Method and system for content distribution

[0001] The present invention relates generally to a method and a content distribution system over a network. [0002] Various types of information can be presented in the form of digital content, including audio, video, text, images and multimedia information. Such digital content can be presented on hardware players and through computer systems that support properly configured software programs.

[0003] The convergence of technological advances in the compression, storage and transmission of digital data has led to a global communication network that allows digital content to be rapidly distributed to a large number of potential customers. At the same time, this technological convergence has made it possible that unprecedented amounts of digital content can be copied faultlessly and distributed to a large number of people. For example, users can easily exchange unprotected digital files via email or by direct file transfer over the Internet. Users can also access and download digital content posted on the website using a conventional browser application program running on a computer system.

[0004] US 5,654,747 relates to a pay-per-view content distribution system. The system includes an information network on the operator's side and at least one terminal on the client's side. The information network includes means for embedding, at the request of the client terminal, specific content in the digital data stream and sending this digital data stream to the terminal. The client terminal remembers the received content for later access by the user. At the request of access to the content by the user, the terminal first requests authorization from the information network (by checking the user's account data) before granting access to the content and after granting such access, it communicates the billing signal to the information network.

[0005] US 2001/003627 A1 discloses a video distribution system comprising a series of video anchor point networks for storing a number of video films available for rental and a number of subscriber terminals. At the subscriber's request via the subscriber's terminal, the video spot network checks whether the subscriber's terminal is entitled to receive the requested video and upon confirmation, transmits the desired video to the subscriber's terminal. When the download is complete, the video point network sends a message to the ISP that generates a billing record based on the received download information. If the subscriber attempts to play the downloaded video file, the subscriber terminal sends the authorization request to the video point of presence network. If the result of authorization indicates

[0006] Therefore, there is a need for a content distribution system that offers full identification of digital distribution content to a plurality of subscribers. Such controlled distribution is e.g. possible through a content distribution system based on the network according to claim 1.

[0007] Based on a point-to-multipoint network, the content distribution system of the present invention includes a central distribution server and a number of subscriber terminals. The central distribution server includes elements of the converter for embedding content data in the digital supply stream and transmitting elements for transmitting the indicated digital delivery stream to at least one of the indicated subscriber terminals via the transmission network channel. At least one subscriber terminal includes receiving means for receiving the indicated digital delivery stream from a designated central server and interface elements for providing access to the indicated digital delivery stream and / or content embedded therein by the subscriber. According to the invention,

[0008] In a preferred embodiment, the indicated feedback management elements further comprise means for generating a first message and a second message, respectively, upon receipt of the indicated first and second confirmations transmitted from the indicated at least one subscriber terminal to the central distribution server. These first and second messages confirm that the status of the digital delivery stream and / or the content therein deposited at at least one subscriber terminal is known by the central distribution server and that the indicated status is thus confirmed.

[0009] The present invention thus enables full traceability of content distribution via the network by generating two separate confirmations on the part of the subscriber, one after receiving the data containing the content for distribution, and also when the user accesses the content. These confirmations are sent back to the central distribution server's feedback management module, so that the receipt and access to the content delivered are fully recorded.

[0010] It will be appreciated that the content distribution according to the present invention is not limited to a particular type of network. In fact, the flow of data streamed by the central distribution server can use any type of physical telecommunications networks: LAN, corporate network, Internet (through VPN tunneling), and any cable or satellite television network. In particular, the central distribution server can handle the same delivery simultaneously on many different channels of the forwarding network (e.g. the same simultaneous transmission on both of the DSL and satellite network). In addition, the forwarding network channel for transmitting the delivery stream and the return network channel for sending confirmation to the central distribution server do not have to be of the same type. Ultimately, the content can be delivered to any suitable subscriber terminal, which can be a dedicated device or a standard computer by means of appropriate client application software to receive and access content. [0011] In a preferred embodiment of the invention, the indicated elements of the converter for embedding the content in the digital supply stream comprise at least one strimer module for converting the content in the data stream. The strimer module collects the digital content (file or stream) to be transmitted and converts it into a stream that is suitable for transmission. By converting the content, the strimer module also manages the bit rate of the content transmission. The content can be placed on any device for storing content (e.g. a computer) that is reachable by the master server.

