EP1135893A1

EP1135893A1 - Protocol for remote launching of a software application and reserving network resources with quality of service

Info

Publication number: EP1135893A1
Application number: EP00966252A
Authority: EP
Inventors: Christian Wipliez; Stéphane STATIOTIS; Michel Bourbao; David Farcy
Original assignee: France Telecom SA
Current assignee: Orange SA
Priority date: 1999-10-04
Filing date: 2000-10-02
Publication date: 2001-09-26
Also published as: FR2799326B1; JP4993832B2; WO2001026301A1; CA2352988A1; FR2799326A1; JP2003511768A; US7079526B1; AU7670200A

Abstract

The invention concerns a protocol for remote launching of a software application and reserving network resources with quality of service between a caller terminal TA and a called terminal TB. Said protocol consists in: transmitting (A) from the caller terminal to the called terminal TB a reservation request for connection via a server and a transmission via an unconnected network and in establishing (B) between the caller terminal TA and the called terminal TB, a procedure for reserving network resources with quality of service by exchange of messages by transmission via the unconnected network. When the network resources reservation is accepted by the server, establishing (C), on the same physical network supporting the unconnected network via a control network RC, a connected network between the caller terminal and the called terminal. The connected network forms the network resource with quality of service for executing the remote software application between the caller terminal TA and the called terminal TB. The invention is applicable to a connected network, ATM network, and to an unconnected network, IP network.

Description

Protocol for launching a remote software application and reserving network resources with quality of service

With the advent of the exchange of information of all kinds, via the transmission networks, the problem of the configuration, the occupation and the rational use of these became of major importance. , in order to ensure transmission of this information under satisfactory conditions.

In general, the transmission of this information can be carried out, via these networks, in connected mode or in unconnected mode. During a transmission in connected mode, a calling entity cannot transmit information to a called entity without having previously asked the latter for permission to transmit blocks of information to it. The transmission process in connected mode therefore involves the implementation of a connection establishment, a succession of multiple connections, an exchange of information blocks and then the release of the connection. This is the case, for example, of communication by the switched telephone network, PSTN, or by the integrated digital network of ISDN services.

During a transmission in unconnected mode, the information is transmitted by routing to a distant entity which may be in an active or non-active state. In case of non-activity, the latter is replaced by a mailbox. For such a transmission mode, the characteristics of the data blocks transmitted must be known and with each transmission it is necessary to specify the control information which will be necessary so that these transmitted data, and the information conveyed by these, arrive at destination. In particular, the address of the distant, receiving entity and of the sending entity must be inserted in the transmitted data block for this purpose. This is particularly the case for the transmission of electronic mail, files and applications for which real-time communication is not necessary.

At present, the work published on the subject of programming, and configuration, of connected networks has mainly concerned programming and configuration processes with signaling. It will be recalled, in particular, that these signaling processes consist essentially of transporting the connection commands, also called signaling, via a signaling network called the signaling network.

More recently, the Universities of Kansas and Columbia (New York) in the United States of America have published work relating to the reservation of bandwidth in a transmission network using the GSMP resource reservation protocol, for Generic Swi tch Managemen t Protocol.

Among these works, we can cite the following articles: 1) "Realizing the MPEG-4 Mul timedia Delivery Framework", IEEE Network Magazine pp.35-45, November / December 1998. Special Issue on Transmission and Distribution of Digital Video, published by JF HUARD, AA LAZAR, KS LIM and GS TSELIKIS;

2) "A Programmabl e Transport Archi tect ure wi th QOS Guaran tee", IEEE Communications Magazine, Vol.36, No.10, pp. 54-62, October 1998 published by J.F. HUARD and A. A. LAZAR;

3) "The IEEE p. 1520 Standards Ini tia ti ve for Programmable Network Interfaces", IEEE Communications Magazine, Vol.36, No.10, pp. 64-70, October 1998, published by J. BIS AS, A.A. LAZAR, J.F. HUARD, K.S. LIM, S. MAHJOUB, L.F. PAU, M. SUZUKI, S. TORTENSSON, W.WANG and S. WEINSTEIN;

4) "Programming Telecommunication Networks", IEEE Network Magazine pp. 8-18, September / October 1997, published by A. A. LAZAR.

