WO2008105568A1 - Procédé de programmation de service de diffusion numérique - Google Patents

Procédé de programmation de service de diffusion numérique Download PDF

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Publication number
WO2008105568A1
WO2008105568A1 PCT/KR2007/001036 KR2007001036W WO2008105568A1 WO 2008105568 A1 WO2008105568 A1 WO 2008105568A1 KR 2007001036 W KR2007001036 W KR 2007001036W WO 2008105568 A1 WO2008105568 A1 WO 2008105568A1
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WO
WIPO (PCT)
Prior art keywords
objects
carousel
hot
cold
broadcastings
Prior art date
Application number
PCT/KR2007/001036
Other languages
English (en)
Inventor
Sang Hyuk Kang
Sujeong Choi
Original Assignee
University Of Seoul Foundation Of Industry Academic Cooperation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by University Of Seoul Foundation Of Industry Academic Cooperation filed Critical University Of Seoul Foundation Of Industry Academic Cooperation
Priority to PCT/KR2007/001036 priority Critical patent/WO2008105568A1/fr
Publication of WO2008105568A1 publication Critical patent/WO2008105568A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
    • H04N21/435—Processing of additional data, e.g. decrypting of additional data, reconstructing software from modules extracted from the transport stream
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
    • H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
    • H04N21/235—Processing of additional data, e.g. scrambling of additional data or processing content descriptors
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
    • H04N21/25—Management operations performed by the server for facilitating the content distribution or administrating data related to end-users or client devices, e.g. end-user or client device authentication, learning user preferences for recommending movies
    • H04N21/262—Content or additional data distribution scheduling, e.g. sending additional data at off-peak times, updating software modules, calculating the carousel transmission frequency, delaying a video stream transmission, generating play-lists
    • H04N21/26266—Content or additional data distribution scheduling, e.g. sending additional data at off-peak times, updating software modules, calculating the carousel transmission frequency, delaying a video stream transmission, generating play-lists for determining content or additional data repetition rate, e.g. of a file in a DVB carousel according to its importance

