JP2001268095A - Network device, parameter setting method for the network device and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To relieve a load of network traffic by the DHCP protocol by storing an IP address acquired from a network server and using it continuously. SOLUTION: A DHCP packet is interpreted and the DHCP packet is configured on the basis of the interpretation. Data transmission reception is made with the network server on the basis of the configured DHCP packet and a validity of data received from the network server is discriminated (S1201). When the validity is infinite (S120-Yes), the data are stored in a memory (S1202-Yes, S1205), and a parameter for reconnection is set on the basis of the stored data in the case of the reconnection to the network.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a network device connected to a network, a parameter setting method for the device, and a storage medium storing a program for executing the method on a computer.

[0002]

2. Description of the Related Art In recent years, a local network (LAN) in which computers are interconnected has become widespread, and such a LAN can be built on a building floor, the whole building, an area, or a larger area. Such networks are further interconnected and can be connected to global networks. Each such interconnected LAN may have a variety of hardware interconnect technologies and a number of network protocols.

In such a LAN, TCP / IP is a typical network protocol.

[0004] TCP / IP is a group of hierarchical network protocols.
tocol) and ICMP (Internet Control Message Protoc)
ol), ARP (Address Resolusion Protocol), etc.
TCP (Transmission Control Pro)
tocol) and UDP (User Datagram Protocol).
(For details of each protocol and IP address system,
"Detailed Explanation TCP.IP" W. Richard Stevens = Author / Naoji Inoue = Translation, Yasuo Tachibana = Translation Softbank Corp. 1997
See the first edition issued March 31, 2012. When performing network communication using the TCP / IP protocol, it is necessary to uniquely determine a logical address on the network called an IP address. IP address is 32 bits (4 bytes)
, And is generally divided into 8 bits.
50.61.146.100 (0x963d9264)
Notation as follows.

[0005] In order to set such an IP address in a network device, a network device device requires:
Various attempts have been made. Generally, in the case of a computer terminal connected to a network, it is possible to set an IP address in the computer by inputting from a keyboard. In the case of a network terminal that does not have a keyboard, or when it is desired to manage IP addresses collectively, a DHCP (Dynamic Host Configuration) is generally used.
Protocol), BOOTP, and RARP, a method has been used in which a network device acquires an IP address from a server on a network when the power is turned on and sets the IP address.

[0006] Among them, recently, DHCP has been more commonly used and spread.

[0007] DHCP is a protocol defined by RFC2131 and is an extension of the BOOTP protocol.

In general, a network device serving as a DHCP client is turned on after the power is turned on.
Send er packet to detect server. If there is a DHCP server on the network,
The HCP Discover response packet is returned.

[0009] The network device sends a request packet requesting an IP address to the server that has returned. In response to the request, the server lends an unused IP address from the group of IP addresses managed by the server to the network device with a time limit.
The network device operates using the IP address with the expiration date (lease time). When the expiration date is approaching, the server is again notified
A request packet requesting the extension of the specification of the P address is transmitted. If OK, the server will lend its IP address with a new expiration date. If the client network device does not send a Request packet even after the expiration date due to power-off or the like, the IP address used by the client is determined to be usable again, and an unspecified IP address Is registered in the server.

Each time the power is turned on, the network device, which is a client, inquires of the server about the IP address, and obtains the IP address by performing the above procedure. It is an outline of a solution. In addition, the expiration date of the IP address at this time also starts from
Changes can be made indefinitely.

[0011]

However, in the above conventional example, if the power of the network device is cut off even if the expiration date of the IP address is set to be indefinite in the server setting, the network device is started up next. Sometimes, there is a problem that it is necessary to access the server again to obtain an IP address. That is, D
In the communication by the HCP, since a large number of broadcast packets are generated, a load is imposed on the traffic.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and when performing IP address resolution by DHCP, if the expiration date of the IP address is specified indefinitely, the IP address is designated. A network device that stores the IP address provided and starts up with the previously given and stored IP address without using the DHCP protocol when the power is shut off, a parameter setting method for the network device, and It is an object of the present invention to provide a storage medium storing a program code for executing the method on a computer.

