JP2004096637A - Information updating method and interface device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propagate a new revocation list more surely with respect to equipment which are interconnected by the IEEE 1394 interface. <P>SOLUTION: When a topology constituted of nodes Node #A, #B and #C is connected to a topology constituted of nodes Node #D, #E and #F, the lists in list managers Node #B and Node #D, each representing the node having an identical list in each topology, are compared with each other simultaneously with the connection, As a result of the comparison, an old list List 2 is updated to a new list List 3. Using the updated list, list manager Node #B updates the list in the neighboring Node #A to the List 3, and the Node #A updates the list in the neighboring node Node #C to the List 3. Because the list update processing is started simultaneously with the connection, the entire lists in the topology can be surely updated. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an information updating method and an interface device for appropriately updating registration information of an unauthorized device possessed by a device connected in one topology.
[0002]
[Prior art]
2. Description of the Related Art In recent years, digital interfaces based on the IEEE (Institute of Electrical and Electronic Engineers) -1394 standard, which can transmit information signal packets and control signal packets serially and at high speed, have become widespread. An interface based on the IEEE-1394 standard (hereinafter abbreviated as IEEE 1394 I / F) is for transferring digital content data such as image data and audio data at high speed using isochronous transfer, which is a transfer method that guarantees real-time performance. Is possible.
[0003]
In addition, the IEEE1394 I / F supports hot-line insertion / removal in which a cable can be inserted / extracted while power is turned on. Further, in the IEEE 1394 I / F, a topology in which a plurality of star-type topologies are connected is supported as a connection mode (topology), and a connection mode with a higher degree of freedom can be selected. That is, in the IEEE 1394 I / F, not only daisy chain connection but also tree connection can be obtained as the topology.
[0004]
In the transfer of digital content data using the IEEE 1394 I / F, a high-quality copy can be easily created because there is no deterioration of the content data. Therefore, from the viewpoint of copyright protection, more secure copy protection technology is required. Therefore, a standard regarding copy protection at the time of transmitting digital contents, which is called DTCP standard (Digital Transmission Content Protection Specification), has been established. According to the DTCP standard, each device has a list, called a revocation list, in which an unauthorized device is registered with respect to copy protection, so that transmission / reception of content to the unauthorized device is prevented. Stipulated.
[0005]
Devices having the IEEE 1394 I / F include devices that must have a revocation list and devices that do not have a revocation list. Devices capable of processing content data that is never permitted to be recorded must have a revocation list. For example, a digital television receiver capable of outputting content data that is never permitted to be recorded to the outside corresponds to a device that must have this revocation list. On the other hand, in a digital VTR (Video Tape Recorder) and the like, there are both devices that must have a revocation list and devices that do not have a revocation list.
[0006]
By the way, the revocation list needs to be updated as an unauthorized device is newly found. The revocation list updating method is roughly divided into the following three methods.
[0007]
The first is a method of updating the revocation list from the written medium. The second is a method of updating from a stream including a revocation list transmitted through broadcasting or the Internet.
[0008]
A third method is to update between devices connected by an IEEE 1394 cable. In the IEEE 1394 I / F, when devices are already connected by a cable (hereinafter, 1394 cable) compliant with the IEEE 1394 I / F, the devices connected to each other are mutually authenticated according to the specification of the connected device. Key exchange is performed, and data transfer is enabled. For example, when this authentication and key exchange processing is performed between devices, the revocation list between devices is compared, and the revocation list is received from the device having the newer list, so that the revocation list is Be updated. In this way, a new list is propagated between devices, and the list is updated.
[0009]
For example, a device whose revocation list has not been updated is connected to a device whose revocation list has been updated by the above-described first method or second method, and authentication and key exchange are performed. The revocation list of the device is updated.
[0010]
[Problems to be solved by the invention]
However, in the third method, the revocation list cannot be updated unless authentication between the devices is performed. Therefore, a newer list than the revocation list owned by the user is stored on the same topology connected by the IEEE 1394 I / F. There is a problem that the revocation list cannot be updated even if there is a device possessed, unless an authentication process is performed with the device.
[0011]
There is a security problem in that devices having revocation lists on the same IEEE 1394 topology may not have the same list. Therefore, there has been a demand for a method for more reliably propagating a new revocation list.
[0012]
Accordingly, an object of the present invention is to provide an information updating method and an interface device that can more reliably propagate a new revocation list to devices connected to each other by the IEEE 1394 I / F.
