KR100841593B1 - Appratus and method for providing multimedia contents, and appratus and method for receiving multimedia contents - Google Patents

Abstract

An apparatus and a method for providing multimedia contents, and an apparatus and a method for receiving multimedia contents are provided to reduce bandwidth requests of a network and to increase the number of receiving stages of a server performing a service, thereby maximizing usage efficiency of the network. A connection confirmation unit(210) confirms whether a second multimedia data receiver receiving the same contents as contents requested from a first multimedia data receiver, through a first multicast session exists. If so, a session management unit(220) transmits a part of the requested contents by setting up a second multicast session while maintaining provision of contents through the first multimedia session.

Description

Apparatus and method for providing multimedia contents, and appratus and method for receiving multimedia contents

1 is a view showing the configuration of an entire network consisting of a multimedia content providing apparatus and a receiving apparatus according to the present invention;

2 is a block diagram showing a detailed configuration of a preferred embodiment of a multimedia content providing apparatus according to the present invention;

3 is a flowchart illustrating a process of providing multimedia content by the apparatus shown in FIG. 2;

4 is a block diagram showing a detailed configuration of a preferred embodiment of a multimedia content receiving apparatus according to the present invention;

5 is a flowchart illustrating a process of receiving multimedia content by the apparatus shown in FIG. 4;

FIG. 6 is a diagram illustrating a situation in which n to n + 6 portions of the same content are already transmitted through another multicast session when a new multimedia content receiving device requests to provide content.

7 is a diagram illustrating a content providing process according to time slots of a multimedia content providing apparatus when a request for providing identical contents is received from two multimedia content receiving apparatuses;

FIG. 8 is a diagram illustrating a content providing process for each time zone of a multimedia content providing apparatus when there is a request for providing the same content from three multimedia content receiving apparatuses.

FIG. 9 is a diagram illustrating a content providing process for each time zone of a multimedia content providing apparatus when a request for providing identical contents is received from four multimedia content receiving apparatuses.

The present invention relates to an apparatus and method for providing multimedia content, and to an apparatus and method for receiving multimedia content. More particularly, the present invention relates to a method for transmitting multimedia content such as a video and audio in an IP environment. An apparatus and method for transmitting and receiving to multiple viewers using casts.

In general, there are unicast, multicast, and broadcast transmission methods for transmitting packet data in the Internet environment.

Unicast transmission method is a one-to-one transmission between a single sender and a single receiver in packet data transmission, and has the advantage of being able to transmit data packets independently and to transmit desired packet data. However, when one sender transmits a data packet independently to a plurality of receivers, each packet data must be separately transmitted to each receiver. Therefore, there is a problem that the transmission efficiency is generally reduced due to excessive burden on the sender server capacity and excessive network bandwidth requirements.

In the broadcast transmission method, one sender simultaneously transmits data to all receivers on the same subnetwork. This has the advantage that the same packet data can be delivered to multiple senders. However, there is a problem in that even if the receiver does not want to receive the transmitted packet.

Unlike the broadcast method, the multicast transmission method sets and transmits a specific Internet address area only to users of a single group or a group of users who want to receive the broadcast. That is, if one of the receivers of the multicast target group address receives the packet data through IPv4 and IPv6 address setting for multicast transmission, the receiver in the area simultaneously receives the same packet data replicated through the subnetwork gateway. The difference is that you can receive. Therefore, unlike unicast, the network or server is not overloaded.

In IPTV or Internet TV services currently serving internationally, VoD content is mainly transmitted using unicasting. As described above, the unicasting method secures an individual band for each receiver by transmitting a content by the receiving end of the content request. Therefore, the network bandwidth demand increases in proportion to the increase of the request for content transmission from the receiving end, and if the number of recipients explodes for the popular content, the network and the server may become excessive and the transmission quality may be significantly reduced or stopped.

On the other hand, a method of transmitting VoD content by multicast at regular time intervals has also been proposed, but in this case, the start time of the video is determined according to a predetermined interval, and in order for a user to watch the content at the same time as the request for providing the content, The location where is started and the user's request time must match. Therefore, it is difficult to provide VoD content in real time in response to a user's request immediately.

The technical problem to be achieved by the present invention is to provide a multimedia content providing apparatus that can significantly reduce the bandwidth requirements of the network and significantly increase the number of receiving end of the server at the same time when providing VoD service in the IP environment and the prior art; To provide a way.

