Time delay compensation device for the management of multimedia communications via an asynchronous network and a telephone network

• US 20060193454A1
• Filed: 02/25/2004
• Published: 08/31/2006
• Est. Priority Date: 02/25/2003
• Status: Active Grant

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Abou-chakra, Rabih, Moulehiawy, Abdelkrim
• Granted Patent: US 7,483,523 B2
• Time in Patent Office: Days
• US Class Current: 379/90.01
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04M 7/0027 Collaboration services where a computer is used for data transfer and the telephone is used for telephonic communication
• CPC Class Codes: H04M 7/0051 where the data service is a multimedia messaging service
• CPC Class Codes: H04M 7/1205 where the types of switching equipement comprises PSTN/ISDN equipment and switching equipment of networks other than PSTN/ISDN, e.g. Internet Protocol networks

Abstract

A device is dedicated to managing multimedia communications via an asynchronous network (IPN) and a telephone network (TDMN) between firstly a first audio communications terminal (T1) with a first video communications terminal (PC1), and secondly a second audio communications terminal (T2) with a second video communications terminal (PC2). The device comprises management means (MG) serving to order link means (ML) to set up a telephone link (L1) between the audio communications terminals (T1, T2) via the traditional telephone network (TDMN) on receiving a request to set up a multimedia call between the first and second video communications terminals (PC1, PC2) via the asynchronous network (IPN).

Claims

1. A device for managing multimedia calls both via an asynchronous network (IPN) and via a traditional telephone network (TDMN) between firstly a first audio communications terminal (T1) associated with a first video communications terminal (PC1), and secondly a second audio communications terminal (T2) associated with a second video communications terminal (PC2);

these video communications terminals being suitable for requesting a multimedia call (L2-L3) capable of transmitting at least one video signal to be set up over the asynchronous network;

the device being characterized in that it comprises;

link means (ML) suitable for being ordered to set up a telephone link (L1) between said first and second audio communications terminals (T1, T2) via said traditional telephone network (TDMN); and

means (MAV1, MAV2) suitable for automatically supplying the link means (ML) with the identifiers of the first and second audio communications terminals (T1, T2) when a multimedia link (L2-L3) is to be set up between the first and second video communications terminals (PC1, PC2) via the asynchronous network (IPN).

2. A device according to claim 1, characterized in that said means (MAV1, MAV2) suitable for automatically supplying the identifiers of the first and second audio communications terminals (T1, T2) to the link means (ML) comprise, in each video communications terminal (PC1):

means (MAV1) for sending to the other video communications terminal (PC2) an identifier of the telephone terminal (Ti) associated with the video terminal in question (PCi);

means for receiving from the other video communications terminal (PC2) an identifier of the telephone terminal (T2) associated with said other video terminal (PC2); and

means for instructing the link means (ML) to set up a telephone link (L1) between the two terminals (T1, T2) as identified in this way.

3. A device according to claim 1, characterized in that said means suitable for automatically supplying the link means (ML) with the identifiers of the first and second audio communications terminals (T1, T2) comprise, in a node (B) of the traditional telephone network:

means for searching for the identifiers of the first and second audio communications terminals (T1, T2) in a centralized directory; and

means for instructing the link means (ML) to set up a telephone link (L1) between the two terminals (T1, T2) as identified in this way.

4. A device according to claim 1, characterized in that said management means (MG, MG′

) are arranged, on receiving a request to set up a multimedia call between said first and second video communications terminals (PC1, PC2);

i) to order said link means (ML) to set up a telephone link (L1) between said first and second audio communications terminals (T1, T2); and

ii) to apply to said audio data exchanged via said telephone link (L1) a transmission delay so as to compensate at least in part for a difference in transmission duration between said audio data via said telephone link (L1), and the video data exchanged between said first and second video communications terminal (PC1, PC2) via a multimedia link (L2) set up within said asynchronous network (IPN).

5. A device according to claim 4, characterized in that said management means (MG, MG′

) are arranged to apply to the audio data a transmission delay of predetermined duration.

6. A device according to claim 4, characterized in that said management means (MG, MG′

) are arranged to determine the duration of the delay to be applied to the audio data.

7. A device according to claim 6, characterized in that said management means (MG, MG′

) are arranged to determine said duration as a function of auxiliary data.

8. A device according to claim 7, characterized in that it includes management interface means (IG) suitable for delivering said auxiliary data.

9. A device according to claim 7, characterized in that said link means (ML) are arranged to establish so-called signaling links (L4-i) with said first and second video communications terminals (PC1, PC2) via said asynchronous network (IPN) in such a manner as to receive said auxiliary data sent by said first and second video communications terminal.

10. A device according to claim 9, characterized in that each video communications terminal (PCi) includes a microphone (MPi) suitable for picking up signals representative of audio data delivered by a user (Ui) of the audio communications terminal (Ti) with which it is paired, and said device includes auxiliary modules (MAi) each coupled to a microphone (MPi) within each of said first and second video communications terminals (PC1, PC2) and arranged to determine the difference in transmission duration of audio data over a multimedia link (L3) set up via the asynchronous network between said first and second video communications terminals (PC1, PC2) and over said telephone link (L1), and to generate auxiliary data representative of said difference.