[0012] In a further preferred embodiment of the invention, the indicated converter elements for embedding content in the digital supply stream comprise a multiplexer module, wherein said multiplexer module for converting at least two individual data streams in a mixed stream, said mixed stream comprises data packets indicated at the least two individual data streams. In this embodiment of the invention, the indicated receiving means of the indicated at least one subscriber terminal comprise a demultiplexer module for de-multiplexing said mixed stream into indicated individual data streams. The multiplexer module allows mixing (multiplexing) of two or more parallel data streams from different sources into a unique stream directed to the physical output interface. It should be noted that the multiplexing data stream may be the initial content for distribution when this content falls into the form of a corresponding stream or may be generated by one or more strimer modules that converts the content based on the file into the stream being transmitted. The de-multiplexer module on each subscriber's terminal enables the reception of the digital signal of the delivery stream and / or of given content embedded in it by the multiplexer module through the channel of the transmitting network and subsequent and separate restoration of individual recipient contents. that the multiplexing data stream may be the initial content for distribution when the content falls into the form of a corresponding stream or may be generated by one or more strimer modules that converts the content based on the file into the stream being transmitted. The de-multiplexer module on each subscriber's terminal enables the reception of the digital signal of the delivery stream and / or of given content embedded in it by the multiplexer module through the channel of the transmitting network and subsequent and separate restoration of individual recipient contents. that the multiplexing data stream may be the initial content for distribution when the content falls into the form of a corresponding stream or may be generated by one or more strimer modules that converts the content based on the file into the stream being transmitted. The de-multiplexer module on each subscriber's terminal enables the reception of the digital signal of the delivery stream and / or of given content embedded in it by the multiplexer module through the channel of the transmitting network and subsequent and separate restoration of individual recipient contents.

[0013] In order to optimize the use of available bandwidth in the network, the central distribution server preferably comprises a scheduler module for managing scheduling and scheduling content distribution. The planning program module can provide scheduling and scheduling of the delivery of the media stream whose transmission is requested. Transmission performance (satellite) is set for time periods and limited. The planning module is able to limit the total amount of data (file or stream) that can be transmitted at any given time. This will allow you to determine in advance whether the file or "stream" can be integrated with the ongoing stream of delivery.

[0014] In a preferred embodiment of the invention, the feedback management module comprises means for interacting with the indicated at least one strim- er module to cause the indicated strim- er module to again send the possible missing data when receiving the corresponding acknowledgment by the indicated at least one subscriber terminal. This embodiment provides a reliable transmission of content to be delivered as any missing data that may have been lost during transmission and will be sent again until the feedback management module receives the subscriber's confirmation that the data has been completely received.

[0015] Currently, the encryption of valuable content is becoming necessary to guarantee the maximum protection of copyright owners. Current distribution networks (DSL Internet, satellite transmission) allow users equipped with the appropriate equipment to connect (DSL modem, satellite antenna) easy and quick access to many content. Such an opportunity may become a disadvantage when it comes to limiting the accessibility of content to groups of users who are properly authorized. Only encryption mechanisms that apply to both the content itself (e.g. DRM) and when transmitted over the network can effectively protect this right. In a further embodiment of the invention, the centralized distribution server thus includes an encryption module for encrypting said data stream and / or said mixed stream to an encrypted stream and the at least one subscriber terminal comprises a decryption module decoding that the encrypted stream into an unencrypted data stream and / or unencrypted mixed stream depending on the example for decryption encrypted content data embedded in unencrypted content. In a further embodiment of the invention, the central distribution server thus comprises an encryption module to encrypt the indicated data stream and / or the indicated mixed stream in the encrypted stream, and the at least one remote terminal has a decryption module to decrypt the indicated encrypted stream in an unencrypted data stream and / or an unencrypted mixed stream and, depending on the embodiment, to decrypt embedded encrypted content data in unencrypted content data. The encryption of the data content to be embedded in the data stream prior to the transmission makes it possible to prohibit access to the stream provided by any person who has not obtained the required license to access the content. In this context, it should be noted that the content itself may be encrypted prior to conversion to the stream, and after conversion the resulting stream is re-encoded on the fly before its transmission.

[0016] Encrypting the delivery stream can be accomplished using any suitable encryption algorithm. For example, an encryption module may use the standard AES algorithm using two methods: the ECB for an electronic cookbook and CBC for Cipher Block Chaining for Coding Block Blocks with 128, 192 or 256 bits for encrypting content and stream. In a more preferred embodiment of the invention, the encryption module uses an encryption algorithm based on modulo arithmetic with encrypted private keys (e.g. 128 bits) using the ECB or CBC. In both cases, the CBC will only be used in connection with the TCP Internet protocol. [0017] On the subscriber's side, decrypting the encrypted delivery stream may be considered access to content for distribution. In this case, said second means for generating the second acknowledgment react with the indicated decryption module and generate the indicated second confirmation when decrypting the encrypted stream in an unencrypted data stream and / or unencrypted mixed stream. In another possible embodiment, if e.g. a delivery stream is formed by an encrypted mixed stream in which the content embedded in individual streams is also encrypted, decrypting the encrypted mixed stream and subsequent demultiplexing of the multiplexed stream, to reproduce the encrypted data content embedded in it be considered as part of the receipt process, and therefore only generate the first confirmation (type 1).