Another technical problem to be solved by the present invention is to provide a VoD service in an IP environment, which can significantly reduce the bandwidth requirement of a network and increase the number of receiving terminals of a server that can simultaneously service a conventional multimedia content. And a method.

Another technical problem to be solved by the present invention is to provide a multimedia content that can greatly reduce the bandwidth requirement of the network and to substantially increase the number of receiving terminals that can serve simultaneously when providing VoD service in an IP environment. The present invention provides a computer-readable recording medium that records a program for executing a public method and a receiving method on a computer.

According to an aspect of the present invention, there is provided a multimedia content providing apparatus according to the present invention, wherein the same content as the content requested from the first multimedia data receiving apparatus connected through a network is provided through a first multicast session. A connection confirmation unit confirming whether a multimedia data receiving apparatus exists; And a session manager configured to set a second multicast session and transmit a portion of the requested content while maintaining the provision of the content through the first multicast session, if the second multimedia data receiver exists.

In accordance with another aspect of the present invention, there is provided a method for providing multimedia content according to the present invention, wherein the same content as that requested from the first multimedia data receiving apparatus connected through a network is provided through a first multicast session. Checking whether a multimedia data receiving apparatus exists; And if the second multimedia data receiving apparatus is present, establishing a second multicast session while maintaining the provision of the content through the first multicast session, and transmitting a portion of the requested content. In the multicast session, if a content portion corresponding to the time from providing the content to the second multimedia data receiving apparatus to the time of providing the content to the first multimedia data receiving apparatus is transmitted to the first multimedia data receiving apparatus. Is released.

In accordance with another aspect of the present invention, there is provided a multimedia content receiving apparatus, comprising: a content requesting unit requesting to provide content requested from a user to a content providing apparatus connected through a network; A content receiving unit which receives a content transmitted from the content providing device through a multicast session; A content storage unit for storing content received through a first multicast session set up before requesting to provide the content to the content providing device; And outputting the content received from the content providing device through a second multicast session, and when the second multicast session is released, continuously receiving the content received through the first multicast session stored in the content storage unit. It has a content output unit for outputting.

In accordance with another aspect of the present invention, there is provided a method for receiving multimedia content, the method comprising: requesting a content providing apparatus connected through a network to provide content requested from a user; Receiving the content requested from the user through a first multicast session established before requesting the content providing apparatus to provide the content and storing the received content in the storage means; And outputting the content received from the content providing device through a second multicast session, and continuously outputting the content received through the first multicast session stored in the storage means when the second multicast session is released. Comprising;

As a result, the bandwidth requirements of the network can be greatly reduced, and the number of receiving terminals of servers that can be serviced can be greatly increased, thereby maximizing network usage efficiency.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the multimedia content providing apparatus and method, and the multimedia content receiving apparatus and method according to the present invention.

1 is a diagram illustrating a configuration of an entire network including a multimedia content providing apparatus and a receiving apparatus according to the present invention.

Referring to FIG. 1, the entire network includes a multimedia content providing apparatus 110 and a plurality of multimedia content receiving apparatuses 120, 130, 140, and 150. The multimedia content providing apparatus 110 may be a media server or a streaming server that provides multimedia content as a multicasting method for providing content requested from the multimedia content receiving apparatuses 120, 130, 140, and 150. The multimedia content receivers 120, 130, 140, and 150 are devices that receive and provide content from a network between an Ethernet switching device such as a set-top box and an output device for outputting multimedia content to a subscriber. In this case, the multimedia content receiving apparatuses 120, 130, 140, and 150 are devices belonging to a network having a multicast address belonging to class D.

2 is a block diagram showing a detailed configuration of a preferred embodiment of the apparatus for providing multimedia contents according to the present invention, and FIG. 3 is a flowchart illustrating a process of providing multimedia contents by the apparatus shown in FIG.

2 and 3, the multimedia content providing apparatus 110 according to the present invention includes a connection confirming unit 210 and a session managing unit 220.

The access checker 210 determines whether to accept the content providing request of the first multimedia data receiving device 120 connected through the network (S300). When it is determined to provide the content to the first multimedia data receiving apparatus 120, the connection checker 210 first broadcasts the same content as the content requested from the first multimedia data receiving apparatus 120 connected through the network. In operation S310, it is determined whether or not the second multimedia data receiving apparatus 130 provided through the session exists. The multimedia content providing apparatus 110 and each of the multimedia data receiving apparatuses 120, 130, 140, and 150 perform communication using the IGMP protocol, and the multimedia data receiving apparatus 120, in the Internet Group Management Protocol (IGMP) protocol, In 130, 140, and 150, a message for joining or leaving a multicast group is transmitted to the multimedia content providing apparatus 110. In this case, the multimedia content providing apparatus 110 may determine whether to request the same content by checking the multicast group in which the multimedia data receiving apparatuses 120, 130, 140, and 150 request to participate.

