CN102780568B - The method of multicasting of data, device, terminal and system in a kind of unilateral network - Google Patents

Abstract

The present invention provides a method for multicasting data in a unidirectional network, a receiving method, a multicasting device, a receiving device and a system, wherein the method includes: generating the grouping bits corresponding to each grouping identifier according to the terminal equipment identifier included in each grouping identifier string; generate grouping information from the mapping relationship between each grouping identifier and the grouping bit string corresponding to each grouping identifier; broadcast the service metadata, the service description information corresponding to the service metadata, and the grouping information to the terminal device, and the The service description information includes the group identifiers of the service metadata that need to be broadcast. This solution does not need to broadcast all terminal device identifiers as group information to let each terminal device know the group it belongs to, greatly reducing the amount of data sent, saving bandwidth, and shortening the rotation cycle.

Description

Method, device, terminal and system for multicasting data in a unidirectional network

technical field

The invention relates to data multicasting, in particular to a data multicasting method, a receiving method, a multicasting device, a receiving device and a system in a unidirectional network.

Background technique

In a one-way digital TV network, if it is necessary to implement group delivery services, it is necessary to broadcast the group information to which each user belongs. The specific implementation method is as follows: assign a group ID to each group, and then assign the terminal Smart card number, device serial number) are assigned to this group, and finally all the group information is broadcast through the one-way network. When the end user receives the group information, it parses each group. If a group contains its own device identification , indicating that you belong to this group. Subsequently, the terminal device can receive the service data including the group ID.

Assuming a one-way digital TV network with 10 million terminal devices, and the identification of each terminal device is 32 characters, then it can be calculated that the size of the data to be broadcast is 10 million×32B=320 million B≈306MB. It can be seen that, The amount of data is relatively large. If the bandwidth allocated to the packet is only 8Mbps, it will take 306 seconds = 5 minutes to send 306MB. It can be seen that the bandwidth consumed is relatively large, and the rotation cycle is long.

Contents of the invention

In view of this, the object of the present invention is to provide a multicast method, a receiving method, a multicast device, a receiving device and a system for data in a one-way network, and it is not necessary to broadcast all terminal equipment identifiers as packet information to allow Each terminal device knows the group it belongs to, which greatly reduces the amount of data sent, saves bandwidth, and shortens the rotation cycle.

In order to achieve the above object, the technical solution of the present invention is specifically realized in the following way:

The invention provides a method for multicasting data in a unidirectional network, comprising:

Generate a group bit string corresponding to each group identification according to the terminal equipment identification contained in each group identification;

generating grouping information from the mapping relationship between each grouping identifier and the grouping bit string corresponding to each grouping identifier;

Broadcasting the service metadata, service description information corresponding to the service metadata, and the group information to the terminal device, where the service description information includes the group identifiers of the service metadata that need to be broadcast.

The present invention also provides a method for receiving data in a one-way network, including:

Obtaining grouping information from the broadcast data stream, parsing out each grouping identifier contained in the grouping information and a packet bit string corresponding to each grouping identifier;

Matching the terminal device identifier with each group bit string, if the match is successful, then saving the group identifier corresponding to the successfully matched group bit string;

Detect whether the service description information contains the group identifier, and if so, acquire service metadata corresponding to the service description information.

The present invention also provides a device for multicasting data in a unidirectional network, including:

A grouping bit string generating module, configured to generate a grouping bit string corresponding to each grouping identifier according to the terminal equipment identifier contained in each grouping identifier;

A grouping information generation module is used to generate grouping information with the mapping relationship of each grouping identifier and the corresponding grouping bit string of each grouping identifier;

The dissemination module is configured to broadcast service metadata, service description information corresponding to the service metadata, and the group information to the terminal device, where the service description information includes the identifiers of the groups whose service metadata needs to be broadcast.

The present invention also provides a device for receiving data in a one-way network, including:

The packet information parsing module is used to obtain the packet information from the broadcast data stream, and resolve each packet identifier contained in the packet information and the packet bit string corresponding to each packet identifier;

The group matching module is used to match the terminal device identification with each group bit string, and if the match is successful, then save the group identification corresponding to the successfully matched group bit string;

The data receiving module is configured to detect whether the group identifier is included in the service description information, and if so, obtain the service metadata corresponding to the service description information.

