JP2017152991A - Information distribution device, information distribution program, communication terminal, communication processing program and information distribution system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information distribution system which is capable of preventing data from being duplicated more than needed and reduces wast of bandwidths of a network.SOLUTION: An information distribution device distribution server 101 comprises: terminal information storage means for storing terminal information of multiple communication terminals that are information distribution destinations; address selection information storage means for storing address selection information for selecting addresses of transmission destinations including an address of a representative communication terminal which is selected from among the multiple communication terminals and relays information distributed from the information distribution device, for each of one or more network segments; transmission address determination means for determining address information to be applied based on the terminal information in the terminal information storage means and the address selection information in the address selection information storage means; and transmission means for transmitting information by using the address information that is determined by the transmission address determination means.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an information distribution apparatus, an information distribution program, a communication terminal, a communication processing program, and an information distribution system. For example, the present invention is applied to an information distribution system that distributes multimedia data including video information and audio information to a plurality of user terminals. It is possible.

  In recent years, due to the development of information communication technology, technology that enables communication between remote places as if they were in the same place and collaborative work has attracted attention. In order to realize this type of technology, an information distribution device (for example, a distribution server) distributes multimedia data including a plurality of video information, audio information, and the like to a plurality of user terminals.

  For example, when distributing multimedia data to a plurality of user terminals, a distribution server having multimedia data obtained from a video source such as a video camera or an audio source such as a microphone requests a user who requests data including video and audio. A method of delivering to a terminal by unicast communication using a UDP packet or the like is used.

  In such unicast communication, when the number of user terminals that request the same data increases, the distribution server replicates and distributes the same data as many as the number of unicast communication channels according to the number of users. There is a problem of wasting.

  As a countermeasure against such a problem, Patent Document 1 discloses a method of avoiding unnecessary duplication of data using a broadcast communication path.

  In Patent Document 1, when the distribution server distributes the same data to a plurality of user terminals, if the number of users requesting the same data is larger than a predetermined threshold, the distribution server uses the broadcast communication path instead of the unicast communication path. A method of using is disclosed.

  As shown in FIG. 2, in the method of Patent Document 1, a distribution server 201 that holds information to be distributed distributes information to a plurality of user terminals 202 that receive the information using a unicast communication path. . For example, when distributing to user terminals 202-2 and 202-5, distribution server 201 distributes information to user terminal 202-2 using unicast communication path UC1, and distribution server 201 uses unicast communication path UC2. Information is distributed to the user terminal 202-5.

  When the number of users who request information distribution is larger than a predetermined threshold (for example, the threshold is 4), the distribution server 201 switches the information to each user terminal 202-1 to 202-5 by switching to the broadcast communication channel BC. To deliver.

Special table 2009-542117 gazette

  However, the technique described in Patent Document 1 discloses only the concept of a distribution method using unicast or broadcast, does not describe a specific distribution method using broadcast, and broadcasts separately from unicast. The disclosure assumes that there is a communication path.

  Further, it is a method that needs to identify whether the broadcast data is data requested by the user by using additional information such as using a separate marker.

  Therefore, when the information distribution device distributes data such as video and audio to multiple user terminals, it avoids duplication of data in the information distribution device, and the user terminal can receive data seamlessly by unicast and broadcast An information distribution apparatus, an information distribution program, a communication terminal, a communication processing program, and an information distribution system are desired.

  The present invention has been made to solve the above-described problems, and employs the following configuration.

  An information distribution apparatus according to a first aspect of the present invention is an information distribution apparatus for distributing information to a plurality of communication terminals. (1) Terminal information storage means for storing terminal information of the plurality of communication terminals that are information distribution destinations And (2) a destination address including an address of a representative communication terminal that relays information distributed from the information distribution device, selected from among the plurality of communication terminals for each of one or a plurality of network segments. Address selection information storage means for storing address selection information for selecting, and (3) application based on the terminal information in the terminal information storage means and the address selection information in the address selection information storage means Transmission address determination means for determining address information; and (4) transmission means for transmitting information using the address information determined by the transmission address determination means. Characterized in that it obtain.

