JP3800058B2 - Gateway device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gateway device that connects two different types of networks and enables data to be exchanged between them. In particular, the present invention comprises an information network constructed by an information device such as a PC and a digital AV device. The present invention relates to a gateway apparatus suitable for controlling an AV device from an information device by combining with an AV system network.
[0002]
[Prior art]
With the development of information home appliances and the widespread use of the Internet, it has become possible to construct a network in ordinary households.
One form of network at home is an information network that aims to share Internet access and printers, etc. by multiple PCs, such as PCs for individual families or desktop PCs and notebook PCs. Among them, there are Ethernet LANs using twisted pair lines such as 100BASE-TX and wireless LANs based on the IEEE802.11b standard, and TCP / IP widely used in computer networks such as the Internet is generally used as a protocol on the network. Yes. Hereinafter, such an information network using TCP / IP is called an IP network.
[0003]
On the other hand, the digitalization of AV devices represented by TVs, VTRs, etc. has progressed, and digital satellite broadcast receivers and TVs incorporating the same, digital recording VTRs, video cameras, and hard disks that use hard disks as recording media ( Recording devices using optical disks such as HD) recorders and DVD-RAMs have appeared. In order to take advantage of the characteristics of the digital system that signal quality deterioration during transmission and storage hardly occurs in these digital AV devices, an increasing number of devices adopting a high-speed serial interface (hereinafter referred to as 1394 IF) based on the IEEE 1394 standard for connection between the devices. . 1394IF was originally designed as a bus for PC peripheral layer devices, but it is an isochronous transfer mode suitable for transmitting video and audio data handled by AV devices without interruption, with a data transfer rate of up to 400 Mbps. Has been attracting attention as a standard interface for digital AV devices, because it has the advantage of reducing the user's operation by automatically assigning device IDs by detecting cable insertion and removal. For this reason, a protocol for transmitting MPEG2-TS (Transport Stream) widely used in digital AV devices, a data format, and a command transmission / reception protocol for controlling AV devices are defined as IEC61883 standards. Control command specifications for each device, for example, VTR and tuner, are also defined by 1394TA (Trade Association), which is a dissemination group, as an AV / C (Audio Video Control) command.
[0004]
Such AV / C commands are specific to 1394IF, and in order to operate a digital AV device by a PC connected to the above-described IP network, the method of mounting the 1394IF on the PC or the IP network It is necessary to use a method of transmitting an operation request to the digital AV apparatus via a gateway apparatus connected to both 1394 IFs.
Japanese Patent Application Laid-Open No. 2000-224207 and Japanese Patent Application Laid-Open No. 2001-202317 describe a method of controlling a digital AV device or the like connected to the 1394 IF using a controller on an IP network using such a gateway device.
[0005]
[Problems to be solved by the invention]
According to the above-described conventional technique, when an operation is to be performed from the controller, a control request is sent from the controller to the gateway device, and the gateway device converts the control request into a control request for an AV device or the like connected by the 1394 IF. To control the operation of the AV apparatus. Therefore, it is necessary for the gateway device to incorporate in advance conversion means in accordance with the required control request conversion method in accordance with the control specifications of the AV device connected by the 1394 IF. For this reason, there is a problem that an AV device or the like in which the gateway device does not have information on control specifications cannot be operated from a controller on the IP network.
[0006]
The object of the present invention is to control the AV device to be controlled by the gateway when controlling the AV device connected by the 1394 IF from the controller on the IP network via the gateway connected to both the IP network and the 1394 IF. It is an object of the present invention to provide a gateway apparatus configuration method that does not need to incorporate a combined control request conversion means.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a conversion table for associating an IP address for specifying a device connected to the 1394 IF with a node ID of the 1394 IF in the gateway device connected to both the IP network and the 1394 IF. A device on the 1394 IF that receives a control request issued from the controller on the IP network to the IP address at the gateway, converts the IP address into a node ID according to the conversion table, and directly controls the data part of the control command. The control from the controller is performed by transferring to
[0008]
DETAILED DESCRIPTION OF THE INVENTION
An example of an embodiment of the present invention will be described with reference to FIG. FIG. 1 shows a system configuration of a home network using a gateway device according to an embodiment of the present invention. In the figure, a digital TV 101 is a gateway device in the present invention, and connects a network of digital AV devices based on 1394 IF and an IP network based on Ethernet and wireless LAN.
