JP2001075851A - Device and method for transmission, device and method for reception, and system and method for transmission and reception - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conveniently manage the dependence of update information on a directory server side. SOLUTION: When transmitting side management information is updated, the count value of a container entry where an update has occurred in its subordinate is increased by one, and update information including the name of the container where the update occurs in its subordinate, update contents and the count value just before the update is generated and transmitted by a multiple address network. In a receiving side, when the count value included in the received update information coincides with a count value accompanying an entry to which receiving side management information corresponds, the receiving side management information is updated by the received update information, and a count value accompanying an entry in which the receiving side management information is updated is increased by one. Meanwhile, when the count value does not coincide, the update information is regarded as being unexpectedly dropped with carelessness, and the update due to the received update information is postponed until update information whose count value coincides is received. The receiving side can check the unexpected drop of update information with carelessness simply by increasing a count value in every update on the transmitting side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission apparatus, a transmission method, a reception apparatus, and a transmission method which have a hierarchical structure and are suitable for simultaneously broadcasting data distributed and arranged on a network. The present invention relates to a receiving method, a transmitting / receiving system, and a transmitting / receiving method.

[0002]

2. Description of the Related Art Various methods have been proposed for data distribution. For example, on the current Internet, TCP / IP (Transmission Control Protocol) such as http (Hyper Text Transfer Protocol) has been proposed.
/ Internet Protocol). In TCP / IP, a call is made from a receiving side receiving data distribution to a transmitting side of data, and a connection is established between the transmitting side and the receiving side every time data is transmitted and received. It is supposed to be. Therefore, highly reliable data can be distributed. On the other hand, the load on the transmission side and the network may increase, and it may be difficult to perform efficient data distribution.

[0003] That is, when the number of terminals receiving data is increased and access to the server that provides the data is concentrated, a heavy load is imposed on the server and the network. It could take a lot of time.

[0004] Therefore, for example, a satellite line or a CATV (Cab) capable of broadcasting data over a wide area can be used for data distribution.
le Television) lines, and terrestrial digital broadcasting that is expected to be put into practical use.
In this case, the load on the server and the network is not affected by the increase in the number of terminals.

On the other hand, in recent years, with the development of digital communication networks such as the Internet, enormous data has been accumulated on networks, and there is a demand for efficient use of this enormous data. Therefore, a directory service for hierarchically managing data distributed on a network and providing the data to users has been attracting attention. By using the directory service, users can quickly find the information they need from information distributed on the network,
It becomes possible to access.

[0006] The directory service is based on, for example, the international standard OSI (Open Systems Interconnection). It is defined as 500 series.
X. According to 500, the directory is a collection of open systems, and each open system cooperates,
It is defined as having a logical database of information about a set of real-world objects.

X. According to the main directory service 500, it is possible to search and browse information stored in the directory. In addition, for example, a directory like a telephone directory and user authentication are also provided by the directory service. Further, in directory services, objects are named so that they are easy to remember, guess and recognize, especially for human users.

[0008] The X. The 500 directory service is very comprehensive, has a very large program size, and is very difficult to implement on the Internet using TCP / IP as a protocol. for that reason,
A lightweight directory service for TCP / IP such as LDAP (Lightweight Directory Access Protocol) has been proposed.

In the directory service, data is managed based on a directory structure having a tree structure.
The directory structure includes a container entry corresponding to a node between data and a leaf entry at the end of the tree and having substantial data. A container entry can have other container entries and leaf entries under its own. A leaf entry cannot have another entry under it. An entry representing the entire tree is called a root entry.

As an example, the genre is classified according to the container entry, and the leaf entry contains more specific data of the genre represented by the immediately above container entry.

In recent years, it has been proposed to provide the above-mentioned directory service using data transmission means for performing the above-mentioned simultaneous broadcasting, that is, a satellite line, CATV line, digital terrestrial broadcasting, or the like. In this case, the information by the directory service is provided in one direction, and the user cannot request information. Therefore, the same information is repeatedly transmitted as the directory information by the directory service. On the user side, the transmitted information is connected to, for example, a television receiver or the like, and used as an IRD (Integrated
Reciever Decoder) and STB (Set Top Box).

Here, synchronization of information between the directory server side and the user side, that is, synchronization management will be considered.
The directory server detects substantial directory updates and responds to dynamic changes in the directory hierarchy. The directory information reflecting the change in the hierarchical structure of the directory is transmitted to the user. At this time, if all the directory information is transmitted, the data amount becomes enormous, so that only the difference of the change is extracted and transmitted.

On the directory server side, every time an update of directory information is detected, or at regular intervals,
The update information including the change difference is transmitted to the user. The user always receives the update information based on the directory update and updates the accumulated directory information with the received difference update data, so that the directory information can be synchronized between the directory server and the user. .

[0014]

At this time, it is assumed that the user is in a hibernation state for some reason, for example, the power of the receiver is not turned on, and the update information from the directory server cannot be received for a certain period of time. I do. For example, as shown in FIG. 12, update information Msg1, Msg2 and Msg
3 are transmitted in order. The update information Msg2 is a difference from the directory information updated by the update information Msg1, and the update information Msg3 is the update information Msg2.
Is the difference with respect to the directory information updated by.

On the other hand, when the receiving side is in a pause state as shown near the center of FIG. 12, the receiving side has not been able to acquire the update information Msg2. In such a case, on the receiving side, the update information Msg1 is updated using the update information Msg3, and the information is inconsistent between the directory server and the receiver without being correctly updated. There is.

That is, the update information Msg2 depends on the update information Msg2, and the update information Msg3 is
g2. The above-described inconsistency occurs because the dependency between Msg1 to Msg3 is not correctly reflected.

In order to prevent the occurrence of such inconsistency, a list of update information that must be already processed before processing based on the update information, that is, a list of update histories, is added to the update information to be transmitted. It has been proposed to transmit in addition to the update information. On the receiving side, by following the dependency of the update information based on the update history, the updating process can be performed so that there is no inconsistency with the directory structure managed on the receiving side.