  An information distribution program according to a second aspect of the present invention stores a computer installed in an information distribution apparatus that distributes information to a plurality of communication terminals, (1) stores terminal information of the plurality of communication terminals that are information distribution destinations And (2) an address of a representative communication terminal that relays information distributed from the information distribution device selected from among the plurality of communication terminals for each of one or a plurality of network segments. Address selection information storage means for storing address selection information for selecting a destination address; (3) the terminal information in the terminal information storage means; and the address selection information in the address selection information storage means. Based on transmission address determination means for determining address information to be applied, and (4) information using the address information determined by the transmission address determination means. Characterized in that to function as transmission means for transmitting.

  The communication terminal according to the third aspect of the invention relays information distributed from the information distribution device selected from (1) the information distribution device or a plurality of communication terminals for each one or a plurality of network segments. A receiving unit that receives information distributed from a communication terminal, (2) a retransmission determining unit that determines whether or not the received information received by the receiving unit needs to be relayed, and (3) the retransmission A retransmission unit that retransmits the reception information in the network segment based on a determination result of the transmission determination unit; and (4) a reception data processing unit that performs predetermined information processing on the reception information. Features.

  A communication processing program according to a fourth aspect of the present invention distributes a computer from (1) an information distribution device or the information distribution device selected from a plurality of communication terminals for each one or a plurality of network segments. A receiving unit that receives information distributed from a communication terminal that relays information to be transmitted; (2) a retransmission determining unit that determines whether it is necessary to relay the received information received by the receiving unit; 3) Based on the determination result of the retransmission determination unit, a retransmission unit that retransmits the reception information within the network segment; and (4) a reception data processing unit that performs predetermined information processing on the reception information. It is made to function.

  An information distribution system according to a fifth aspect of the present invention is an information distribution system having one or a plurality of information distribution apparatuses and a plurality of communication terminals. (1) As an information distribution apparatus that is a component of the information distribution system, (2) The communication terminal of the third aspect of the present invention is applied as a communication terminal that is a constituent element of the information distribution system.

  According to the present invention, duplication of data can be avoided more than necessary in the information distribution apparatus, and waste of network bandwidth can be reduced.

  In addition, since a function for performing redistribution is selected from communication terminals that request distribution, it is possible to easily configure an information distribution system without the need for installing a separate redistribution device.

It is a whole lineblock diagram showing the whole information distribution system composition concerning an embodiment. It is explanatory drawing explaining the conventional information delivery process. It is an internal block diagram which shows the internal structure of the delivery server which concerns on embodiment. It is explanatory drawing explaining the structure of the segment list | wrist which concerns on embodiment. It is an internal block diagram which shows the internal structure of the user terminal which concerns on embodiment. It is a flowchart which shows the process in the delivery server of the information delivery system which concerns on embodiment. It is a flowchart which shows the process in the user terminal of the information delivery system which concerns on embodiment.

(A) Main Embodiments Hereinafter, embodiments of an information distribution device, an information distribution program, a communication terminal, a communication processing program, and an information distribution system according to the present invention will be described in detail with reference to the drawings.

(A-1) Configuration of Embodiment FIG. 1 is an overall configuration diagram showing an overall configuration of an information distribution system 10 according to an embodiment.

  In FIG. 1, an information distribution system 10 according to this embodiment includes a distribution server 101 as an information distribution apparatus and a plurality of user terminals 102-1 to 102-5 as communication terminals.

  In the following, when processing and configuration common to user terminals are described, they are expressed as user terminals 102. Although FIG. 1 shows five user terminals 102, the number of user terminals 102 is not limited to this.

  Also, in some segments of the information distribution system 10, user terminals (representative user terminals) that receive packets from the distribution server 101 as a representative and broadcast-distribute to networks within the segment are arranged. In the example of FIG. 1, the user terminal 102-1 is the representative user terminal 102-1. Hereinafter, when the user terminal 102 as the representative user terminal is expressed, it will be described as the representative user terminal 102.

  Further, FIG. 1 shows only one distribution server 101, but a configuration in which a plurality of distribution servers 101 are distributed and a plurality of distribution servers 101 cooperate to distribute requested multimedia data. It may be. For example, the distribution server 101 may be arranged in each of a plurality of bases, and communication may be realized by distributing information bidirectionally between the bases.

  The distribution server 101 uses, for example, content data including video and audio, video data obtained from a video source such as a video camera, and sound data obtained from an audio (sound collecting) source such as a microphone (where “sound” is Multimedia information including a voice, sound, etc.) is distributed to the user terminal 102 that is the distribution request source (or the user terminal 102 that is the distribution request source via the representative user terminal 102). The distribution server 101 may acquire and distribute real-time camera video and microphone sound, or acquire content data and multimedia information from the outside and distribute them to the user terminal 102 or the representative user terminal 102. Alternatively, content data and multimedia data may be held in a database or the like, and the data may be distributed to the user terminal 102 or the representative user terminal 102.