[0009]
A VTR 102, an HD (hard disk) recorder 103, and a video camera 104 are connected to a network based on 1394 IF, a router 111 and a PC 112 are connected to a LAN using Ethernet, and a wireless LAN IF 114 provided in the router 111 is connected to a wireless LAN IF 113. It is connected to the portable information terminal 113 that it has. The router 111 has a router function for connecting a home network and a wide area network and a wide area network access function such as an ADSL modem or a cable modem, and is connected to the Internet 200 via the Internet service provider 201.
Note that the gateway 111 does not have to be an integrated router and modem, and these may be provided as separate devices. A mobile phone terminal 203 having an Internet access function is connected to the Internet 200, so that it is possible to connect to an IP network in the home from outside the home.
[0010]
FIG. 2 is a block diagram showing an example of a detailed configuration of the digital TV 101 according to an embodiment of the present invention. A CPU 301 that performs overall control is connected to a tuner 303, a decoder 304, a graphics processing unit 305, a memory 307, a 1394 IF unit 308, a network IF unit 309, and a remote control IF 310 via a system bus 302. A program received from the antenna is selected by the tuner 302, restored to a video signal by the decoder 304, and sent to the display unit 306 via the graphics processing unit 305. A display unit 306 is a monitor display such as a CRT or a liquid crystal panel, and displays the video restored by the decoder 304 on the screen. Note that the display unit 306 is not necessarily integrated with the digital TV 101, and may be an external monitor display.
[0011]
The 1394 IF 308 is connected to an AV apparatus such as the VTR 120 via the 1394 IF, and transmits a control command to each AV apparatus or receives an operation state of each apparatus according to a command from the CPU 301. Also, video / audio data sent from each AV device is received and sent to the decoder 303, and the video signal is restored and displayed on the display unit 306. Also, the video / audio data output from the tuner 302 is sent to the 1394 IF for recording. The network IF 309 receives control data sent from the IP network or sends response data.
The remote control IF 310 receives a code representing a user operation sent from the infrared remote control 311 and sends it to the CPU 301 to generate control data necessary to control the operation of the digital TV 101 or the AV device connected to the 1394 IF. Necessary processing is performed in the CPU 301.
[0012]
FIG. 3 shows the configuration of software operating on the CPU 301 of the digital TV 101 according to an embodiment of the present invention. The digital TV function application 401 controls functions inherent to the receiver, such as broadcast reception. An operation input from the user is received from the remote control driver 411 and an operation screen is displayed using the graphics driver 412.
The network device operation application controls other AV devices connected on the 1394 IF, implements a user interface using the remote control driver 411 and the graphics driver 410, and controls the devices connected to the network by the 1394 IF. AV / C command data, which is a command for the communication, is passed to the FCP (Function Control Protocol) packet processing unit 405, and the AV / C command is issued to the AV device on the network via the 1394 driver 409. Execute the operation.
[0013]
The network driver 408 passes the data received from the IP network to the TCP / IP processing unit 407, checks the IP address and port number of the transmission destination, and sends this to the data conversion processing unit 404 if it is a control request for the AV device. The data portion of the control request is taken out, transferred to the FCP packet processing unit 405, and sent to the 1394 IF as an AV / C command via the 1394 driver 409. Conversely, when an AV / C response, which is a response to the AV / C command, is received from the 1394 IF, it is passed to the FCP packet processing unit 405, and the response is a response to the command issued from the network device operation application 402. Or a response to the result of converting the control request received from the IP network, the data sent to the network device operation application 402 or the data conversion processing unit 404 according to the result, and the data sent to the data conversion processing unit 404 Is further sent to the TCP / IP processing unit 407 and sent as data on the IP network from the network driver 408 to the IP network.