The present invention also provides a system for multicasting data in a unidirectional network, including:

a database, used to store identification information of the terminal device;

The group control server is used to read the identification information of the terminal equipment from the database to create a group, assign a group identification to each group, generate a group bit string corresponding to each group identification according to the terminal equipment identification contained in each group identification, and assign each The mapping relationship between the group identifier and the group bit string corresponding to each group identifier generates group information, sends each group identifier to the service server, and sends the group information to the broadcast server;

The service server generates service description information according to the service metadata and the group identifier, the service description information includes the group identifiers of the service metadata that need to be broadcast, and sends the service metadata and the service description information corresponding to the service metadata to broadcast server;

A broadcast server, configured to broadcast service metadata, service description information corresponding to the service metadata, and the grouping information to terminal devices;

The terminal device is configured to query the group identifier to which it belongs in the group information according to the terminal device identifier, detect whether the service description information contains the group identifier, and if so, obtain the service metadata corresponding to the service description information .

It can be seen from the above technical solution that by using multiple hash functions to map each terminal device identifier contained in the group identifier to a bit array to generate a group bit string, and then generate group information broadcast to the terminal by mapping the group bit string and the group identifier . The terminal device uses the same hash function to calculate the hash value sequence of the terminal device identifier, and matches the hash value sequence with each group bit string to obtain the group identifier to which the terminal device belongs. The terminal device receives the service data belonging to the group according to the group identifier. This solution does not need to broadcast all terminal device identifiers as group information to let each terminal device know the group it belongs to, greatly reducing the amount of data sent, saving bandwidth, and shortening the rotation cycle.

Description of drawings

Fig. 1 is a flow chart of a method for multicasting data in a unidirectional network provided by an embodiment of the present invention;

Fig. 2 is a flow chart of a method for generating a packet bit string provided by an embodiment of the present invention;

3 is a schematic diagram of a mapping method between a hash sequence value and a bit array provided by an embodiment of the present invention;

FIG. 4 is a flowchart of a method for receiving data in a one-way network provided by an embodiment of the present invention;

5 is a schematic diagram of a method for matching a hash sequence value of a terminal device and a packet bit string according to an embodiment of the present invention;

FIG. 6 is a structural diagram of a data multicast device in a unidirectional network provided by an embodiment of the present invention;

FIG. 7 is a structural diagram of a data receiving device in a one-way network provided by an embodiment of the present invention;

Fig. 8 is a system structure diagram of data multicast in a unidirectional network provided by an embodiment of the present invention.

detailed description

In order to make the object, technical solution, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and examples.

Figure 1 is a flow chart of a method for multicasting data in a unidirectional network provided by an embodiment of the present invention, including:

Step S101, generating a group bit string corresponding to each group identifier according to the terminal device identifier included in each group identifier.

The digital TV front-end system includes multiple service systems to provide various services for terminal equipment, such as an advertisement system, a video-on-demand system, and a weather forecast system. Each business system has different groups for users, and different groups receive different business data. Grouping users means grouping terminal device identifiers. The terminal device identifiers mentioned here may be terminal user names, IP addresses, CA card numbers, MAC addresses, device serial numbers, and other information that can uniquely identify terminal devices. When the system creates groups, it assigns a group ID to each group, and the service system provides different services to different groups according to the group ID.

Generating a group bit string corresponding to the group identifier according to the terminal device identifier included in the group identifier includes:

predefine a bit array and at least one hash function;

Obtain the terminal device identifier included in the group identifier;

Mapping the terminal device identifier included in the group identifier to the bit array through a hash function to generate a group bit string.

As shown in Figure 2, it is a flowchart of a method for generating a grouped bit string provided by an embodiment of the present invention, and Figure 3 is a schematic diagram of a mapping method between a hash sequence value and a bit array provided by an embodiment of the present invention, and the specific description is as follows:

Predefine an m-bit bit array and K different hash functions, where all bits of the bit array are initialized to 0, and the value ranges of the K hash functions are [0, m-1];

Read a terminal device identifier in the group, use K hash functions to perform hash calculation on the terminal device identifier, and generate a hash value sequence [H1, H2...Hk];

Set the bits corresponding to H1, H2...Hk in the bit array to 1;

Continue to read the next terminal device identifier and perform the same processing until all terminal device identifiers in the group are processed, and the finally generated bit array is the group bit string corresponding to the group.