If there is no second multimedia data receiving device 130 that is provided with the same content as the content requested by the first multimedia data receiving device 120 before the request of the first multimedia data receiving device 120, the session manager 220. Establishes a new multicast session to provide the requested content (S320). On the contrary, if there is a second multimedia data receiving apparatus 130 that receives the same content as the content requested by the first multimedia data receiving apparatus 120 before the request of the first multimedia data receiving apparatus 120, the session manager 220 ) Establishes the second multicast session while maintaining the provision of the content through the first multicast session, and transmits a part of the content requested by the first multimedia data receiving apparatus 120 (S330). At this time, the session managing unit 220 corresponds to the first multimedia data in which the content portion corresponding to the point of time when the content is provided to the second multimedia data receiving apparatus 130 starts to provide the content to the first multimedia data receiving apparatus 120. When transmitted to the receiving device 120 releases the second multicast session (S340).

4 is a block diagram showing a detailed configuration of a preferred embodiment of a multimedia content receiving apparatus according to the present invention, and FIG. 5 is a flowchart illustrating a process of receiving multimedia content by the apparatus shown in FIG.

4 and 5, the multimedia content receiving apparatus 120 according to the present invention includes a content requesting unit 410, a content receiving unit 420, a content storage unit 430, and a content output unit 440. .

The content requesting unit 410 requests the provision of the content requested from the user to the multimedia content providing apparatus 110 connected through the network (S500). The content receiver 420 receives content transmitted from the multimedia content providing apparatus 110 through a multicast session. In this case, the receiving operation by the content receiving unit 420 depends on whether the multimedia content providing apparatus 110 is transmitting the same content as the content requested from the user. If there is no request for provision of the same content by another multimedia content receiving apparatus (for example, the content receiving apparatus with reference numeral 130 in FIG. 1) (S510), the content receiving unit 420 may determine that the multimedia content providing apparatus 110 is selected. The content provided by the multicast method is received (S520), and the content output unit 440 outputs the received content (S530).

In contrast, another multimedia content receiving apparatus 130 requests the provision of the same content before the content providing request is received by the content requesting unit 410, and in response, the multimedia content providing apparatus 110 establishes a first multicast session. If the content is being transmitted through (S510), the content receiving unit 420 receives the content through the first multicast session and simultaneously receives the content received from the multimedia content providing apparatus 110 through the second multi-catalytic session. Receive (S540). The content received through the first multicast session is stored in the content storage unit 430 (S550). After outputting the content received through the second multicast session, the content output unit 440 releases the second multicast session or stores the beginning of the content stored in the content storage unit 430 and the second multicast session. At the same time, the content received through the read-out content stored in the content storage unit 430 and outputs (S560). In this case, the second multicast session is released when the content portion corresponding to the content is transmitted from the time point at which the content is provided to the other multimedia content receiving device 130 to the time point at which the content starts to be provided through the second multicast session.

On the other hand, the multimedia content receiving apparatus uses the Extended Highest Sequence Number Field, Packet Count Field, and Profile-specific Extensions Field of the Real-time Trasport Control Protocol (RTCP) message field and the beginning of the stored content and the second multicast session. Received through and check whether the part being output is the same. RTCP is a protocol for providing control packets of the Real-time Transport Protocol (RTP), and RTP is a protocol that provides the function of transmitting audio, video and data in real time. At this time, the message is periodically transmitted through RTCP to provide information related to the transmitted data packet and data quality.

FIG. 6 is a diagram illustrating a situation in which n to n + 6 portions of the same content are already transmitted through another multicast session when the new multimedia content receiving device requests to provide the content. In Figure 6, n and i are Random Initial Sequence Number.

Referring to FIG. 6, a new multimedia content receiving apparatus receives an n + 7 th multicast packet and stores it in a storage means. When the first Random Sequence Number Packet i arrives through the newly established multicast session, the multimedia content receiver uses the RTCP Profile-specific Extensions Field to send the seven multimedia content packets from i to i + 6th to the multimedia content provider. Only ask to send. The multimedia content receiving apparatus requests release of a new multicast session when all seven packets arrive.