[0014]
When a new device is connected to the 1394 IF or a device that has been connected is removed, the device detection unit 406 notifies the network device operation application 402 and the address management unit 403 of this. The address management unit 403 internally holds an address management table indicating a correspondence relationship between the IP address, the node ID of the 1394 IF, and the node unique ID. The data received by the TCP / IP processing unit 407 is 1394 IF. It is referred to in order to determine whether or not the request is a control request for the connected AV apparatus, and to convert the data transmission source or destination IP address and the 1394 IF node address in the data conversion unit 404.
[0015]
FIG. 4 shows an example of the data contents of the address management table held by the address management unit 403 according to the embodiment of the present invention. The address management table shows the correspondence between the IP address 501, the node unique ID 504, and the node ID 505 for each device connected to the 1394 IF. 4 shows an example in which IPv6 is used as the IP address. The 128-bit IP address 501 is divided into a 64-bit subnet prefix 502 and a 64-bit interface ID 503.
The node unique ID 504 is a unique identification number assigned to each device corresponding to the 1394 IF at the time of manufacture, and is composed of a manufacturer ID of upper 24 bits and a device ID of lower 40 bits. The node ID 505 is an identification number dynamically assigned to each device.
[0016]
When a new device is added to or deleted from the 1394 IF network, a bus reset is generated and transmitted to each device, and a node ID is automatically assigned to each device. When a bus reset occurs, the device detection unit 406 checks the node unique ID of each device on the network using the 1394 IF, notifies the correspondence between the node ID and the node unique ID to the address management unit, and creates an address management table. As a result of checking the node unique ID, when a new device is added, the upper 7 bits are used locally in the interface ID portion of the IP address value of the device based on the value of the node unique ID. A value changed to 1 indicating the ID is written, IP address assignment processing is executed in the same manner as when a new device having this interface ID is added on the IP network, and the subnet given from the router Write the prefix value to the address management table.
[0017]
In this way, it appears as if a new device has been added on the IP network, and the controller on the IP network can access the device on the 1394 IF using the assigned IP address. . In order to indicate access from a device on the IP network to a device connected by 1394 IF, an appropriate port number is determined, and data addressed to this port number is processed by the data conversion unit 404.
[0018]
FIG. 5 shows a packet format of an AV / C command transmitted / received via the 1394 IF. The AV / C command is specified by 1394TA (Trade Association), and is issued from the controller to the target device as an 1394IF Asynchronous packet according to the FCP (Function Control Protocol) protocol and packet format defined in the IEC61883 standard. The
An AV / C command packet includes a packet header portion 601 and a command / response data portion 602. The packet header portion follows the format of an Asynchronous block write packet defined in the IEEE 1394 standard, and includes a destination node ID 603, a transaction label 604 for identifying a match between a transaction request and a response, a retry code 605 indicating a retry state, data writing / reading, etc. It consists of a transaction code 606 indicating distinction, a priority 607 indicating packet priority, a transmission node ID 608, a reception address offset 609 indicating a destination address of the reception node, a data length 610, an extended transaction code 611, and an error check CRC 612.
[0019]
The command / response data 602 includes a CTS code 613 that indicates the type of command code, a command type 614 that indicates the type of control command / status read command / response, and a subunit type that indicates the type of the AV device such as a TV, VTR, or tuner. 615, a subunit ID 616 for identifying a subunit in the apparatus, an operation code 617 indicating a command type, operands [1] to [n] 618, 619, 620 which are command parameters, a zero padding unit 621, and a CRC 622 Composed.