[0013]
[Means for Solving the Problems]
According to an embodiment of the present invention, in order to solve the above-mentioned problem, a tree-type connection is possible, and in an information updating method using an interface corresponding to hot-swap, a first list and a second list of a first device are provided. A comparing step of comparing the second list of the second device with the second list, and an updating of updating the older list with the newer one of the first and second lists based on the comparison result of the comparing step. And a step of comparison, wherein the step of comparison is performed at the same time as the connection between the first device and the second device.
[0014]
According to a fifth aspect of the present invention, there is provided an interface device capable of performing tree-type connection and capable of hot-swapping, comprising: a connecting means for hot-swapping and tree-type connecting to other devices; And a first list held by the list holding unit and a second list held by the other device at the same time when the connection unit is connected to another device by the connection unit. And updating the older list with the newer one of the first and second lists based on the comparison result.
[0015]
According to a sixth aspect of the present invention, in the information updating method using an interface compatible with hot-swapping, which is capable of tree-type connection, a first topology in which one or a plurality of devices each holding a list are connected. Is connected to a second topology to which one or a plurality of devices each holding a list are connected, and the first list manager which is a device for managing a list in the first topology holds the list. A comparing step of comparing the list with a list held by a second list manager which is a device managing the list in the second topology; and a first list manager holding the list based on a comparison result of the comparing step. Updating the older list with the newer one of the list to be updated and the list held by the second list manager And updating the list held by one or more devices in the topology to which the list manager belongs by updating the list held by the list manager after the updating of the list by the updating step. is there.
[0016]
As described above, according to the first or fifth aspect of the present invention, the first device and the second device are connected, and at the same time, the first list and the second device of the first device have The second list is compared with the second list, and based on the comparison result, the newer one of the first and second lists is updated with the older one. Therefore, for each device in the topology, New lists can be reliably propagated.
[0017]
According to the invention described in claim 6, a first topology in which one or a plurality of devices each holding a list is connected, and a second topology in which one or a plurality of devices each holding a list are connected When a topology is connected, a list held by a first list manager that is a device that manages a list in the first topology, and a second list that is a device that manages a list in the second topology Comparing the list held by the manager with the newer one of the list held by the first list manager and the list held by the second list manager based on the comparison result; After updating the list, the list held by one or more devices in the topology to which the list manager belongs is updated by the list held by the list manager. Because you have so that, even when the topology are connected to each other, can be propagated for each device in each topology ensures a new list.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example of the configuration of an IEEE 1394 functional board 120 applicable to an embodiment of the present invention. The configuration of which an example is shown in FIG. 1 is implemented, for example, in a device such as a digital television receiver or a digital video recorder compliant with the IEEE 1394 standard.
[0019]
A CPU (Central Processing Unit) 101, a RAM (Random Access Memory) 102, and a ROM (Read Only Memory) 103 are connected to the internal CPU bus 100. The CPU 101 controls the entire operation of the IEEE 1394 function board 120 based on a program (firmware) stored in the ROM 103 in advance. The ROM 103 also stores in advance identification information (device ID) for identifying the device. The RAM 102 is used as a work memory of the CPU 101, for example. The RAM 102 can be used as a non-volatile memory by always backing up with a battery power supply or the like.
[0020]
The entire operation of the IEEE 1394 function board 120 is controlled by the CPU 101 communicating with the outside via the control signal data bus 107. The control signal data bus 107 is connected to, for example, a control unit of a device such as a digital television receiver on which the IEEE1394 function board 120 is mounted.
[0021]
The IEEE 1394 functional board 120 functionally includes three layers, a physical layer, a link layer, and a transaction layer, and a serial bus management. Among these, the transaction layer and the serial bus management are realized by the above-described firmware, and the physical layer and the link layer are realized by the physical layer unit 105 and the link layer unit 104, respectively. The physical layer unit 105 and the link layer unit 104 are each configured by, for example, an integrated circuit of one chip.
[0022]
A physical layer unit 105 is connected to the internal CPU bus 100 via a link layer unit 104. In the link layer unit 104, a stream is exchanged with the outside via the TS signal data bus 109. For example, when the IEEE 1394 function board 120 is mounted on a digital television receiver, digital video signals are exchanged via the TS signal data bus 109.