In order to solve the above problems and achieve the object, a network device and a method thereof according to the present invention are mainly characterized by the following configuration.

That is, the network device is a DHC
Interpreting means for interpreting the P packet, means for configuring a DHCP packet based on the interpretation of the interpreting means, transmitting and receiving means for transmitting and receiving data to and from a network server based on the configured DHCP packet, By sending / receiving means, a judging means for judging the expiration date of the data received from the network server, and by the judging means, when the expiration date of the data is indefinite,
Storage means for storing the data, and setting means for setting parameters for reconnection based on the data stored by the storage means when reconnecting to a network,
It is characterized by having.

[0015] Also, the method for setting parameters of a network device includes an interpreting step of interpreting a DHCP packet;
A step of forming a DHCP packet based on the interpretation of the interpreting means, a step of transmitting / receiving data to / from a network server based on the configured DHCP packet, and a step of receiving / receiving data from the network server by the step of transmitting / receiving. A judging step of judging the expiration date of the data obtained, and, if the expiration date of the data is indefinite, a storing step of storing the data,
And setting a parameter for reconnection based on the stored data when reconnecting to the network.

Also, the present invention is a storage medium storing a program code for executing a parameter setting method of a network device by a computer, wherein the program code includes a code of an interpretation step for interpreting a DHCP packet and an interpretation of the interpretation means. A code of a step of configuring a DHCP packet, a code of a transmission / reception step of transmitting / receiving data to / from a network server based on the configured DHCP packet, and a code of the transmission / reception step. A code of a determining step of determining the expiration date of the received data, and, if the expiration date of the data is indefinite, by the determining step, a code of a step of storing the data; At this time, based on the stored data, And code setting step of setting the data,
It is characterized by having.

[0017]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a schematic diagram showing a configuration in which a network board is connected to a printer as the network device of the present embodiment.

Reference numeral 101 denotes a network board, which is a network device connected to the local area network (LAN) 100.

Connection to LAN is 10B with RF-45
They are connected via an interface such as case-T. The personal computer (PC) 103 is also L
PC 103 is connected to LAN 10
0 can communicate with the network board 101. In the PC 103, a DHCP server program is operating, and manages an IP address. In response to a DHCP request packet from the network device 101 or the like, the PC 103 returns a DHCP response packet.

Typically, a LAN network such as LAN 100 provides services to a somewhat local group, such as a user group on one floor in a building or on multiple consecutive floors. For example, when the user is in another building, a wide area network (WAN) may be used according to the distance between the users. A WAN is basically an aggregation formed by connecting several LANs with a high-speed digital line such as an integrated high-speed service digital network (ISDN) telephone.

FIG. 2 is a block diagram showing an outline of the internal configuration of the network board 101 in the present embodiment.

The network board 101 is a CPU 20
1, a ROM 202, a RAM 203, and an extended I / F control unit 20 storing the program of the present embodiment
4. NVRAM 20 for storing various setting parameters
5. Network I / F control unit 206 for communicating with the network, timer 207, bus 20 to which these are connected
Consists of eight.

The network board 101 is connected to the printer 102 via the extension I / F control unit 204. Any device that can be controlled by the extended I / F control unit 204 can be connected not only to a printer but also to a facsimile, a copier (registered trademark), or the like, and can connect various devices to a network. .

FIG. 3 is a schematic diagram showing a program configuration of the network board 101 in the present embodiment.

Reference numeral 301 denotes a printer I / F driver module which controls the extended I / F control unit 204 to transmit and receive data to and from the printer. A print protocol module 302 supports a general-purpose print protocol on a network. Reference numeral 303 denotes a network protocol communication module which controls network communication. 304, a network driver module;
Is a routine for transmitting and receiving packets on the network.

The print protocol module 302 receives print data from the network using the network protocol communication module 303 according to a print communication procedure determined by the protocol. The received print data is sent to the network device 102 such as a printer via the printer I / F driver module 301.

