KR101602280B1 - Digital set-top box based on linux os ip - Google Patents

Abstract

Disclosed is a digital set-top box based on a Linux operating system which is configured to operate a DVB set-top box based on the Linux operating system, improve security function for an additional service of a system operator by applying Zappware middleware and CONAX CAS security function, and improve needs of users. The digital set-top box based on the Linux operating system is connected with satellites, terrestrial communications line, and cables in order to receive live broadcast; forms a DVB network based on the Linux operating system; is connected with broadband interface including Internet in parallel to the satellites, the terrestrial communications line, and the cables; distributes CPU operating time for each service desired by a user by interworking with a Linux kernel scheduler; scrambles a broadcast signal and application program data which are inputted; and descrambles only broadcast signal and application program data of which license has been permitted.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital set-

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a digital set-top box, and more particularly, to a DVB set-top box operating system using a Linux-based operating system, while applying Zappware middleware and CONAX CAS security functions, And also to a digital set top box based on a Linux operating system that can be improved.

Digital Video Broadcasting (DVB) provides a standard for the distribution of digital broadcast video content. One of the issues with the adoption of DVB is that the initial digital content provided by the standard can be potentially recorded and distributed without loss of quality and without the consent of the content owner. To avoid unauthorized distribution, the DVB standard has a mechanism for encrypting the distributed content before transmission. However, DVB does not represent digital rights management (DRM) schemes or key delivery standards.

In Korean Patent Laid-Open Publication No. 2013-0130412 (published on Mar. 12, 2013), DVB DRM solutions propose a method for transmitting encryption rights to a voucher transmitted together with the same broadcast performing DVB transmission. However, this approach can be very wasteful in bandwidth because each user needs to receive an individualized authority. In particular, as the number of tokens increases, the bandwidth of the broadcast link, which will carry digital content, will be wasted unnecessarily.

Meanwhile, the set-top boxes that have been developed and commercialized have been developed and commercialized based on RTOS (Real Time Operating System). Since the set-top box based on the RTOS executes the execution command sequentially using only the memory area (kernel area) according to the operating system, high accuracy and quick response can be expected to execute the sequential execution command.

However, in recent years, the expansion of smart phones and smart devices has required hybrid services such as smart TVs and multi-application program execution functions. In addition to providing high-quality video display functions on the basis of RTOS, There was no other way. In other words, there is a limit to apply RTOS-based set-top box to smart TV or hybrid TV, which requires various functions simultaneously such as internet network function and multi-application program function.

Korean Patent Laid-Open Publication No. 2013-0130412 (published on 12.02.2012)

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide a DVB- To provide a digital set-top box based on a Linux operating system that can also improve the needs of the users.

According to an aspect of the present invention, there is provided a digital set-top box based on a Linux operating system, which is connected to a satellite, a terrestrial communication line and a cable for receiving live broadcasting, The satellite, the terrestrial communication line, and the cable are connected to a broadband interface including the Internet in parallel, and the CPU operating time is distributed according to a service requested by the user in cooperation with a Linux kernel scheduler And scrambles the input broadcasting signal and the application program data, and descrambles only the broadcasting signal and the application program data that are previously licensed.

The above-described digital operating system-based digital set-top box according to the present invention of the present invention is a Linux-based DVB set-top box that is powered by Zappware middleware and CONAX CAS security functions to enhance security functions for additional services of broadcasters, Needs also have an effect that can be improved.

In particular, the DVB set-top box of the present invention can apply a multi-kernel scheduler capable of efficiently redistributing CPU running time in cooperation with a Linux kernel scheduler, and can also assure the maximum response, and secure the license through CONAX CAS The function can be enhanced.

In addition, since the DVB set-top box of the present invention includes not only IP and DVB but also functions such as VOD function, application program execution, multi-kernel scheduler, etc., it is possible to provide a user-oriented broadcasting system.