[0023]
One or a plurality of connectors (hereinafter, referred to as 1394 connectors) 106A, 106B, and 106C conforming to the IEEE 1394 standard are connected to the physical layer unit 105. The physical layer unit 105 performs signal processing between the electric signal transmitted / received via the 1394 connector and the link layer unit 104. The physical layer section 105 defines mechanical interfaces such as the 1394 connectors 106A, 106B and 106C and 1394 cables, encodes and decodes the analog signals converted by the link layer section 104 into analog / digital signals, and converts the communication signals into electrical signals. The provision of an electrical interface such as a signal level for determining a level, arbitration for determining a communication node, resynchronization of a communication clock, detection of initialization of a bus, and the like are performed.
[0024]
The link layer unit 104 performs signal processing between the physical layer unit 105 and the transaction layer. In the link layer unit 104, packet assignment for address assignment, data check, data frame division, and cycle control are performed. The isochronous data is processed without passing through the transaction layer.
[0025]
The transaction layer performs signal processing between the upper application and the link layer unit 104. The link layer unit 104 performs processing such as reading, writing, and locking data on the upper application. That is, by transmitting a request packet and receiving a response packet using the processing of the link layer unit 104, one communication processing for the designated node and address is performed. In the transaction layer, communication processing from another node to itself, such as reception of a request packet and transmission of a response packet, is also performed.
[0026]
The serial bus management controls all three layers described above. In the IEEE 1394 function board 120, when a tree structure changes due to the connection of a plurality of devices, a configuration occurs. The serial bus management includes a configuration ROM in which the configuration is held and a CSR (Control and Status Register) used as a control register. As these configuration ROMs and CSRs, for example, registers in the RAM 103 and the CPU 101 can be used.
[0027]
In such a configuration, when a plurality of IEEE 1394 function boards 120 are connected by a 1394 cable, a bus is formed and a topology is formed. In the IEEE 1394 I / F, a tree type can be used as a form of this topology. The formation of a topology in the IEEE 1394 I / F will be schematically described.
[0028]
For example, when another IEEE 1394 function board 120 is connected to the 1394 connector 106A by a 1394 cable, first, a bus reset signal is output from the 1394 connector 106A and all topology information is cleared. Next, tree identification is performed by exchanging predetermined signals between devices connected by the 1394 cable, thereby forming a tree. Each device (IEEE 1394 functional board 120) constituting the tree is called a node, a node located at the end of the tree is called a leaf node, and a node located in the middle is called a branch node. When the tree identification is completed, self-identification processing is performed, and each node is given a unique physical identifier in the topology. Thereby, the position of each device in the topology can be specified.
[0029]
According to the present invention, the revocation list of devices in the same topology connected by IEEE 1394 is always updated to the latest list in the same topology. I do.
[0030]
At this time, since it is necessary to manage the revocation list in the same topology, if there is a device having the revocation list in the same topology, one device that manages the revocation list in the same topology is set. The device set to manage the revocation list is called a list manager. When the revocation lists of all devices in the same topology have the same contents, the list manager notifies all the devices in the same topology that the revocation list has been updated.
[0031]
Hereinafter, a revocation list updating method according to an embodiment of the present invention will be described in more detail. First, a revocation list (hereinafter, appropriately referred to as a list) will be schematically described. The revocation list exists in a message called a System Renewability Message, which is provided in a device (IEEE 1394 device) compatible with the IEEE 1394 I / F. The System Renewability Message has generations, and the size of a list that can be held varies depending on the generation.
[0032]
FIG. 2 illustrates an example of the First-Generation (1st generation) System Renewability Message. In the message, the Generation field indicates the generation of the message, and the Version field describes the version (Version Number) of the message. Next, a revocation list, that is, a list List of IDs of unauthorized devices is described. At the head of the unauthorized device list List, the data length of this list is described. Following the unauthorized device list List, information Signature for determining whether this message is correct is described.
[0033]
Such a revocation list is held, for example, in the RAM 102 of FIG.
[0034]
3 to 18 show various examples of the revocation list updating method. In these FIGS. 3 to 18, List0, 1,... Indicate revocation lists, and a list having a larger value is a newer revocation list. Each of the nodes #A, #B,... Corresponds to a device having the IEEE 1394 function board 120. In FIGS. 3 to 18, a node with “● (black circle)” indicates a list manager, and a node with “ノ ー ド (white circle)” has been a list manager in the past. Indicates that the node is no longer the list manager during the revocation list update process. Note that the list manager basically has the same device before and after the bus reset.