In addition, procedures for requesting the establishment of a connection across a network via a "web" browser have been the subject of work. Among these, we can cite: 5) the article entitled "Session Con trol for Broadband Mul timedia Servi ces usmg the HTTP Protocol", ATM Forum, February 1997, published by GOTA LEIJONHUFVUD Ericsson Telecom AB. Finally, the RMI (.Remote Method Invocation) and HTML (Hyper Text Marked Language) procedures are known in the JAVA environment for launching applications in a client-server architecture on an unconnected network.

The procedures mentioned above are satisfactory, but they must use the same network to ensure the transmission of information flows from the application. For example, it does not exist in aforementioned procedures of means to indicate towards the network used the value and the type of quality of service required. In addition, in the aforementioned procedures, there is a priori no coupling making it possible to ensure the launching of a connection of a connected network, nor a fortiori an application, the latter being distinct and independent of the unconnected network.

The object of the present invention is to remedy the drawbacks and limitations of the procedures of the prior art by implementing a protocol for launching a remote software application and reserving network resources with quality of service, a terminal the caller is thus able to launch a remote application on a called terminal when these terminals are connected on a connected network.

Another object of the present invention is also the implementation of a protocol for launching a remote software application and reserving network resources with quality of service in which, prior to the effective launch of the application, the calling terminal has made, by reservation, connections from an unconnected network.

Another object of the present invention is also, after completion of the connection by the network connected between the calling terminal and the called terminal, the implementation of a protocol allowing the implementation of a communication with a quality flow guaranteed service on the connected network.

Another object of the present invention is finally the implementation of a protocol for launching a remote software application and for booking network resources with quality of service more particularly intended for the management of videophone communications from the same set integrated at the level of the calling terminal. The protocol for launching a remote software application and reserving network resources with quality of service between a calling terminal and a called terminal, object of the present invention, is remarkable in that it consists in transmitting, from the calling terminal to the called terminal, a connection reservation request, via a server and an unconnected network transmission and to establish, between the calling terminal and the called terminal, a resource reservation process network with quality of service, by exchange of messages via transmission by the network not connected. Upon acceptance of the reservation of network resources by the server, a network connected between the calling terminal and the called terminal is established on the same physical network supporting the unconnected network, via a control network. The connected network constitutes the network resource with quality of service for executing the software application remotely between the calling terminal and the called terminal.

The protocol object of the present invention is intended for the remote implementation of software applications of any type with reservation of quality of service, but it is more particularly intended for videoconference applications for which the management bandwidth occupancy of connected networks by ensuring execution is essential.

The protocol which is the subject of the present invention will now be explained in the description below in conjunction with the figures, making it easier to understand in which: the figure represents it, in the form of a functional flowchart, the steps for implementing the protocol object of the present invention; - Figure lb shows a particular preferred embodiment of the protocol object of the present invention in the case where the unconnected network is the IP network, for Internet Protocol, and where the connected network is the ATM network; - The figure shows it by way of illustration the relative architecture of the connected and unconnected networks in the embodiment of Figure lb; FIG. 2 represents, by way of illustrative example, a detail of implementation of the protocol object of the present invention, in a preferred embodiment in which the connection reservation request and reservation process messages are established in JAVA environment;

- Figures 3a and 3b show screen pages displayed by the monitor of the calling terminal respectively of the called terminal in the case of a videoconference application.

The protocol for launching a remote software application and reserving network resources with quality of service, the subject of this document invention, will now be described in conjunction with Figure la and the following figures.

In general, it is indicated that the protocol object of the present invention is intended to be implemented between a calling terminal, denoted TA, and a called terminal, denoted TB. Of course, the calling terminal and the called terminal are equipped with the resources necessary to exchange information messages in the form of files and preferably in the form of screen pages allowing the establishment of an interactive dialogue between the calling terminal TA and the terminal called TB.

Referring to FIG. 1 a, it is indicated that, following a start step in which the terminal calling TA and the terminal called TB are necessarily physically interconnected to a network capable of putting the latter into communication, the terminal called TB being functionally independent of the calling terminal TA, the protocol object of the present invention consists, in step A, in transmitting from the calling terminal TA to the terminal called TB a connection reservation request, this request being denoted R _RC and being transmitted by via an S server and transmission via an unconnected network. Due to the transmission of this request via an unconnected network, this transmission implies the transmission conditions previously mentioned in the description, relating to the transmission of data or information messages on the unconnected network. Following step A above, the object of the present invention protocol, in step B, to establish between the calling terminal TA and the terminal called TB, a process of reserving network resources with quality of service. In general, it is indicated that this reservation process allows the user of the terminal TA to define certain parameters relating to network resources with quality of service, as will be described later in the description.