[0020]
FIG. 6 shows a packet format of a control request sent from the controller on the IP network to the AV device connected to the 1394 IF of the gateway device. The control request is an IPv6 datagram having a TCP packet as data, and includes an IPv6 header portion 701, a TCP header portion 702, and command / response data 602. The IPv6 header 701 includes an IP version 703, a traffic class 704 indicating priority, a flow label 705 for distinguishing packet handling, a payload length 706 indicating data size, and a next header 707 indicating the type of header that follows. It consists of a hop limit 708 indicating the hop limit number, a source address 709, and a destination address 710.
[0021]
The TCP header 702 includes a source port number 711, a destination port number 712, a sequence number 713 indicating the order of TCP packets, a reception confirmation sequence number 714 indicating the next packet to be received, and a data offset indicating the head of the TCP data portion. 715, reserved field 716, control bit 717 for storing TCP communication control information, window size 718 for flow control, error check checksum 719, urgent pointer 720 indicating the position of urgently used data, TCP communication It comprises an option 720 indicating the type of option. The command / response data is the same as the content of the AV / C command described above.
[0022]
FIG. 7 shows a command and response transmission / reception sequence between the controller on the IP network, the gateway, and the target AV device. First, when a control command in the format shown in FIG. 6 is issued toward the IP address of the AV apparatus to be operated by the controller, the control command is received at the gateway, and the address management table shown in FIG. 4 is searched.
If there is an address that matches the IP address column 501 of the address management table, it is issued as an AV / C command using the command data part of the control command as it is to the corresponding node ID, and the AV device that is the operation target A command is sent to (target). At this time, the data conversion unit 404 records the IP address of the command issuing source and the node ID as the destination as a command being issued in the list.
[0023]
The AV device that has received the command executes an operation corresponding to the command, and transmits the result as an AV / C response specifying the node ID of the gateway. The gateway examines the transmission node ID and transaction label of the received AV / C response to determine whether it is a response to a command issued by itself or a response to a control request received via the IP network, and passes through the IP. In the case of a response to the control request received in step S3, the IP address of the control request issuance source recorded in the data conversion unit 404 is checked, and the data part of the AV / C response received for the IP address is used as it is. A control response as data is issued and the recorded IP address and node ID pair is deleted from the command list being issued.
In the specification of the AV / C command, a period from when the target receives a command until it issues a response is determined to be within 100 milliseconds. However, when executing a command that takes a long time to complete the operation, such as a VTR tape operation, an intermediate (INTERIM) response is issued once within 100 milliseconds, and a final response is issued after the actual operation is completed. It is stipulated.
[0024]
FIG. 8 shows a command / response transmission / reception sequence when issuing such an intermediate response. In this case, the IP address / node ID conversion and command / response data transfer method are the same as those described above. However, when the intermediate response is received at the gateway and transferred to the controller, it is not deleted from the command list being issued recorded in the data converter, and is held until the final response is transferred. deep.
[0025]
FIG. 9 shows a sequence in the case where a control request is issued to the same target from two controllers on the IP network. First, a control command is issued from the controller A to the target, and the IP address and node ID are converted and the packet is transferred at the gateway. Next, when a control command is issued from the controller B to the same target, and the previously issued control command from the controller A is before completion of execution, a command list being issued recorded in the gateway is displayed. Since it can be determined by reference that the target is processing a command, the target is being processed for controller B without issuing a control request from controller B as an AV / C command to the target. Returns a busy response indicating. In this way, since two or more commands are not transferred to the same target at the same time, it is possible to prevent the controller to which a response from the target is returned from becoming unidentifiable.
[0026]
As described above, according to the gateway device according to the embodiment of the present invention, the AV device connected by the 1394 IF can be controlled via the gateway by the controller connected to the IP network. At this time, the gateway converts the destination of the control command from the IP address to the node ID of 1394 IF, and the command and response data are transferred in the same format, so the information about the control specifications of the AV device to which the gateway itself is the target. It is not necessary to have. Therefore, the AV device that can be operated from the controller is not limited by the information of the gateway itself, and the controller side operation application is also supported for an AV device for which a control specification by a new command is defined in the future. It is possible to operate via a gateway. Further, the AV device to be controlled need only support reception of control commands by the 1394 IF without being aware of operations from the IP network.