[0035]
FIG. 3 is an example in which two nodes Node #A and Node #B are independent of each other without being connected by the IEEE 1394 I / F. In this case, node Node # A and node Node # B are each a list manager. Here, node Node # B has a revocation list List0, and node Node # A has a newer revocation list List1. When the node Node # A and the node Node # B are connected, their revocation lists are compared, and as shown in the upper part of FIG. 4, the list List0 of the node Node # B is updated to a newer list List1. You.
[0036]
For example, when node Node # A and node Node # B are connected, packets are transmitted by broadcast to each other in order to set a list manager. In the transmission by broadcast, a packet is simultaneously broadcast to all devices in the same topology.
[0037]
When a packet is broadcast-transmitted by both devices (Node Node #A and Node Node #B), revocation list update processing is performed. A new revocation list is transmitted from a device having a newer revocation list to a device having an old revocation list. In the device having the old list, the list is updated by, for example, overwriting the old revocation list with the transmitted new revocation list. In this example, the node Node #B having the old list is set as a new list manager.
[0038]
In order to update the revocation list, the following two packets are required.
(1) A packet having information necessary to determine whether to update the list
(2) Packet for updating the list
[0039]
Among these, the packet of (1) is a packet including Generation information and Version information of the System Renewability Message of the device to which the packet has been transmitted, and information Signature for confirming the validity of the message itself. It is. The packet of (2) is the System Renewability Message itself. In this case, the legitimacy is confirmed by the information Signature in the System Renewability Message.
[0040]
Consider adding a node Node # C shown in the lower part of FIG. 4 to the configuration in the upper part of FIG. The node Node # C has a newer revocation list List2 than the revocation lists of the nodes Node # A and Node # B. Further, the node Node # C that exists alone is itself a list manager.
[0041]
In this case, as shown in an example in FIG. 5, first, the revocation lists are compared between the list managers, that is, between the node Node # A and the node Node # C. In the example of FIG. 5, since List2 of the node Node # C is newer than List1 of the node Node # B, the revocation list List1 of the node Node # B is updated by the list List2 of the node Node # C, The list is List2.
[0042]
After the revocation list of the node Node # B is updated to the list List2, the revocation list List1 of the node Node # A in the same topology as the node Node # B is changed to the list List2 of the node Node # B. The list is updated and becomes List2.
[0043]
In this way, the revocation list is checked for a newly added device in the topology, and when the revocation list of the added device is new, the revocation list of all devices in the topology is checked. Need to be updated. If the revocation list of the newly added device is older, the revocation list of the added device is of course updated.
[0044]
The determination as to whether or not the revocation list needs to be updated is made based on the version (Version Number) in the above-described System Renewability Message. That is, the versions are compared with each other, and the list having the newer version is transmitted from the device having the newer version list to the device having the older version list. In the device having the old version list, the revocation list is updated by overwriting the transmitted new version list with the old version list.
[0045]
As a method of knowing which device is the list manager in the same topology, a first method of transmitting a packet indicating the fact from the list manager to all devices in the topology by broadcasting, A second method is conceivable in which a value is set in a register to indicate that the device is a list manager.
[0046]
In the first method, a packet including Generation Information and Version information of the System Renewability Message possessed by the list manager, that is, a list of the two packets necessary for updating the revocation list is described above. A packet having information necessary for determining whether or not to update is broadcast-transmitted in the same topology. This allows each device in the same topology to identify the list manager and to know the old and new of the revocation list of its own with respect to the revocation list of the list manager. The list managers receive the packets from each other, thereby acquiring the other party's Generation information and Version information, and can perform the revocation list update processing.
[0047]
Next, a case where a plurality of topologies are connected to form one topology will be described. For example, consider the case where the topology shown in FIG. 5 and the topology shown in FIG. 6 described above are connected by a node Node # B and the topology shown in FIG. 7 is formed. Here, in FIG. 6, the node Node # D and the node Node # F are connected to the node Node # D, and the node Node # D is a list manager. Further, the node Node # D, the node Node # E, and the node Node # F have the same revocation list List3.
[0048]
The revocation lists of the devices in the topology shown in FIG. 5 are all List2, which are the same. Similarly, the revocation lists in the topology shown in FIG. 6 are all List3, which are the same. Therefore, the revocation list can be updated only by comparing the revocation lists of the nodes Node # B and Node # D, which were the list managers of the two topologies before the two topologies were connected.
[0049]
In this example, as a result of the comparison, the list of the node Node # B is updated using the list of the node Node # D because the list of the node Node # B is older than the list of the node Node # D. At this time, of the two list managers, the node Node # B having the old revocation list is set as the new list manager.
