter simply “timer”). 9) and a GARP transmission buffer (hereinafter simply referred to as "buffer") 10.

The packet transmission / reception unit 7 transmits / receives packets via a LAN (Ethernet (registered trademark)).
The packet generator / analyzer 8 generates a packet to be transmitted by the packet transmitter / receiver 7, analyzes a packet received by the packet transmitter / receiver 7, and the like. When the received packet is matched with a predetermined data pattern as a result of analyzing the received packet, a wake-up request (“Wake” for starting the printer 1 from the power saving state is set. Up request ") signal is transmitted to the power supply control unit 3. That is, since print data (print job) sent from the host computer (not shown) connected via the LAN to the printer 1 is sent in the format of the lpr protocol or the ftp protocol, there are various types of data on the LAN. Only when a specific data pattern of an lpr or ftp packet that transmits print data is identified from the packet, a wake-up request ("Wake Up request") signal for starting the printer 1 from the power saving state is sent to the network controller. 2 outputs to the power supply control unit 3 so that the printer 1 is switched from the sleep state to the operation state. Whether or not the data pattern of the received packet matches a predetermined specific data pattern indicating that the host computer is information that instructs the printer to perform print processing is shown in FIG. This is done as described above. The specific data pattern can be arbitrarily set by an administrator or the like. For example, a data pattern related to an lpr request such as the specific data pattern 112 shown in FIG. 7 or a data pattern related to an ftp request. Etc. It is also possible to set a plurality of specific data patterns as specific data patterns in order to identify all print instructions transmitted from the host device.

The timer 9 periodically outputs a trigger signal (trigger pulse) every time preset by an administrator or the like or every time preset as an initial setting.
The buffer 10 stores the GARP packet transmitted from the packet transmitting / receiving unit 7. The GARP packet is generated by, for example, a packet generation / analysis unit.

  In the network controller 2 having such a configuration, for example, the packet transmitting / receiving unit 7 is stored in the buffer 10 according to a trigger signal periodically output by the timer 9 when the printer 1 is in the power saving state. A GARP packet is periodically broadcast (broadcast transmission).

  The power control unit 3 performs power control of the printer 1 such as shifting the printer 1 from the activated state to the power saving state or returning the printer 1 from the power saving state to the activated state. For example, when the power control unit 3 receives a power saving request signal from a control unit (not shown) of the printer 1, the power control unit 3 performs power control for shifting the printer 1 from the activated state to the power saving state. The power saving request signal is, for example, a signal that is output when the printer 1 has not been operated or processed for a certain period of time. Further, for example, when receiving a wake-up request signal from the packet generation / analysis unit 8, the power control unit 3 performs power control for returning the printer 1 from the power saving state to the activated state. When the power supply control unit 3 performs power supply control for shifting the printer 1 from the activated state to the power saving state, the printer 1 is in a state where power is supplied only to the minimum necessary unit including the network controller 2 (energized state). ), And no power is supplied to other units (non-energized state). On the other hand, when the power supply control unit 3 performs power supply control for returning the printer 1 from the power saving state to the startup state, the unit that has been turned off in the power saving state is turned on in the printer 1.

  The data processing unit 4 performs various processes. For example, when the packet generation / analysis unit 8 analyzes the packet received by the packet transmission / reception unit 7 and it is a packet related to the lpr request, the data processing unit 4 performs processing on the data included in the packet. Processing necessary for printing is performed, and the processed data is output to the image generation unit 5. Such processing is performed, for example, while synchronizing with the image generation unit 5. The processing result is notified to the packet generation / analysis unit 8, for example. Then, a packet related to the notification is generated by the packet generation / analysis unit 8, and the generated packet is transmitted by the packet transmission / reception unit 7 to the transmission source of the lpr request.

The image generation unit 5 performs processing for generating an image on a sheet based on the processed data output by the data processing unit 4.
The paper conveyance control unit 6 performs control related to the conveyance of the paper on which image generation is performed by the image generation unit 5. For example, the paper transport control unit 6 controls a motor for transporting paper.

  With such a configuration, the printer 1 including the network controller 7 has a function of periodically broadcasting GARP packets when in the power saving state.

Here, the GARP packet will be described.
The GARP packet is a packet used in a network system including a redundant routing system, for example.

  FIG. 2 is a diagram illustrating an example of a network system in which a GARP packet is used. Note that the IP addresses and MAC addresses of the nodes A1, A2, B1, and B2 shown in FIG. 2 are the same as those of the nodes A1, A2, B1, and B2 shown in FIG.