FIG. 7 is a diagram illustrating a content providing process for each time zone of a multimedia content providing apparatus when a request for providing identical contents is received from two multimedia content receiving apparatuses.

7, the first multimedia content receiving unit 120, the time requested content (t ₁₎ than the first, the same sub-second multimedia contents received in the network device 130 is t ₀ is already the same content, the first from the time Received by multicast (M ₁ ). Therefore, the first multimedia content receiving apparatus 120 may provide only the contents (c ₁ , c ₂ , c ₃ ) already received by the second multimedia content receiving apparatus 130 for t ₁ -t ₀ time. Request to the _second multicast (M ₂ ), and at the same time the content (from c ₄ ) received through the _first multicast (M ₁ ) from time t ₁ together with the second multimedia content receiving apparatus (130) Receive and store in the storage means. The first multimedia content receiving apparatus 120 outputs the contents (c ₁ , c ₂ , c ₃ ) received through the _second multicast (M ₂ ) immediately on the screen. When the first multimedia content receiving device 120 receives and outputs all of the portions c ₁ , c ₂ , and c ₃ already received by the first multimedia receiving device 130 through the _second multicast M ₂ . (that is, if t ₁ -t ₀ time from the time point t _1), reads the content (c from ₄₎ stored in the storage means and outputs it to the screen.

FIG. 8 is a diagram illustrating a content providing process for each time zone of a multimedia content providing apparatus when a request for providing identical contents is received from three multimedia content receiving apparatuses. In FIG. 8, the content providing process associated with the two multimedia content receiving apparatuses 120 and 130 that have requested the content is the same as described with reference to FIG. 7. Therefore, only the content providing process related to the third multimedia content receiving device 140 which requests the provision of the same content is described.

Referring to FIG. 8, the third multimedia content receiving apparatus 140 transmits the content (c ₅ ) transmitted by the multimedia content providing apparatus 110 to the first multicast M ₁ at the time t ₂ of requesting the provision of the content. And) together with the other two multimedia content receiving apparatuses 120 and 130 and store them in the storage means. In addition, the third multimedia content receiving device 140 receives the contents (c ₂ , c ₃ ) received by the _second multicast (M ₂ ) together with the second multimedia content receiving device 120 and stores them in the storage means. Thus, the storage means stores portions of the content received in different multicasts (ie, (c ₂ , c ₃ ), (c ₅ to the end of the content)).

Meanwhile, the third multimedia content receiving device 140 receives the portions c ₁ and c _{4 that} are not received by the other multicasts M ₁ and M ₂ through the third multicast M ₃ from the time t ₂ . At this time, the third multimedia content receiving device 140 outputs the portion (c ₁ ) received through the _third multicast (M ₃ ) on the screen immediately after reception, and then receives the second multicast (M ₂ ) from the storage means. One portion (c ₂ , c ₃ ) is read out and output, and then the portion (c ₄ ) received through the _third multicast (M ₃ ) is immediately output on the screen, and finally, the first multicast (M _1). ) receiving a portion ₍₅ c below) and outputs the read out from the storage means.

FIG. 9 is a diagram illustrating a content providing process for each time zone of a multimedia content providing apparatus when a request for providing identical contents is received from four multimedia content receiving apparatuses. In FIG. 9, the content providing process related to the three multimedia content receiving apparatuses 120, 130, and 140 requesting the content is slightly delayed only at a time point t ₂ of the content providing request by the third multimedia content receiving apparatus 140. It is the same as that described with reference to FIG. 7 and FIG. 8 except for the point. Therefore, only the content providing process related to the fourth multimedia content receiving apparatus 150 that requests the provision of the same content is described.

Referring to FIG. 9, the fourth multimedia content receiving apparatus 150 transmits the content (c ₉ ) transmitted by the multimedia content providing apparatus 110 to the first multicast M ₁ at the time t ₃ of requesting the provision of the content. And) together with the other three multimedia content receiving apparatuses (120, 130, 140) and stored in the storage means. In addition, the fourth multimedia content receiving apparatus 150 receives the content c ₅ received through the _third multicast M ₃ together with the third multimedia content receiving apparatus 140 and stores it in the storage means. At this time, the second multicast M ₂ is already finished. Therefore, the storage means stores portions of the content received in different multicasts (ie, (c ₅ ) and (c ₉ to the end of the content)).

