CN108900427A - Digital content delivery system - Google Patents

Abstract

The present invention provides a digital content delivery system, comprising: a storage unit for storing digital content to be delivered; a processing unit connected with the storage unit and a communication unit for transferring the digital content stored in the storage unit through The communication unit sends to the user unit; the communication unit is used for communication between the processing unit and the user unit; the user unit includes a communication device and a content display device, which is used to receive and display the digital content sent by the processing unit; the processing unit communicates The unit communicates with the user unit, detects the downlink rate of the user unit, and when the downlink rate is higher than the first preset value, the processing unit reads the digital content in the storage unit and sends the digital content to the user through the communication unit unit.

Description

Digital Content Delivery System

technical field

The invention relates to the field of communication technology, in particular to a digital content delivery system.

Background technique

Today's digital content, including audio, video and other multimedia files, when encountering a user with a bad signal, pushing digital content often occupies the user's bandwidth, seriously affecting the user's reception of other information, such as causing download interruptions, etc. When encountering When it comes to an emergency, it also makes it difficult for users to receive important information in time. The current solution is to limit the downlink speed of a single user, but for users in places with weaker signals, the bandwidth will still be fully occupied.

Contents of the invention

In order to solve this problem, the present application provides a digital content delivery system, which can push digital content according to the user's network conditions and avoid congestion of the user's communication network. A digital content delivery system provided by the application includes:

a storage unit for storing the digital content to be delivered;

The processing unit is connected with the storage unit and the communication unit, and is used to send the digital content stored in the storage unit to the user unit through the communication unit;

a communication unit for communication between the processing unit and the user unit;

The user unit, including a communication device and a content display device, is used to receive and display the digital content sent by the processing unit;

The processing unit communicates with the user unit through the communication unit, detects the downlink rate of the user unit, and when the downlink rate is higher than the first preset value, the processing unit reads the digital content in the storage unit and passes the digital content through the communication unit delivered to the user unit.

preferred,

The subscriber unit also includes a feedback device, the feedback device is used for:

Feedback to the processing unit the time taken for the user unit to fully receive the delivered content;

Feedback the network type used by the user unit to the processing unit;

Feedback the current location of the user unit to the processing unit;

The processing unit compares the time taken by the user unit to fully receive the delivered content with the average time taken by all user units to fully receive the delivered content, and when the ratio between the two is greater than a second preset value, determine the network status of the user unit unstable;

The processing unit acquires the network types and locations of all subscriber units whose line rate is not higher than the first preset value and whose network status is unstable within the first preset time interval, and sets the location as the first location;

For each network type, the processing unit uses the first position as a sample point to perform cluster analysis to obtain multiple clusters;

For each cluster, the processing unit removes sample points whose sample point density is lower than a third preset value to obtain a new cluster;

For each new cluster, the processing unit obtains the envelope of its sample points, and performs morphological filtering on the envelope to obtain a new area;

The processing unit sets the new area as a weak signal area within the first preset time interval, and sets other areas as strong signal areas within the first preset time interval;

The processing unit obtains the weather information of each new area on the Internet within the first preset time interval through the communication unit;

The processing unit acquires the user density of each new area on the Internet within the first preset time interval through the communication unit;

The processing unit detects the influence of weather changes and/or user density changes on weak signal areas, and when a weak signal area becomes a strong signal area as the weather changes and/or user density changes, the area is marked as a signal change Area, record the weather change and/or user density change at this time, as the signal weak-strong change condition of the area, when the weather changes and/or user density changes, a weak signal area is always a weak signal area , marking the area as a stable weak signal area;

When the digital content needs to be pushed, the processing unit: pushes the digital content to the user unit located in the strong signal area; obtains the weather information and/or user density information of the variable signal area, when the weather information and/or user density reach the When the weak-to-strong signal change condition in the signal-changing area, push the digital content to the subscriber unit located in the signal-changing area.

preferred,

The storage unit also stores sender information of the digital content and receiver information of the digital content;

The numbers include displaying in one or more forms of image, video, and audio;

The subscriber unit includes a subscriber unit identification;

The recipient information includes: a subscriber unit with a specified identifier; and/or, a subscriber unit located in a specified area; and/or, a subscriber unit located in a specified area at a specified time;

When the digital content needs to be pushed, the processing unit pushes the digital content to the user unit which satisfies the information of the recipient and is located in a strong signal area; Subscriber units in the variable signal area of the signal weak-strong change condition perform digital content push.