However, the method of adding the update history to the update information has a problem that the directory server must manage the dependency of the update information and the update history and add the update history information to the update information. there were.

This causes a problem that, as the directory structure managed on the server side becomes large, the load on the server side increases and the amount of data to be transmitted also increases.

Therefore, an object of the present invention is to provide a transmitting apparatus, a transmitting method, a receiving apparatus, a receiving method, and a transmitting / receiving system and a transmitting / receiving method for easily managing update information dependency on the directory server side. To provide.

[0021]

According to the present invention, there is provided a transmitting apparatus for transmitting directory data for managing the location of contents in a tree-structured data structure, comprising a plurality of entries. Directory storage means for storing directory data having a tree-structured data structure; directory operation means for updating directory data stored in the directory storage means; and contents of update of directory data updated by the directory operation means. Update information generating means for generating update information; and transmitting means for transmitting the update information generated by the update information generating means to the broadcast network, wherein a plurality of entries of directory data stored in the directory storage means are stored. Each time an update occurs directly below itself Has a value that indicates the change to the update phase, the update information generating means is a transmitting apparatus characterized in that to include in the update information generated a value indicating an update stage.

According to the present invention, in a transmission method for transmitting directory data for managing the location of contents in a tree-structured data structure, the directory data composed of a plurality of entries and having a tree-structured data structure is stored in a directory. Means for updating the directory data stored in the directory storage means, and generating update information for generating update information representing the contents of the update of the directory data updated by the directory operation step. And a transmission step of transmitting the update information generated in the update information generation step to the broadcast network, wherein each of the plurality of entries of the directory data stored in the directory storage means is directly under its own. Every time an update occurs Has a value that indicates the change to the update phase, the update information generation step is a transmission method is characterized in that to include in the update information generated a value indicating an update stage.

According to the present invention, there is provided a receiving apparatus for receiving directory data for managing the location of contents in a tree-structured data structure, the directory comprising a plurality of entries and having a tree-structured data structure. Directory storage means for storing data; receiving means for receiving update information for updating directory data stored in the directory storage means; and storage means for storing in the directory storage means based on the content of the update information received by the reception means. Update operation means for updating directory data to be stored, and each of the plurality of entries of the directory data stored in the directory storage means,
The update operation means has a first value indicating an update stage, which changes every time an update occurs immediately below itself, and the update operation means has a second value indicating the update stage included in the update information received by the reception means. Comparing the value with the first value, and updating the directory data stored in the directory storage means based on the update information received by the receiving means when the first value matches the second value. Is a receiving device.

According to the present invention, there is provided a receiving method for receiving transmitted directory data in which the location of contents is managed in a tree-structured data structure, the directory comprising a plurality of entries and having a tree-structured data structure. Storing the data in the directory storage means, receiving the update information for updating the directory data stored in the directory storage means, and storing the directory based on the content of the update information received in the receiving step Updating the directory data stored in the directory storage means, wherein each of the plurality of entries of the directory data stored in the directory storage means has an update which changes each time an update occurs immediately below itself. A first value indicating the stage, and And comparing the first value with the second value indicating the update stage of the update information received by the receiving step, and when the first value and the second value match, the receiving And updating the directory data stored in the directory storage means based on the update information received in the step (i).

Further, the present invention relates to a transmission / reception system for transmitting directory data for managing the location of contents in a tree-structured data structure and for receiving the transmitted directory data. First directory storage means for storing first directory data having a structure; directory operation means for updating the first directory data stored in the first directory storage means; Update information generating means for generating update information representing the content of the update of the first directory data;
Transmitting means for transmitting the update information generated by the update information generating means to the broadcast network; and a second directory configured by a plurality of entries and storing second directory data having a tree-structured data structure Storage means, reception means for receiving update information transmitted to the broadcast network by the transmission means, and second directory data stored in the second directory storage means based on the contents of the update information received by the reception means Update operation means for updating a plurality of entries of the first directory data stored in the first directory storage means. The update information generation means has a first value indicating the stage of the update in the generated update information. , Each of the plurality of entries of the second directory data stored in the second directory storage means has a second value indicating an update stage that changes each time an update occurs immediately below itself, The update operation means includes a first update information included in the update information received by the reception means.
Is compared with the second value. When the first value and the second value match, the second value stored in the second directory storage means based on the update information received by the receiving means. The transmitting and receiving system is characterized in that the directory data is updated.

According to the present invention, there is provided a transmitting / receiving method for transmitting directory data for managing the location of contents in a tree-structured data structure and receiving the transmitted directory data. First directory data with a structure
Storing the first directory data stored in the first directory storage means, updating the first directory data stored in the first directory storage means, and updating the first directory data updated in the directory operation step. An update information generation step of generating update information representing the contents, a transmission step of transmitting the update information generated in the update information generation step to the broadcast network, and a plurality of entries,
Storing second directory data having a tree-structured data structure in second directory storage means;
A receiving step of receiving the update information transmitted to the broadcast network by the transmitting step; and a second directory data stored in the second directory storage means based on the content of the update information received by the receiving step. An update operation step of updating, wherein each of the plurality of entries of the first directory data stored in the first directory storage means performs an update step that changes each time an update occurs immediately below itself. A first value indicating the stage of the update, wherein the first value indicating the stage of the update is included in the generated update information;
Each of the plurality of entries of the second directory data stored in the directory storage means of the second means indicates an update stage which changes every time an update occurs immediately below itself.
And the update operation step compares the first value and the second value of the update information received by the receiving step, and the first value and the second value match. sometimes,
A transmission / reception method characterized by updating second directory data stored in a second directory storage unit based on update information received in a receiving step.

As described above, claims 1 and 2
The invention described in the above is stored in the directory storage means,
The directory information having a tree-structured data structure, which is configured by a plurality of entries, is configured to transmit update information representing the content of an updated update to the broadcast network, and the transmitted update information includes: Each of the plurality of entries of the directory data stored in the directory storage means has a value indicating the stage of update that changes each time an update occurs immediately below itself, so that the value is included on the receiving side. From the received update information, it is possible to know the stage of the update made to the directory data stored in the directory storage means.