Meanwhile, the fourth multimedia content receiving apparatus 150 may not receive the _first multicast (M ₁ , M ₃ ) through the fourth multicast (M ₄ ) from time point t ₃ (c ₁ , c ₂ , c ₃ , c). ₄ , c ₆ , c ₇ , c ₈ ). At this time, the fourth multimedia content receiving apparatus 150 outputs the portions (c ₁ , c ₂ , c ₃ , c ₄ ) received through the _fourth multicast M ₄ on the screen immediately after receiving them, and then outputs them from the storage means. The part c ₅ received through ₃ multicast (M ₃ ) is read out and output, and the screen (c ₆ , c ₇ , c ₈ ) received through the fourth multicast (M ₄ ) is immediately received. And the part (after c ₉ ) received by the _first multicast M ₁ is read out from the storage means and output.

If five or more multimedia content receiving devices in the same subnetwork request the same content to be provided to the multimedia content providing device at a time difference, the method described with reference to FIGS. 7 to 9 may be extended and applied.

The invention can also be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, and may also be implemented in the form of a carrier wave (for example, transmission over the Internet). Include. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the specific preferred embodiments described above, and the present invention belongs to the present invention without departing from the gist of the present invention as claimed in the claims. Various modifications can be made by those skilled in the art, and such changes are within the scope of the claims.

According to the present invention, there is provided an apparatus and method for providing multimedia contents, and an apparatus and method for receiving multimedia contents. The multicasting of popular contents is multiplied by a transmitter and a receiver as necessary to shorten the transmission time of a server as much as possible. Can be maximized. In addition, when providing a VoD service in an IP environment, it is possible to significantly reduce the bandwidth requirement of the network and to increase the number of receiving terminals of the server that can simultaneously service the conventional technology.

Claims (9)

An apparatus for providing multimedia contents to a multimedia data receiving apparatus connected through a network, the apparatus comprising: A connection confirming unit confirming whether or not there is a second multimedia data receiving apparatus receiving the same content as the content requested from the first multimedia data receiving apparatus through the first multicast session; And And a session manager configured to transmit a part of the requested content by setting a second multicast session while maintaining the provision of the content through the first multicast session when the second multimedia data receiver exists. Multimedia content providing device. The method of claim 1, When the session management unit transmits the content portion corresponding to the time from providing the content to the second multimedia data receiving apparatus to the time of providing the content to the first multimedia data receiving apparatus, the first multimedia data receiving apparatus is transmitted. And release the second multicast session. In the method for providing multimedia content to a multimedia data receiving apparatus connected through a network, Checking whether there is a second multimedia data receiving apparatus that receives the same content as the content requested from the first multimedia data receiving apparatus through the first multicast session; And If the second multimedia data receiver exists, establishing a second multicast session while maintaining the provision of the content through the first multicast session, and transmitting a portion of the requested content from the second multimedia data receiver; Including; In the second multicast session, a content portion corresponding to a time point from when the content is provided to the second multimedia data receiver to the time point when the content is provided to the first multimedia data receiver is the first multimedia data receiver. Multimedia content providing method characterized in that is released when transmitted. A computer-readable recording medium having recorded thereon a program for executing the multimedia content providing method according to claim 3 on a computer. A content requesting unit requesting to provide the content requested from the user to a content providing device connected through a network; A content receiving unit which receives a content transmitted from the content providing device through a multicast session; A content storage unit for storing content received through a first multicast session set up before requesting to provide the content to the content providing device; And Outputs the content received from the content providing device through a second multicast session; and outputs the content received through the first multicast session stored in the content storage unit when the second multicast session is released. Multimedia content receiving apparatus comprising a; content output unit. The method of claim 5, The second multicast session is released when a content portion corresponding to the content is transmitted from the time when the content is provided to another multimedia content receiving device to the time when the content starts to be provided through the second multicast session. Multimedia content receiver. Requesting to provide the content requested from the user to the content providing device connected through the network; Receiving the content requested from the user through a first multicast session established before requesting the content providing apparatus to provide the content and storing the received content in the storage means; And Outputting the content received from the content providing device through a second multicast session, and continuously outputting the content received through the first multicast session stored in the storage means when the second multicast session is released. Multimedia content receiving method comprising a. The method of claim 7, wherein The second multicast session is released when a content portion corresponding to the content is transmitted from the time when the content is provided to another multimedia content receiving device to the time when the content starts to be provided through the second multicast session. How to receive multimedia content. A computer-readable recording medium having recorded thereon a program for executing the multimedia content receiving method according to claim 7 or 8 on a computer.

Images