Step S102, generating group information from the mapping relationship between each group identifier and the group bit string corresponding to each group identifier.

The group identifier is the unique identification symbol of a certain group, and the group bit string is the set of terminal equipment contained in a certain group. As mentioned above, the service system provides different services for different groups according to the group identification. In a one-way network, a terminal device cannot interact with the front-end system to know the group ID it belongs to. Therefore, the front-end system broadcasts group information and service information to each terminal device, and the terminal device matches its own terminal device ID with the group information. output the group ID to which it belongs, so as to receive the service corresponding to the group ID. The mapping relationship between the group identifier and the group bit string is used to generate group information, so that the terminal device can find the group identifier it belongs to according to the group information.

Step S103, broadcasting group information, service metadata, and service description information corresponding to the service metadata to the terminal device, wherein the service description information includes the identifiers of each group whose service metadata needs to be broadcast.

The service metadata, service description information corresponding to the service metadata, and grouping information can be broadcast to the terminal device together, or can be broadcast to the terminal device separately. The same service can be advertised to multiple different groups, therefore, there can be multiple group identifiers contained in the service description information. Generally, in the one-way data carousel, the broadcast cycle of service data is shorter than the broadcast cycle of group information.

Preferably, the version information corresponding to the grouping information can also be broadcast to the terminal device, so that the terminal device can judge whether the grouping information has changed according to the version information. The stored group identifier obtains business data once.

Implement the above-mentioned embodiment, by using multiple hash functions to map each terminal device identifier included in the group identifier to a bit array to generate a group bit string, and then broadcast the group information generated by the mapping relationship between the group bit string and the group identifier to the terminal, so that The terminal can find out which group it belongs to by matching the terminal device identifier with the group bit string. This solution does not need to broadcast all terminal device identifiers as group information to let each terminal device know the group it belongs to, greatly reducing the amount of data sent, saving bandwidth, and shortening the rotation cycle.

As shown in Figure 4, it is a flow chart of a method for receiving data in a one-way network provided by an embodiment of the present invention, and the method steps include:

In step S201, the grouping information is obtained from the broadcast data stream, and each grouping identifier included in the grouping information is parsed out and a packet bit string corresponding to each grouping identifier is obtained.

The terminal device obtains the grouping information in the broadcast data stream, and parses out each grouping identifier included in the grouping information and a packet bit string corresponding to each grouping identifier.

Preferably, when the broadcast data stream also includes version information corresponding to the grouping information, before step S201, it also includes: obtaining the version information corresponding to the grouping information from the broadcast data stream, and combining the version information with the version information stored in the terminal device Compare; if the same, then jump to step S203;

Otherwise, update the version information in the memory to the version information obtained from the broadcast data stream.

Step S202, matching the terminal device identifier with each group bit string, if the match is successful, storing the group identifier corresponding to the successfully matched group bit string.

Specifically, the hash value sequence corresponding to the terminal device identifier is matched with each group bit string, and if the match is successful, the group identifier corresponding to the successfully matched group bit string is stored.

As shown in Figure 5, it is a schematic diagram of a method for matching the hash sequence value of the terminal device and the packet bit string provided by the embodiment of the present invention, and the specific matching process is as follows:

First, obtain the terminal device identifier from the memory of the terminal device; secondly, use the same hash function as the front-end generated packet bit string to perform hash calculation on the terminal device to obtain the hash sequence value [H1, H2...Hk]; thirdly, read Take a group bit string, compare whether the corresponding H1, H2...Hk positions in the group bit string are 1, if all are 1, then the match is successful, the terminal device belongs to the group, and the group identifier is stored in the memory; Otherwise, the terminal device does not belong to the group, and continues to match with other group bit strings.

It should be noted that the step of calculating the hash value sequence of the terminal device can also be performed before obtaining the group information, and the calculated hash value sequence can also be stored to avoid repeated calculations in subsequent multiple matchings.