  In the network system 21 shown in FIG. 2, the network is divided into two subnets A and B by two routers A and B. Nodes A1 and A2 and routers A and B are connected to the subnet A, and nodes B1 and B2 and routers A and B are connected to the subnet B. However, in the two routers A and B, normally, only the router A is active and the router B is inactive. In other words, normally, only router A is used and router B is not used. Router B becomes active immediately only when a failure (trouble) occurs in router A, and functions as an alternative router for router A. The routers A and B communicate with each other to notify each other. For example, when a failure occurs in the router A, the router B is notified immediately. With such a mechanism, the adverse effect of the failure of the router A on the network system 21 is minimized.

  In the network system 21, as described above, when a failure occurs in the router A, the router B becomes an alternative router for the router A, and therefore the IP addresses of both routers are the same. However, since the MAC address is defined as unique for each device, the MAC addresses of both routers are different.

For this reason, the following problem arises as it is.
In the network system 21, normally, the ARP table of each node includes an entry of the IP address and MAC address of the router A for communication with another subnet. For example, the ARP table of the node A1 includes an entry for the IP address and MAC address of the router A for communication with the subnet B. At this time, the router B is deactivated because the IP address is duplicated.

  Here, assuming that a failure occurs in the router A and the router B functions as an alternative router, the output destination of the packet when each node communicates with another subnet is the router A according to its own ARP table. Because of the MAC address, communication cannot be performed.

  Therefore, when the router B functions as an alternative router, first, the GARP packet is broadcast in the subnet A and the subnet B. Then, each node that has received the GARP packet rewrites the MAC address in the entry of router A included in its own ARP table to the MAC address of router B based on the received GARP packet. As a result, the output destination of the packet when each node communicates with another subnet is the MAC address of router B, which is an alternative router, according to its own ARP table. Therefore, communication can be performed via router B. it can.

  Here, an example in which the router B broadcasts the GARP packet is shown, but even when each node broadcasts the GARP packet, the same processing is performed in each node or router that has received the GARP packet. For example, in the network system 21, when the node B2 broadcasts the GARP packet, the node B1 that has received the GARP packet or the active router has received the MAC address in the entry of the node B2 included in its own ARP table. Rewrite to the MAC address of Node B 2 based on the GARP packet. However, in this case, if there is no change in the device of the node B2, the MAC address before rewriting and the MAC address after rewriting are the same.

  FIG. 3 is a diagram illustrating an example of the data structure of the GARP packet. Note that the GARP packet shown in FIG. 3 is also an example of the GARP packet broadcast from the node B2 shown in FIG.

  As shown in FIG. 3, the GARP packet includes an Ethernet (registered trademark) header part and an ARP request part. The Ethernet (registered trademark) header part includes a destination MAC address and a source MAC address. The ARP request unit includes a transmission source MAC address, a transmission source IP address, a destination MAC address, and a destination IP address. Here, the destination MAC address of the Ethernet (registered trademark) header is “FF-FF-FF-FF-FF-FF” indicating a broadcast address. The destination MAC address of the ARP request unit is “00-00-00-00-00-00” indicating an unknown destination address. The source MAC address of the Ethernet (registered trademark) header part and the source MAC address of the ARP request part are the MAC address of the device that transmits the GARP packet (in this example, the MAC address “Node B2 MAC address“ 00-22-64-b9-31-c4 "). The source IP address and the destination IP address of the ARP request unit are the IP addresses of the devices that transmit the GARP packets (in this example, the IP address “192.168.2.2” of the node B2 shown in FIG. 2). That is, the destination IP address is the same as the source IP address.

The printer 1 including the network controller 2 according to the present embodiment performs the following operation using such a GARP packet.
FIG. 4 is a flowchart illustrating an example of an operation performed by the printer 1 including the network controller 2 according to the present embodiment.

  In this example, it is assumed that the printer 1 is the node B2 in the network system 121 shown in FIGS. Further, it is assumed that the network system 121 is compatible with WOL that employs a startup method using a Wake Up Frame. Also, all nodes and routers included in the network system 121, like standard devices, have entries that are not used for 2 minutes (refresh interval) in the ARP table held by itself. Processing shall be performed so as to delete it.

  As shown in FIG. 4, when the power of the printer 1 is turned on and power is supplied to each unit of the printer 1 so that the printer 1 is activated, first, the packet generation / analysis unit 8 generates a GARP packet, Is stored in the buffer 10 (S1). The GARP packet stored here is, for example, the GARP packet shown in FIG.

  Next, the timer 9 is set to periodically output a trigger signal every minute, for example, according to a setting by an administrator or the like or according to an initial setting (S2). Here, as described above, the time of 1 minute is set in consideration that processing is performed so that entries that are not used for 2 minutes are deleted from the ARP table in all nodes and routers included in the network system 121. This is an example of a time shorter than the two minutes.