According to a third aspect of the present invention, there is provided the present invention is characterized in that directory data having a plurality of entries and having a tree-structured data structure stored in a directory storage means is stored in the received update information. Each of the plurality of entries of the directory data stored in the directory storage means has a first value indicating a stage of update, which changes each time an update occurs immediately below itself. , The first value is compared with a second value indicating an update stage of the update information, and the first value is compared with the second value.
The directory data stored in the directory storage means is updated based on the received update information when the value of When the stage of updating the stored directory data matches,
The directory data is updated based on the received update information.

The invention according to claim 7 and claim 10 is characterized in that the first directory data, which is constituted by a plurality of entries and has a tree-structured data structure, is stored in the first directory storage means. When updated, the update information indicating the content of the update of the first directory data is stored in the first directory data stored in the first directory storage unit under each of a plurality of entries of the first directory data. A first value having a tree-structured data structure, which is transmitted to the broadcast network and includes a first value indicating an update stage which changes each time an update occurs, and stored in the second directory storage means. Update information for updating the second directory data is received from the broadcast network, and a first value included in the update information and a second directory storage When a plurality of entries of the second directory data stored in the row have a second value indicating a stage of the update, which changes each time an update occurs immediately below itself, the reception is performed. Since the second directory data stored in the second directory storage unit is updated based on the received update information, the update step based on the received update information and the directory data stored in the directory storage unit are updated. Is updated, the directory data is updated with the received update information.

[0030]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows a configuration of an example of a data distribution system applicable to the present invention. The transmission-side directory server 10 holds and manages directory data. The directory data managed by the transmission-side directory server 10 is a representation of real-world contents in a tree structure, and exists, for example, in a distributed manner on a higher-level network connected to the transmission-side directory server 10. The position information and the name of the content to be linked are associated with each other, and are represented in a tree structure.

The transmission-side directory server 10 can update the directory data by making changes such as addition, modification (update), and deletion to the managed directory data. For example, a change in the structure of the content in the real world is reflected in directory data managed by the transmitting-side directory server 10, and the directory data is changed.

The transmission-side directory server 10 supplies directory data managed by the server 10 to the reception-side directory servers 12, 12,... Via a broadcast network 11 such as a broadcast network.
Provide directory data to users. The directory data supplied from the transmitting directory server 10 to the receiving directory server 12 is stored in the receiving directory server 12.

The transmitting side directory server 10 and the receiving side directory servers 12, 12,... Are connected to each other by a bidirectional network 13. All or part of the directory data managed by the sending directory server 10 is supplied to the receiving directory servers 12, 12,... Via the broadcast network 11 and the bidirectional network 13 at a predetermined timing. . As a result, a change in directory data caused by the transmission-side directory server 10 can
, Are reflected in the transmission-side directory server 10 and the reception-side directory servers 12, 12,.
And the contents of the directory data are synchronized.

FIG. 2 conceptually shows the structure of directory data. Thus, the directory data is data having a tree structure. Among the nodes constituting the tree structure, those that can have further nodes under them are called container entries. On the other hand, a node that cannot have another node under it and is located at the lowest level is called a leaf entry. In FIG. 2, C1, C2, C3 and C4 are container entries, and L1, L2 and L
3 is a leaf entry. Each container entry and leaf entry are managed with names that can easily identify each other.

Although not shown, the container entry has an attribute of the container entry itself and a list of container entries and leaf entries under the container entry. The list of subordinate entries can also contain no elements. A container entry itself can have a plurality of attributes.
The leaf entry has a plurality of attributes of the leaf entry, and each attribute includes an attribute name and an attribute value. For example, when the leaf entry is content search information, one of the attribute names has an address, and the attribute value is URL.
(Uniform Resource Locator) is described.

FIG. 3 shows an example of the configuration of the directory server 10 on the transmitting side. This sending side directory server 10
Is composed of, for example, one computer or a plurality of computers connected to each other via a network or the like. The directory data having the structure shown in FIG. 2 described above is stored in the directory storage unit 21.

With respect to the directory data stored in the directory storage unit 21, the directory operation unit 20 can change the directory structure such as adding, updating, and deleting container entries and leaf entries. A user interface 22 including, for example, predetermined display means and input means is provided on the directory operation unit 20.
Is connected. The change of the directory structure is performed based on an instruction given by the user using the user interface 22.

A counter 23 is connected to the directory operation unit 20. The counter 23 counts the number of processes for each container entry and each leaf entry when the directory structure is changed by the directory operation unit 20. The count value for each container entry and each leaf entry is stored in the directory operation unit 2
0 to the directory storage unit 21 and stored.

The update information generation unit 24 generates directory structure update information in accordance with the change of the directory structure by the directory operation unit 20. The generated update information is stored in the update information storage unit 25. Update information of the directory structure will be described later.

The transmission unit 26 controls transmission of data to the broadcast network 11. The update information of the directory structure stored in the information update storage unit 25 is transmitted to the transmission unit 26.
Is repeatedly transmitted to the broadcast network 11. On the other hand, the directory data of the entire directory structure stored in the directory storage unit 21 is periodically transmitted from the transmission unit 26. Sender directory server 1
0 performs repetitive transmission of update information and periodic transmission of the entire directory structure in order to cope with missing update information in the receiving side directory servers 12, 12,.

The communication control unit 27 includes a bidirectional network 1
3 and controls communication on the bidirectional network 13. The bidirectional network 13 is transmitted from the receiving directory server 12 to the transmitting directory server 10.
For example, the missing update information is requested by the communication in the above. Based on this request, the transmission-side directory 10 extracts the corresponding update information from the update information stored in the update information storage unit 25, and stores the extracted update information under the control of the communication control unit 27. To the receiving-side directory server 12 via the.