[0027]
In the above example, the case where IPv6 is used as the IP network has been described. The present invention is not affected by the nature of an IP network based on IPv4. In FIG. 6, the control request issued by the controller uses a TCP packet. However, the present invention is not limited to this, and can be implemented using a UDP packet, for example.
[0028]
【The invention's effect】
According to the present invention, when the AV device connected by the 1394 IF is controlled from the controller on the IP network via the gateway connected to both the IP network and the 1394 IF, the control specification of the AV device to be controlled by the gateway is set. It is not necessary to incorporate a combined control request conversion unit in advance, and any AV device that supports AV / C can be controlled from the controller.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a home network according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of a digital TV which is a gateway device according to an embodiment of the present invention.
FIG. 3 is a block diagram showing a software configuration of a digital TV which is a gateway device according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating a configuration of an address conversion table provided in a gateway device according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating a data format of AV / C commands and responses.
FIG. 6 is a diagram showing a data format of control commands and responses on the IP network.
FIG. 7 is a sequence diagram illustrating a command transmission / reception order among a controller, a gateway, and a target.
FIG. 8 is a sequence diagram showing a command transmission / reception order accompanied by an intermediate response among a controller, a gateway, and a target.
FIG. 9 is a sequence diagram illustrating a command transmission / reception order between two controllers, a gateway, and a target.
[Explanation of symbols]
101 ... Digital TV (gateway device)
112 ... PC (controller)
113 ... Form information terminal (controller)
203 ... form telephone terminal (controller)
403 ... Address management unit 404 ... Data conversion unit 405 ... FCP packet processing unit 406 ... Device detection unit 407 ... TCP / IP processing unit 408 ... Network driver 409 ... 1394 driver

Claims (6)

In a gateway device that realizes data exchange between each other by combining a first network and a second network having different address systems,
An address management means comprising an address management table indicating a correspondence between a network address in the first network format and a network address in the second network format;
The control request destination address specified by the first network address is converted into the second network address according to the address management table, and the control request issuer network address and the control request are When the response indicating the execution result for the control request is received from the second network address, it is recorded that it is being issued to the second network address. Conversion means for converting the destination on the network to the network address of the issuer of the control request and deleting the record;
A response to the control request received from the second network, sent to the second network without changing the data portion of the control request addressed to the second network address converted by the conversion means A data transmission / reception data processing unit for a second network that is taken out for transmission to the first network;
The control request received from the first network is referred to the address management table to determine that it is a control request addressed to a device connected to the second network, and is passed to the conversion means for the data processing. A transmission / reception data processing unit for the first network that returns the response to the control request extracted by the conversion unit to the source of the control request according to the destination of the response converted by the conversion unit. Gateway device.   2. The gateway apparatus according to claim 1, wherein the first network is an IP network that specifies an address by an IP address, and the second network is a network configured by apparatuses connected by an IEEE1394 interface. .   When a device is added to or deleted from the second network, an entry is added to or deleted from the address management table, and when a new device is added, a new network address in the first network is acquired. The gateway apparatus according to claim 1, wherein an access request for the address is received, converted into an access request for the newly added apparatus, and sent to the second network.   2. The gateway apparatus according to claim 1, wherein the control request transmitted on the second network and the received response are AV / C commands and responses defined on IEEE1394.   When another control request is received from the controller on the first network for the device on the second network recorded as issuing the control request in the conversion means, the other control request is sent 2. The gateway apparatus according to claim 1, wherein a response indicating that it cannot be received is returned to the controller.   When an intermediate response to the control request sent on the second network is received, the intermediate response is sent to the first response without deleting the information indicating that the control request is being issued recorded in the conversion means. 2. The information indicating that the control request is being issued, which is recorded in the conversion means, is deleted when a final response to the control request is received after being sent out on the network of claim 1. The gateway device described.

Images