  The user terminal 102 receives information distributed from the distribution server 101 or the representative user terminal 102, and performs video display, sound output, and the like. As the user terminal 102, for example, a personal computer, a tablet terminal, a smartphone, a mobile terminal, or the like equipped with a communication function can be applied. The user terminal 102 receives the information packet address received from the distribution server 101 or the representative user terminal 102 without distinction, and outputs information such as video and sound. That is, the user terminal 102 receives a packet regardless of whether it is a unicast address or a broadcast address, and outputs data (for example, video data, sound data, etc.) included in the received packet. Can do.

  The user terminal 102 (representative user terminal 102) as a representative user terminal has a function of relaying data distributed from the distribution server 101 to the user terminal 102 that is the distribution request source. For example, when the representative user terminal 102 receives distribution data from the distribution server 101, the representative user terminal 102 distributes the received data to other user terminals 102 in the network segment using broadcast.

  FIG. 3 is an internal configuration diagram illustrating an internal configuration of the distribution server 101 according to the embodiment.

  In FIG. 3, the distribution server 101 includes a transmission address determination unit 301, a transmission unit 302, a segment list storage unit 303 as an address selection information storage unit, and a recipient list storage unit 304 as a terminal information storage unit.

  Although the hardware configuration of the distribution server 101 is not shown, it can be a configuration provided in an existing server. For example, a function realized by the distribution server 101 can be realized by including a CPU, an external storage device, a communication device, and the like, and executing the information distribution processing program stored in the storage device. It may be constructed by installing an information distribution processing program. Even in that case, the information distribution processing program can be expressed by the processing illustrated in FIG.

  The recipient list storage unit 304 stores a list including a unicast address of the user terminal 102 that has requested information distribution (hereinafter referred to as “recipient list”). For example, when the distribution server 101 receives an information distribution request from the user terminal 102, the source address included in the packet of the information distribution request is extracted and held in the recipient list storage unit 304. Alternatively, transmission destination address information included in the protocol for signaling the distribution request is held in the recipient list storage unit 304. The recipient list may hold redistribution reception port information used when the user terminal 102 is selected as the representative user terminal.

  In this embodiment, for ease of explanation, the unicast address of the user terminal 102 of the transmission destination (that is, the information distribution request source) of transmission data such as certain content data and multimedia data is listed. It is assumed that there is. Of course, when there are a plurality of types of transmission data such as a plurality of content data and multimedia data, for example, for each transmission data identification information (for example, content identification information), the unicast of the user terminal 102 of the information distribution request source A list of addresses may be set.

  The segment list storage unit 303 stores the network address and netmask of the target network segment for each network segment in which the user terminal 102 can exist, the address of the representative user terminal 102 selected for each target network segment, and the representative user from the unicast distribution. A segment list that associates a threshold value for switching to broadcast distribution via the terminal 102 is stored.

  FIG. 4 is an explanatory diagram illustrating the configuration of the segment list according to the embodiment. 4 illustrates the case where the IP address is IPv4, but the case where the IP address is IPv6 can be set based on the same concept as in the case of IPv4.

  As shown in FIG. 4, the segment list includes “Segment No.”, “Network Address / Netmask”, “Representative User Terminal Address”, and “Threshold” that identify network segments.

  For example, the network address and netmask of “Segment No. 1” are “xx.xx.xx.0 / 24”. Since the netmask is 24, the upper 24 bits of the 32-bit IP address are the network address (network part) indicating the network segment, and the remaining 8 bits (from the 25th bit to the 32nd bit) Is a host address (host part) for identifying the user terminals 102 belonging to the network segment.

  The “representative user terminal address” is a unicast address of a representative user terminal selected from among the plurality of user terminals 102 for the network segment. For example, the representative user terminal address of “Segment No. 1” is “xx.xx.xx.1” (corresponding to the address of the user terminal 102-1 in FIG. 1).

  Note that the “representative user terminal address” is not necessarily set for the network segment. For example, if the distribution server 101 has not yet selected a representative user terminal from among the user terminals 102 belonging to a certain network segment (for example, the network status of the network segment 2 in FIG. 1), this field may be blank. Further, when the “representative user terminal address” is blank, the distribution server 101 performs processing such as unicast distribution to each user terminal 102 regardless of the number of user terminals 102 that have requested information distribution. You can go.