The overall control unit 28 stores the directory storage unit 2
1, the control of the update information storage unit 25 and the transmission unit 26
And so on. When the directory data stored in the directory storage unit 21 is changed, the change is detected by the overall control unit 28. Based on the detection result, the corresponding update information is read from the update information stored in the update information storage unit 25 under the control of the overall control unit 28. The read update information is transmitted from the transmission unit 26 with the timing and the like controlled by the overall control unit 28.

FIG. 4 shows an example of the configuration of the receiving-side directory server 12. The receiving side directory server 12
For example, it is an STB or IRD located in each home, or a personal computer. The receiving unit 30 receives update information and directory data of the entire directory structure transmitted from the transmitting-side directory server 10 to the broadcast network 11. On the other hand, the directory storage unit 33 stores directory data configured based on information received in the past.

The information received by the receiving unit 30 is interpreted by the update operation unit 32. Based on the interpretation result, the update operation unit 32 updates the directory data stored in the directory storage unit 33.

The communication control unit 31 is a
3 and controls communication on the bidirectional network 13. For example, when the update information received by the receiving unit 30 is missing, the bidirectional network 1 is configured to transmit the missing update information by the update operation unit 32.
3, a request to the transmission-side directory server 10 is transmitted. The update information transmitted from the transmitting directory server 10 via the two-way network 13 based on this request is received by the receiving directory server 12 under the control of the communication control unit 31.

The directory operation section 34 has, for example, a user interface (not shown) including predetermined display means and input means, and displays the directory data stored in the directory storage section 33. The directory operation unit 34 is connected to the Internet, and the directory data is, for example, a URL (Uniform Resource Locate) indicating a method of accessing information on the Internet.
In the case of including r), it is also possible to access contents on the Internet based on the URL and display the accessed contents.

Next, updating of directory data will be described. For example, when the tree structure of the content in the real world is changed, the change is reflected in the directory data stored in the directory storage unit 21 of the transmission-side directory server 10, and the directory data is updated. Updating of directory data is performed by the directory operation unit 20. As described above, the update information is generated by the update information generation unit 24 when the directory data is updated.

FIG. 5 is a diagram for explaining an example of update of directory data and update information generated with the update. The directory data stored in the directory storage unit 21 is monitored at predetermined intervals by the overall control unit 28, and a change in the directory structure is detected. In this example, as shown in FIGS. 5A to 5D, it is detected that the directory structure has been changed, and the directory data stored in the directory storage unit 21 is stored in the tree 4.
It is updated in the order of 0A, 40B, 40C, and 40D.
5B to 5D, update information indicating the contents of the directory data update operation is shown.

In the initial directory structure, the tree 40
As shown in A, container entries C11 and C12 exist under the container entry C10.
A change occurs in the directory structure, and the tree 40A is updated like the tree 40B. That is, the leaf entry L11 is added under the container entry C11, and the leaf entry L12 is added under the container entry C12. Due to this change in the directory structure, FIG.
As shown in an example on the right side of B, update information 41A described as (C11, + L11) and update information 41B described as (C12, + L12) are generated as information indicating the content of the update operation. .

In this example, the expression of the update information is such that the target entry is written on the right side of the comma, and the change content is written on the left side of the comma. The symbol "+" indicates addition of an entry, and the symbol "-" indicates deletion of an entry. Of course, this is only an example, and the update information may be expressed in another notation.

The leaf entry L1 in the tree 40B
1 is moved from the subordinate of the container entry C11 to the subordinate of the container entry C12, and becomes a structure like a tree 40C. In other words, the leaf entry L11 is deleted from under the container entry C11, and the deleted leaf entry L11 is added under the container entry C12. At this time, the update information 42A of (C11, -L11) and the update information 42B of (C12, + L11) are generated.

Further, the leaf entry L12 in the tree 40C is moved from the position under the container entry C12 to the position under the container entry C11, and has a structure like the tree 40D. In other words, container entry C
12, the leaf entry L12 is deleted, and the deleted leaf entry L12 is replaced with the container entry C11.
Is added under In this case, (C11, + L1
The update information 43A of (2) and the update information 43B of (C12, -L12) are generated.

The receiving side directory servers 12, 12,...
.. Receives these update information via the broadcast network 11. For example, assuming that the directory data corresponding to the tree 40A is stored in the directory storage unit 33 in advance, the update operation unit 32 first uses the update information 41A and 41B received first under the container entry C11. The leaf entry L11 is added, and the leaf entry L12 is added under the container entry C12. In the same manner, by performing a process on the tree 40B in accordance with the update information 42A and 42B, the tree 40B is updated to generate a tree 40C, and the tree 40C is updated with the update information 43A and 43B.
Is performed, the tree 40C is updated, and the tree 40D is generated.

Here, as an example, consider a case where the receiving directory server 12 has missed the update information 42A and 42B. For example, update information 42A and 42B
When the receiving side directory server 12 is turned off and is not operating at the timing when is transmitted, the receiving side directory server 12 does not receive the update information 42A and 42B and the update information 42A and 42B are dropped.

When receiving the next transmitted update information 43A and 43B, the receiving-side directory server 12 cannot judge whether or not the previous update information, for example, the update information 42A and 42B has been missed. .

Therefore, the receiving side directory server 1
In 2, the update information 43A and 43
The update process is performed using 3B. That is, the leaf entry L12 is added under the container entry C11 based on the update information 43A, and the leaf entry L12 is deleted from the subordinate of the container entry C12 based on the update information 43B. As a result, the leaf entries L11 and L11 are stored under the container entry C11.
12, the leaf entry does not exist under the container entry C12, which contradicts the structure of the tree 40D shown in FIG. 5D. That is, inconsistency occurs between the directory data stored in the directory storage unit 21 of the transmission-side directory server 10 and the directory data stored in the directory storage unit 33 of the reception-side directory server 12.

According to the present invention, the transmitting-side directory server 12 manages sequential values for each container entry, thereby enabling the receiving-side directory server 12 to detect missing update information.

For each container entry, a counter is provided which increases the value by one each time a container entry and leaf entry under the container entry are updated. The state of the container entry can be expressed as follows by adding a count value to the container entry name (container entry name Cn, count value Sn).