[0050]
Here, the person having the old revocation list is the list manager, but this is not limited to this example, and the person having the new list can be the list manager. Since the list manager performs a procedure for updating the revocation list, when the device having the old revocation list is used as the list manager, the status of the revocation list in the topology is grasped. This is easy and is preferable.
[0051]
Subsequently, the list of the node Node # A is updated by the node Node # B, and the list of the node Node # C is updated by the node Node # A. In this way, even when a plurality of devices are added, the revocation list is compared between the list managers, and the revocation list is updated for all devices in the topology for which the list manager required the list update. Done.
[0052]
As described with reference to FIGS. 3 to 7, the revocation list is updated every bus reset, so that the revocation lists of all devices in the topology are always updated to the latest list in the topology. be able to.
[0053]
When the device is separated from the topology, no particular operation is required. However, when the list manager is separated from the topology, a new list manager is set.
[0054]
An update procedure when the revocation list needs to be updated for a plurality of devices as in the examples of FIGS. 5 and 7 will be described with reference to FIG. In FIG. 8, each of the node Node # A, the node Node # B, the node Node # C, and the node Node # E has a revocation list List0. Node Node # D is a device that does not have a revocation list.
[0055]
It is assumed that a node Node # F having a revocation list List1 is connected to the topology configured by the nodes Node # A to #E. Since the revocation list of the newly connected node Node #F is newer than the revocation list of the nodes Node #A to #E, the revocation list of the node Node #F uses the revocation list of the nodes Node #A to ##. E needs to be updated.
[0056]
First, since the node Node # F is connected to the topology including the nodes Node # A to #E, the revocation list is compared between the node Node # F and the node Node # A which is the list manager. As a result of the comparison, the list of the node Node # A is determined to be older than the list of the node Node # F, and the list needs to be updated for the nodes Node # A to #E. The list List0 of the node Node # A is updated by the list List1 of the node Node # F, and becomes the list List1 (SEQ1).
[0057]
Next, the revocation list of the neighboring device, that is, the device directly connected to the node Node #A is updated by the node Node #A (SEQ2). In the example of FIG. 8, the list is updated for the node Node # B and the node Node # D. At this time, since the node Node # D does not have the list, the node Node # A updates the list with respect to the device (node Node # E) adjacent to the node Node # D (SEQ3). . The list is updated by the node Node # B with respect to the adjacent device (node Node # C) (SEQ4).
[0058]
Devices that need to update the revocation list, such as the nodes #B, #C, and #E in FIG. 8, notify the list manager when the list update is completed. For devices that do not need to update the list, such as the node Node # F, it is considered that the list has been updated, and the list manager is notified that the list has been updated. When the list manager receives notification from all the devices in the topology that the list update has been completed, the list manager notifies all the devices in the topology that the revocation list update has been completed. You.
[0059]
Next, a process when the topology changes while the revocation list is being updated will be described.
[0060]
First, a process when a new device is added to the topology while updating the revocation list will be described. As an example, the topology shown in FIG. 10 is obtained by adding a node Node # C having a newer list List2 to the topology including the node Node # B and the node Node # A having the revocation list List1 shown in FIG. Is formed, and the topology shown in FIG. 11 is added to the topology shown in FIG. That is, the node Node # B, which is the list manager of the topology shown in FIG. 11, is connected to the node Node # B, which is the list manager of the topology shown in FIG.
[0061]
In the process of shifting from FIG. 9 to FIG. 10, it is necessary to update the revocation list List1 of the node Node # A and the node Node # B with the list List2 of the node Node # c. At this time, when the topology of FIG. 11 is connected to the topology of FIG. 10 at the time when the list of the node Node # A is not updated as shown in FIG. 10, the node Node # B and the node which are the list managers of the respective topologies are connected. Based on the new / old relationship of the revocation list of Node #D, three cases shown in FIGS. 12, 13 and 14 can be considered.
[0062]
FIG. 12 shows an example in which the node Node # B and the node Node # D, which are the list managers of the respective connected topologies, have the same revocation list. In this case, since there is no need to update the revocation list between the list managers, the list of the node Node #A, which was interrupted during the processing in FIG. 9, is updated. The list manager of the new topology is node Node # B.
[0063]
FIG. 13 shows an example in which the revocation list of node Node # B is older than the list of node Node # D. In this case, the node Node # A is updated to a newer list by the node Node # B again, so that the suspended node Node # A is not updated at this time.