Reference numeral 305 denotes an I mounted according to the present invention.
In the P address resolution module, when the power of the network board is turned on, the TC
PIP setting parameters (IP address of this board,
Subnet mask, gateway address) are set in the network protocol communication module.

FIG. 4 is a program configuration diagram of the TCP / IP protocol in the network protocol communication module 303 in this embodiment.

Reference numeral 401 denotes a socket interface management module, which includes a print protocol module 302 and an IP
The address resolution module 305 provides an interface called a socket. By using this interface, the print protocol module (30
2) The IP address resolution module (305)
Communication can be easily performed using the CP / IP protocol. 402 is a TCP management module, and 403 is a UDP management module. The TCP management module 402
UDP management module 403 with CP protocol implemented
Implements the UDP protocol. The TCP management module and the UDP management module use the IP module 406 to perform communication. Reference numeral 404 denotes an ICMP management module on which an ICMP protocol is mounted. 40
Reference numeral 6 denotes an IP module on which an IP protocol is mounted. Reference numeral 407 denotes an ARP module on which the ARP protocol is mounted.

FIG. 5 is a conceptual diagram showing an outline of a DHCP message frame.

Reference numeral 501 denotes Ethernet (registered trademark).
Next, Header, IP Header 502, and UDP
Following the header 503 and the BOOTP / DHCP 504, a CRC 505 is added to the end of the frame.

FIG. 6 shows the Ethernet Heade in this embodiment.
It is a figure showing the schematic structure of r501.

In this embodiment, the TCP / IP protocol is
Sending and receiving in EthernetII format. This drawing
In the schematic diagram of the Ethernet II format, 601 indicates a destination address, 602 indicates a source address, and 603 indicates a frame type. Destination address 601, source address 6
02 stores a MAC address unique to the device. Here, the MAC address is a physical address unique to the network. In the case of Ethernet, the first 3
Bytes are used as IEEE (Institute of Institute)
Electrical and Electronic Enginerrs, the Institute of Electrical and Electronics Engineers). The remaining three bytes are codes managed by each vendor independently (to avoid duplication). As a result, there is no network device having the same physical address in the world, and different addresses are all assigned.

The frame type 603 is determined to be 0x0800 for IP and 0x0806 for ARP.

FIG. 7 is a diagram showing a schematic configuration of the IP header.

701 is the IP version, 702 is the IP version
The header length 703 is a service type (Type Of).
Service: TOS), 704 is the total data length, 705 is an identifier, 706 is a flag field, 707 is a lifetime field, 708 is a protocol identification, 709 is an IP header checksum, 710 is a source IP address, 7
11 is a destination IP address.

FIG. 8 is a diagram showing a schematic configuration of a UDP header.

801 is a source port number, 802 is a destination port number, 803 is a UDP data length, 804
Is a UDP checksum.

FIG. 9 is a diagram showing a schematic configuration of DHCP (BOOTP). Reference numeral 901 denotes an opcode, an identifier for determining a request or response, and reference numeral 902 denotes a hardware type. In this embodiment, 1 is used. Reference numeral 903 denotes a hardware length length. In this embodiment, 6, 904 is a hop count, 914 is a transaction ID, 905.
Is the number of seconds, 906 is the client IP address, and 907 is the user IP address, given by the server.
908 is the server IP address, 909 is the gateway I
The P address, 910 stores the client hardware address, and 911 stores the server host name. In 912, a startup file name is stored. 913 stores vendor specification information.

FIG. 10 shows the vendor specification information 9 in FIG.
13 is a detailed diagram.

Various information can be stored in the vendor specification information. In the case of DHCP, first, 4-byte data (99.130.83.99) called Magic Cookie is stored in the first 4 bytes. The subsequent data are stored one after another in the order of code (Code), length (Len), and type (Type).

[0042] DHCP Message Type (1
002) indicates a request or response to the DHCP message, and its code is 53 bytes, and the length is 1 byte.
One of the following is stored in te and type.