The count value is counted by a counter 23 connected to the directory operation unit 20. For example, when the directory operation unit 20 updates the directory data, the counter 23 increases the count value of the management information of the target container entry by one. That is, the count value is a value that is incremented at each stage of updating the directory data by the update information, and indicates the stage of the update.

On the other hand, to the update information, the count value Sn of the container entry at the time when the update is detected is added to the above-described container entry name Cn where the update is detected and the update operation content. That is, the update information
Adds a container entry name Cn and a count value Sn to the content of an update operation, and (container entry name Cn,
Count value Sn, <contents of update operation>) For example, this is described as follows. Hereinafter, all the update information described above will be replaced with this update information '.

FIGS. 6 and 7 show a process of updating directory data when a count value is introduced for each container entry in the example shown in FIG.
The two columns on the left are information handled by the sending directory server 10. The column of transmission-side management information on the left end is directory data stored in the directory storage unit 21 of the transmission-side directory server. The second column from the left is the update information ′ generated by the update information generation unit 24.

The third and subsequent columns from the left are information handled by the receiving directory servers 12, 12,..., And the third column from the left contains the update information ′ transmitted from the transmitting directory server 10. This is reception update information received via the notification network 11. The receiving side management information in the rightmost column is directory data stored in the directory storage unit 33.

The transmission side and reception side management information is, for example, the tree 40A shown in FIG. 5 as shown in the uppermost row of the leftmost column in FIGS. 6 and 7, the container entry of the tree 40A. The states are listed and ((C1
(0, 0) (C11, 0) (C12, 0)).

FIG. 6 shows the receiving-side directory server 12,
12 is a sequence chart showing an example of a case where update information ′ is not missed in. The transmission-side directory server 10 increases the count value of the container entry in which the subordinate entry has been updated with the update information 'with respect to the transmission-side management information by one. In the 'update information', a count value immediately before updating is described. That is, the leaf entry L11 is added to the container entry C11 of the first transmission side management information 50, and the transmission side management information 52 is generated. Update information '51 generated at this time
Is the count value of the sender management information 50 immediately before being updated as the count value.

[0] is applied (C11,0,
+ L11). In the updated transmission-side management information 52, 1 is added to this count value, and the count value associated with the container entry C11 is set to [1].

Similarly, in this example, 3 subordinates are assigned to the subordinates of the container entries C11 and C12, respectively.
The counts of the container entries C11 and C12 are respectively set to “3” in the final transmission-side management information 54, and the count values of the container entries C11 and C12 in the update information '55 are: It is set to “2” based on the immediately preceding transmission side management information.

The receiving side directory servers 12, 12,...
.., The receiving side management information 57 stored in the directory storage unit 33 based on the received receiving update information 56.
Is updated. At this time, the count value Si described in the reception update information 56 is compared with the count value Sn of the reception side management information 57 attached to the container entry name Cn corresponding to the reception update information 56. As a result of the comparison, if they match, the reception side management information 57 and the reception update information 5
6 correspond to the received update information 5
6, the update processing of the receiving side management information 57 is performed. As a result of the update process, the receiving side management information 5 in which the count value Sn attached to the container entry C11 is set to [1].
8 is generated.

In the same manner, in the transmission-side directory server 10, every time the transmission-side management information is updated, update information ′ is generated, and the state of the container entry managed by the reception-side directory server 12 is changed. .
That is, the count value Si described in the received reception update information and the count value Sn attached to the container entry name Cn corresponding to the reception update information in the reception side management information.
Are compared, and if they match, the receiving side management information is updated with the receiving update information. Then, 1 is added to the count value Sn associated with the container entry updated by the reception update information in the reception side management information.

FIG. 7 is a sequence chart showing an example of a case where the update information ′ is partially missed in the receiving-side directory server 12. In the transmission-side directory server 10, the transmission-side management information 60 is updated, and transmission-side management information 62 is generated. At this time, the update information '61 is generated and transmitted. Further, the transmission side management information 62 is updated, and the transmission side management information 64 is generated. At this time, the update information '63 is generated and transmitted.

When the receiving side directory server 12 attempts to update the receiving side management information 65, the update information '61 has been missed. Therefore, the receiving side directory server 12 does not perform the update process using the update information '61 on the reception management information 65.
Next, the receiving side directory server 12 receives the update information '63 after the missing update information '61.

Here, the received update information 63 'from which the update information '63 has been received is stored in the container entries C11 and C1.
The count values associated with 2 are each “2”. On the other hand, in the receiving side management information 65, the count values associated with the container entries C11 and C12 are each “1”. That is, the count value of the reception update information 63 'is different from the count value attached to the container entry corresponding to the reception update information 63' of the reception-side management information 65. Therefore, the receiving side management server 65 is not updated with the receiving update information 63 'in the receiving side directory server 12.

As described above, the same update information ′ is repeatedly transmitted from the transmitting directory server 10. The receiving-side directory server 12 waits until the missing update information '61 is received, and waits for the update information '6.
When receiving 1, the receiving side management information 65 is updated using the received update information '61.

The received update information 63 ′ which has been received and has not been used for updating the receiving side management information is stored in, for example, a predetermined storage area of the directory storage unit 33, and the receiving side management information based on the update information '61 is stored. After updating, it may be used.

In the above description, the receiving-side directory server 12 has been described as waiting until the missing update information ′ is received. However, actually, the receiving-side directory server 12 misses the update information ′ based on, for example, the received update information 63 ′. Update information
If it is determined that there is a
Requests the transmitting side directory server 10 for the update information ′ that has been lost using the bidirectional network 13.

The transmitting directory server 10 fetches predetermined update information ′ from the update information storage unit 25 based on the request transmitted from the receiving directory server 12, and controls the bidirectional network 13 under the control of the communication control unit 27. To the receiving-side directory server 12 via the. The receiving side directory server 12 receives the update information ′ transmitted via the bidirectional network 13 and supplies the received received update information to the update operation unit 32 via the communication control unit 31. The update operation unit 32 uses the reception update information to update the corresponding reception-side management information.