In actual use, the hash function has a certain probability of collision, and there may be exactly the same hash value sequence generated by two terminal device identifiers. This situation is called a false positive, that is, terminal devices that do not belong to this group also judge I belong to this group. By using multiple hash functions and increasing the length of the bit array, the false positive rate can be reduced. When the length of the bit array is 16 times the number of terminal devices in the group, and the number of hash functions is about 8, the false alarm rate can be reduced to below 0.0001, which basically meets most requirements.

Preferably, considering that the carousel period of the group information is longer than the carousel period of the service data, in order to provide real-time service data reception, the terminal device stores the successfully matched group identification in the memory, and when the group information does not change, The packet identification is directly read from the memory to receive service data. At the same time, the terminal device needs to monitor the version change of the group information in real time in the background. When the version information changes, it is necessary to re-match the hash value sequence of the terminal device with the group bit string of the new group information to obtain the updated group identification , saving it to memory.

In step S203, it is detected whether the group identifier is included in the service description information, and if yes, the service metadata corresponding to the service description information is acquired.

According to the group identifier, the terminal device detects whether the group identifier is included in the service description information, and if so, obtains corresponding service metadata through the service description information.

Implementing the above embodiment, by matching the hash value sequence of the terminal device identifier with the packet bit string in the group information in the broadcast data stream, the group identifier to which the terminal device belongs is obtained, and then the service data of the group is received according to the group identifier. In addition, by adding version information in the broadcast data stream, the terminal device does not need to repeat the matching, only when the packet information changes, the terminal device can receive the service data in a more real-time manner. This solution does not need to broadcast all terminal device identifiers as group information to let each terminal device know the group it belongs to, greatly reducing the amount of data sent, saving bandwidth, and shortening the rotation cycle.

As shown in Figure 6, it is a device structure diagram of a data multicast in a unidirectional network provided by an embodiment of the present invention, including:

The grouping bit string generation module 31 is used for generating the grouping bit string corresponding to each grouping identification according to the terminal device identification contained in each grouping identification;

The grouping information generation module 32 is used for generating grouping information with the mapping relationship of each grouping identifier and the grouping bit string corresponding to each grouping identifier;

The dissemination module 33 is configured to broadcast service metadata, service description information corresponding to the service metadata, and the group information to the terminal device, where the service description information includes the identifiers of the groups whose service metadata needs to be broadcast.

Wherein, the packet bit string generation module 31 includes:

A predefined module 311, configured to predefine a bit array and at least one hash function;

A terminal identification acquisition module 312, configured to acquire the terminal equipment identification contained in the group identification;

The group bit string generation sub-module 313 is configured to map the terminal device identifier contained in the group identifier to the bit array through the hash function to generate a group bit string.

The dissemination module 33 is further configured to broadcast the version information corresponding to the group information to the terminal device.

Implement the above-mentioned embodiment, by using multiple hash functions to map each terminal device identifier included in the group identifier to a bit array to generate a group bit string, and then broadcast the group information generated by the mapping relationship between the group bit string and the group identifier to the terminal, so that The terminal can find out which group it belongs to by matching the terminal device identifier with the group bit string. This solution does not need to broadcast all terminal device identifiers as group information to let each terminal device know the group it belongs to, greatly reducing the amount of data sent, saving bandwidth, and shortening the rotation cycle.

As shown in FIG. 7, it is a structural diagram of a device for receiving data in a one-way network provided by an embodiment of the present invention, including:

The grouping information parsing module 41 is used for obtaining the grouping information from the broadcast data stream, and parsing out each grouping identifier and the grouping bit string corresponding to each grouping identifier;

The group matching module 42 is used to match the terminal device identification with each group bit string, if the match is successful, then save the group identification corresponding to the successfully matched group bit string;

The data receiving module 43 is configured to detect whether the group identifier is included in the service description information, and if yes, obtain the service metadata corresponding to the service description information.

Wherein, group matching module 42 comprises:

Calculation module 421, used to calculate the hash value sequence of terminal device identification;

The matching sub-module 422 is configured to match the hash value sequence with each group bit string, and if the match is successful, save the group identifier corresponding to the successfully matched group bit string.