  The “threshold value” is a threshold value for switching from unicast to the user terminal 102 to broadcast distribution via the representative user terminal 102. This threshold value is compared with the number of user terminals 102 that have requested information distribution in the network segment. The threshold value may be arbitrarily set, may be different for each network segment, or may be the same value for all network segments. In the network segment, when the number of user terminals 102 that have requested information distribution is equal to or greater than a threshold, the corresponding “representative user terminal address” is used. For example, the distribution server 101 distributes data to the user terminal 102 via the representative user terminal 102 when the number of user terminals 102 that requested information distribution is three or more.

  When the transmission address determination unit 301 acquires transmission data such as content data and multimedia data to be transmitted to the user terminal 102, the transmission address determination unit 301 transmits the unicast of the user terminal 102 that is the distribution request source of the transmission data from the recipient list storage unit 304. Read the address. The transmission address determination unit 301 obtains the number of user terminals 102 for each network segment (more precisely, the number of addresses for each network segment) based on the unicast address read from the recipient list storage unit 304.

  The transmission address determination unit 301 refers to the segment list storage unit 303 and compares the number of user terminals 102 for each network segment with the threshold value of the corresponding network segment.

  When the number of user terminals 102 requesting information distribution is equal to or greater than the threshold, the transmission address determination unit 301 distributes to the user terminals 102 existing in the network segment using the address of the representative user terminal 102. decide. In other words, when there are more user terminals 102 set in the segment list than the corresponding network segment threshold, one address addressed to the representative user terminal 102 should be used for these user terminals 102. Thus, it is possible to reduce the processing load and the number of copies related to the transmission data replication of the distribution server 101.

  On the other hand, when the number of user terminals 102 requesting information distribution is less than the threshold, the transmission address determination unit 301 determines to distribute to each user terminal 102 using a unicast address.

  When there are a plurality of types of transmission data, the transmission address determination unit 301 refers to the identification information of the transmission data, refers to the recipient list set for each identification information of the transmission data, and transmits the transmission data. The number of data transmission destinations (number of distribution destinations) may be confirmed.

  The transmission unit 302 transmits the transmission data using the address determined by the transmission address determination unit 301. The transmission unit 302 uses the result determined by the transmission address determination unit 301 to copy a necessary number of transmission data according to the number of distribution destinations.

  FIG. 5 is an internal configuration diagram illustrating an internal configuration of the user terminal 102 (representative user terminal 102) according to the embodiment.

  In FIG. 5, the user terminal 102 includes a reception unit 401, a reception data processing unit 402, a retransmission determination unit 403, and a retransmission unit 404.

  Note that the hardware configuration of the user terminal 102 is not shown, but may be a configuration provided in an existing communication terminal. For example, a function realized by the user terminal 102 can be realized by including a CPU, a storage device, a communication device, and the like, and executing a communication processing program stored in the storage device. It may be constructed by installing a communication processing program. Even in that case, the communication processing program can be expressed by the processing illustrated in FIG.

  The receiving unit 401 is a communication interface that receives data (packets) from the distribution server 101 or another user terminal 102.

  The reception data processing unit 402 is a functional unit that performs normal processing as a user terminal on received data. For example, when the received data is video data, the received data processing unit 402 performs processing using the data received as a user terminal, such as video display processing.

  The retransmission determination unit 403 determines (determines) whether it is necessary to retransmit the received data. For example, the retransmission determination unit 403 may use a port number of received data, although the determination method is not limited.

  For example, the reception port number of the data received by the receiving unit 401 (distribution data of the distribution server 101) includes a case where the user terminal 102 to be distributed functions as a representative user terminal and a case where the user terminal 102 functions as a user terminal. Assume that different port numbers are specified for distinction. Then, retransmission determination section 403 refers to the reception port number of the received data and determines whether the data needs to be retransmitted.

  The retransmission determination unit 403 retransmits the received data as a broadcast within the network segment when the retransmission determination unit 403 determines (decides) to retransmit (in other words, functions as a representative user terminal). (Relay distribution).

(A-2) Operation | movement of embodiment Next, operation | movement of the process in the information delivery system 10 which concerns on this embodiment is demonstrated with reference to drawings.