In accordance with a remarkable aspect of the protocol which is the subject of the present invention, it is indicated that the reservation process is established by exchange of messages via the server and the transmission by unconnected network previously mentioned with respect to step A.

Upon acceptance of the reservation of network resources by the server, the aforementioned called terminal or the user of the latter being capable of accepting the execution of the application, the protocol object of the present invention consists, in step C , preferably, on the same physical network supporting the unconnected network, via a control network RC, a network connected between the calling terminal TA and the terminal called TB. It will thus be recalled that, when the connected network is established, the transmission of information messages between the calling terminal TA and the called terminal TB satisfies the conditions previously mentioned in the description relating to the transmission of information messages on a connected network .

Thus, the connected network constitutes the network resource with quality of service allowing to execute the remote software application between the calling terminal and the called terminal.

In general, it is indicated that to carry out the implementation of the protocol which is the subject of the present invention, it is necessary that the connected network intended to transport the information flows with quality of service be controlled externally, the notion external control system covering both the implementation of a control network, the RC network, making it possible to configure the successive connections of the connected network or, where appropriate, of a translation system between the messages transmitted by the network not connected in order to reserve resources and existing signaling as defined previously in the description.

Different specific embodiments will now be described in conjunction with FIGS. 1b and 1c, which aim to define a preferred architecture of connected network systems, respectively of unconnected networks implemented to ensure the conduct of the protocol for launching an application. remote software and network resource reservation with quality of service in accordance with the object of the present invention. In general, with reference to FIG. 1b, it is indicated that the steps consisting in transmitting the connection reservation request R _rc and establishing between the calling terminal and the called terminal a network resource reservation process with quality of service are preferably performed from the server. Likewise, with reference to FIG. 1 a, it is indicated that, in a particularly advantageous manner, the server can be constituted by a "web" server. Under these conditions, the steps consisting in transmitting the connection reservation request and in establishing between the calling terminal TA and the terminal called TB a process of reserving network resources with quality of service can then consist of sending HTML messages, for Hyper Text Marked Language. With reference to FIGS. 1b and 1c, it is indicated that in this preferred embodiment, the protocol object of the present invention makes it possible to control links of an ATM network from an IP network, the ATM network constituting the connected network and the IP network the network not connected.

As shown in FIG. 1b, it is indicated that terminals, terminal calling TA and terminal called TB, of course have an IP type network interconnection card and an ATM type network interconnection card, in order to transport the quality of service information flows or, if necessary, to have the two protocol stacks on the same ATM interconnection card as shown in FIG. 1b. In this case, the two networks, IP network not connected and ATM network connected, are constituted on the same physical medium. In particular, IP applications, that is to say HTML messages or the like, are transported on an emulation of a local area network LAN, for Local Area Network, and ATM messages can be transmitted into the machine directly or after the AAL adaptation layer.

Thus, with reference to FIG. 1b, it is indicated that the two protocol stacks are supported by the same physical medium.

With reference to FIG. 1 a, when the connection to a server, such as in particular a "web" server, is established from the calling terminal TA, the dialogue can be established between the aforementioned calling terminal and the server by the intermediary of the HTTP protocol of a "web" browser for transferring messages and, where appropriate, programs, execution subprograms as will be described later in the description. Then, the server can then launch connection orders, as shown in FIG. 1 a, the connection orders being launched to a control network by means of an IP CORBA protocol, the control network comprising a CORBA BUS. to stations generating ATM links. It is indicated that, in a nonlimiting manner, with reference to FIG. 1 a, the configuration of the ATM network is carried out from a distributed programming platform, any other solution such as signaling by a third party agent can also be envisaged. . With reference to FIG. 1 a, it is indicated that, to make the connections on the ATM network, that is to say to configure the connected network as shown in the above-mentioned figure, the protocol used between the previously mentioned control network RC and the ATM network, constituting in fact the application transport network with quality of service, can be realized via a GSMP protocol, for Generic Swi tch Management Protocol.

It is thus understood that at the level of the connected network constituting the aforementioned transport network, this network can be made up of different subnets, subnetwork 1, subnetwork 2, without limitation, the ATM links between calling terminal TA and terminal called TB of course allowing the interconnection of the latter at any location. A more detailed description of a specific example of implementation of the protocol object of the present invention, in the case where the unconnected network is an IP network and where the server is a "web" server for example, will now be given in link with figure 2.