In a variant of the invention, the central distribution server may include a forward error module for providing the indicated data stream and / or an indicated mixed stream from the redundant coding scheme, and the receiving means of the at least one remote subscriber terminal may include a corresponding error correction module for restoring data lost during transmission based on the indicated redundant coding scheme. The forward error correction module can be applied separately to different contents, which means that the multiplexer can mix both the error corrected content and other content without error correction and that each de-multiplexer on the subscriber terminals can process the content accordingly.

[0019] Finally, the indicated central distribution server preferably comprises a monitor module for monitoring information from the indicated at least one strimer module and / or an indicated multiplexer module and / or an indicated scheduler program and / or an indicated feedback management module and / or an indicated encryption module. and / or the indicated error correction module and to control the operation of the indicated at least one strimer module and / or the indicated multiplexer module and / or the indicated scheduler program module and / or the indicated feedback management module and / or the indicated encryption module and / or the indicated correction module; mistakes.

[0020] In summary, it should be noted that the present invention relates to a system and method for distributing content from a central point (server) to a user group (client) in any telecommunications networks. Distribution is a point-to-multipoint distribution through the target channel: the distribution control information is sent back to the central point by the return channel. The return and destination channels can be any physical networks and not necessarily the same. Users can be deployed on different return and destination networks that can be simultaneously served by the system. [0021] Content distribution is in the automated control of the central distribution server. The distribution is fully managed (bandwidth optimization through planning at the central point) and supervised from end to end on the return and destination channels. The central point server can simultaneously take many input content sources (file or stream) before and distribute them to multiple output channels to target.

[0022] Tracking is performed by tracking 2 confirmations sent by the user to the central point: the first after receiving the content; second, when content is available (for example, by decryption). The invention thus makes it possible to track the delivery history e.g. for purposes such as accounting, to prevent illegal interception of content throughout the distribution chain. In addition, type 2 confirmations sent by the user to the server, and then their confirmation of receipt by the server, enhance the traceability of content delivered at any time during the transmission process.

[0023] It should be noted that the central point server system may also return a confirmation to the subscriber to confirm that the type 2 confirmation sent by the user in the return channel has been effectively received. The content can then be accessed, otherwise it is beyond the reach of users (encrypted). The server always knows the content status with accuracy on the users' websites and guarantees traceability.

[0024] In a preferred embodiment, the system provides load resistance and load balancing through a set of 6 cross-interacting but independent modules (strimera, multiplexer, scheduler, monitor, feedback management, de-multiplexer). The central distribution server preferably supports five of these modules (strimer, multiplexer, scheduler, monitor, feedback management) and the client terminal can support the de-multiplexer module that is part of the receiver, and the strimer and multiplexer module to return confirmations and any other information to the central point.

[0025] The main function of the different modules can be summarized as follows: the scheduling program module provides scheduling and scheduling deliveries to optimize performance: it allows reservation of deliveries subject to the actual availability of the network's capacity temporal. The strimer module performs one delivery item to the scheduler program command. The strimer performs the encryption of the content itself, if necessary, and if required, processing the error correction of the target content. The strimer transmits the data flow to the multiplexer module that performs in-flight encryption on the output mixed stream. The de-multiplexer module decrypts in-flight the mixed stream produced by the multiplexer, restores the individual stream from the mixed stream; purchases data packages from an individual stream, checks, whether the content embedded in it is authorized, and if so restores the initial content; sends back related acknowledgments (reception and decryption) via the return channel until confirmed by the server.

[0026] The acknowledgment of receipt is automatically sent by the de-multiplexer to the central distribution server. Confirmation of decryption can be automatically sent (in this case, the content is automatically decrypted upon receipt via a procedure passed from the content and performed after receipt) or sent when the user requests on demand decryption of the content (in this case, the de-multiplexer provides the user interface) . The monitor module collects monitoring data from other modules without direct interaction (exchange goes to the FC_IMonitor monitoring module - I means the library - which is associated with all monitored modules). The feedback management module will receive acknowledgments from the user demultiplexer module,

[0027] It should be noted that the distribution in a set of 6 independent cross-acting functions provides strength to prevent the distribution process from halting when one function fails, and load balancing to adapt to simultaneous load variations, thereby ensuring reliability of content transmission. For example, if the scheduler module stops, then the delivery reservation is no longer possible; but ongoing delivery is still ongoing and supervision is still active (failure of the planning program module is known). If one of the strimer modules stops, only the supply associated with this strimer module stops; all other deliveries are continued and supervision is still active (especially that the failure of the strimer module is known). If the multiplexer module stops, this distribution stops, but distribution reservation is still possible. The supervision also remains active (the failure of the multiplexer module is known), especially on the associated target channel network. Each case of the multiplexer module is released by the second one. If the de-multiplexer module stops, the user can not receive any content; but the content has already been received and not confirmed by the server is still not available, and therefore protected. If the monitor module stops, then supervision is no longer possible, but the reservation and delivery remain available. Content tracking and protection are preserved. Finally, if the feedback management module stops, it is no longer possible to confirm the receipt of the content (or retransmission of possibly lost data) or access to the content. Content tracking and protection are maintained. Reservations, delivery and monitoring are still available.