In addition, broadcasters who apply Zappware middleware and Security CAS (CONAX) can expand the utilization of broadcasters to acquire licenses according to the system sought by broadcasters.

1 is a diagram for explaining a concept of a digital set-top box based on a Linux operating system in a digital broadcasting system.
FIG. 2 is a block diagram showing a configuration of a digital set-top box based on the Linux operating system shown in FIG. 1. FIG.
3 is an architecture diagram showing the DVB processing unit shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

It is also possible to simply change the operating system of the set-top box to the Linux operating system (Linux OS) in order for the Internet network function and the multi-application function to be executed at various times. In the Linux operating system, the process is divided into the operating system operating area (kernel area) and the user area (user area).

However, Linux operating systems on the same hardware have drawbacks that are heavier and slower than RTOSs, which can cause problems such as slow responsiveness and unnatural switching of graphics. In addition, the Linux operating system has several threads in a process that have the same priority and share memory areas, resulting in a fatal performance degradation in the overall system at run-time. Therefore, there are problems such as redesigning the thread to the Linux system.

Therefore, it is necessary to acquire the technology to improve the above problems or complications when the Linux operating system is applied. In this case, a multitasking scheduler capable of effectively redistributing the CPU running time in cooperation with the Linux kernel scheduler Multi-Tasking Scheduler) and security functions, and to ensure maximum responsiveness. In other words, Zappware middleware and CONAX CAS security functions can be applied to enhance multitasking scheduler and security functions.

1 is a diagram for explaining a concept of a digital set-top box based on a Linux operating system in a digital broadcasting system.

As shown in FIG. 1, a Linux operating system-based digital set-top box 100 is connected to a satellite 80 and a terrestrial communication line 60 and a cable to form a DVB network and receive live broadcasting. The satellite 80, the terrestrial communication line 60, and the cable are connected in parallel with the broadband interface 40 such as the Internet.

A broadcaster or application provider 20 for creating and transmitting live broadcasts selectively provides live broadcast signals and application program solutions through a predetermined communication line 60 or broadband interface 40.

The digital set top box 100 receives bidirectional communication with the application provider 20 via the broadband interface 40 after receiving the application program solution and application program information signals from the DVB network to provide a web based TV guide, Catch-up of video content, web video, on-demand video services, broadcast-independent applications such as news, weather, sports, games, voting, portal services, personalized photos, And the like.

In the Linux operating system applied to the digital set top box 100, various threads in one process have the same priority and the memory areas are shared with each other. Therefore, a web-based TV guide, interactive service, It is possible to provide various services such as content-back-up (Catch-up), Web video, on-demand video service, terrestrial broadcast and independent application, portal service, personalized photo and video content providing service.

In order to simultaneously provide the services requested by the user in multi, the CPU driving time must be effectively distributed. Accordingly, the digital set top box 100 distributes the CPU driving time according to the service requested by the user in cooperation with the Linux kernel scheduler through the Zappware middleware. Zappware middleware only selects and distributes licensed software or broadcast signals and application data from certain broadcasters on a license-based basis. Accordingly, the video, audio, multiplexed signal and application program data of the DVB (Digital Video Broadcasting) project standard can be selected and distributed on the basis of the license agreement, and can be operated and displayed. CPU run time can be distributed.

In addition, the digital set-top box 100 can enhance the security function by scrambling the broadcast signal and the application program data input by applying the CONAX CAS security function and descrambling only the pre-licensed broadcast signal and application program data . A common DVB common scrambling algorithm (CAS) restores encrypted DVB contents in a set-top box using an encryption algorithm using a service key and a security key. However, the CONAX CAS in the present invention descrambles and utilizes only video, audio, multiplexed signals and application program data of a DVB project standard of a broadcaster that is generally licensed. That is, when the CONAX CAS security function is applied, the digital set-top box 100 descrambles only the video, audio, multiplexed signal and application program data of the DVB project standard of the licensed broadcaster to generate a complicatedly encrypted service key or security key Security functions can be performed without sending and receiving operations.