(1) DHCP DISCOVER (2) DHCP OFFER (3) DHCP REQUEST (4) DECP DECLINE (5) DHCP ACK (6) DHCP NACK (7) DHCP RELEASE Client ID (1003) is an ID for identifying a client. In the present embodiment, the code is 61 bytes, the length is 2 bytes, and the type is 0001.

The ServerID (1004) is a server ID uniquely determined by the server. The code stores 54 bytes, the length is 4 bytes, and the type stores a 4-byte ID.

RequestList (1005) indicates a list of information required by the client, and its code is 5
5 bytes, length is 3 bytes, and the type stores a code of necessary information.

In the present embodiment, the data required by the client includes the subnet mask (1006) and the gateway (1006).
7), Vender Specification (1008).

SubnetMask (1006) is a subnet mask value which is one of the setting parameters of the board. The code is 1 byte, the length is 4 bytes, and the type stores the subnet mask value.

Gateway (1007) is a gateway address which is one of the setting parameters of the board. The code is 3 bytes, the length is 4 bytes, and the type stores the gateway address.

The Vender Specification (1008) is vendor-specific information. Its code is 43 bytes, its length is 1 byte, and its type stores a set value.

In this embodiment, the board determines whether or not to resolve the IP address using the DHCP protocol every time the power is turned on in accordance with the set value.

LeaseTime is the expiration date of the IP address.
The code stores 51 bytes, the length stores 4 bytes, and the type stores the expiration date.

FIGS. 11 and 12 show the present embodiment.
It is a flowchart of a process of a module.

Hereinafter, the operation of each module and the flow of the processing will be described for the outline of the processing of the DHCP packet.

<Transmission processing> The DHCP request packet created by the IP address resolution module (305) is sent to the network protocol communication module (303).
Socket interface management module (401)
To the UDP management module (403). In the UDP management module (403), the source port number 801 (FIG. 8) indicates "68" indicating that the client is a client, and the destination port number 802 (FIG. 8) indicates "67" indicating that the client is for a server. Store. U
The DP management module (403) has a UDP length of 8
After calculating the checksum by setting 03, 804
The data is stored in the area indicated by. The created packet is sent to the IP module (406).

The IP module (406) sets the parameters of the IP header shown in FIG. 7 in addition to the transmission packet created by the UDP management module. In the DHCP protocol, when a client transmits a packet, a source IP address 71
0 (FIG. 7), 0.0.0.0, and 255.255.255.2 as the destination IP address 711 (FIG. 7).
Set 55. The created packet is sent to the network driver module (304).

The network driver module (30)
4) sets the parameters of the Ethernet header shown in FIG. 6 in addition to the transmission packet created by the IP module (406). Since the protocol type is a transmission request from the IP module (406),
0x0800 indicating P is set. DHC
In the P protocol, its own MAC address is set as the source address 602, and the destination address (601)
Is set to 0xffffffffffffff.

The DHCP packet created in this way is transmitted on the network via the network I / F control unit (206). At this time, the CRC code (50
5) is added to the end of the packet.

<Reception Processing> The network driver module (304) receives the Ethernet (registered trademark) frame shown in FIG. 5 via the network I / F control unit (206). The network driver module (304) includes an Ethernet header part of the frame (FIG. 6).
Is analyzed, and it is determined whether or not it is for its own MAC address. Frames not intended for the own MAC address or frames in which the CRC (505) has caused an error are discarded at this point. If the destination address is a broadcast address or a registered multicast address even if the destination address is not for its own MAC address, the frame is fetched.

Next, the network driver module (3)
04) determines the type (603) of the received frame. If this is 0x0800, the subsequent byte stream is determined to be an IP packet, and the packet is delivered to the IP module (406) in the network protocol communication module (303). In the case of 0x0806, it is determined that the packet is an ARP packet, and the ARP module (40
7) Deliver the packet.