[0028] It should be noted that modules corresponding to 6 functions can be distributed on separate computers that can be connected via LAN or WAN without changing the functioning of the distribution. In addition, the amount of work required to simultaneously acquire several content sources can be divided into different cases of the strimer module. Finally, multiple output channels (terrestrial, satellite, 3G ...) can be managed by various cases of the multiplexer module. Numerous examples of the multiplexer module (several multiplexer processes) can be used for 2 reasons: 1. In order to provide redundancy in the event that one multiplex process fails and stops, 2. To enable multi-stream distribution on individual multiple physical network channels from one source of content after purchasing it.

[0029] In preferred system embodiments, the protection is implemented in a symmetric double encryption scheme, where both the content itself is encrypted and its in-flight delivery stream. It is possible to select a group of subscribers for whom the reception of a given content is provided. The stream is encrypted on the fly for all users and the specific content sent in the stream to the group of authorized users can be encrypted once again (a double symmetric encryption scheme based on private keys). Users can be authorized by initial transmission of a private key (so-called Content Access Key - CAKi for content of rank and) to receive and access certain content (content of rank and). The private key is itself encrypted and stored in an encrypted form on the subscriber's terminal. The content of the rank and was acquired by the terminal if and only if CAKi is present; otherwise it will not be rejected by the demultiplexer. The private key is used when it comes to accessing certain content (decryption) and to decrypt content: the private key is previously decrypted by the decryption key which itself is encrypted. The users' decryption keys can be periodically updated and confirmation of the update can be sent to the central server. the private key is previously decrypted by the decryption key which itself is encrypted. The users' decryption keys can be periodically updated and confirmation of the update can be sent to the central server. the private key is previously decrypted by the decryption key which itself is encrypted. The users' decryption keys can be periodically updated and confirmation of the update can be sent to the central server.

[0030] The content distribution method disclosed above is believed to provide an optimal approach with regard to defining and implementing a fully centralized, controlled, secure and supervised content distribution strategy in which the central distribution server decides and organizes all activities. This method guarantees the protection of copyright owners when it comes to the distribution of valuable content. This method implements real-time bandwidth optimization by managing bandwidth at the central point which is subject to delivery restrictions and bandwidth availability.

Detailed description with reference to figures [0031] The present invention will be better understood by the following detailed description of a non-limiting exemplary embodiment with reference to the accompanying drawings in which

Fig. 1: shows a general view of an embodiment of a terrestrial content distribution system;

Fig. 2: shows a general view of an embodiment of a content distribution system based on a satellite network;

Fig. 3: shows a dynamic bandwidth allocation for content transmission;

Fig. 4: shows the interaction of several modules from the scheduler;

Fig. 5: shows different ways to acquire content;

Fig. 6: shows the principle of media separation into blocks;

Fig. 7: shows a block mixing process;

Fig. 8: shows the architecture of the strimer-multiplexer interface;

Fig. 9: shows block encryption and decryption;

Fig. 10: shows the permutation of blocks after interleaving;

Fig. 11: shows the operation of restoring lost blocks;

Fig. 12: shows the initial reproduction action of individual streams;

Fig. 13: shows the principle of the return channel re-transmission process.

[0032] Figures 1 and 2 show a general view of two embodiments of a content distribution system in which digital content is provided to a subscriber group, via a standard terrestrial network (Figure 1) or via a satellite network (Figure 2). In both embodiments, the system includes a number of modules that interoperate to provide secure and reliable transfer of content to individual subscribers: FC_pSCHEDULER scheduler scheduler (1) (resource manager) - where p means the process processes the delivery requests and performs the reservation. Manages bandwidth, schedules transmissions with respect to time constraints in accordance with the delivery requirements. A strimer module or group of FC_pSTREAMER stringer modules (2) receives and transmits one stream to the FC_pMUX multiplexer module (4).

[0033] The FC_pMUX multiplexer performs mixing (multiplexing) of simultaneous data streams coming from several sources (and associated strimer modules) to a unique mixed stream directed to the physical output interface. The FC_ICRYPT encryption library module (5) is associated with FC_pMUX and encrypts the mixed stream so that it remains unavailable to unauthorized receivers (or listeners). On the subscriber's or client's side, the de-multiplexer module or the FC_pDEMUX receiver (6) registers data to which it has been authorized from the interface; decrypts (inverse FC_ICRYPT) in a mixed stream flight, de-multiplexes and decodes (reverse FC_IFEC), and finally restores the original content.