[0064]
That is, first, the list List2 of the node Node # B is updated to the list List3 by the list List3 of the node Node # D (SEQ10). Next, the list List1 of the node Node # B is updated to the list List3 of the node Node # A by the list List3 of the node Node # B (SEQ11), and further, the list List2 of the node Node # C is updated by the updated list List3 of the node Node # A. Is updated to the list List3 (SEQ12). The list manager of the new topology is the node Node #B having the old revocation list.
[0065]
FIG. 14 shows an example in which the revocation list of node Node # B is newer than the list of node Node # D. In this case, after the list of node Node # D is updated by the list of node Node # B, the list of node Node # E and #F is updated by the list of node Node # D. At the same time, the list of the interrupted Node #A is updated with the list of the Node #B.
[0066]
That is, first, the list List0 of the node Node # D is updated to the list List2 by the list List2 of the node Node # B (SEQ20). Then, the list List0 of the node Node # D is updated to the list List2 by the updated List2 of the node Node # D (SEQ21), and the list List0 of the node Node # F is changed to the list List2 by the list List2 of the node Node # D. (SEQ22). On the other hand, the suspended update of the list List1 of the node Node # A is resumed by the list List2 of the node Node # B (SEQ23), and the list List1 of the node Node # A is updated to the list List2. The list manager of the new topology is the node Node #D having the old revocation list. In the example of FIG. 14, SEQs 21, 22, and 23 can be processed in parallel.
[0067]
Next, a description will be given of a process performed when the topology is divided while the revocation list is being updated. As an example, the topology shown on the left side of FIG. 15 is composed of nodes #B, #A, #C, #D, and #E each having a revocation list List1, and the node Node #B is a list manager. Are connected to a single node Node # F, and a topology as shown in FIG. 16 is formed.
[0068]
When the topology of FIG. 16 is formed, the revocation list is compared between the node Node # B which is the list manager of the topology shown on the left side of FIG. 15 and the node Node # F which is the single node. In the example of FIG. 15, since the revocation list List2 of the node Node # F is newer than the list List1 of the node Node # B, the list List1 of the node Node # B is changed according to the list of the node Node # F. The list is updated to List2. Thereafter, the revocation list is updated by the node Node # B with respect to the devices adjacent to the node Node # B, that is, the node Node # A and the node Node # D.
[0069]
At this time, a case where node Node # D is separated from the topology shown in FIG. 16 while the revocation list of node Node # D is updated, and the topology is divided into two topologies shown in FIGS. Think. In this case, processing differs depending on whether a list manager exists in the divided topology.
[0070]
FIG. 17 shows an example in which a list manager exists in a divided topology. In this case, the device whose revocation list has been updated and the device whose revocation list has not been updated are grasped by the node Node # B which is the list manager. Therefore, the list is updated by the list manager for a device whose revocation list has not been updated. In the example of FIG. 17, it can be seen that the node Node # C is older than the list List2 in the node Node # B and the list List1 of the node Node # C is not updated, so that the node Node # B which is the list manager has The list List1 of the node Node # C is updated to the list List2 by the list List2.
[0071]
FIG. 18 shows an example in which a list manager does not exist in the divided topology. In this case, it is necessary to newly set a list manager in the topology. One of the devices whose revocation list has already been updated is set as a new list manager.
[0072]
For example, in a device in which the revocation list is updated before the topology is separated in the separated topology, a process for setting itself as a list manager, such as setting a predetermined register value, is arbitrarily performed. Is When the device that has performed this process disconnects the topology, the fact is broadcast in the topology. When this processing is performed by a plurality of devices in the topology, for example, the device that broadcasts the list manager setting earliest may be the list manager.
[0073]
A device whose revocation list has not been updated requests the list manager thus set to update the list. When no device serving as the list manager appears in the topology after a certain period of time, it is considered that no device whose revocation list has been updated in the topology exists. In this case, for example, the above-described method is performed on all devices in the topology, so that any one device in the topology is set as the list manager.
[0074]
By the above operation, the revocation lists in the topology are all updated to the same newer one.
[0075]
FIG. 19 is a flowchart illustrating an example of the revocation list update process described above. First, when a new device is connected to the topology in step S10 (hereinafter referred to as the original topology), the bus is reset according to the IEEE 1394 rules, and the device is added to all the devices in the topology in the topology. Then, it is recognized that the topology has been changed (step S11). In step S12, it is determined whether all devices in the new topology are themselves list managers. If it is determined that the user is not the list manager, the process proceeds to step S18 described later.