Definitions

  • This invention relates to a digital broadcasting scheduling method, and more particularly, to a digital broadcasting scheduling method which is capable of reducing user waiting time and broadcasting data desired by a plurality of clients as much as possible by reflecting clients' requests on a broadcasting schedule in carousel-based digital data broadcasting.
  • a one-way digital broadcasting service refers to broadcasting data, which are set by a server, from the server to clients one-sidedly according to a fixed rule, while a two-way digital broadcasting service refers to broadcasting data satisfying a plurality of clients, which are selected by a server that reflects clients' requests on the data.
  • a server that reflects clients' requests on the data.
  • a digital broadcasting service has generally two scheduling methods.
  • a first method is a periodic broadcasting scheduling that broadcasts set data objects periodically in a fixed order
  • a second method is an on-demand broadcasting scheduling that broadcasts the most suitable data object at every point of time when a data object is broadcasted according to a client's request.
  • the periodic broadcasting scheduling may be applied to both of the one-way digital broadcasting service and the two-way digital broadcasting service while the on-demand broadcasting scheduling may be applied to the two-way digital broadcasting service.
  • the on-demand broadcasting scheduling reflects waiting time of clients' requests, deadline of data objects desired by clients, the number of clients' requests, and so on.
  • the periodic broadcasting scheduling has a problem in that it does not consider clients' requests since a server broadcasts data objects repeatedly according to a schedule set by the server one-sidedly.
  • the on-demand broadcasting scheduling has a problem in that waiting time of clients' requests becomes lengthened or no data object may be broadcasted although schedules may be changed.
  • the present invention provides a carousel-based digital broadcasting scheduling method including the steps of: comparing a request ratio with a reciprocal of the total number of data objects based on requests received from clients and recorded in a server and classifying the data objects into hot objects and cold objects; determining the number of times of broadcastings of the hot objects and priority of the cold objects; determining the cold objects to be included in a carousel depending on the length of the hot objects according to the determined number of times of broadcastings of the hot objects and the length of the carousel; determining instance spaces in which the hot objects are arranged by the determined number of times of broadcastings of the hot objects; and arranging the hot objects and the cold objects in slots of the carousel according to the determined instance spaces and broadcasting.
  • the step of classifying the data objects into the hot objects and the cold objects comprises classifying objects having an outstanding request.
  • the carousel-based digital broadcasting scheduling method further includes the step of rearranging and indexing the hot objects in an descending series of the request ratio.
  • //] ⁇ , *7 ⁇ where, f, is the number of times of broadcastings of the hot objects, f; riB, ⁇ is a request ratio, B is the length of a carousel, U represents the upper limit of the number of times of broadcastings of the hot objects, and [] means rounding off.
  • the step of determining the cold objects to be included in the carousel includes: comparing the addition of 1 to the sum of numbers of times of broadcastings of the hot objects with the length of the carousel; calculating the number of cold objects, wherein the calculated number of cold objects with adding 1 to the sum of numbers of broadcastings of the hot objects is equal to or smaller than the length of the carousal if the addition of 1 to the sum of numbers of times of broadcastings of the hot objects is equal to or smaller than the length of the carousel; and determining the cold objects according to the priority by the calculated number of cold objects.
  • the number of cold objects arranged in the carousel is 0.
  • the priority of the cold objects is determined in an descending series of the product of the request ratio and waiting time of an outstanding request.
  • the instance spaces in which the hot objects are arranged are determined according to the following equation: where, d j is an instance space of a hot object, B is the length of a carousel, and fj is the number of times of broadcastings of hot objects.
  • the carousel-based digital broadcasting scheduling method further includes the step of, if there exists an empty slot in the carousel after the hot objects and the cold objects are arranged in the slots of the carousel, randomly selecting a non- outstanding object and arranging the selected non-outstanding object in the empty slot.
  • the data objects can be evenly broadcasted with high success probability and short response time.
  • the present invention has an advantage of reduction of waiting time of the clients while satisfying the clients by selecting, programming and broadcasting desired objects with specified broadcasting periods.
  • the present invention has another advantage in that channels can be prevented from being wasted due to indiscriminate broadcasting of objects without distinguishing between high preference objects and low preference objects even though different clients desires different objects, and objects can be evenly scheduled such that waiting time of clients is not lengthened even when the number of requests increases greatly as in an on-demand-based broadcasting system other than the carousel-based broadcasting system, and only specific objects having high priority are not continuously and repeatedly broadcasted, and thus, opportunity to broadcast other objects is not lost.
  • FIG. 1 is a view illustrating an example of a digital broadcasting system to which the concept of the present invention is applied.
  • Fig. 2 is a flow chart illustrating a digital broadcasting scheduling method according to an embodiment of the present invention.
  • Figs. 3(a) to 3(d) are graphical views showing success probability for a scheduling method depending on variations of the average number of received requests per second and the total number of data objects when skew values are varied.
  • Figs. 4(a) to 4(d) are graphical views showing response times for a scheduling method depending on variations of the average number of received requests per second and the total number of data objects when skew values are varied.
  • Figs. 5(a) and 5(b) are graphical views showing response time and success probability, respectively, depending on the average number of received requests per second and the total number of data objects when an upper limit value U of the number of times of broadcastings of hot object is changed.
  • Figs. 6(a) and 6(b) are graphical views showing response time and success probability, respectively, depending on a scheduling method when the maximum waiting time P of a client is changed.
  • An object refers to various kinds of data files such as images, texts and so on to be broadcasted through data broadcasting
  • a request refers to sending information related to preference to a specific object from a client to a server
  • a carousel refers to a set of objects broadcasted at specified periods.
