WO2008062130A2

WO2008062130A2 - Method for modifying the set of streams received by a device in a network

Info

Publication number: WO2008062130A2
Application number: PCT/FR2007/052362
Authority: WO
Inventors: Christian Bertin
Original assignee: France Telecom
Priority date: 2006-11-20
Filing date: 2007-11-19
Publication date: 2008-05-29
Also published as: FR2908951A1; WO2008062130A3

Abstract

The method can be carried out by a device (10) connected to a telecommunications network (5) to modify the set of data streams (F1) received by said device (10). The method comprises the step of transmitting a unique command (200) to a node (20) in the network (5), which permits identification of the streams (F1) to be added to the set and those streams (F1) to be withdrawn from the set.

Description

Method for modifying all the streams received by a device on a network

Background of the invention

The invention lies in the field of telecommunication networks and, more specifically, in that of optimizing the reception of data streams in such networks.

The invention applies in particular, and in a nonlimiting manner, to the optimization of the reception of audiovisual streams broadcast in a network.

The International Engineering Task Force (I ETF) document RFC 3376, version 3, defines the I GMFV3 protocol (I nternet Group Management Protocol version 3). The I GMP protocol is the protocol used by the reception equipment in the Internet Protocol Version 4 (I FV4) systems to request or stop the reception of broadcast streams in multicast.

According to this protocol, the I FV4 systems use two separate commands, one to request the reception of a multicast stream and the other to request the termination of this reception.

The command to request the reception of a multicast stream is:

I PmulticastListen (socket, interface, multicast-address, filter-mode, source-list), with the following parameters: - socket: specific parameter used to distinguish the different entities at the origin of the I PMulticastLJsten command;

- interface: the local identifier of the network interface on which the reception of the specified broadcast address is to be allowed or deleted; - multicast-address: broadcast address I P targeted by the request; and

- filter-mode: predefined value FJ (CLUDE;

- source-list: is an unordered list that can contain 0, 1 or a plurality of addresses of the sources of the flows concerned by the request.

The command to request the stop of a reception is identical, the parameter filter-mode being equal to the predefined value I NCLUDE with the parameter "source-list" empty. The I GMR / 3 protocol is in particular used in Internet television applications for the reception of audiovisual channels.

It is thus understood that the change of channel, in other words the switching from a first channel to a second channel, requires the sending of a first command to request the stopping of the reception of the first channel, then the sending of a second command to request the reception of the second channel.

As a result, the waiting time of the display of the second channel is comparatively much longer than the usual channel change time for satellite, cable or terrestrial television reception.

OBJECT AND SUMMARY OF THE INVENTION Thus, and according to a first aspect, the invention relates to a method that can be implemented by a device connected to a telecommunications network to modify all the data streams received by this device via the network.

This method comprises a step of sending, to a node of the network, a single command to identify the flows to be added to the above set and the flows to be removed from this set.

Correlatively, the invention relates to a device that can be connected to a telecommunications network. This device comprises means for sending, to a node of the network, a single command for identifying the streams to be added to all the streams received by the device and the flows to be removed from this set.

The method and the device according to the invention thus make it possible, in an Internet television reception application, to considerably reduce the switching time from a first channel to a second channel, since the single command contains both the identifier of the first channel for which the reception must be stopped and the identifier of the second channel that the user wishes to receive.

In a particular embodiment of the invention, the single command comprises, for each stream to be added to all or removed from this set, an address of the stream broadcast source.

This command format has the advantage of being very close to that of the command I PMulticastListen of the protocol I GMFV3, so that the invention could easily be implemented in an extension of this protocol.

In a particular embodiment of the invention, the single command comprises an identifier a network interface of the device concerned by the modification. Thus, the single command according to the invention applies to the streams received by a given network interface of the device and not to all the interfaces of this device.

In a particular embodiment of the invention, the single command comprises an identifier of a process at the origin of the command.

Thus, the single command according to the invention applies to the flows concerned by a given process implemented by the device and not to all the processes running in this device.

In a particular embodiment of the invention, in which the device comprises a plurality of processes, the modification method comprises:

a step of receiving at least two requests, each of these requests being sent by one of the processes to request a modification of all the data streams received by this process; and

a step of generating the single command according to the content of these requests.

This particular embodiment advantageously makes it possible to manage conflicts for requests concerning the same interface. Thus, those skilled in the art will understand that the single command according to the invention must comprise, for a given interface, the union of the streams requested by all the processes concerned by this interface.