[0034] The FC_pBACK (7) feedback management module is responsible for receiving and processing all confirmation information coming from reverse channels (client feedback link to the server if available), such as file reception and decryption confirmation of the file.

[0035] The FC_pMONITOR monitor module (8) provides real-time supervision of the end-to-end supply chain. He is responsible for collecting monitoring information from various modules and managing reporting of information provided by the FC_pBACK module.

Finally, the FC_sADMIN web-based administration interface - where s is a screen allows administrators to organize, manage and monitor their various content distribution scenarios to users: delivery information, such as content type / location, receiver groups, authorizations, scheduling, time intervals, reporting of deliveries and pickups by users.

[0037] Detailed information about the different modules: FC_pSCHEDULER (1) FC_pSTREAMER (2), FC_IFEC (3), FC_pMUX (4), FC_ICRYPT (5), FC_pDEMUX (6), FC_pBACK (7), FC_pMONITOR (8) and their the operation below will be described in the following:

1. FC pSCHEDULER [0038] FC_pSCHEDULER provides higher scheduling and scheduling of media supplies that are requested for transmission. Transmission performance (satellite) is set for time periods and limited. The scheduler is able to limit the total amount of data (file or stream) that can be transmitted at any given time. This will allow you to determine in advance whether the file or "stream" can be integrated with a continuous stream of delivery.

[0039] Two basic content categories are considered: a) file (movie, document ...) whose transmission rate assigned by the scheduler will depend on the start date of the transmission and the end date in which the content is delivered to the subscriber and b) the stream ( in real time), whose transmission rate is determined at the start of transmission.

[0040] The content manager makes a file transfer reservation: FC_pSCHEDULER will calculate the bandwidth that is required to deliver the file on the end date and will or will not accept the booking considering the available bandwidth during that time period.

[0041] The files offer the greatest scheduling flexibility because they allow real-time modification of the transmission rate to enable simultaneous transmission of additional content (file or stream) within bandwidth constraints and in accordance with the requirements of delivery time. On the other hand, the speed of the stream transmission can be adjusted in such a way, because the streams require a constant (non-variable) rate during the entire transmission.

[0042] Fig. 3 shows the dynamic band allocation for content transmission. The example shows how the current file transfer rate (in black) can be lowered to allow a new file (dark gray), whose delivery time is shorter, by taking over the transmission band. It is noted that the (light gray) bit rate can not be modified during diffusion but when it ends (or is interrupted), the bandwidth is released and made available and serves the next transmissions.

[0043] The FC_pSCHEDULER process is attached to a unique target channel network. The FC_pSCHEDULER process organizes transmissions subject to delivery restrictions and manages the capacity for the FC_pMUX process that sends one mixed stream through the target channel network. For a given target channel network, there is one and only one FC_pSCHEDULER and FC_pMUX process. Each data stream produced by the FC_pSTREAMER process has its delivery time limits to which the FC_pSCHEDULER calculation applies.

[0044] FC_pSCHEDULER will first request from the media FC_pMUX whose transmission is in progress, and then from the media database to be transmitted in the future. Based on these responses, general calculation of the delivery schedule can be made. While adhering to the general rules of media delivery planning, FC_SCHEDULER launches FC_pSTREAMER, which downloads media and forwards it to FC_pMUX.

2. / ^ CpSTREAMER [0045] FC_pSTREAEER collects media (file or stream) to be transmitted and organizes it for FC_pEUX. It also manages the content transmission rate. The content can be on any computer that is reachable by the strimer server (see Fig. 5). It can be downloaded by:

a) the name of the file in the LL \ N network (possibly via NFS).

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c) aZrre (PI TCP TCP port) (γζΖο ρ ^ ζζ ^ / Ί-θζιζ) strL ^^ and (^ r ^ ic ^ v ^ c3 TCP.

d) the UDP port sgdie Take away (Ευηηιεη ^ ο UDP sossanie przekazann.

[0046] In order to determine the initial content stream in a multiplexed stream, channel ID (logic) identifier is assigned by FC_pSTREAEER.

[0047] Communication between the FC_pSTREAEER and FC_pEUX processes at the heart of the server system.

FC_pSTREAEER prepares and generates a single stream that is to be mixed with other single FC_pEUX streams (see Fig. 6). This preparation consists of three stages: a) delivering a header packet that contains all content properties and rules for content processing on delivery by FC_pDEEUX (receiver). b) "dividing" the initial content into fixed-size packets for multiplexing c) controlling the stream stability to FC_pMUX in such a way that the transmission rate remains constant.