FIG. 2 is a block diagram showing a configuration of a digital set-top box based on the Linux operating system shown in FIG. 1. FIG. 3 is an architecture diagram showing the DVB processing unit shown in Fig.

2 and 3, the Linux operating system-based digital set top box 100 includes a broadcast interface unit 131 for receiving and demodulating a digital signal input through a satellite 80, a terrestrial communication line 60, A DEMUX 132 for multiplexing and selectively transmitting the broadcast signal and the application program data output from the broadcast interface unit 131, and a demultiplexer 132 for multiplexing the multiplexed signal output from the DEMUX 132 into a Digital Video Broadcasting-Common Interface ), An AIT filter 144 for filtering application program information currently available in the multiplexed signals, a digital signal processor 144 for forming a DVB network and receiving a digital signal input through a broadband interface including the Internet , An IP processing unit 143 for processing the input Internet protocol, a multimedia application software A media player 144 that supports audio and video codecs, a DVB-CI standard broadcast signal, filtered application program data, and Internet protocol processed data in cooperation with a Linux kernel scheduler through Zappware middleware, And a DVB processing unit 110 for descrambling only the broadcast signal of the DVB-CI standard and the filtered application program data through the CONAX CAS security function and displaying the descrambled result by a browser.

The broadcast interface unit 131 includes at least one tuner for extracting a frequency signal of the DVB-CI standard, and at least one demodulator for demodulating digital signals inputted from each tuner. The demodulator demodulates the digital signal input from each tuner by modulating QPSK (Quadrature Phase Shift Keying) satellite, QAM (Quadrature Amplitude Modulation), VSB (Vestigial Side Band) cable and OFDM (Orthogonal Frequency Division Multiplexing) .

The DEMUX 132 multiplexes the broadcast signal demodulated and output from the demodulator of the broadcast interface unit 131 and the application program data, and selectively transmits the multiplexed signal.

The stream reception unit 145 processes the multiplexed signal output from the DEMUX 132 according to the DVB-CI standard in accordance with the CPU control of the DVB processing unit 110, thereby first canceling the reception restriction of the CAS scheme applied for user reception restriction . Here, the stream receiving unit 145 generates a transport stream (TS) for each multi-channel application program or broadcast signals, and supplies the transport stream to the CPU of the DVB processing unit 110. When a TS (Transport Stream) is generated for each multi-input application program or broadcast signal, the DVB processing unit 110 can distribute the CPU driving time by TS (Transport Stream) in cooperation with the Linux kernel scheduler .

The AIT filter unit 144 filters the application program information currently available in the multiplexed signals output from the DEMUX 132 and supplies only the currently available application program data to the DVB processing unit 110. At this time, when a plurality of application program data are input in a multi-format, a TS (Transport Stream) may be generated for each of a plurality of application programs and supplied to the CPU of the DVB processing unit 110. When a transport stream (TS) is generated for each application program that is multi-filtered, the DVB processing unit 110 may distribute the CPU drive time by as much as the transport stream (TS) of the application program. That is, in the Linux operating system, a process is divided into an operating system operating area (Kernel area) and a user area (User area). In the DVB processing part 110, The process can be divided into areas.

The broadband interface unit 141 includes at least one tuner that forms a DVB network and extracts a digital signal input through a broadband interface including the Internet, and at least one demodulator that demodulates the digital signals input from each tuner. The IP processing unit 143 processes the Internet protocol of the digital signals input through the demodulator.

The DVB processing unit 110 distributes the DVB-CI standard broadcast signal, the filtered application program data, and the Internet protocol processed data to the Linux kernel scheduler through the Zappware middleware and distributes the CPU driving time according to the service requested by the user. Then, only the broadcast signal of the DVB-CI standard and the filtered application program data are descrambled by the CONAX CAS security function and displayed by the browser.