Preferably, the system also includes:

The content acquisition unit is connected with the storage unit, and is used to obtain the digital content to be delivered from the digital content provider, and write it into the storage unit;

The storage management unit is connected with the storage unit and is used to manage the digital content in the storage unit, the sender information of the digital content and the receiver information of the digital content, specifically including:

Check the integrity of the information, including checking whether each piece of digital content has corresponding sender information and receiver information;

When the information is incomplete, supplement the information to make it complete or delete the digital content with incomplete information according to the preset rules;

Prioritize the digital content, the priority includes at least 2 levels, and write the identification of the digital content with a priority higher than the preset level into the priority file, and the processing unit casts the digital content according to the priority file. Send to sort and deliver.

Preferably, the processing unit sorts and delivers the delivery of digital content according to the priority file, specifically:

The processing unit obtains the priority of the digital content identifier in the priority file;

The processing unit retrieves the priority in the priority file, and when there is a digital content ID with the highest priority, the processing unit identifies the digital content with the highest priority according to the writing time of the digital content ID with the highest priority in the priority file Sort as the highest priority queue;

For digital content identifications that are not of the highest priority, the processing unit sets a selection coefficient for each priority;

For the digital content identifiers of each priority that is not the highest priority, the processing unit divides them into segments according to the order of writing time, except that the number of the last segment is not higher than the selection coefficient, and the number of each segment is equal to the selection coefficient;

Label each piece of digital content of each priority that is not the highest priority, specifically, each piece of digital content of each priority is identified as an arithmetic sequence, and the tolerance is the number of priorities after the highest priority is removed Add 1, the first item is the priority number of the priority after removing the highest priority;

The processing unit arranges each piece of digital content identification according to its label from small to large to form a common queue;

The processing unit connects the normal queue to the end of the highest priority queue to form a delivery sequence;

The processing unit searches for the digital content corresponding to the digital content identifier, the sender information of the digital content, and the receiver information of the digital content according to the order of the delivery sequence, and delivers the found digital content according to the receiver information of the digital content , and feed back the delivery result to the sender of the digital content.

preferred,

When the priority of the delivered digital content is the highest priority, the processing unit delivers the found digital content according to the receiver information of the digital content;

When the priority of the delivered digital content is not the highest priority, the processing unit pushes the digital content to the user unit that simultaneously satisfies the recipient information and is located in a strong signal area; And/or the user units in the signal-changing area whose user density reaches the signal-weak-to-strong change condition of the signal-changing area perform digital content push.

preferred,

The storage unit also stores sender information of the digital content;

The user unit further includes a feedback device, the feedback device is used to feed back the time when the user unit displays and delivers the content to the processing unit;

For each digital content, the processing unit calculates a first ratio between the time during which the user unit presents the digital content and the time during which the digital content itself is played;

The processing unit counts a second ratio between the number of subscriber units whose first ratio is less than a fourth preset value and the number of subscriber units whose first ratio is not less than a fourth preset value, when the second ratio is greater than a fifth preset When setting the value, the processing unit feeds back the second ratio to the sender of the digital content, and lowers the priority of the digital content.

The digital content delivery system provided by the present invention can select and push digital content according to the user's network conditions, so as to avoid congestion of the user's communication network.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, and are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention. In the attached picture:

FIG. 1 is a schematic structural diagram of a digital content delivery system in an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a digital content delivery system in another embodiment of the present invention.

Detailed ways

The preferred embodiments of the present invention will be described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

Please refer to Figure 1, the present application provides a digital content delivery system, including:

a storage unit for storing the digital content to be delivered;

The processing unit is connected with the storage unit and the communication unit, and is used to send the digital content stored in the storage unit to the user unit through the communication unit;

a communication unit for communication between the processing unit and the user unit;

User units (such as mobile phones, tablet computers, smart watches, etc.), including communication devices and content display devices (display screens, speakers, etc.), are used to receive and display digital content sent by the processing unit;

The processing unit communicates with the user unit through the communication unit, detects the downlink rate of the user unit, and when the downlink rate is higher than the first preset value, the processing unit reads the digital content in the storage unit and passes the digital content through the communication unit delivered to the user unit.