[0048] The header packet may optionally be retransmitted (carousel): this is necessary for content streamed in real time (radio channel, for example) when the receiver has not listened at the beginning of the transmission and has not received the frame header packet. FC_pDEMUX must pick up this header package and process it so that it can capture the radio signal. [0049] An important feature of the packet header is to provide dynamic modification of the stream type. The file-based content can actually be converted to streamed content to the receiver. Conversely, stream-based content can be stored as a file on the receiver. This strong functionality can be used to implement the content record and increase the overall security system.

3. FCIFEC (FEC Corrective Coding) [0050] Physical network infrastructures, though continuously improved, can not always provide a signal of excellent quality. This is not always a question of network devices: for example, in extreme conditions, such as violent thunderstorms or satellite to cellular networks, the physical signal of data transmission can be disturbed for short periods of time. Increasingly, collisions of packets due to traffic jams may result in the loss of data (packets).

[0051] In order to compensate for this situation primarily with UDP, the current content distribution system implements in real time dedicated unnecessary coding (Forwarding Error Correction) to amplify the signal and optimize the reception quality. Even if the signal is interrupted for a short period of time, the system will re-establish potentially lost data so that the end-user does not experience deterioration in the transmission quality. [0052] In a preferred embodiment, the FC_IFEC library module introduces the original technique, so that the FC_pDFMUX (receiver) does not feel the operation of these transmission errors hot. The FC_IFEC library module provides the data stream produced by FC_pSTREAMER with a redundant coding scheme that will make it resistant to short signal fades.

[0053] The stream (generated by FC_pSTREAMER after FC_IFEC application) will be supplemented with redundant information after two actions: first, calculating "Exclusive OR" XOR on frames and matrices, secondly, the blocks within the matrix group are re-arranged (interleaving for a period of time will be determined in accordance with specific parameters). The frame is made by a set of blocks (usually 8). For each frame, the XOR block (the calculation is made on all the blocks of the frame) is placed in the stream. The matrix consists of a set of frames (usually 8). Each XOR block of the matrix (corresponding to the calculation of the diagonal elements of the matrix) is inserted into the stream. The matrix group is combined with as many matrices as the number of columns inside the matrix (usually 8). If and this is the block column index,

[0054] Fig. 10 illustrates an example of a correction coding technique performed on 4-block frames and a 4-matrix group. Colored blocks show positions before and after coding

FC_IFEC. The obtained results show the first two coded matrices.

[0055] The specified XOR (odd) blocks have changed their position (the XOR blocks of matrix 2 are closed for those with matrix 0, those with matrix 3 to those with matrix 1 ...). If any loss occurs during transmission, only half of the matrix correction blocks will be lost. The coded stream that is generated corresponds to the block packet: 0, 16, 32, 48, XOR 0, XOR 17, 4, 20, 36, 52 ...

4. FCpMUX (multiplexer) [0056] FC_pMUX aims to mix different single streams produced by FC_STREAMER processes to generate one stream containing all meta delivery and media content data (see Fig. 7).

[0057] FC_pMUX also controls the flow rate that is generated and adapts it to the available bandwidth provided by the cable company, ISP or satellite operator. One of the important functions of FC_pMUX is interaction with FC_pSCHEDULER, so that bandwidth allocation to different media delivery requests is optimized. [0058] Fig. 8 shows that 2 types of content (file and stream) can be mixed into a unique stream: in fact, content output from FC_pSTREAMER is always streamed.

[0059] Individual modules of the central distribution server can be run on distributed systems with different OS: Windows NT / 2000 / XP and 2003 Server, Linux (SuSE, Mandriva, RedHat ...).

5. FCICRYPT (encryption / decryption) [0060] Currently, the encryption of valuable content is becoming necessary to guarantee maximum protection of copyright. Current distribution networks (DSL Internet, satellite transmission) allow users with appropriate equipment to connect (DSL modem, satellite antenna) easy and quick access to many content. Such possibilities may become a disadvantage when the question arises to limit the accessibility of content to groups of users who are duly authorized. Only encryption mechanisms that apply to the content itself (e.g. DRM) and during transmission over the network can effectively protect this right. [0061] The FC_ICRYPT library module provides an innovative and very secure encryption on-the-fly transmission system using coding algorithms based on modulo arithmetic (such as RSA or El-Gamal) to the stream. The FC_ICRYPT library module is applied to the multiplexed output stream produced by FC_pMUX with the associated target channel network.

[0062] In a preferred embodiment, the encryption method is based on a private key system. The same key is used for encryption and decryption. The rule is to split the stream into 32-bit blocks (4 bytes) and apply each block (called m for message-content) a series of transformations according to the parameters that are the key to producing c encrypted code.