Further, if the waiting time for waiting for the reception of the missed update information exceeds the preset timeout time, the request for the missed update information is sent to the transmitting side directory server 10 via the bidirectional network 13. Will be issued.

FIG. 8 is a flowchart showing an example of update processing of directory data in the transmission-side directory server 10. First, in the first step S10, the directory operation unit 20 operates the directory storage unit 21.
The update processing is performed on the subordinate of a certain container entry Cn in the directory data stored in. For example, a leaf entry or container entry immediately below a certain container entry Cn is deleted or modified, and a leaf entry or container entry is added immediately below a certain container entry Cn.

In the next step S 11, the count value Sn is extracted from the management information of the container entry Cn, and the update information ′ (container entry Cn, count value Sn, <update content>) is obtained using the extracted count value Sn. Generated. After generating the 'update information', in step S12,
One is added to the count value Sn of the container entry Cn.

The update information ′ generated in step S11 is stored in the update information storage unit 25, and transmitted to the broadcast network 11 by the transmission unit 26 at a predetermined timing, for example. At this time, as shown in an example in FIG. 9, the same update information ′ is repeatedly transmitted to the broadcast network 11 in consideration of the missing of the update information ′ in the receiving side directory server 12.

In FIG. 9, the passage of time is expressed from the left side to the right side, and the same number is assigned to the same update information 'transmitted from the transmitting side. The number assigned to the 'update information' indicates the order of updating the directory data. The period (period 101 and period 103) indicated by a bold line on the receiving side is a period during which the receiving side directory server 12 is operating, and the update information '
Is received. The other periods 100 and 102 are periods in which the receiving directory server 12 is inactive and the update information ′ is not received.

As shown in FIG. 9, from the transmitting side, 1
The update information No. to No. 6 are repeatedly transmitted. Period 1
At 00, the receiving side is at rest and the first and second update information ′ has been missed. The first and second update information 'are stored in a period 101 during which the receiving operation is performed by the receiving side.
However, since it is repeatedly transmitted, the receiving side can receive the first and second update information '. However, in the next period 102, the receiving side is at rest, and the third and fourth update information ′ is missed by the receiving side.

The third and fourth update information 'is also transmitted during the next period 103 in which the receiving side is operating. On the other hand, in the period 103, the fifth and sixth update information 'is transmitted before the third and fourth update information' is transmitted. On the receiving side, when the directory data updated by the above-mentioned No. 1 and No. 2 update information 'is updated using the previously transmitted No. 5 and No. 6 update information', the directory managed by the transmitting side is updated. The inconsistency described above occurs between the data and the directory data managed on the receiving side. In the present invention, the inconsistency is prevented from occurring by performing the processing already described with reference to FIGS.

FIGS. 10 and 11 are flowcharts showing an example of directory data update processing in the receiving-side directory server 12 when the above-described processing of FIGS. 6 and 7 is executed. The process of updating directory data by the receiving-side directory server 12 is divided into a receiving process for receiving the update information ′ (FIG. 10) and a timeout process for requesting the missing update information ′ (FIG. 11). These two processes are executed in parallel with each other.

First, a process of receiving update information 'will be described with reference to FIG. Prior to the execution of the flowchart of FIG. 10, the timer T omitted in FIG.
n is set at a predetermined time. The start and stop of the timer Tn are controlled by an instruction of the update operation unit 32. Note that the timer Tn is provided so that each of the container entries Cn stored in the directory storage unit 33 can be counted individually.

In the first step S20, in the receiving side directory server 12, the update information '(Cn, Si, <
Update content>) is received. [Cn] indicates a container entry name, and [i] indicates a count value. The received update information having received the update information ′ is supplied to the update operation unit 32, and the count value Si is extracted. The update operation unit 32 extracts the count value Sn included in the management information of the corresponding container entry Cn from the directory data stored in the directory storage unit 33. In the next step S21, the count value Si and the count value Sn are compared.

As a result of the comparison in step S21, if it is determined that the count value Si and the count value Sn match, the process proceeds to step S22. In step S22, if the timer Tn corresponding to the container entry Cn has been activated by the processing described later, the timer Tn is stopped, and in the next step S23, the reception update information obtained in step S20 is used. Thus, the directory data stored in the directory storage unit 33 is updated.

When the directory data is updated,
In the next step S24, a value obtained by adding 1 to the count value Si is set as the count value Sn attached to the updated container entry Cn of the directory data stored in the directory storage unit 33. When the count value Sn is updated in this way, a series of reception processing ends.

On the other hand, if it is determined in step S21 that the count value Si does not match the count value Sn, the process proceeds to step S25. Step S2
At 5, it is determined whether the timer Tn has been activated. If it is determined that the timer Tn has been activated, a series of reception processing ends. Step S2
If it is determined in step 5 that the timer Tn has not been started, the process proceeds to step S26, where the timer Tn is started,
A series of reception processing ends.

The flowchart in FIG. 10 is actually a loop process. That is, step S24,
After the processing of step S25 or step S26,
When a series of processes is completed, the process returns to step S20, and the next update information '(Cn, Si', <update content>)
Is started.

FIG. 11 is a flowchart of an example of the timeout process. As described above, the processing according to the flowchart in FIG. 11 is executed in parallel with the processing in the flowchart in FIG. Prior to the execution of this flowchart, the timer Tn is set to a predetermined time. If the time measured by the timer Tn exceeds the set time, it is determined that a timeout has occurred.

In the first step S30, it is determined whether or not the timer Tn has been started. As described above, the timer Tn stores the count value Si of the reception update information obtained in step S21 of FIG.
Is activated when the count value Sn associated with the corresponding container entry Cn, which is stored in the. That is, when the count value Sn and the count value Si do not match, it is considered that the update information ′ is missing in the receiving directory server 12.
The missing update information ′ is obtained by the following processing.