Preferably, the device further includes a version comparison module (not shown in the figure), configured to obtain version information corresponding to the packet information from the broadcast data stream, and compare the version information with the version information saved by the terminal device, If they are different, update the version information in the memory to the version information obtained from the broadcast data stream, and trigger the group information parsing module 41 and the group matching module 42 to reacquire the version information that matches the terminal device from the broadcast data stream. After the group identification, the data receiving module 43 obtains the corresponding service metadata according to the re-acquired group identification;

Otherwise, the trigger data receiving module 43 acquires corresponding service metadata according to the stored group identifier.

Implementing the above embodiment, by matching the hash value sequence of the terminal device identifier with the packet bit string in the group information in the broadcast data stream, the group identifier to which the terminal device belongs is obtained, and then the service data of the group is received according to the group identifier. In addition, by adding version information in the broadcast data stream, the terminal device does not need to repeat the matching, only when the packet information changes, the terminal device can receive the service data in a more real-time manner. This solution does not need to broadcast all terminal device identifiers as group information to let each terminal device know the group it belongs to, greatly reducing the amount of data sent, saving bandwidth, and shortening the rotation cycle.

As shown in FIG. 8, it is a system structure diagram of data multicast in a unidirectional network provided by an embodiment of the present invention, including:

A database 51, configured to store identification information of terminal equipment;

The group control server 52 is used to read the identification information of the terminal equipment from the database to create a group, assign a group identification to each group, generate a group bit string corresponding to each group identification according to the terminal equipment identification contained in each group identification, and The mapping relationship between each group identifier and the group bit string corresponding to each group identifier generates group information, sends each group identifier to the service server, and sends the group information to the broadcast server;

The service server 54 generates service description information according to the service metadata and group identifiers, the service description information includes the group identifiers that the service metadata needs to broadcast, and sends the service metadata and the service description information corresponding to the service metadata To broadcast server;

The broadcast server 53 is configured to broadcast service metadata, service description information corresponding to the service metadata, and the group information to the terminal device;

The terminal device 55 is configured to query the group identifier to which it belongs in the group information according to the terminal device identifier, detect whether the service description information contains the group identifier, and if so, obtain the service element corresponding to the service description information data.

Implementing the above embodiment, by using a plurality of hash functions to map each terminal device identifier contained in the group identifier to a bit array to generate a group bit string, and then broadcast the group information generated by the mapping relationship between the group bit string and the group identifier to the terminal. The terminal device uses the same hash function to calculate the hash value sequence of the terminal device identifier, and matches the hash value sequence with each group bit string to obtain the group identifier to which the terminal device belongs. The terminal device receives the service data belonging to the group according to the group identifier. This solution does not need to broadcast all terminal device identifiers as group information to let each terminal device know the group it belongs to, greatly reducing the amount of data sent, saving bandwidth, and shortening the rotation cycle.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection.

Claims (9)

1. the method for multicasting of data in unilateral network, is characterized in that, comprising:

Grouping bit string corresponding to each group character is generated according to the Terminal Equipment Identifier that each group character comprises;

The mapping relations of each group character and grouping bit string corresponding to each group character are generated grouping information;

Version information corresponding to service metadata, the business description information corresponding with described service metadata, described grouping information and described grouping information is broadcast to terminal equipment, judge whether grouping information changes to make described terminal equipment according to described version information, if do not changed, then do not resolve the grouping information in broadcast data stream, the group character directly stored according to the last time obtains business datum; Described business description packets of information needs each group character of broadcast containing described service metadata.

2. the method for claim 1, is characterized in that, the grouping bit string that the Terminal Equipment Identifier comprised according to group character generates group character corresponding comprises:

A pre-defined units group and at least one hash function;

Obtain the Terminal Equipment Identifier that group character comprises;

By described hash function, the Terminal Equipment Identifier that described group character comprises is mapped to described bit array and generates grouping bit string.

3. the method for reseptance of data in unilateral network, is characterized in that, comprising:

From broadcast data stream, obtain the version information that grouping information is corresponding, the version information that described version information and terminal equipment are preserved is compared; If identical, then jump to and detect in business description information whether comprise described group character, if comprise, then obtain the step of service metadata corresponding to described business description information; If otherwise different, then the version information in memory is updated to the described version information obtained from broadcast data stream;

From broadcast data stream, obtain grouping information, parse the grouping bit string that each group character that grouping information comprises is corresponding with each group character;

Terminal Equipment Identifier is mated with each grouping bit string, if the match is successful, then the group character that the preservation grouping bit string that the match is successful is corresponding;

Detect in business description information and whether comprise described group character, if comprise, then obtain the service metadata that described business description information is corresponding.