[0063] The key is made up of a group of 8 16 bits (a total of 128 bits). Each number represents the prime number (pi as the i-th number). 32 bits are included in the range [FFD3889F, FFFFFFFB] (hexadecimal values). It's 2¹⁶ = 65536 prime numbers in this range. Full encryption is performed for 8 repetitions. Iteration and uses the number pi, and varies from 1 to 8. We notice you as the result of the i-th iteration of the encryption with:

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[0064] The final step of encryption corresponds to c = c8. The full benefit of the encryption scheme comes from the impossibility of finding mzc, without knowing pi, p2 ... ps, which is the key.

[0065] Fig. 9 shows an example of an encrypted internet delivery stream. Only receiving clients with a secret decryption key can restore the original message. A middle-of-the-road spy would not be able to view and steal data. The decryption simply involves the use of reverse cipher transformation data blocks. We start 8 iterations to the finish line with the 1st, and change from 8 to<a name="caption1"></a>C. = C? '²(mod p) andc₃= C.

1. In each iteration we calculate 1-1 '' The final decryption stage gives what creates m.

6. FCpDEMUX (receiver) [0066] The role of FC_pDEMUX is a) decoding on the fly of a mixed stream generated by FC_pMUX (via inverse function FC_ICRYPT); b) restoring from the mixed stream an individual stream built by FC_pSTREAMER: The case execution (thread) is associated with each individual stream; c) correction of transmission errors (via the inverse function FC_IFEC, when applicable to an individual stream): this is done by each thread; d) acquisition of data packets from individual streams; checking if the content embedded in them is authorized, and if so restoring the initial content; e) return to FC_pBACK (feedback management module) confirmation of content receipt as well as confirmation of access to content, when the content is made available to the user (automatically or after the user's request) after decrypting it; f) performing the procedure at the subscriber's terminal.

[0067] The reception stream may not include all blocks that have been emitted. The FC_IFEC library module handles this situation. Because of the encoded data stream generated by FC_IFEC (in addition to FC_pSTREAMER) after interleaving, missing blocks if they are distributed to blocks of entire content. The calculations made on the XOR blocks will allow you to restore (restore) the missing blocks.

[006s] Fig. 11 shows an example of error correction. Let us assume that light gray blocks have not been transferred to the receiver. Thanks to the permutation, these initial blocks corresponding to the missing one were spread over a group of matrices. XOR blocks take up the missing space: XOR calculations from other blocks allow you to restore lost blocks. The example shows that permutation of XOR blocks is the key to the efficiency of the correction mechanism. In fact, without permutation, all the first matrix correction blocks (in particular the XOR 1, 3, 5 and 7 blocks) would be in the same places as the XOR blocks 17, 19, 21 and 23, respectively), and the correction would not be possible.

[0069] The stream that is received is encrypted (by AES or by the encryption module) to ensure complete protection of the data content. The decryption mechanism (through the reverse function of FC_ICRYPT) uses a private key. This key is itself encrypted with AES or the encryption module technique and stored in encrypted form on the receiver's hard disk.

[0070] For the key to be useful, the local system identification / authentication releases the encryption key, restores the key in the central memory, and starts the decryption process of the stream.

[0071] The frame header package from one stream generated by FC_pSTREAMER contains specific information to be transmitted to the receiver, which receiver will tell how to process the content. The FC_pDEMUX module will store this information to restore the original single streams.

[0072] Fig. 12 shows how FC_pDEMUX restores the original single streams from a mixed stream. It can be seen that a light gray stream (initially file content) can be transformed into streaming content after the demultiplexer modifies the frame packet header. It is a powerful functionality of the delivery technology to change the content type to another upon receipt.

7. FCpBACK [0073] Moduł ten zarządza wszystkimi potwierdzeniami informacji pochodzących z kanałów powrotnych (link powrotny klient do serwera jeśli jest dostępny), takich jak odbiór pliku i podziękowania deszyfrowania pliku.

[0074] Despite the FC_IFEC mechanisms implemented by the technology, in order to increase the robustness of the delivery process to signal interference, it may still happen that in some cases data packets are lost during transmission. To resolve this situation, if the return channel is available, FC_pBACK receive a full reporting of possibly lost data during transmission. It interacts with FC_pSTREAMER to initiate the re-transmission of any missing data (see also Fig. 13). [0075] The files to be delivered are divided into packets by FC_pSTREAMER, which sends them to FC_pMUX. Each of these packages is individually identified and tracked so that FC_pDEMUX (receiver) can download them one by one.