The invention judges the user's network situation by detecting the downlink rate of the user unit, and then selects and pushes digital content according to the user's network situation, so as to avoid congestion of the user's communication network.

Since the detection of the downlink rate of the subscriber unit is often affected by the current network operation status of the user, the high downlink rate of the subscriber unit does not guarantee that the user's network can maintain this high downlink rate for a long time. Correspondingly, for the network Especially for wireless networks, the signal is often relatively stable, so it is possible to decide whether to push digital content to the user by judging whether the user is located in an area with a good signal. strength, it is not necessary to perform a network test for each user, which can further reduce the occupation of network bandwidth. In one embodiment of the present invention,

The subscriber unit also includes a feedback device, the feedback device is used for:

Feedback to the processing unit the time taken for the user unit to fully receive the delivered content;

Feedback the network type used by the user unit to the processing unit;

Feedback the current location of the user unit to the processing unit;

The processing unit compares the time taken by the user unit to completely receive the delivered content with the average time taken by all user units to fully receive the delivered content, and when the ratio between the two is greater than a second preset value (the second preset value is greater than 1, generally When it is set between 2-10, preferably between 3-5), it is determined that the network status of the subscriber unit is unstable;

The processing unit obtains the first preset time interval (the length of this time interval is generally 1-2 hours, if the time is too low, the effective samples will be too few, and if the time is too long, the data accuracy will be low). The network type and location of the subscriber unit that is higher than the first preset value and the network state is unstable, and the location is set as the first location;

For each network type, the processing unit uses the first position as a sample point to perform cluster analysis to obtain multiple clusters (by this method, regions can be automatically divided according to the strength of the signal, rather than according to administrative divisions, etc. The division method with inconsistent signal strength is more convenient to push digital content to a certain area according to the signal strength. Different network types may have different performances in the same area, so the obtained multiple clusters or areas are actually Corresponding to a network type, for example, China Unicom uses the classification of one cluster, and China Mobile uses the classification of another cluster. Different network types need to be processed separately. For example, first process the data of China Unicom separately, and then process the data of mobile after completion, and then Telecom data, the following processing is for data of the same network type);

For each cluster, the processing unit removes the sample points whose sample point density is lower than the third preset value to obtain a new cluster (by this processing method, it can be achieved without considering the use of push settings in sparsely populated areas, reducing The amount of calculation can also solve the false samples of individual positioning offsets to sparsely populated areas, because such offsets are rare, so they can be filtered out by setting the density);

For each new cluster, the processing unit obtains the envelope of its sample points, and performs morphological filtering on the envelope (including dilation, opening and closing operations to remove abnormalities and a small number of isolated samples in positioning recognition) , get the new area;

The processing unit sets the new area as a weak signal area in the first preset time interval, and sets other areas as strong signal areas in the first preset time interval (using signal strength to partition to realize pushing digital content management, to avoid pushing digital content in weak signal areas and causing users’ network communications to be seriously affected);

The processing unit obtains the weather information of each new area on the Internet within the first preset time interval through the communication unit;

The processing unit acquires the user density of each new area on the Internet within the first preset time interval through the communication unit;

The processing unit detects the influence of weather changes and/or user density changes on weak signal areas, and when a weak signal area becomes a strong signal area as the weather changes and/or user density changes, the area is marked as a signal change Area, record the weather changes and/or user density changes at this time, as the signal weak-strong change conditions in this area (because some weather conditions will have a significant impact on the user's network conditions, and at the same time, some activities that cause a large number of people to gather will also As a result, the network conditions of users near the aggregation area change. In order to avoid misidentification in this situation, it is necessary to mark these areas and the conditions of the network change, so as to avoid pushing digital content to users with weak signal or not to push digital content to users with strong signal ), when a weak signal area is always a weak signal area when the weather changes and/or the user density changes, the area is marked as a stable weak signal area;

When the digital content needs to be pushed, the processing unit: pushes the digital content to the user unit located in the strong signal area; obtains the weather information and/or user density information of the variable signal area, when the weather information and/or user density reach the When the weak-to-strong signal change condition in the signal-changing area, push the digital content to the subscriber unit located in the signal-changing area.