11. A device according to claim 10, characterized in that each auxiliary module (MAi) comprises firstly processor means (PMi) arranged, on receiving said audio data:

i) to extract a portion therefrom;

ii) to constitute a primary packet with the audio data of said portion;

iii) to synchronize said primary packet with the exchanged video stream; and

iv) to transmit said primary packet to the auxiliary module (MAj) implanted in the video communications terminal (PCj) with which their own video communications terminal (PCi) has set up a multimedia link (L3) via said asynchronous network (IPN);

and secondly calculation means (CMi) arranged, on receiving a primary packet;

v) to apply a date and time stamp to said primary A device according to;

vi) to compare the audio data portion contained in said stamped primary packet to the stamped telephone audio data previously received via said audio communications terminal (Ti) and said microphone (MPi);

vii) when said portion is identical to some of said telephone audio data, to determine the difference in audio data transmission duration over the multimedia link set up via the asynchronous network (IPN) between said first and second video communications terminals (PC1, PC2) and over said telephone link (L1);

viii) to generate auxiliary data representative of said difference; and

ix) to transmit said auxiliary data to said link module (ML) via a signaling link (L4-i).

12. A device according to claim 11, characterized in that said processor means (PMi) are arranged, on receiving audio data and before transmitting said primary packet, to make up a secondary packet and to synchronize it with the exchanged audio stream, then to transmit said secondary packet to the calculation module (CMj) implanted in the video communications terminal (PCj) with which their own video communications terminal (PCi) has set up a multimedia link (L3) via said asynchronous network (IPN), and in that said calculation means (CMi) are arranged, on receiving a secondary packet, to order storage and date and time stamping of the telephone audio data coming from said audio communications terminal (Tj) via said microphone (MPi).

13. A device according to claim 9, characterized in that each video communications terminal (PCi) includes a microphone (MPi) suitable for picking up signals representative of audio data delivered by a loudspeaker (HPTj) of the audio communications terminal (Tj) with which it constitutes a pair, and said management means (MG′

) are arranged, after said telephone link (L1) has been set up, to transmit simultaneously to said first and second video communications terminals (PC1, PC2) via the telephone link (L1) their respective loudspeakers (HPTi) and microphones (mPi), a message (MES) defining an initial instant, and in that it includes auxiliary modules (MAi′

) each coupled to a microphone (MPi) within said first and second video communications terminals (PC1, PC2) and arranged to determine the transmission duration of video data over the multimedia link (L2) set up via the asynchronous network (IPN) between said first and second video communications terminals (PC1, PC2), and to generate auxiliary data representative of said duration.

14. A device according to claim 13, characterized in that each auxiliary module (MAi′

) comprises;

i) date and time stamping means (DMi) arranged firstly, on receiving said message (MES), to trigger a time counter, and to add a send time mark representative of the duration that has elapsed since said triggering of time counting to each video packet stream that is to be transmitted to the video communications terminal (PCj) with which their own video communications terminal (PCi) has set up a multimedia link (L2) via said asynchronous network (IPN), and secondly, on receiving a marked video packet stream, to add to said stream a receive time mark representative of the duration that has elapsed since said triggering of the time counter; and

ii) calculation means (CMi′

) arranged to respond to said send and receive time marks to determine the transmission duration of video data over the multimedia link (L2) set up via the asynchronous network (IPN) between said first and second video communications terminals (PC1, PC2), and then to generate auxiliary data representative of said transmission duration, and to transmit said auxiliary data to said link module (ML) via a signaling link (L4-i).

15. A device according to claim 14, characterized in that said management means (MG′

) are arranged to determine a real transmission duration of video data over the multimedia link (L2) set up via the asynchronous network (IPN) between said first and second video communications terminals (PC1, PC2) by adding the received transmission duration to the result of taking the difference between a first message transmission duration between said management means (MG) and the auxiliary module (MA2′

) implanted in the second video communications terminal (PC2) and a second message transmission duration between said management means (MG′

) and the auxiliary module (MA1′

) implanted in the first video communications terminal (PC1).

16. A device according to claim 15, characterized in that said management means (MG′

) are arranged to determine said first and second durations by an acoustic echo technique.

17. A video communications terminal (PC1) suitable for being connected to an asynchronous network (IPN) and to a traditional telephone network (TDMN), the terminal being characterized in that it includes a module (MAV1) for:

sending to another video communications terminal (PC2) an identifier of an audio communications terminal (T1) associated with the video terminal in question (PC1);

receiving from the other video communications terminal (PC2) an identifier of an audio communications terminal (T2) associated with said other video terminal (PC2); and

instructing link means (ML) of the traditional telephone network (TDMN) to set up a telephone link (L1) between said first and second audio communications terminals (T1, T2) via the traditional telephone network (TDMN) when a multimedia link (L2-L3) is to be set up between said video communications terminal (PC1) and another video communications terminal (PC2) via an asynchronous network (IPN).

18. A node (B, B′

) for a traditional telephone network, the node being characterized in that it includes means for;

receiving a signal indicating that a multimedia link (L2-L3) is to be set up between a video communications terminal (PC1) and another video communications terminal (PC2) via an asynchronous network (IPN);

then searching for the identifiers of first and second audio communications terminals (T1, T2) in a centralized directory, these two audio terminals being associated respectively with these two video communications terminals (PC1, PC2);

then instructing link means (ML) to set up a telephone link (L1) between the two audio communications terminals as identified in this way.