In a particular embodiment, the various steps of the modification method are determined by computer program instructions. Consequently, the invention also relates to a computer program on an information carrier, this program being capable of being implemented in a device according to the invention or more generally in a computer, this program comprising adapted instructions implementing the steps of a modification method as described above.

This program can use any programming language, and be in the form of source code, object code, or intermediate code between source code and object code, such as in a partially compiled form, or in any other form desirable shape.

The invention also relates to a computer-readable information medium, comprising instructions of a computer program as mentioned above. The information carrier may be any entity or device capable of storing the program. For example, the medium may comprise storage means, such as a ROM, for example a CD ROM or a microelectronic circuit ROM, or a magnetic recording medium, for example a floppy disk or a disk. hard.

On the other hand, the information medium may be a transmissible medium such as an electrical or optical signal, which may be conveyed via an electrical or optical cable, by radio or by other means. The program according to the invention can in particular be downloaded to a network of the Internet type.

Alternatively, the information carrier may be an integrated circuit in which the program is incorporated, the circuit being adapted to execute or to be used in the execution of the method in question.

Brief description of the drawings

Other features and advantages of the present invention will emerge from the description given below, with reference to the accompanying drawings which illustrate an embodiment having no limiting character. In the figures: - Figure 1 shows, in its environment, a device according to the invention in a particular embodiment;

FIG. 2 represents, in flowchart form, the main steps of a modification method according to the invention; and - Figure 3 shows an example of use of the invention.

Detailed description of an embodiment

Fig. 1 shows a device 10 according to the invention in its environment. It will be assumed in this example that the device 10 has the architecture of a conventional computer. This device comprises a processor 11, a RAM type RAM 12, a ROM type ROM 13.

In the embodiment described here, the read-only memory 13 comprises a computer program comprising instructions for carrying out the steps of the modification method according to the invention whose flowchart is shown in FIG. 2.

The RAM 12 includes variables necessary for the execution of this program. In the example described, the device 10 according to the invention is connected to the I nternet network 5.

For this purpose, it comprises communication means 14 constituted in this case by hardware and software capable of implementing the I nternet I P protocol. We will assume in the example described here that the device 10 according to the invention has two network interfaces referenced respectively IF ₁ and IF ₂ .

We will also assume that the device 10 according to the invention comprises two processes S ₁ and S ₂ adapted to receive data streams coming from the Internet network 5.

In FIG. 1, we have also represented a router 20 connected to the Internet network 5.

We will assume that this router 20 receives a set of television channels, this set bearing the general reference Z, from a not shown television channel distributor. We will assume that the device 10 according to the invention receives a set E ₁ of data stream, each of these streams corresponding in this example to a television channel, coming from the router 20.

When the device 10 according to the invention wishes to modify the flows it receives on this interface IF ₁ , it sends a single command 200 to the router 20.

This single command may comprise streams to be added to the set E ₁ and / or streams to be removed from the set E ₁ .

In FIG. 1, reference E _{2 is} the set thus modified of the flows received by the device 10 according to the invention on the interface IF ₁ .

We will now describe with reference to FIG 2 the main steps of a modification process implemented by the device 10 according to the invention.

We will assume that the device 10 according to the invention receives on its interface IF ₁ the set E ₁ of flows constituted by the television channels F ₁ , F ₃ and F ₈ .

We will assume that flows F ₁ and F ₃ are for process S ₁ and that stream F ₈ is for process S ₂ .

In the example described here, we will assume that the processor 1 1 of the device 10 receives, during a step E10, two requests R ₁ , Fi ₂ , respectively from the processes S ₁ and S ₂ .

We will suppose that, by the request R ₁ , the process S ₁ asks the processor 11:

stopping the reception of the stream F ₃ , continuing to receive the stream F ₁ , and

- to start receiving the stream F ₂ .

We will suppose that, by the request R ₂ , the process S ₂ asks the processor 11:

stopping the reception of the stream F ₈ , and starting the reception of the streams F ₃ and F ₇ .

This step E10 of receiving the two requests R ₁ , R ₂ is followed by a step E20 during which the processor 11 generates a single command 200 according to the content of the requests R ₁ and R ₂ .