Through this processing method, the calculation amount of automatic signal area division can be reduced, the influence of noise data can be avoided, and the stability of signal strength area division can be improved.

In order to adapt to the push of digital content to users in areas where the signal strength will change, and to avoid pushing digital content to irrelevant people, resulting in excessive bandwidth occupation, in an embodiment of the present invention,

The storage unit also stores sender information of the digital content and receiver information of the digital content;

The numbers include displaying in one or more forms of image, video, and audio;

The subscriber unit includes a subscriber unit identification;

The recipient information includes: a subscriber unit with a specified identifier; and/or, a subscriber unit located in a specified area; and/or, a subscriber unit located in a specified area at a specified time;

When the digital content needs to be pushed, the processing unit pushes the digital content to the user unit which satisfies the information of the recipient and is located in a strong signal area; Subscriber units in the variable signal area of the signal weak-strong change condition perform digital content push.

Because it may be necessary to push more important content, while some digital content is not so important, and important content needs to be pushed first, in order to identify the importance of digital content, in an embodiment of the present invention, as shown in Figure 2, is A schematic structural diagram of a digital content delivery system in another embodiment of the present invention, the system further includes:

The content acquisition unit is connected with the storage unit, and is used to obtain the digital content that needs to be delivered from the delivery party of the digital content, and write it into the storage unit (different delivery parties can set different permissions, such as government agencies can set The highest delivery authority, while commercial organizations cannot set the highest authority);

The storage management unit is connected with the storage unit and is used to manage the digital content in the storage unit, the sender information of the digital content and the receiver information of the digital content, specifically including:

Check the integrity of the information, including checking whether each piece of digital content has corresponding sender information and receiver information;

When the information is incomplete, supplement the information according to the preset rules to make it complete (when the sender information is missing, retrieve the sender information according to the source IP of the digital content, and when the unique sender is retrieved, it will retrieve The information of the only sending party received is set as the sending party information) or delete the digital content with incomplete information (when the information cannot be supplemented to make it complete, delete the digital content with incomplete information);

Prioritize the digital content, the priority includes at least 2 levels, and write the identification of the digital content with a priority higher than the preset level into the priority file, and the processing unit casts the digital content according to the priority file. Send to sort and deliver.

Through this method, the push order of digital content can be controlled, so that important content is pushed first, and the stability of digital content push is ensured.

In order to push digital content of different levels in an orderly manner and ensure that digital content of each level can be pushed to, in an embodiment of the present invention, the processing unit performs delivery of digital content according to the priority file Sort and deliver, specifically:

The processing unit obtains the priority of the digital content identifier in the priority file;

The processing unit retrieves the priority in the priority file, and when there is a digital content ID with the highest priority (generally digital content for emergency rescue), the processing unit writes according to the digital content ID with the highest priority in the priority file Sort the highest priority digital content identifiers in order of time as the highest priority queue (ensure that emergency rescue and other digital content with the highest priority are pushed first);

For digital content identifications that are not of the highest priority, the processing unit sets a selection coefficient for each priority;

For the digital content identifiers of each priority that is not the highest priority, the processing unit divides them into segments according to the order of writing time, except that the number of the last segment is not higher than the selection coefficient, and the number of each segment is equal to the selection coefficient;

Label each piece of digital content of each priority that is not the highest priority, specifically, each piece of digital content of each priority is identified as an arithmetic sequence, and the tolerance is the number of priorities after the highest priority is removed Add 1, the first item is the priority number of the priority after removing the highest priority;

The processing unit arranges each piece of digital content identification according to its label from small to large to form a common queue;

The processing unit connects the normal queue to the end of the highest priority queue to form a delivery sequence;

The processing unit searches for the digital content corresponding to the digital content identifier, the sender information of the digital content, and the receiver information of the digital content according to the order of the delivery sequence, and delivers the found digital content according to the receiver information of the digital content , and feed back the delivery result to the sender of the digital content.