  FIG. 6 is a flowchart showing processing in the distribution server 101 of the information distribution system 10 according to the embodiment.

  In FIG. 1, user terminals 102-1 to 102-5 make a distribution request for information to the distribution server 101.

  Note that the user terminals 102-1 to 102-3 belong to the network segment 1 (network address; “xx.xx.xx.0”), and the IPv4 IP of the user terminals 102-1 to 102-3. The addresses are “xx.xx.xx.1”, “xx.xx.xx.2”, and “xx.xx.xx.3”, respectively, and the netmask is a 24-bit prefix. It is assumed that the user terminal 102-1 is selected as the representative user terminal 102-1 for the network segment 1.

  Similarly, the user terminals 102-4 to 102-5 belong to the network segment 2 (network address; “yy.yy.yy.0”), and the IPv4 of the user terminals 102-4 to 102-5 The IP addresses are “yy.yy.yy.4” and “yy.yy.yy.5”, respectively, and the netmask is a 24-bit prefix. It is assumed that no representative user terminal has been selected for the network segment 2 yet.

  Although the description here uses an example of using the IPv4 protocol and UDP packet, the same processing is possible when using other network layer protocols such as IPv6 or using transport layer protocols other than UDP packets. It is.

  Upon receiving a distribution request from the user terminals 102-1 to 102-5, the distribution server 101 distributes the requested transmission data using unicast or broadcast via the representative user terminal 102-1.

  Here, the recipient list stored in the recipient list storage unit 304 of the delivery server 101 includes “xx.xx.xx.1”, “xx.xx.xx.” for the transmission data to be delivered this time. 2 ”,“ xx.xx.xx.3 ”,“ yy.yy.yy.4 ”, and“ yy.yy.yy.5 ”are set.

  Assume that the list illustrated in FIG. 4 is set in the segment list stored in the segment list storage unit 303 of the distribution server 101.

  Further, in this embodiment, the transmission address determination unit 301 determines whether the distribution data transmission destination user terminal 102 functions as a representative user terminal and a case where the distribution data transmission destination user terminal 102 functions as a user terminal. It is determined that a different port number (either a unicast reception port number or a retransmission trusted reception port number) is designated as the port number for transmission.

  In the receiver list, it is assumed that either the unicast reception port number or the retransmission trusted reception port number is associated with the address of each user terminal 102 in advance.

  In the following, for simplification of description, “pp” is used as the unicast reception port number, and “qq” is used as the retransmission trusted reception port number, assuming that the entire information distribution system 10 is used.

  In the distribution server 101, the transmission data requested for distribution is given to the transmission address determination unit 301 (S101).

  The transmission address determination unit 301 reads the unicast address of the user terminal 102 that is the transmission request destination of the transmission data from the recipient list storage unit 304, and confirms the number of user terminals 102 for each network segment (S102).

  For example, the recipient list stored in the recipient list storage unit 304 includes “xx.xx.xx.1: pp”, “xx.xx.xx.2: pp” for transmission data to be distributed this time. "Xx.xx.xx.3: pp", "yy.yy.yy.4: pp", and "yy.yy.yy.5: pp" are set. Therefore, there are three addresses belonging to the network segment 1, namely “xx.xx.xx.1: pp”, “xx.xx.xx.2: pp”, and “xx.xx.xx.3: pp”. The transmission address determination unit 301 confirms that there are two addresses belonging to the network segment 2: “yy.yy.yy.4: pp” and “yy.yy.yy.5: pp”.

  Next, the transmission address determination unit 301 refers to the segment list storage unit 303 and compares the number of user terminals for each network segment with the threshold value of the corresponding network segment (S103).

  When the number of user terminals for each network segment is equal to or greater than the threshold (S104), the user terminals 102 belonging to the network segment are given a unicast address and retransmission trusted reception port number (qq) of the representative user terminal 102, ie, “xx. .Xx.1: qq "is used (S105).

  On the other hand, when the number of user terminals for each network segment is less than the threshold (S104), a unicast address and a unicast reception port number (pp) are used for each user terminal 102 (S106).

  For example, as described above, the address of the transmission destination of the transmission data read from the recipient list is “xx.xx.xx.1”, “xx.xx.xx.2”. ”And“ xx.xx.xx.3 ”. It is “threshold value: 3” set in the network segment 1 of the segment list illustrated in FIG. Therefore, the number of user terminals in the network segment 1 is greater than or equal to the threshold value. Therefore, the transmission address determination unit 301 reads the corresponding unicast address and port number “xx.xx.xx.1: qq” of the representative user terminal 102-1 from the segment list in FIG. For the user terminals 102-2 and 102-3, it is determined to perform distribution via the representative user terminal 102-1.