To this end, the DVB processing unit 110 distributes the CPU driving time according to the service requested by the user in cooperation with the Linux kernel scheduler according to TS (Transport Stream) generated by the input application program or broadcasting signals by porting the Zappware middleware A CONAX CAS execution unit 112 for scrambling the broadcast signal and application program data ported by the CONAX CAS and descrambling only the broadcast signal and the application program data that have been previously licensed, An application manager 116 that controls the CPU so that an application program selected in accordance with a plurality of TSs (Transport Streams) for each application program is executed in cooperation with a scheduler, and an application manager 116 which controls the CPU to execute an application program selected from the CONAX CAS execution unit 112, And a browser 118 for displaying to the user.

The DVB processing unit 110 includes an MPEG decoder for converting a video signal and a video data stream of the DVB-CI standard into a displayable analog signal, a digital audio stream such as AC3 or MPEG to be converted into an analog audio signal or a digital audio format , An audio decoder based on the Linux operating system, and an operating system operating area (Kernel area) and a user area (User area) according to the Linux operating system and controlled by the CPU and the CPU, A memory for storing digital audio streams and application data, and an Ethernet or modem interface portion supporting bi-directional communication services.

As described above, the Zappware middleware execution unit 114 is in a state in which the Zappware middleware is ported, and the Zappware middleware selects and distributes license-approved software or broadcast signals and application program data of a specific broadcaster only on a license contract basis. Accordingly, the video, audio, multiplexed signal and application program data of the DVB (Digital Video Broadcasting) project standard can be selected and distributed on the basis of the license agreement, and can be operated and displayed. The CPU driving time is distributed.

The CONAX CAS execution unit 112 applies the CONAX CAS security function while the CONAX CAS is ported, and descrambles and uses only the video, audio, multiplexed signal and application program data of the DVB project standard of the general license approved broadcaster. That is, when the CONAX CAS security function is applied, the digital set-top box 100 descrambles only the video, audio, multiplexed signal and application program data of the DVB project standard of the licensed broadcaster to generate a complicatedly encrypted service key or security key It performs security function without sending / receiving operation.

The application manager 116 allows an application program selected in accordance with a transport stream (TS) of application program data of a DVB project standard input in multiples to be executed. Depending on the Linux operating system, the CPU can be controlled to run selected applications according to the TS (Transport Stream) in conjunction with the Linux kernel scheduler.

The DVB processing unit 110 configured as described above receives the data stream in the form of an object carousel through the stream receiving unit 145 (DSM-CC client) like the data broadcasting for the nonlinear audio / video data stream. The operation of the application for the linear and nonlinear audio / video contents is received by the DVB processing unit 110 and the DVB processing unit 110 by the media player 144, A streaming service can be provided in a customized manner through an interface with a user on a main board or a chip on which the terminal is formed.

Meanwhile, in the DVB project processing process of the DVB processing unit 110, the list and broadcasting guide information service functions and standards for the existing DVB broadcasting channels are used as they are. In the Internet protocol processing, It also uses the technology to make connections with the service.

The DVB processing unit 110 may be configured as a 1-chip, and the architecture of the DVB processing unit 110 and its peripheral components in a one-chip manner may be displayed and designed as shown in FIG. 3 have. The digital set-top box 100 proposed in the present invention can provide a user-oriented broadcasting system since it includes functions such as VOD function, application program execution, and multi-tasking scheduler as well as IP and DVB . In addition, it will be possible to expand the utilization of broadcasters applying Zappware Middleware and Security CAS (CONAX) to acquire licenses according to the system sought by broadcasters.

As described above, the digital set-top box 100 based on the Linux operating system of the present invention can operate a DVB set-top box based on Linux while applying Zappware middleware and CONAX CAS security functions, And enhance the needs of users. In particular, the DVB digital set-top box 100 of the present invention can apply a multitasking scheduler capable of effectively redistributing the CPU driving time in cooperation with the Linux kernel scheduler, maximize the responsiveness, It is possible to strengthen the security function by securing the license through.