  • the present invention relates to updating the carousel. Accordingly, the carousel may be varied in its length, but its maximum length does not exceed B.
  • the total number of data objects is N and the carousel length is B.
  • the length of a data object is fixed to 1. (B and 1 are represented in the unit of time.)
  • response success probability is defined as a ratio of total requests to successful requests, and average lapse time until an object is broadcasted after a request to the object arrives at a server is defined as response time.
  • a request ratio ri is defined as follows.
  • a request of the requests recorded in the server, which is not yet broadcasted and is waiting in the maximum time P, is defined as an outstanding request.
  • W is defined as waiting time of the earliest arrived outstanding request of requests to the specified object i.
  • a hot object is defined as an object having values larger than 1 /N (N : the total number of objects) and a cold object is defined as an object having values smaller than 1 /N (N : the total number of objects).
  • Fig. 1 is a view illustrating an example of a digital broadcasting system to which the concept of the present invention is applied.
  • a digital broadcasting system to which the concept of the present invention is applied includes a back channel from clients 102 to a server 101.
  • the clients 102 transmit requests 103 to a mobile communication network, and the server
  • the 101 stores the requests 103 received from the clients 102 in its own queue and reflects the requests on a broadcasting program to be broadcasted to the clients 102.
  • Fig. 2 is a flow chart illustrating a digital broadcasting scheduling method according to an embodiment of the present invention.
  • a request ratio V 1 is equal to or larger than a reciprocal (1/N) of the total number (N) of data objects and there is an outstanding request
  • the objects are included in a set of hot objects
  • the request ratio ⁇ is smaller than the reciprocal (1/N) and there is an outstanding request
  • the objects are included in a set of cold objects. That is, the data objects may be classified into the set of hot objects and the set of cold objects depending on the request ratio ⁇ (S21).
  • This method is a scheduling method for an on-demand broadcasting system using requests of the clients. Accordingly, there is a need to first consider objects with an outstanding request rather than to broadcast objects with no outstanding request at a point of time of scheduling calculation (carousel start).
  • the set of hot objects A h and the set of cold objects A c are defined as follows.
  • the number of elements in the set of hot objects A h is defined as N A and the number of elements in the set of cold objects A c is defined as N A .
  • the elements in both sets are rearranged in order to determine the broadcasting priority of the cold objects and the number of times of broadcastings of the hot objects (S22).
  • the elements in the set of hot objects A h are arranged in an descending series of r h that is, r x r 2 ,- --, r Nh .
  • Table 1 shows an example of a carousel constructed according to the above first method. As shown in Table 1, if the carousel length B is 12 and the total number N of data objects is 20, hot object 1 is arranged three times at every four instance spaces and hot object 2 is arranged two times at every six instance spaces. Then, cold objects are sequentially arranged in empty slots of the carousel according to priority.
  • the hot object 2 has to be assigned to slots 1 and 7 at every six instance spaces. However, since the slot 1 has been already occupied by the hot object 1, the hot object 2 is assigned to the next empty slot 2.
  • the slots 1, 5, 9, 2 and 7 of the carousel are determined by the hot objects 1 and 2, and cold objects are arranged in the remaining slots 3, 4, 6, 8, 10, 11 and 12 according to priority.
  • objects having no outstanding request are randomly selected and included in the carousel. For example, object 13 having no outstanding request is arranged after the last slot 12 assigned to the cold object.
  • MFS multi frequency scheduling
  • the MFS, EDF and RxW use a FCC (Full Cycle Completion) update system, and RxW is applied to ICR/R (Immediate Cycle Restart with object Reordering).
  • FCC Full Cycle Completion
  • ICR/R Immediate Cycle Restart with object Reordering
  • the FCC update system is a system that constructs a new carousel after all the data of the carousel constructed when starting the carousel are broadcasted, if a point of time when the carousel is started is different from a point of time when the objects included in a current carousel are determined.
  • the ICR/R is to schedule data of an entire carousel at carousel starting time, and, if a scheduling calculated at an intermediate update time is different from a scheduling of a carousel which is being currently broadcasted, suspend the current carousel and broadcast a newly calculated carousel.
  • objects to be included in the new carousel are determined by computing the modified RxW and taking objects having large values.
  • RxW is the product of the number of requests, which was early measured, and the waiting time Wi of an outstanding request for an object i, which is waited for the longest time.
  • Figs. 3(a) to 3(d) and 4(a) to 4(d) are graphical views showing success probability and response times, respectively, for a scheduling method depending on variations of the average number of received requests per second and the total number of data objects when skew values are varied.
  • the MFS of the present invention generally shows success probability higher than other scheduling methods, and the EDF applied to the FCC shows performance similar to the RxW applied to the FCC.
  • the MFS method shows response times shorter than the FCC (EDF), the FCC (RxW) and the ICR/R methods.
  • Figs. 5(a) and 5(b) are graphical views showing response time and success probability, respectively, depending on the average number of received requests per second and the total number of data objects when an upper limit value U of the number of times of hot object broadcastings is changed.
  • Figs. 6(a) and 6(b) are graphical views showing response time and success probability, respectively, depending on a scheduling method when the maximum waiting time P of a client is changed.
  • the graphs shown in these figures are graphs showing performances compared when the maximum waiting time P of a client is varied if the total number N of data objects is 50, the average number ⁇ of received requests per second is 2, and a skew value is 1.0. It can be seen from these graphs that the performance of MFS shows smoothly varying curves when P is varied from 20 to 60. In other words, as P increases, the response time and the success probability have a tendency to increase.
  • the MFS shows smooth variation while other methods show rapid variation, particularly, the FCC (EDF) is most sensitive to the variation of P.
  • the above-described method of the present invention may be embodied by a program which may be stored in a computer readable recording medium (for example, a CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.), details of which can be easily practiced by those skilled in the art and is therefore herein omitted.
  • a computer readable recording medium for example, a CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.