  Further, for example, there are two addresses belonging to the network segment 2, “yy.yy.yy.4” and “yy.yy.yy.5”. It is “threshold value: 3” set in the network segment 2 in the segment list illustrated in FIG. Therefore, the number of user terminals in the network segment 2 is less than the threshold value. Therefore, the transmission address determination unit 301 sends unicast addresses and port numbers “yy.yy.yy.4: pp” and “yy.yy” to the user terminals 102-4 to 102-5 belonging to the network segment 2. .Yy.5: pp ".

  The transmission unit 302 duplicates the transmission data according to the number of addresses to be transmitted generated by the transmission address determination unit 301 (S107). Then, the unicast address and port number determined by the transmission address determination unit 301 are added to the transmission data and transmitted (S108).

  For example, in S104 to S106, the transmission address determination unit 301 determines that “xx.xx.xx.1: qq” of the user terminal 102-1 and “yy.yy.yy.4: pp” of the user terminal 102-4, Three unicast addresses and port numbers of “yy.yy.yy.5: pp” of the user terminal 102-5 were determined. Therefore, the transmission unit 302 duplicates the transmission data so as to be three pieces of transmission data, and transmits the transmission data with an address and a port number to be transmitted.

  FIG. 7 is a flowchart illustrating processing in the user terminal 102 of the information distribution system 10 according to the embodiment.

  In the user terminal 102, the data received by the receiving unit 401 is given to the retransmission determining unit 403 (S201).

  The retransmission determination unit 403 determines whether the received data is data that needs to be retransmitted based on the port number of the data received by the reception unit 401 (S202, S203).

  Specifically, retransmission determination section 403 determines that there is no need for retransmission when the reception port number of the received data is a unicast reception port number (pp), and will be described later in step S205. Perform the process. On the other hand, when the reception port number of the received data is the retransmission trusted reception port number (qq), the retransmission determination unit 403 determines that retransmission is necessary, and performs the process of the next step S204. Do.

  When the retransmission determining unit 403 determines that retransmission is necessary, the retransmission unit 404 redistributes the received data to the broadcast address in the network segment as a representative user terminal (S204). For example, the user terminal 102-1 which is the representative user terminal transmits the data received to “xx.xx.xx.1: qq” to the broadcast address “xx.xx.xx.255: pp”. .

  The received data processing unit 402 performs normal processing (video playback processing, audio playback processing, etc.) using received data as a user terminal (S205). For example, the user terminals 102-4 and 102-5 perform normal processing on the data received addressed to “yy.yy.yy.4: pp” and “yy.yy.yy.5: pp”. In addition, as the representative user terminal, the user terminal 102-1 that has performed the retransmission process in step S204 described above also performs the process in step S205 as a user terminal.

  In steps S202 and S203 described above, the retransmission determination unit 403 uses the reception port number to determine whether or not retransmission is necessary. However, the present invention is not limited to this. For example, when the transmission server 101 switches the transmission source port number and transmits data, the retransmission determination unit 403 refers to the transmission source port number and determines whether or not retransmission is necessary based on this. It is good also as such a structure.

  Through the processing as described above, the information distribution system 10 selectively distributes information using a broadcast via the representative user terminal 102 instead of transmitting all of the recipients in the recipient list by unicast. .

(A-3) Effects of Embodiment As described above, according to this embodiment, the following effects can be obtained.

  In the distribution server, for a network segment that has a transmission request from a user terminal exceeding the threshold, a packet is transmitted to the address of the representative user terminal instead of copying and transmitting the packet to each unicast address. Therefore, duplication of data more than necessary can be avoided, and waste of network bandwidth can be reduced.

  In addition, since a function for performing redistribution is selected from user terminals requesting distribution, it is possible to easily configure a distribution system without the need for installing a separate redistribution device.

(B) Other Embodiments Although various modified embodiments are mentioned in the above-described embodiments, the present invention can also be applied to the following modified embodiments.

  (B-1) In the embodiment described above, the network segment 1 in which the user terminal 102 assumed as a delivery destination may exist has the address of the user terminal 102-1 as a representative user terminal described in the segment list. An example is shown (see FIGS. 1 and 4).