The IP module (406) analyzes the IP header shown in FIG. In the packet received from the network driver module (304), it is determined whether the destination IP address is its own IP address. Any packet that is not its own IP address or that does not have the correct checksum is discarded at this point. Even if it is not its own IP address, if the destination IP address is a broadcast address or a registered multicast address, it processes the packet.

Next, the IP module (406) judges the identification of the protocol (708). Protocol identification (7
08) indicates TCP, the packet is
Deliver to the management module (402). In the case of UDP, it is delivered to the UDP management module (403), and in the case of ICMP, it is delivered to the ICMP management module (404).

Upon receiving the packet from the IP module (406), the UDP management module (403) analyzes the UDP header shown in FIG. The UDP management module 403) checks the checksum (804), and discards this packet if this is an invalid value.

Thereafter, the UDP management module (403)
Determines the UDP port number (802) and sends the packet whose destination port number (802) is “68” to the IP through the socket interface management module (401).
The address is passed to the address resolution module (405).

The IP address resolution module (305) analyzes and processes the DHCP packet shown in FIGS.

Hereinafter, the flow of processing of the IP address resolution module (305) of this embodiment will be described with reference to a flowchart.

When the power is turned on and the IP address resolution module (305) starts up, first, the IP address resolution module (305)
The P address resolution mode is read (S110
1). When the IP address resolution mode is not the DHCP mode (S1102-No), the IP address resolution module (305) further reads each setting parameter from the NVRAM (205) (S1103). Then, TCPIP is set using these setting parameters (IP address, subnet mask, gateway address), and normal communication is enabled (S1104).

If the IP address resolution mode is the DHCP mode (S1102-Yes), the D address shown in FIG.
Make various settings for HCP parameters. Opcode (90
After storing the request code in 1) and setting each parameter, DHCP M is used as the vendor specification information (913).
The message type is changed to "DHCP DISCOVE
R ", and a ClientID is set to form a packet. The packet is transmitted to the network via the socket interface management module (401) according to the procedure described above (S1105).

The IP address resolution module (30) waits until a response is returned from the DHCP server.
5) waits for the response (S1106).

When a response is returned from the DHCP server, each setting is again performed on the DHCP parameters shown in FIG. After storing the request code in the opcode (901) and setting each parameter, D
DHCP REQ for HCP Message Type
Set with UEST, ClientID, Request
Set List and Server returned from server
An ID is set to compose a packet. The packet is sent through the socket interface management module 401,
It is transmitted to the network according to the procedure described above (S11
07).

In response to this request, each set parameter is obtained.

The IP address resolution module (305) waits until the response is returned (S1108). When a response is returned from the server, the IP address resolution module determines the lease time in the vendor specification information (913).
Is confirmed (S1201 in FIG. 12). LeaseTim
When e is 0xFFFFFFFF, it indicates an indefinite expiration date. In the case of 0xFFFFFFFF, the content Vende of the vendor specification information (913) is next.
Confirm rSpec (S1202).

When the set value is 0x01, the set parameter is stored in the NVRAM (205) (S120).
3).

In the setting parameter, the IP address is (90
From the user IP address of 7), the subnet mask is the SabunetMask of the vendor specification information (913).
From the gateway address, the vendor specification information (91
Read each from Gateway of 3).

With these settings, TCPIP is set (S1204), and the IP address resolution mode is set to DHCP.
It is set to not be used and stored in the NVRAM (205) (S1205).

Thus, at the next power-on, N
TC with setting parameters stored in VRAM (205)
The PIP will be set and it will operate.

When the lease time is 0xFFFFFFFF
If it is not F, or if VendorSpec is not 0x01, after setting TCPIP with the setting parameters read from the packet (S1206), the lease timer is set to the timer 207, and the normal operation of DHCP is started.

[0077]

[Other Embodiments] Even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), an apparatus (for example, a copying machine) Machine, facsimile machine, etc.).