If the above-described step S30 determines that the timer T
If it is determined that n has not been activated, a series of timeout processes is terminated. The state where the timer Tn has not been started is a state where the timer Tn has been stopped by the processing of steps S20, S21 and S22 in the flowchart of FIG. 10 described above, and the obtained reception update information is appropriate. Means that

On the other hand, at step S30, if the timer T
If it is determined that n has been activated, the next step S3
At 1, it is determined whether the timer Tn has timed out. If it is not timed out, the process returns to step S30. Thus, the timer Tn
Checking again to see if has timed out
This is because the appropriate update information ′ is received before the activated timer Tn times out, and the timer Tn may be stopped according to the process of step S22 in the flowchart of FIG. 10 described above.

On the other hand, if it is determined in step S31 that the timer Tn has not timed out, the process proceeds to step S32. In step S32, the missing directory information '(Cn, Sn, <update content>) is requested from the receiving directory server 12 to the transmitting directory server 10 via the bidirectional network 13. Based on this request, the sending directory server 10
Requests the update information '(Cn, Cn,
Sn, <update content>) is transmitted.

The receiving side directory server 12 receives the update information '(Cn, Sn, <update content>) and uses the received update information' (Cn, Si, <update content>) to store the directory. The directory data stored in the unit 33 is updated (step S33). Then, in the next step S34, a value obtained by adding 1 to the count value Si is used as the count value Sn attached to the updated container entry Cn of the directory data stored in the directory storage unit 33. . Then, in step S35, the timer Tn is stopped, and a series of timeout processing ends.

[0095]

As described above, according to the present invention, when updating directory data managed on the receiving side based on updating of directory data managed on the transmitting side, the update of each container entry is performed. A counter indicating the number of times is provided. Then, on each of the transmitting side and the receiving side, the count value of the counter is increased every time an update occurs in the entry immediately below the container entry. Therefore, the receiving side can compare the count value included in the update information transmitted from the transmitting side with the count value of the container entry managed on the receiving side without managing the history of the updating information on the transmitting side. This makes it possible to determine whether or not the update information has been missed, and to apply the update information in an appropriate order.

[Brief description of the drawings]

FIG. 1 is a schematic diagram schematically showing a configuration of an example of a data distribution system applicable to the present invention.

FIG. 2 is a schematic diagram conceptually showing the structure of directory data.

FIG. 3 is a block diagram illustrating a configuration of an example of a transmission-side directory server.

FIG. 4 is a block diagram illustrating an example of a configuration of a receiving-side directory server.

FIG. 5 is a schematic diagram for explaining an example of update of directory data and update information generated with the update;

FIG. 6 is a sequence chart showing a process of updating directory data when a count value is introduced for each container entry.

FIG. 7 is a sequence chart showing a process of updating directory data when a count value is introduced for each container entry.

FIG. 8 is a flowchart illustrating an example of an update process of directory data in a transmission-side directory server.

FIG. 9 is a schematic diagram illustrating transmitting the same update information to a broadcast network.

FIG. 10 is a flowchart showing an update process of an example of directory data in a receiving directory server. 9 is a flowchart illustrating an example of a receiving process of receiving update information.

FIG. 11 is a flowchart illustrating an example of a process of updating directory data in a receiving-side directory server. It is a flowchart which shows an example of the timeout process which requests | requires the missing update information '.

FIG. 12 is a schematic diagram for explaining an example of missing update information.

[Explanation of symbols]

Reference numeral 10: transmission-side directory server, 11: broadcast network, 12: reception-side directory server
13 bidirectional network, 20 directory operation unit, 21 directory storage unit, 23
Counter, 24: update information generation unit, 25: directory storage unit, 26: transmission unit, 27: communication control unit, 30: reception unit, 31: communication control unit, 32
... Update operation unit, 33 ... Directory storage unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) G06F 15/401 340B 15/419 310 (72) Inventor Yoshihisa Gonno 6-7 Kita Shinagawa, Shinagawa-ku, Tokyo No. 35 Inside Sony Corporation (72) Kazuo Haraoka 6-7-35 Kita Shinagawa, Shinagawa-ku, Tokyo 6-35 Inside Sony Corporation (72) Kazuhiko Takabayashi 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo No. within Sony Corporation (72) Inventor Yasuaki Yamagishi 6-35 Kita Shinagawa, Shinagawa-ku, Tokyo F-term within Sony Corporation (reference) 5B045 BB04 BB47 DD16 5B075 KK03 KK24 KK33 KK40 ND35 PQ05 5B082 EA01 GA15 5B089 GA11 GA21 HA11 HA20 JA33 JB22 KA13 KC28 KE07

Claims (10)