Abstract

L'invention concerne un procédé de programmation de diffusion numérique. En comparant un taux de demande avec un réciproque du nombre total d'objets de données en fonction des demandes reçues de clients et enregistrées dans un serveur, en classant les objets de données en des objets chauds et des objets froids, selon une considération préférentielle d'objets ayant une demande en attente qui attend sans avoir encore été diffusée, et en programmant un carrousel de sorte que les objets chauds et les objets froids sont agencés dans le carrousel selon le nombre de fois les objets chauds ont été diffusés et la priorité des objets froids, les objets de données peuvent être diffusés de manière régulière avec une probabilité de succès élevée et un temps de réponse court.
PCT/KR2007/001036 2007-02-28 2007-02-28 Procédé de programmation de service de diffusion numérique WO2008105568A1 (fr)

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Application Number Priority Date Filing Date Title
PCT/KR2007/001036 WO2008105568A1 (fr) 2007-02-28 2007-02-28 Procédé de programmation de service de diffusion numérique

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Application Number Priority Date Filing Date Title
PCT/KR2007/001036 WO2008105568A1 (fr) 2007-02-28 2007-02-28 Procédé de programmation de service de diffusion numérique

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104468143A (zh) * 2014-10-30 2015-03-25 武汉市武钢三中 一种广播环境下支持周期连续实时查询的广播调度算法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001035658A1 (fr) * 1999-11-08 2001-05-17 Gentor.Com Inc. Systeme de fourniture de services de portail radiodiffuses
US20020059599A1 (en) * 1995-10-02 2002-05-16 Starsight Telecast Incorporated Interactive computer system for providing television schedule information
US20030051252A1 (en) * 2000-04-14 2003-03-13 Kento Miyaoku Method, system, and apparatus for acquiring information concerning broadcast information
KR20060058946A (ko) * 2004-11-26 2006-06-01 삼성전자주식회사 데이터 방송 컨텐츠 전송 방법 및 장치, 데이터 방송컨텐츠 수신 방법 및 장치
KR20060114178A (ko) * 2005-04-29 2006-11-06 한국전자통신연구원 클라이언트의 요구를 반영한 방송 스케쥴링 방법

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020059599A1 (en) * 1995-10-02 2002-05-16 Starsight Telecast Incorporated Interactive computer system for providing television schedule information
WO2001035658A1 (fr) * 1999-11-08 2001-05-17 Gentor.Com Inc. Systeme de fourniture de services de portail radiodiffuses
US20030051252A1 (en) * 2000-04-14 2003-03-13 Kento Miyaoku Method, system, and apparatus for acquiring information concerning broadcast information
KR20060058946A (ko) * 2004-11-26 2006-06-01 삼성전자주식회사 데이터 방송 컨텐츠 전송 방법 및 장치, 데이터 방송컨텐츠 수신 방법 및 장치
KR20060114178A (ko) * 2005-04-29 2006-11-06 한국전자통신연구원 클라이언트의 요구를 반영한 방송 스케쥴링 방법

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104468143A (zh) * 2014-10-30 2015-03-25 武汉市武钢三中 一种广播环境下支持周期连续实时查询的广播调度算法
CN104468143B (zh) * 2014-10-30 2015-08-26 武汉市武钢三中 一种广播环境下支持周期连续实时查询的广播调度算法

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