4. method as claimed in claim 3, is characterized in that, is describedly mated with each grouping bit string by Terminal Equipment Identifier, if the match is successful, then the group character that the preservation grouping bit string that the match is successful is corresponding comprises:

Sequence of hash values corresponding for Terminal Equipment Identifier is mated with each grouping bit string, if the match is successful, then the group character that the preservation grouping bit string that the match is successful is corresponding.

5. the device of data multicast in unilateral network, is characterized in that, comprising:

Grouping bit string generation module, the Terminal Equipment Identifier for comprising according to each group character generates grouping bit string corresponding to each group character;

Grouping information generation module, for generating grouping information by the mapping relations of each group character and grouping bit string corresponding to each group character;

Broadcast module, for version information corresponding to service metadata, the business description information corresponding with described service metadata, described grouping information and grouping information is broadcast to terminal equipment, judge whether grouping information changes to make described terminal equipment according to described version information, if do not changed, then do not resolve the grouping information in broadcast data stream, the group character directly stored according to the last time obtains business datum; Described business description packets of information needs each group character of broadcast containing described service metadata.

6. device as claimed in claim 5, it is characterized in that, described grouping bit string generation module comprises:

Predefine module, for a pre-defined units group and at least one hash function;

Terminal iidentification acquisition module, for obtaining the Terminal Equipment Identifier that group character comprises;

Grouping bit string generates submodule, generates grouping bit string for the Terminal Equipment Identifier that described group character comprises being mapped to described bit array by described hash function.

7. the device of data receiver in unilateral network, is characterized in that, comprising:

Grouping information parsing module, for obtaining grouping information from broadcast data stream, parses the grouping bit string that each group character that grouping information comprises is corresponding with each group character;

Group match module, for Terminal Equipment Identifier is mated with each grouping bit string, if the match is successful, then the group character that the preservation grouping bit string that the match is successful is corresponding;

Data reception module, for detecting in business description information whether comprise described group character, if comprise, then obtains the service metadata that described business description information is corresponding;

Edition comparison module, for obtaining version information corresponding to grouping information from broadcast data stream, the version information that described version information and terminal equipment are preserved is compared, if different, then the version information in memory is updated to the described version information obtained from broadcast data stream, and triggers described grouping information parsing module and described group match module and again obtain from broadcast data stream and obtain corresponding service metadata by described data reception module according to the described group character again obtained again with after the group character that described terminal equipment mates; If otherwise identical, then trigger data receiver module obtains corresponding service metadata according to the group character stored.

8. device as claimed in claim 7, it is characterized in that, described group match module comprises:

Computing module, for the sequence of hash values of computing terminal device identification;

Matched sub-block, for described sequence of hash values is mated with each grouping bit string, if the match is successful, then the group character that the preservation grouping bit string that the match is successful is corresponding.

9. the system of data multicast in unilateral network, is characterized in that, comprising:

Database, for the identification information of storage terminal equipment;

Grouping Control Server, identification information for reading terminal equipment from described database creates grouping, for each grouping allocation packets mark, grouping bit string corresponding to each group character is generated according to the Terminal Equipment Identifier that each group character comprises, the mapping relations of each group character and grouping bit string corresponding to each group character are generated grouping information, each group character is sent to service server, grouping information is sent to and broadcasts server;

Service server, business description information is generated according to service metadata and group character, described business description packets of information needs each group character of broadcast containing described service metadata, service metadata and business description information corresponding to described service metadata is sent to and broadcasts server;

Broadcast server, for version information corresponding to service metadata, the business description information corresponding with described service metadata, described grouping information and described grouping information is broadcast to terminal equipment;

Terminal equipment, for inquiring the group character belonging to it in described grouping information according to Terminal Equipment Identifier, detects in business description information whether comprise described group character, if comprise, then obtains the service metadata that described business description information is corresponding; Described terminal equipment, also for judging whether grouping information changes according to described version information, if do not changed, is not then resolved the grouping information in broadcast data stream, and the group character directly stored according to the last time obtains business datum.