Through this method, it can be guaranteed that even if the digital content of high priority (except for the highest priority, the digital content of the highest priority will not continue to increase) continues to increase, the content of low priority can be pushed to the user unit, avoiding The situation where low-priority digital content has been queued and cannot be pushed, while ensuring that digital content of different priorities written at a similar time will give priority to pushing high-priority digital content.

In order to have the highest priority for emergency rescue, etc., it can be sent to the user unit in time, in one embodiment of the present invention,

When the priority of the delivered digital content is the highest priority, the processing unit delivers the found digital content according to the receiver information of the digital content;

When the priority of the delivered digital content is not the highest priority, the processing unit pushes the digital content to the user unit that simultaneously satisfies the recipient information and is located in a strong signal area; And/or the user units in the signal-changing area whose user density reaches the signal-weak-to-strong change condition of the signal-changing area perform digital content push.

Through the implementation of the present invention, digital content with the highest priority, such as emergency rescue, is directly pushed without considering the user's network status, so as to achieve the purpose of emergency rescue and the like.

Because the sender of digital content sometimes needs to evaluate the digital content delivered, and most users skip the digital content they don’t like directly and have no motivation to rate it, so it is easy to use ratings to evaluate digital content Systematic errors, in order to avoid the occurrence of this situation, and reduce the number of times users receive disliked digital content, in one embodiment of the present invention,

The storage unit also stores sender information of the digital content;

The user unit further includes a feedback device, the feedback device is used to feed back the time when the user unit displays and delivers the content to the processing unit;

For each digital content, the processing unit calculates a first ratio between the time during which the user unit presents the digital content and the time during which the digital content itself is played;

The processing unit counts a second ratio between the number of subscriber units whose first ratio is less than a fourth preset value and the number of subscriber units whose first ratio is not less than a fourth preset value, when the second ratio is greater than a fifth preset When setting the value, the processing unit feeds back the second ratio to the sender of the digital content, and lowers the priority of the digital content.

The digital content delivery system provided by the present invention can select and push digital content according to the user's network conditions, so as to avoid congestion of the user's communication network.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (7)