  However, for example, there may be a case where the address of the representative user terminal is undecided due to dynamic addition or deletion of the recipient list. In such a case, the distribution server 101 refers to the recipient list in the recipient list storage unit 304, selects one address from the user terminals 102 that can be retransmitted, and sets it as the representative user terminal address. (Set to “Representative user terminal address” in the segment list). For example, when a new user terminal 102-6 (“yy.yy.yy.6”) participates in the network segment 2, the distribution server 101 connects the network from the user terminals 102-4 to 102-6. A representative user terminal for segment 2 is selected.

  When the user terminal-102-6 is a terminal that can be retransmitted, for example, when the distribution request is started, the user terminal-102-6 may notify the distribution server 101 of its own network address / netmask. Further, the distribution server 101 has a relay address information receiving unit that receives the network address / netmask. The distribution server 101 stores the notified network address / netmask in the recipient list, and reconfigures the segment list based on the network address / netmask (the value of each item in the segment list is changed). Delete or add).

  (B-2) In the above-described embodiment, when network segments in which user terminals assumed as distribution destinations can exist are specified in advance, a list for each network segment is listed as in the segment list of FIG. The case was illustrated.

  However, for example, when it is not possible to enumerate network segments in the segment list, it may be requested from a user terminal belonging to a network segment not set in the segment list. In this case, for example, in addition to the segment list of FIG. 4, a predetermined threshold value and a predetermined net mask may be set. That is, a default threshold value and a net mask may be set. For example, for a unicast address belonging to a network segment not listed in the segment list, an entry exists in the segment list in which a network address derived by a default netmask and a corresponding default threshold are set. Address determination processing may be performed.

  For example, it is assumed that a default threshold 3 and a 24-bit prefix as a default netmask are set as defaults. Assume that there is a unicast address “zz.zz.zz.7” in which no entry exists in the segment list of FIG. The distribution server 101 has a network address “zz.zz.zz.0 / 24” derived from 101, a unicast address “zz.zz.zz.7” and a default netmask “24”, a default Address determination processing is performed assuming that there is an entry in the segment list for which threshold 3 is set. The distribution server 101 may be configured to add an entry to the segment list upon receiving a notification of a retransmittable network address / netmask when a transmission start request is received from the user terminal 102.

  (B-3) In the above-described embodiment, among the user terminals 102, the user terminals 102-2 to 102-3 are not addressed to unicast addresses, but packets addressed to broadcast addresses via the representative user terminal 102-1. Will receive. However, the user terminal 102 waits for a packet without specifying the reception address, and ignores the reception address of the actually received packet to process it, when receiving at the unicast address and when receiving at the broadcast address It is possible to receive data seamlessly without distinguishing between them.

  (B-4) When simultaneously distributing a plurality of data having different contents such as video and audio (that is, when receiving different media data for each application), for example, when using UDP, the items of the segment list and the recipient list For example, the type of data to be received may be specified by setting a UDP port number. Further, not only the reception port number but also the IP address and port number of the transmission source may be used for determining the data type.

  For example, the segment list entry in FIG. 4 is configured to hold the segment list using the transport layer port number information as a key in addition to the network address. The recipient list lists pairs of recipient (user terminal) unicast addresses and reception port numbers. That is, even if the user terminal has the same broadcast address, if the port number is different, it is transmitted as another packet.

  (B-5) The present invention is not limited to the above-described embodiment, and can be used for various other information distribution apparatuses.

  For example, as in a multipoint conference system, it can be used for various data distribution such as distribution of information such as documents and presentations in addition to video and audio data.

  For example, the present invention is not limited to a specific protocol such as IPv4 or UDP, and can be applied to various information distribution systems such as using other network protocols such as IPv6 and transport protocols.

  DESCRIPTION OF SYMBOLS 10 ... Information delivery system, 101 ... Delivery server, 102 ... User terminal, 301 ... Transmission address determination part, 302 ... Transmission part, 303 ... Segment list storage part, 304 ... Recipient list storage part, 401 ... Receiving part, 402 ... Received data processing unit, 403... Retransmission determination unit, 404.