[Claims] 1. A transmitting apparatus for transmitting directory data for managing the location of contents in a tree-structured data structure, comprising: a directory storage means configured to store directory data having a plurality of entries and having a tree-structured data structure. Directory operation means for updating the directory data stored in the directory storage means; update information generation means for generating update information representing the contents of the update of the directory data updated by the directory operation means; Transmission means for transmitting the update information generated by the update information generation means to the broadcast network, wherein each of the plurality of entries of the directory data stored in the directory storage means is directly below itself. Updates that change each time an update occurs Has a value of an operation, the update information generating means, transmitting system, wherein a value indicating the stage of the update has to include the above-mentioned update information generated above. 2. A transmission method for transmitting directory data for managing the location of contents in a tree-structured data structure, wherein directory data having a plurality of entries and having a tree-structured data structure is stored in a directory storage means. A step of directory operation for updating the directory data stored in the directory storage means; and an update information generation step of generating update information representing the contents of the update of the directory data updated by the directory operation step. And transmitting the update information generated in the update information generation step to a broadcast network. The transmission of the plurality of entries of the directory data stored in the directory storage means. Each has its own The update information generation step includes a value indicating an update stage that changes each time an update occurs below, and the update information generation step includes a value indicating the update stage in the generated update information. Transmission method characterized by the above-mentioned. 3. A receiving apparatus for receiving directory data for managing the location of contents in a tree-structured data structure, wherein the directory data is composed of a plurality of entries and has a tree-structured data structure. Directory storage means; reception means for receiving update information for updating the directory data stored in the directory storage means; storage in the directory storage means based on the contents of the update information received by the reception means Update operation means for updating the directory data to be updated, wherein each of the plurality of entries of the directory data stored in the directory storage means is updated when the update occurs immediately below itself. A first value indicating a stage, wherein the updating operation means includes: Comparing a second value indicating an update stage of the update information received by the receiving means with the first value, and when the first value and the second value match, A receiving apparatus for updating the directory data stored in the directory storage unit based on the update information received by the receiving unit. 4. The receiving apparatus according to claim 3, wherein the updating operation means determines that the first value and the second value are not matched when the result of the comparison indicates that the first value does not match the second value. The second value such that the second value matches the result of the comparison.
The update of the directory data stored in the directory storage unit based on the update information received by the reception unit is postponed until the update information having the value of is received by the reception unit. Receiving device. 5. The receiving apparatus according to claim 3, further comprising a bidirectional communication unit that performs bidirectional communication with a transmitting side that transmits the update information, wherein the update operation unit determines the result of the comparison. When the first value does not match the second value, the second value may be such that the first value matches the second value as a result of the comparison.
Waits for a predetermined period of time for the update information having the value of (i) to be received by the receiving means, and has the second value such that the first value and the second value match as a result of the comparison. If the update information is not received by the receiving means even after the predetermined period has elapsed, the update information has the second value such that the first value and the second value match as a result of the comparison. A receiving apparatus, wherein the update information is obtained through the two-way communication means. 6. A receiving method for receiving directory data that manages the location of contents in a tree-structured data structure, wherein the directory data including a plurality of entries and having a tree-structured data structure is stored in a directory. Means for storing the directory information stored in the directory storage means, receiving the update information for updating the directory data stored in the directory storage means, and the directory based on the content of the update information received in the receiving step An update operation of updating the directory data stored in the storage means, wherein each of the plurality of entries of the directory data stored in the directory storage means is updated every time an update occurs immediately below itself. To indicate the stage of the update Has a step of the update operation, it compares the second value and the first value indicating the stage of updating the update information received by the step of the reception has,
When the first value matches the second value, the directory data stored in the directory storage unit is updated based on the update information received in the receiving step. Receiving method. 7. A transmission / reception system for transmitting directory data for managing the location of contents in a tree-structured data structure and receiving the transmitted directory data, comprising a plurality of entries, and having a tree-structured data structure. First directory storage means for storing first directory data; and the first directory storage means stored in the first directory storage means.
Directory operation means for updating the directory data, update information generation means for generating update information representing the contents of the update of the first directory data updated by the directory operation means, and update information generation means for generating the update information. Transmitting means for transmitting the updated information to the broadcast network; second directory storing means for storing second directory data having a tree-structured data structure and including a plurality of entries; Receiving means for receiving the update information transmitted by the transmitting means to the broadcast network; and the second directory storage means based on the content of the update information received by the receiving means. Updating operation means for updating directory data, wherein the first directory The stored in the unit first
Each of the plurality of entries of the directory data has a first value indicating an update stage that changes each time an update occurs immediately below itself, and the update information generating unit determines the update stage. The first value shown is included in the generated update information, and the second value stored in the second directory storage means is included in the update information.
Each of the plurality of entries of the directory data has a second value indicating an update stage that changes each time an update occurs immediately below itself, and the update operation unit receives the update value by the reception unit. Comparing the first value and the second value of the update information, and when the first value and the second value match, the update information received by the receiving means. A transmission / reception system for updating the second directory data stored in the second directory storage means based on the following. 8. The transmission / reception system according to claim 7, wherein said updating operation means determines that said first value and said second value are not equal when said first value and said second value do not match as a result of said comparison. The first value such that the second value matches the result of the comparison.
The update of the second directory data stored in the second directory storage unit by the update information received by the reception unit is postponed until the update information having the value of is received by the reception unit. A transmission / reception system characterized in that: 9. The transmission / reception system according to claim 7, further comprising: a bidirectional communication unit configured to perform bidirectional communication between a transmission side that transmits the update information and a reception side that receives the transmitted update information. The update operation means further comprises: when the first value does not match the second value as a result of the comparison, the first value and the second value match each other as a result of the comparison. The first such as
Waits for a predetermined period of time for the update information having the value of (i) to be received by the receiving means, and has the first value such that the first value and the second value match as a result of the comparison. If the update information is not received by the receiving means even after the predetermined period has elapsed, the update information has the first value such that the first value and the second value match as a result of the comparison. A transmission / reception system, wherein the update information is obtained via the two-way communication means. 10. A transmission / reception method for transmitting directory data for managing the location of contents in a tree-structured data structure and receiving the transmitted directory data, comprising: a plurality of entries having a tree-structured data structure. Storing first directory data in first directory storage means; and storing the first directory data in the first directory storage means.
A directory operation step of updating the directory data of the above, an update information generation step of generating update information representing the contents of the update of the first directory data updated by the directory operation step, and the update information generation Transmitting the update information generated in step (b) to the broadcast network; and storing second directory data having a tree-structured data structure including a plurality of entries in a second directory storage means. Storing; receiving the update information transmitted to the broadcast network by the transmitting step; and receiving the update information from the second directory based on the content of the update information received by the receiving step. The second directory data stored in the storage means; And a step of updating operation for updating said first stored in the first directory storing means
Each of the plurality of entries of the directory data has a first value indicating an update stage that changes each time an update occurs immediately below itself, and the update information generation step includes the update stage. Is included in the generated update information, and the second value stored in the second directory storage means.
Each of the plurality of entries of the directory data has a second value indicating a stage of update, which changes each time an update occurs immediately below itself, and the step of the update operation includes the step of receiving Comparing the first value and the second value of the update information received by
When the first value matches the second value, the second directory data stored in the second directory storage unit is updated based on the update information received in the receiving step. Transmitting and receiving methods.