To satisfy the two processes S ₁ and S ₂ , the flows that must be received on the interface IF ₁ are the streams F ₁ , F ₂ , F ₃ and F ₇ . As a result, the processor 11 generates a single command 200 in which it requests a modification of the streams F ₁ received by the device 10 on the interface IF ₁ , this modification being in this case constituted by: the addition of the streams F ₂ and F ₇ in the set of flows received on the interface IF ₁ ; and

the suppression of the flow F ₈ of this set. The step E20 of generation of the single command 200 is followed by a step E30 during which the processor 11 sends to the router 20, via the communication means 14, this single command 200.

Upon receipt of this single command 200, the router 20 selects the streams F ₁ , F ₂ , F ₃ and F ₇ in the set Z of the streams received from the television channel distributor, and sends these streams to the interface IF ₁ of the device 10 according to the invention.

On receiving these flows, the device 10 according to the invention sends the flows F ₁ and F ₂ to the process S ₁ and the flows F ₃ and F ₇ to the process S ₂ according to their requests R ₁ and Fi ₂ .

Referring to Fig. 3, we will now describe another application of the invention.

We will assume that the user of the device 10 according to the invention wishes to display, on a screen not referenced here, a full screen image and a small window embedded in this screen.

We will assume that the full screen image corresponds to a high-speed data stream F ₁ and that the small window inlaid corresponds to a low-speed data stream F ₂ .

Consequently, the device 10 according to the invention sends a single command 20O ₁ to the router 20 in which it asks to add, to all the flows received by the device 10 according to the invention, the flows F ₁ and F ₂ .

The set E ₁ of these streams is sent by the router 20 to the device 10 according to the invention.

We will now assume that the user wants to view in full screen the image that was embedded in the small window. This amounts to stopping the reception of the stream F ₁ , stopping the reception of the low-speed stream F ₂ and starting the reception of a stream F ₃ corresponding to the full-screen image contained in this small window.

The device 10 according to the invention therefore sends a single command 20O ₂ with all its parameters to the router 20.

Upon receipt of this single command 20O ₂ , the router 20 sends to the device 10 according to the invention, a set E ₂ of flow comprising only the flow F ₃ .

A variant of this application consists of successively displaying several low bit rate television channels in incrustation in the small window without stopping the broadband flow.

This amounts to stopping the stream F2, maintaining the stream F1 and requesting the reception of a stream F3.

Another application is to view a mosaic of windows for low-speed channels, some windows always have the same TV channel among a list of favorite channels and the other windows sucessively show the other channels by continuous scan.

Claims

REVENDI CATI ONS

1. A method that can be implemented by a device (10) connected to a telecommunications network (5) for modifying all the data streams (F ₁ ) received by said device (10) via said network (5), characterized in that it comprises a step of sending (E30), to a node (20) of said network (5), a single command (200) making it possible to identify the streams (F ₁ ) to be added to said together and the streams (F ₁ ) to be removed from said set.

2. A modification method according to claim 1, wherein said single command (200) comprises, for each of said streams (Fi) to be added to said set or removed from said set at least one broadcast source address (A) of said stream ( R).

3. A method of modification according to claim 1 or 2, characterized in that said single command (200) comprises an identifier (IdJ F ₁ ) of a network interface (IF ₁ ) of said device (10) concerned by said modification.

4. Modification method according to any one of claims 1 to 3, characterized in that said single command (200) comprises an identifier (Id-S ₁ ) of a process (S ₁ ) at the origin of said command (200).

5. Modification method according to claim 4, wherein said device comprises a plurality of processes (S ₁ , S ₂ ), characterized in that it comprises:

a step (E10) for receiving at least two requests (R ₁ , R ₂ ), each of said requests being transmitted by one of said processes (S ₁ ,

S ₂ ) to request a modification of all the data streams received by this process (S ₁ , S ₂ ); and

a step (E20) for generating said single command (200) according to the content of said requests (R ₁ , R ₂ ).

6. Device (10) connectable to a telecommunications network (5), characterized in that it comprises means for sending, to a node (20) of said network (5), a single command (200) for identifying flows (F ₁ ) to be added to all streams (F ₁ ) received by said device (10) and streams (Fj) to be removed from said set (200).

A computer program comprising instructions for performing the steps of the modification method according to any one of claims 1 to 5 when said program is executed by a computer.

Computer-readable recording medium (13) (10) on which is recorded a computer program comprising instructions for executing the steps of the modification method according to any one of claims 1 to 5.