[0076]
At the time of this step S12, there are two list managers in the topology formed by connecting new devices, a list manager in the original topology and a list manager in the topology of the newly added device group. become.
[0077]
On the other hand, if it is determined in step S12 that the device itself is the list manager, the processing of the device proceeds to step S13. In step S13, a packet including Generation information and Version information is broadcast-transmitted from the list manager, that is, itself to all devices in the topology. Further, in the next step S14, similarly to step S13, a packet including Generation information and Version information is broadcast transmitted from the other list manager. That is, the list manager broadcasts a packet and receives a packet from the other list manager.
[0078]
In step S15, it is determined whether the revocation list needs to be updated based on the packets broadcasted from both list managers in steps S13 and S14 described above.
[0079]
If it is determined that all devices in the topology including the newly added device have the same revocation list based on the Generation information and Version information in the packet, the list is updated. It is determined that there is no need to perform the process, and the process proceeds to step S21. In step S21, in order to make one list manager in the topology, one of the list managers on the original topology and the newly added device is released from functioning as a list manager.
[0080]
On the other hand, if it is determined in step S15 that the revocation list is different between the newly added device and the original topology, it is determined that the list needs to be updated, and the process proceeds to step S16. Will be migrated to. In step S16, the revocation list is transmitted from the list manager having the new revocation list to the list manager having the old list based on the Generation information and the Version information in each other's packets. The list manager having the old revocation list that has received this revocation list updates the old list with the received new list.
[0081]
When the revocation list is updated in step S16, the process proceeds to step S17, in which the new topology has the new revocation list among the list manager of the original topology and the list manager of the newly added device. The other list manager is defeated as a list manager. This makes the remaining list manager the only list manager in the topology.
[0082]
In the next step S18, the list manager identified as the only one in the topology in step S17 sends the list manager to the device next to the list manager, that is, the device directly connected to the list manager. The revocation list is transmitted. The revocation list of the device adjacent to the list manager is updated by the revocation list transmitted from the list manager.
[0083]
In the next step S19, the device whose list has been updated by the revocation list transmitted from the list manager transmits a revocation list to a device adjacent to the device. The list of the neighboring devices is updated by the transmitted revocation list. When the list is updated, the adjacent device notifies the list manager of the update.
[0084]
In the next step S20, it is determined whether or not the revocation lists of all devices in the topology have been updated. If it is determined that the revocation lists of all devices in the topology have been updated, a series of processing ends. On the other hand, if it is determined that a device whose revocation list has not yet been updated exists in the topology, the process returns to step S19, and a list of devices next to the device whose revocation list has been updated immediately before is displayed as: Updated as described above. In this way, the device whose list has been updated further updates the list of adjacent devices, and eventually reaches the end (leaf) of the topology, and the list of all devices in the topology is updated.
[0085]
In the above description, an example in which the IEEE 1394 I / F is applied to the present invention has been described, but the present invention is not limited to this example. INDUSTRIAL APPLICABILITY The present invention can be applied to other interfaces that can be hot-plugged and can take a tree-type connection form. For example, the present invention can be applied to a USB (Universal Serial Bus).
[0086]
Furthermore, in the above description, the information exchanged and updated between nodes is described as information relating to unauthorized information equipment, but this is not limited to this example, and other information is exchanged between nodes and updated. Is also good.
[0087]
【The invention's effect】
As described above, according to the present invention, a list manager for managing a revocation list is provided in a topology connected by the IEEE 1394 I / F, and adjacent devices are sequentially determined based on the revocation list of the list manager. Is updated, the revocation list list of the entire topology can be kept up-to-date and the same.
[0088]
Conventionally, devices having a new revocation list and devices having an old revocation list may coexist in the same topology connected by the IEEE 1394 I / F. At this time, if an unauthorized device that is listed in the new revocation list but not listed in the old revocation list exists in the same topology, the device with the old revocation list is There was a danger that data could be exchanged. However, according to the present invention, as described above, since the revocation list in the topology is always kept up-to-date and the same, there is an effect that such a risk can be avoided.
[0089]
That is, by using the present invention, all devices in the same topology connected by the IEEE 1394 I / F have the same revocation list, and the entire topology can communicate with unauthorized devices registered in the revocation list. There is an effect that the exchange can be blocked.