In addition, the DVB digital set-top box 100 of the present invention can provide a user-centered broadcasting system since it includes functions such as VOD function, application program execution, and multitasking scheduler as well as IP and DVB. In addition, broadcasters who apply Zappware middleware and Security CAS (CONAX) can expand the utilization of broadcasters to acquire licenses according to the system sought by broadcasters.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the following claims And changes may be made without departing from the spirit and scope of the invention.

Claims (7)

A digital set-top box connected to a satellite and a terrestrial communication line and a cable for receiving a live broadcast,
The digital set-
A DVB network based on a Linux operating system, and the satellite, the terrestrial communication line and the cable are connected in parallel with a broadband interface including the Internet,
In addition to distributing the CPU driving time according to the service requested by the user in cooperation with the Linux kernel scheduler, it also scrambles the input broadcasting signal and the application program data, Scrambled,
The digital set-
A DEMUX for multiplexing and selectively transmitting a broadcast signal and application program data input via the satellite, terrestrial communication line, and cable;
A stream receiver for processing the multiplexed signal output from the DEMUX according to a DVB-CI (Digital Video Broadcasting-Common Interface) standard;
An AIT filter for filtering application program information currently available in the multiplexed signals; And
The DVB-CI standard broadcast signal, the filtered application program data and the Internet protocol processed data are linked with the Linux kernel scheduler through the Zappware middleware to distribute the CPU driving time for each service requested by the user, And a DVB processing unit for descrambling only the broadcast signal of the DVB-CI standard and the filtered application program data and displaying the descrambled application program data on a browser through the function of the DVB-CI standard.
delete The method according to claim 1,
The stream receiver
The multiplexing signal is processed in accordance with the DVB-CI standard in accordance with the CPU control of the DVB processing unit to thereby first cancel the reception restriction of the broadcast signal to which the CAS scheme is applied for user reception restriction, A digital set-top box based on a Linux operating system for generating a transport stream (TS) for each of the application programs or the broadcast signals input in a multi-format and supplying the transport stream to a CPU of the DVB processing unit.
The method according to claim 1,
The AIT filter unit
Wherein the DVB processing unit is adapted to filter application program information currently available in the multiplexed signals,
A digital set top box based on a Linux operating system for generating a transport stream (TS) for each of a plurality of application programs and supplying the transport stream to a CPU of the DVB processing unit when a plurality of application program data are inputted in a multi-format.
The method according to claim 3 or 4,
The DVB processing unit
A Linux operating system-based digital set top box that distributes the CPU run time for each TS (Transport Stream) in cooperation with the Linux kernel scheduler, and divides the run time into an operating system operation area and a user area in accordance with the distributed time.
The method according to claim 1,
The DVB processing unit
A Zappware middleware execution unit for distributing a CPU driving time for each service requested by a user in cooperation with a Linux kernel scheduler according to TS (Transport Stream) generated by application programs or broadcast signals;
A CONAX CAS executor for porting a CONAX CAS to scramble a broadcast signal and application program data and descrambling only pre-licensed broadcast signals and application program data;
An application manager for controlling the CPU to execute an application program selected in accordance with the transport stream (TS) for a plurality of application programs in cooperation with the Linux kernel scheduler; And
And a browser for displaying a descrambled broadcast signal and application program data from the CONAX CAS executor to a user.
The method according to claim 6,
The DVB processing unit
An MPEG decoder for decoding the video signal and the video data stream of the DVB-CI standard and converting the video signal and the video data stream into a displayable analog signal;
An audio decoder for converting an AC3 or MPEG standard digital audio stream into an analog audio signal or a digital audio format;
A CPU for controlling and controlling overall system operation by executing a process divided into an operating system operation area and a user area according to the Linux operating system;
A memory for storing a digital audio stream and application program data under the control of the CPU; And
A digital set-top box based on a Linux operating system, further comprising an Ethernet or modem interface portion supporting bi-directional communication services.

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