  Next, it is determined whether or not the power control unit 3 has received a power saving request signal from, for example, a control unit (not shown) of the printer 1 (S3). The determination is repeated. On the other hand, if the determination result in S3 is Yes, the power supply control unit 3 performs power supply control for causing the printer 1 to transition (shift) from the activated state to the power saving state (S4). As a result, the printer 1 enters a power saving state in which power is supplied only to the minimum necessary units including the network controller 2 and power is not supplied to other units. In S4, the timer 9 starts to output a trigger signal periodically every minute according to the setting made in S2.

  Next, it is determined whether the packet transmitting / receiving unit 7 has received a packet having a data pattern that matches a specific data pattern preset in the packet generating / analyzing unit 8 (S5). Specifically, when the packet transmission / reception unit 7 receives a packet, the packet generation / analysis unit 8 analyzes the packet, and whether or not the data pattern of the received packet matches a specific data pattern set in advance. Determine whether. This determination is performed, for example, as described with reference to FIG.

  In the determination of S5, when the determination result is Yes, the packet generation / analysis unit 8 outputs a wake-up request signal to the power supply control unit 8, and the power supply control unit 8 that receives the signal generates power saving for the printer 1. Power supply control is performed to transition (transition) from the state to the activated state (S6). As a result, in the printer 1, the unit that is not supplied with power in the power saving state is in a state in which power is supplied and is activated. After S6, the process returns to S3.

  On the other hand, if the determination result in S5 is No, it is determined whether or not one minute has passed according to the presence or absence of a trigger signal periodically output from the timer 9 every one minute (S7). Specifically, when there is a trigger signal, it is determined that one minute has elapsed, and when there is no trigger signal, it is determined that one minute has not elapsed. If the determination result in S7 is No, the process returns to S5. On the other hand, when the determination result in S7 is Yes, the packet transmitting / receiving unit 7 broadcasts the GARP packet stored in the buffer 10 (S8). Then, after S8, the process returns to S5.

  With this operation, when the printer 1 is in the power saving state, a GARP packet is broadcast from the printer 1 every minute. Accordingly, in each of the nodes B1, B3, B4 and the router 122 that can receive the GARP packet from the printer 1, the ARP table held by itself when the printer 1 receives the GARP packet for the first time after the printer 1 enters the power saving state. If the printer 1 entry is included, the printer 1 entry included in the ARP table is updated each time a GARP packet is received from the printer 1 while the printer 1 is in the power saving state. It will not be deleted. In this way, while the printer 1 is in the power saving state, if the entry of the printer 1 continues to be included in the ARP table 132 on the subnet B side held by the router 122, for example, a node belonging to the subnet A (for example, a node) The packet addressed to the printer 1 transmitted from A 1) is relayed to the printer 1 by the router 122 according to the ARP table 132. Therefore, in such a case, for example, as described with reference to FIG. 14, there is no problem that the communication fails because there is no entry of the printer 1 in the ARP table 132 of the router 122. As described with reference to, it is possible to set to wake up only for lpr and ftp requests. Of course, in such a case, the setting of waking up for the ARP request becomes unnecessary, so that the printer 1 does not need to wake up excessively.

  As described above, according to the printer 1 including the network controller 2 according to the present embodiment, since the GARP packet is periodically transmitted to prevent the ARP table from being refreshed and cleared, nodes and routers belonging to the same subnet The entry of the printer 1 can be prevented from being deleted from the ARP table, and the ARP request is not required at the time of communication addressed to the printer 1, so that the protocol of the packet that is a condition for wakeup from the power saving state can be set. Detailed setting is possible only for the print instruction information, and the sleep release control can be performed only when a print instruction is sent from the host computer to the printer. Therefore, efficient power-saving operation can be performed in a network system compatible with WOL that employs a startup method using Wake Up Frame.

  In the present embodiment, the printer 2 is employed as an example of the information processing apparatus including the network controller 2, but an information processing apparatus other than the printer 2 can be employed.

  In the description of FIG. 4, all the nodes included in the network system 121 include the network controller 2 and, like the printer 1, start up from the power saving state when receiving a packet having a specific data pattern. It is also possible to configure as described above.

  In the description of FIG. 4, the timer 9 is set to periodically output a trigger signal every one minute, but the trigger signal is periodically generated every time shorter than two minutes excluding one minute. Of course, it is also possible to set to output.