Claims (16)

In an information distribution apparatus that distributes information to a plurality of communication terminals,
Terminal information storage means for storing terminal information of the plurality of communication terminals which are information distribution destinations;
For selecting an address of a transmission destination including an address of a representative communication terminal that relays information distributed from the information distribution device, selected from among the plurality of communication terminals, for each of one or a plurality of network segments Address selection information storage means for storing address selection information;
A transmission address determining means for determining address information to be applied based on the terminal information in the terminal information storage means and the address selection information in the address selection information storage means;
An information distribution apparatus comprising: transmission means for transmitting information using the address information determined by the transmission address determination means.   2. The information according to claim 1, wherein the transmission address determination means determines address information according to the number of transmission destinations for each network segment derived based on the terminal information and the address selection information. Distribution device. The terminal information storage means stores the unicast addresses of the plurality of communication terminals as the terminal information;
The address selection information storage means stores information including the unicast address of the representative communication terminal as the address selection information.
The transmission address determination means determines a unicast address of either the plurality of communication terminals or the representative communication terminal according to the number of transmission destinations for each network segment. The information distribution apparatus described.   When the address of the representative communication terminal is not stored for one or a plurality of network segments, the address selection information storage means refers to the terminal information, and from among the communication terminals belonging to the target network segment. 4. The information distribution apparatus according to claim 1, wherein the representative communication terminal is selected, and an address of the selected representative communication terminal is stored. Relay address information receiving means for receiving notification of relay address information including a network address that can be retransmitted by the communication terminal that is the distribution request source, for information distributed from the information distribution device,
The terminal information storage means stores the relay address information in the terminal information when the relay address information is received by the relay address information receiving means;
The information distribution apparatus according to claim 1, wherein the address selection information storage unit reconfigures the address selection information based on the received relay address information. The address selection information storage means stores information including a port number as the address selection information.
The terminal information storage means stores information including a reception port number as the terminal information;
The information transmission apparatus according to claim 1, wherein the transmission unit transmits information using the address information and the port number determined by the transmission address determination unit.   The information distribution apparatus according to claim 1, wherein the information includes video information.   The information distribution apparatus according to claim 1, wherein the information is information including sound information. A computer installed in an information distribution device that distributes information to a plurality of communication terminals,
Terminal information storage means for storing terminal information of the plurality of communication terminals which are information distribution destinations;
For selecting an address of a transmission destination including an address of a representative communication terminal that relays information distributed from the information distribution device, selected from among the plurality of communication terminals, for each of one or a plurality of network segments Address selection information storage means for storing address selection information;
A transmission address determining means for determining address information to be applied based on the terminal information in the terminal information storage means and the address selection information in the address selection information storage means;
An information distribution program that functions as a transmission unit that transmits information using the address information determined by the transmission address determination unit. A receiving unit that receives information distributed from a communication terminal that relays information distributed from the information distribution apparatus or the information distribution apparatus selected from a plurality of communication terminals for each one or a plurality of network segments When,
A retransmission determination unit that determines whether it is necessary to relay the reception information received by the reception unit;
Based on the determination result of the retransmission determination unit, a retransmission unit that retransmits the reception information in a network segment;
A communication terminal comprising: a reception data processing unit that performs predetermined information processing on the reception information.   The communication terminal according to claim 10, wherein the reception unit receives information regardless of an address type of the reception information.   12. The retransmission determination unit according to claim 10 or 11, wherein the retransmission determination unit determines whether or not the reception information needs to be relayed in consideration of a reception port number given to the reception information. Communication terminal.   The retransmission determination unit determines whether or not it is necessary to relay the reception information in consideration of a transmission source port number given to the reception information. The communication terminal according to any one of the above.   The communication terminal according to claim 10, wherein the retransmission unit broadcast-distributes the reception information in a network segment based on a determination result of the retransmission determination unit. Computer
A receiving unit that receives information distributed from a communication terminal that relays information distributed from the information distribution apparatus or the information distribution apparatus selected from a plurality of communication terminals for each one or a plurality of network segments When,
A retransmission determination unit that determines whether it is necessary to relay the reception information received by the reception unit;
Based on the determination result of the retransmission determination unit, a retransmission unit that retransmits the reception information in a network segment;
A communication processing program that causes the reception information to function as a reception data processing unit that performs predetermined information processing. In an information distribution system having one or a plurality of information distribution apparatuses and a plurality of communication terminals,
Applying the information distribution device according to any one of claims 1 to 8 as an information distribution device as a component of the information distribution system,
The communication terminal according to any one of claims 10 to 14 is applied as a communication terminal which is a constituent element of the information distribution system.

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