1. A digital content delivery system, characterized in that, comprising: a storage unit for storing the digital content to be delivered; The processing unit is connected with the storage unit and the communication unit, and is used to send the digital content stored in the storage unit to the user unit through the communication unit; a communication unit for communication between the processing unit and the user unit; The user unit, including a communication device and a content display device, is used to receive and display the digital content sent by the processing unit; The processing unit communicates with the user unit through the communication unit, detects the downlink rate of the user unit, and when the downlink rate is higher than the first preset value, the processing unit reads the digital content in the storage unit and passes the digital content through the communication unit delivered to the user unit. 2. The system of claim 1, wherein: The subscriber unit also includes a feedback device, the feedback device is used for: Feedback to the processing unit the time taken for the user unit to fully receive the delivered content; Feedback the network type used by the user unit to the processing unit; Feedback the current location of the user unit to the processing unit; The processing unit compares the time taken by the user unit to fully receive the delivered content with the average time taken by all user units to fully receive the delivered content, and when the ratio between the two is greater than a second preset value, determine the network status of the user unit unstable; The processing unit acquires the network types and locations of all subscriber units whose line rate is not higher than the first preset value and whose network status is unstable within the first preset time interval, and sets the location as the first location; For each network type, the processing unit uses the first position as a sample point to perform cluster analysis to obtain multiple clusters; For each cluster, the processing unit removes sample points whose sample point density is lower than a third preset value to obtain a new cluster; For each new cluster, the processing unit obtains the envelope of its sample points, and performs morphological filtering on the envelope to obtain a new area; The processing unit sets the new area as a weak signal area within the first preset time interval, and sets other areas as strong signal areas within the first preset time interval; The processing unit obtains the weather information of each new area on the Internet within the first preset time interval through the communication unit; The processing unit acquires the user density of each new area on the Internet within the first preset time interval through the communication unit; The processing unit detects the influence of weather changes and/or user density changes on weak signal areas, and when a weak signal area becomes a strong signal area as the weather changes and/or user density changes, the area is marked as a signal change Area, record the weather change and/or user density change at this time, as the signal weak-strong change condition of the area, when the weather changes and/or user density changes, a weak signal area is always a weak signal area , marking the area as a stable weak signal area; When the digital content needs to be pushed, the processing unit: pushes the digital content to the user unit located in the strong signal area; obtains the weather information and/or user density information of the variable signal area, when the weather information and/or user density reach the When the weak-to-strong signal change condition in the signal-changing area, push the digital content to the subscriber unit located in the signal-changing area. 3. The system of claim 2, wherein: The storage unit also stores sender information of the digital content and receiver information of the digital content; The numbers include displaying in one or more forms of image, video, and audio; The subscriber unit includes a subscriber unit identification; The recipient information includes: a subscriber unit with a specified identifier; and/or, a subscriber unit located in a specified area; and/or, a subscriber unit located in a specified area at a specified time; When the digital content needs to be pushed, the processing unit pushes the digital content to the user unit which satisfies the information of the recipient and is located in a strong signal area; Subscriber units in the variable signal area of the signal weak-strong change condition perform digital content push. 4. The system according to claim 1, further comprising: The content acquisition unit is connected with the storage unit, and is used to obtain the digital content to be delivered from the digital content provider, and write it into the storage unit; The storage management unit is connected with the storage unit and is used to manage the digital content in the storage unit, the sender information of the digital content and the receiver information of the digital content, specifically including: Check the integrity of the information, including checking whether each piece of digital content has corresponding sender information and receiver information; When the information is incomplete, supplement the information to make it complete or delete the digital content with incomplete information according to the preset rules; Prioritize the digital content, the priority includes at least 2 levels, and write the identification of the digital content with a priority higher than the preset level into the priority file, and the processing unit casts the digital content according to the priority file. Send to sort and deliver. 5. The system according to claim 4, wherein the processing unit sorts and delivers the delivery of digital content according to the priority file, specifically: The processing unit obtains the priority of the digital content identifier in the priority file; The processing unit retrieves the priority in the priority file, and when there is a digital content ID with the highest priority, the processing unit identifies the digital content with the highest priority according to the writing time of the digital content ID with the highest priority in the priority file Sort as the highest priority queue; For digital content identifications that are not of the highest priority, the processing unit sets a selection coefficient for each priority; For the digital content identifiers of each priority that is not the highest priority, the processing unit divides them into segments according to the order of writing time, except that the number of the last segment is not higher than the selection coefficient, and the number of each segment is equal to the selection coefficient; Label each piece of digital content of each priority that is not the highest priority, specifically, each piece of digital content of each priority is identified as an arithmetic sequence, and the tolerance is the number of priorities after the highest priority is removed Add 1, the first item is the priority number of the priority after removing the highest priority; The processing unit arranges each piece of digital content identification according to its label from small to large to form a common queue; The processing unit connects the normal queue to the end of the highest priority queue to form a delivery sequence; The processing unit searches for the digital content corresponding to the digital content identifier, the sender information of the digital content, and the receiver information of the digital content according to the order of the delivery sequence, and delivers the found digital content according to the receiver information of the digital content , and feed back the delivery result to the sender of the digital content. 6. The system according to claim 2 or 5, characterized in that, When the priority of the delivered digital content is the highest priority, the processing unit delivers the found digital content according to the receiver information of the digital content; When the priority of the delivered digital content is not the highest priority, the processing unit pushes the digital content to the user unit that simultaneously satisfies the recipient information and is located in a strong signal area; And/or the user units in the signal-changing area whose user density reaches the signal-weak-to-strong change condition of the signal-changing area perform digital content push. 7. The system of claim 4, wherein: The storage unit also stores sender information of the digital content; The user unit also includes a feedback device, the feedback device is used to feed back the time when the user unit displays and delivers the content to the processing unit; For each digital content, the processing unit calculates a first ratio between the time during which the user unit presents the digital content and the time during which the digital content itself is played; The processing unit counts a second ratio between the number of subscriber units whose first ratio is less than a fourth preset value and the number of subscriber units whose first ratio is not less than a fourth preset value, when the second ratio is greater than a fifth preset When setting the value, the processing unit feeds back the second ratio to the sender of the digital content, and lowers the priority of the digital content.