Further, an object of the present invention is to supply a storage medium (or a recording medium) in which a program code of software for realizing the functions of the above-described embodiments is recorded to a system or an apparatus, and a computer (a computer) of the system or the apparatus. It is needless to say that the present invention can also be achieved by a CPU or an MPU) reading and executing the program code stored in the storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. Also,
When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also the operating system (OS) running on the computer based on the instructions of the program code.
It goes without saying that a case where the functions of the above-described embodiments are implemented by performing some or all of the actual processing, and the processing performs the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written in a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the program code is read based on the instruction of the program code. Needless to say, the CPU included in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the above-described flowcharts (shown in FIG. 11 and / or FIG. 12).

[0081]

As described above, according to the present invention,
If the expiration date of the IP address is specified indefinitely, the specified IP address is stored. If the power is cut off, the IP address previously given and stored without using the DHCP protocol is used. It is possible to start up, and it is possible to reduce the load on traffic without inquiring the server every time the power is turned on.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration in which a network board according to an embodiment is connected to a printer.

FIG. 2 illustrates a network board 101 according to the embodiment.
FIG. 2 is a block diagram schematically illustrating an internal configuration of the ASIC.

FIG. 3 is a diagram showing a network board 101 according to the embodiment;
FIG. 2 is a schematic diagram showing a program configuration of FIG.

FIG. 4 is a program configuration diagram of a TCP / IP protocol in a network protocol communication module according to the embodiment.

FIG. 5 is a conceptual diagram illustrating a frame outline of a DHCP message.

FIG. 6 is a schematic diagram of an Ethernet Header in the present embodiment.

FIG. 7 is a schematic diagram of an IP header.

FIG. 8 is a schematic diagram of a UDP header.

FIG. 9 is a schematic diagram of a DHCP packet.

FIG. 10 is a schematic diagram of vendor specification information.

FIG. 11 is a flowchart of processing of an IP address resolution module.

FIG. 12 is a flowchart of processing of an IP address resolution module.

Claims (9)

[Claims] 1. An interpreting means for interpreting a DHCP packet, means for constructing a DHCP packet based on the interpretation of the interpreting means, and data transmission / reception with a network server based on the configured DHCP packet Sending / receiving means; determining means for determining the expiration date of the data received from the network server by the transmitting / receiving means; storing the data when the expiration date of the data is indefinite by the determining means. A network device, comprising: storage means; and setting means for setting a parameter for reconnection based on data stored by the storage means when reconnecting to a network. 2. The network device according to claim 1, wherein the data includes an IP address, a subnet mask, and a gateway address. 3. An interpreting step of interpreting a DHCP packet; a step of forming a DHCP packet based on the interpretation of the interpreting means; and transmitting and receiving data to and from a network server based on the configured DHCP packet. A transmitting / receiving step; a judging step of judging an expiration date of the data received from the network server in the transmitting / receiving step; and storing the data if the judging step shows that the expiration date of the data is indefinite. A parameter setting method for a network device, comprising: a storage step; and a setting step of setting a parameter for reconnection based on the stored data when reconnecting to a network. 4. The method according to claim 3, wherein the data includes an IP address, a subnet mask, and a gateway address. 5. A storage medium storing a program code for executing a parameter setting method of a network device by a computer, the program code comprising: a code of an interpretation step for interpreting a DHCP packet; and an interpretation of the interpretation means. A code of a step of configuring a DHCP packet, a code of a transmission / reception step of transmitting / receiving data to / from a network server based on the configured DHCP packet, and a code of the transmission / reception step. A code of a determining step of determining the expiration date of the received data; and, if the expiration date of the data is indefinite, the code of a step of storing the data is determined by the determining step. At this time, based on the stored data, And a setting process code for setting the data. 6. The storage medium according to claim 5, wherein the data includes an IP address, a subnet mask, and a gateway address. 7. The network device according to claim 1, wherein the setting unit sets a parameter for connecting to a network based on data stored in the storage unit when the power is turned on. 8. The network device according to claim 1, wherein said storage means is a nonvolatile memory. 9. The network device according to claim 1, wherein said storage means is a hard disk.