[0090]
Further, according to the present invention, the revocation list is updated every time the topology is changed, so that the possibility of a newer revocation list being propagated more quickly and widely is increased, and the security is improved. effective.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an example of a configuration of an IEEE 1394 I / F applicable to an embodiment of the present invention.
FIG. 2 is a schematic diagram illustrating a configuration example of a message including a revocation list.
FIG. 3 is a diagram for explaining a revocation list updating method.
FIG. 4 is a diagram for explaining a revocation list updating method.
FIG. 5 is a diagram for explaining a revocation list updating method.
FIG. 6 is a diagram for explaining a revocation list updating method.
FIG. 7 is a diagram for explaining a revocation list updating method.
FIG. 8 is a diagram for explaining a revocation list updating method.
FIG. 9 is a diagram for explaining a revocation list updating method.
FIG. 10 is a diagram for explaining a revocation list updating method.
FIG. 11 is a diagram for explaining a revocation list updating method.
FIG. 12 is a diagram for explaining a revocation list updating method.
FIG. 13 is a diagram for explaining a revocation list updating method.
FIG. 14 is a diagram for explaining a revocation list updating method.
FIG. 15 is a diagram for explaining a revocation list updating method.
FIG. 16 is a diagram for explaining a revocation list updating method.
FIG. 17 is a diagram for explaining a revocation list updating method.
FIG. 18 is a diagram for explaining a revocation list updating method.
FIG. 19 is a flowchart illustrating an example of a revocation list update process.
[Explanation of symbols]
101: CPU, 102: RAM, 103: ROM, 104: Link layer unit, 105: Physical layer unit, 106A, 106B, 106C: 1394 connector

Claims (10)

Tree-type connection is possible, and in the information updating method with the interface corresponding to hot swapping,
A comparing step of comparing the first list of the first device with the second list of the second device;
An updating step of updating an older list with a newer one of the first and second lists based on a comparison result obtained by the comparing step;
The information updating method, wherein the comparing step is performed simultaneously with the connection of the first device and the second device. The information updating method according to claim 1,
The information updating method, wherein the list is a revocation list in which information indicating an unauthorized device is registered. The information updating method according to claim 1,
If a third device is further connected to the topology composed of the first and second devices during the updating in the updating step, the current update is interrupted and the An information updating method, wherein a connection process is performed. The information updating method according to claim 3,
After the connection processing, the third list of the third device is compared with the newer list based on the comparison result in the comparing step, and as a result of the comparison, the third list is updated with the newer list. And updating the new list with the third list and resuming the interrupted step of updating with the updated new list. An information updating method, characterized in that: In an interface device that can be connected in a tree type and supports hot swapping,
Connection means for connecting to another device so as to be hot-swappable and tree-type connectable;
List holding means for holding the first list,
At the same time when the connection unit is connected to another device, the first list held in the list holding unit is compared with the second list held in the other device. An interface device, wherein an older one of the first and second lists is updated based on a newer one of the first and second lists. Tree-type connection is possible, and in the information updating method with the interface corresponding to hot swapping,
When a first topology in which one or a plurality of devices each holding a list is connected and a second topology in which one or a plurality of devices each holding a list are connected, the first topology is connected. The first list manager, which is the device that manages the list in one topology, and the second list manager that is the device that manages the list in the second topology. A comparing step to compare with the above list;
An updating step of updating an older list with a newer one of the list held by the first list manager and the list held by the second list manager based on a comparison result obtained in the comparing step. Have
An information updating method, wherein after updating the list in the updating step, the list held by one or more devices in the topology to which the list manager belongs is updated by the list held by the list manager. The information updating method according to claim 6,
The information updating method, wherein the list is a revocation list in which information indicating an unauthorized device is registered. The information updating method according to claim 6,
The information updating method, wherein the list manager manages one or more devices in a topology to which the list manager belongs so as to hold the same list as the list held by the list manager. The information updating method according to claim 6,
During the updating in the updating step, a third topology in which one or a plurality of devices each holding a list are connected to a new topology including the first and second topologies. The information updating method is characterized in that the updating is interrupted and the connection processing of the third topology is performed. The information updating method according to claim 9,
After the connection processing, a list held by a third list manager, which is the device that manages the list in the third topology, is compared with the newer list based on the comparison result in the comparing step. If the result of the comparison is that the list held by the third list manager is newer than the newer list, the newer list is updated with the list held by the third list manager; An information updating method, wherein the interrupted updating step is restarted using the updated newer list.

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