In the description of FIG. 4, all nodes and routers included in the network system 121 perform processing to delete an entry that is not used for 2 minutes in the ARP table held by itself. However, for example, when there is an entry that has not been used for a predetermined time other than 2 minutes, it may be configured to perform processing so as to delete it. However, in this case, the timer 9 is set so that the trigger signal is periodically output every time shorter than the predetermined time.
Furthermore, in the above embodiment, the method of transmitting the GARP packet as dummy communication so that the information entered in the ARP table does not disappear because there is no communication for a predetermined period has been described. In addition to preventing the entry information from being cleared, it is selected as the most suitable technique of the present invention, particularly in the sense that it does not cause a significant change in the other line environment, but keeps the entry in the ARP table. As long as the communication information does not have a great influence on other line environments, the other information may be transmitted on the network.

  Although several embodiments of the present invention have been described, the present invention is included in the inventions described in the claims and their equivalents. Hereinafter, the invention described in the scope of claims at the beginning of the filing of the present patent application will be added.

Appendix 1
A network controller provided in the information processing apparatus,
A unit data transceiver for transmitting and receiving unit data;
When the data pattern of the unit data received by the unit data transmitting / receiving unit matches a specific data pattern set in advance, a wakeup request signal for starting the information processing apparatus from the power saving state is output. A unit data analysis unit
With
The unit data transmission / reception unit transmits, at a predetermined time, information for preventing entry information of an address resolution protocol table interposed on the network from being refreshed and cleared when the information processing apparatus is in a power saving state.
A network controller characterized by that.

Appendix 2
A timer unit that periodically outputs a trigger signal;
The network according to claim 1, wherein the unit data transmitting / receiving unit broadcasts a GARP packet at a predetermined time according to a trigger signal output from the timer unit when the information processing apparatus is in a power saving state. controller.

Appendix 3
The network controller according to appendix 1 or 2, further comprising a storage unit for storing the GARP packet.

Appendix 4
4. The network controller according to claim 1, wherein the information processing apparatus is a printing apparatus.

Appendix 5
The network controller according to any one of appendices 1 to 4, wherein the specific data is information instructing printing sent from a host device.

Appendix 6
A wakeup control method for activating an information processing apparatus from a power saving state,
The network controller provided in the information processing apparatus is:
A process of transmitting information for preventing entry information of an address resolution protocol table interposed on the network from being refreshed and cleared at a predetermined time when the information processing apparatus is in a power saving state;
When unit data is received, if the data pattern of the unit data matches a specific data pattern set in advance, a wake-up request signal for starting the information processing apparatus from the power saving state is output. Processing to
Wake-up control method characterized by performing.

DESCRIPTION OF SYMBOLS 1 ... Printer 2 ... Network controller 3 ... Power supply control part 4 ... Data processing part 5 ... Image generation part 6 ... Paper conveyance control part 7 ... Packet transmission / reception part 8 ... -Packet generation / analysis unit 9-GARP automatic transmission free running timer 10-GARP transmission buffer 21-Network system 101-Information processing device 102-Network controller 103-Power supply control unit 104-Processing unit 105-Packet Transmission / reception unit 106, packet generation / analysis unit 111, TCP / IP packet 112, specific data pattern 121, network system 122, router 131, ARP table 132 on the subnet A side, ARP table on the subnet B side

Claims (6)

A network controller provided in the information processing apparatus,
A unit data transceiver for transmitting and receiving unit data;
When the data pattern of the unit data received by the unit data transmitting / receiving unit matches a specific data pattern set in advance, a wakeup request signal for starting the information processing apparatus from the power saving state is output. A unit data analysis unit
With
The unit data transmission / reception unit transmits, at a predetermined time, information for preventing entry information of an address resolution protocol table interposed on the network from being refreshed and cleared when the information processing apparatus is in a power saving state.
A network controller characterized by that. A timer unit that periodically outputs a trigger signal;
The unit data transmitting / receiving unit periodically broadcast-transmits information for preventing the refresh clear according to a trigger signal output from the timer unit when the information processing apparatus is in a power saving state. The network controller according to Item 1.   The network controller according to claim 1, further comprising a storage unit that stores a GARP packet as information for preventing the refresh clear.   The network controller according to claim 1, wherein the information processing apparatus is a printing apparatus.   The network controller according to claim 1, wherein the specific data is information instructing printing sent from a host device. A wakeup control method for activating an information processing apparatus from a power saving state,
The network controller provided in the information processing apparatus is:
Processing for transmitting information to prevent the entry information of the address resolution protocol table intervening on the network from being refreshed and cleared when the information processing apparatus is in a power saving state on the network at a predetermined time;
When unit data is received, if the data pattern of the unit data matches a specific data pattern set in advance, a wake-up request signal for starting the information processing apparatus from the power saving state is output. Processing to
Wake-up control method characterized by performing.

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