[0076] FC_pBACK requests FC_pSTREAMER for retransmission of missing packets. FC_pDEMUX will wait for these packages to completely restore the original file. Such a process may take some time, in which intermediate packages are kept by FC_pDEMUX on an ongoing basis. The termination process for overdue time is carried out. When the file is completely complete and received, then FC_pDEMUX will send a confirmation to FC_pBACK. Fig. 13 shows an example of a satellite transmission to FC_pDEMUX. For some reasons (not necessarily related to satellite signal quality, which is quite good, but for example due to some network devices - switch, IP / DVB housing ... - which randomly lose frame packets), packets 2, 4, 5 will not be received in the first implementation. This information will be transferred by FC_pDEMUX to FC_pBACK via the satellite return path. FC_pBACK will then ask FC_pSTREAMER to resend the packets in the second attempt. The process ends when all packets are received or after the time limit expires depending on the operating parameters.

8. FC pMONITOR [0077] FC_pMONITOR is responsible for implementing supervision of the end-end delivery system. Its task is to gather real-time monitoring information from various modules without direct interaction (exchange goes through the FC_IMonitor monitoring library module which is connected to all modules) to be displayed on the FC_sADMIN administration interface.

[0078] The supervision interface collects the following control panel indicators in the GUI: a) from FC_pSTREAMER: emitted byte volume, medium type, medium identification (name or port and IP address), bit rate. b) with FC_pMUX: emitted byte volume, channel number, bit rate. c) with FC_pSCHEDULER: bandwidth allocation status. d) from FC_pDEMUX (via reverse link if present): confirmation of receipt of files, confirmation of file decryption, packet loss indicator per reader.

[0079] Only file-based content (movies, music, documents, programs ...) may require automatic re-transmission of specific data packets. Indeed, stream-based content is processed in real time by the recipient and the lost information does not have to be retransmitted because it would be delivered too late. Actual content based on the stream uses FC_IFEC technology for real-time corrections.

Summary of the benefits of the system [0080] The main benefits of the structure described above can be summarized as follows:

the proposed technological objectives ensure full service delivered to the turnkey packaged to carry out all activities, from planning to content acquisition, encryption and delivery with advanced options for the administration and accounting system.

The service package consists of secure, reliable, fully managed, end-to-end, multicast, unicast, worldwide, for the time of encrypted content delivery via any network (multipoint, point-to-point, satellite, terrestrial, cellular) , hybrid) all with a fully centralized web-based system with prior art user interfaces.

[0081] In order to establish protection against piracy, the delivery platform performs a dual encryption system: the content file (from DRM where required) is encrypted, and the data stream for the transfer of content is itself encrypted on the fly. The authorized recipient then decrypts the stream: the receiver then de-encapsulates the data and restores the encrypted file as it was created before the transmission.

[0082] The technology guarantees traceability of the end-to-end circulation of the encrypted content. [0083] The proposed technology allows the transmission of all types of file content (data, audio, video, binary and others) and all types of streaming content (data, voice, digital radio and television and others). The delivery process can be operated in 3 ways: • in point-to-point mode using the unicast TCP protocol. Each receiving user is directly connected to the server • by pointing to a server supported with UDP Unicast protocol. Each user receives a unique UDP stream • from the multicast UDP protocol. Each user receives a UDP stream shared by each listening user.

[0084] All of these different delivery modes may be combined to obtain a flexible stream to correspond to single or multiple data transmission strategies irrespective of the protocols and telecommunications networks used or its requirements.

[0085] The pipeline content is encrypted on the fly and then decrypted in real time by the receiving user. Each user is identified by a unique addressing system and his rights agreements or licenses grant him access to authorized content (files or streams): this list can be dynamically updated either by the user or centralized by the content owner / operator. Digital rights: The new technology implements on the server side and on the client side a comprehensive content access key system that connects through the interface with DRM to protect content and its limited use, as well as with SMS (Subscriber User Management Systems) that manage authorizations. This key management system allows the system operator, to open (and / or close) the user's right to receive content (in whole or in part), as well as the right to sell content. When the rights are deleted (at the request of the content owner), then the content becomes absolutely inaccessible to the user. [0087] Multiplexing: The current streaming system allows simultaneous transport of different types of content (organized in logical channels) at the same time, regardless of how they are delivered (TCP / IP, unicast UDP, multicast UDP). It is therefore possible to obtain a file or full directory when listening to a streaming radio channel or watching a streaming video. The supply chain can dynamically mix (multiplex) several sources of the initial content into a unique data stream, and then restore them upon receipt.

[0088] Networks: The streaming data flows generated by the distribution server can use any type of physical telecommunications network. The server can provide secure and substantial data streams directly to the LAN, company network, Internet (via VPN tunneling), and any cable, satellite or WIFI network. [0089] Subscriber's terminal: The receiver software can be integrated with many different terminals (PC, set-top box, PDA, mobile phone ...) regardless of the delivery network.

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