As shown in the aforementioned figure, the steps consisting in transmitting the connection reservation request and in establishing the process of reserving network resources with quality of service, that is to say the steps represented in FIG. 1a at points A , B, can consist at least in transmitting 1) from the calling terminal TA to the "web" server a connection request and, on connection of the calling terminal TA to the aforementioned server, in supplying 2) to the calling terminal TA an entry page. The provision of an entry page to the calling terminal TA is not described in detail in FIG. 2, because such an operation is a conventional operation, when accessing a terminal from a server, according to the transmission protocol by IP network. Following the supply of the entry page, the protocol object of the present invention consists of a step 3) in which the calling terminal downloads in the constituent memories of the latter from the server, and in particular from the "web" server, a subroutine for selecting quality of service parameters. Thus, the calling terminal, from this subroutine, will be able, through the guidance of the user of this calling terminal, to select the parameters for transmitting information relating to the application to be executed. The aforementioned step 3) is then followed by a step

3a) represented by a closed-loop arrow at the level of the calling terminal TA consisting in establishing, from the aforementioned calling terminal and the selection subroutine, a choice of quality of service parameters. Steps 3) and 3a) previously mentioned are then followed by step 4) consisting, after entering the desired communication and quality of service parameters, to transmit from the calling terminal TA to the server, "web" server, the choice of quality of service parameters selected.

Following step 4), it is then possible to establish, on the basis of the chosen quality of service parameters, the reservation of the connected network resources constituting the network resources with quality of service previously mentioned in the description. The reservation of the aforementioned resources is established from the server, "web" server, to the ATM network described above in connection with FIGS. 1b and 1a via the control network RC. Thus, at the end of step 4), the control network RC establishes a reservation of resources on the ATM network between the terminal calling TA and the terminal called TB.

Following the establishment of the reservation of the network resources connected, the protocol object of the present invention can advantageously consist in transmitting, in a step 5a), from the calling terminal TA to the terminal called TB, an execution request application, this application execution request comprising at least one identification code of the calling terminal TA. It will of course be understood that the step of transmitting the application execution request can then be carried out on the unconnected network although the reservation of the connected network resources has actually been carried out and the connected network has thus been established. In general, it is indicated that the application execution request comprises at least one identification code of the calling terminal TA. Following step 5a) above, the object of the present invention protocol, in step 5b), to establish at the terminal called TB a process for managing the application execution request. In FIG. 2, for this reason, the management process carried out in step 5b) is represented by a closed loop at the level of the terminal TB. In a particular preferred nonlimiting embodiment, the management process represented in step 5b) can advantageously include, on refusal by the terminal called TB of the application execution request, a step of transmission by the intermediary of the circuit not connected to the calling terminal TA of a request rejection message executing the application and encouraging the calling terminal TA to release the connection reservation. In FIG. 2, it is indicated that the step of transmitting the rejection message of the execution request is referenced 5c).

On the contrary, upon acceptance by the terminal called TB of the execution request, a step of transmission via the circuit not connected to the calling terminal of a message of acceptance of the application execution request and of launch of this application is carried out. In FIG. 2, the aforementioned step of transmitting a message for acceptance of the application execution request is denoted 5d).

On the contrary, in the absence of response from the terminal called TB for a predetermined period, absence of response to the application execution request, the protocol object of the present invention consists in carrying out the transmission, in a step 5e), following the aforementioned predetermined duration via the circuit connected to the calling terminal TA of a message of absence from the terminal called TB. In general, it is indicated that in FIG. 2, steps 5c), 5d) and 5e) are generally designated by response from Visio, visio generically designating an application dedicated to videoconferencing as will be described later in the description.

The protocol for launching a remote software application and reserving network resources with quality of service, which is the subject of the present invention, can be implemented, with regard to the connection reservation request and the subroutine selection of quality of service parameters, by means of subroutines, commonly known as applets or applets in JAVA environment.

Under these conditions, it is indicated that the step of downloading to the calling terminal from the server a subroutine for selecting quality of service parameters, can advantageously consist of loading a JAVA applet.

Finally, at the end of the execution of the application, that is to say at the end of the transmission of information messages by the ATM network, the calling terminal TA and the called terminal TB terminate their application locally in a similar way to the termination of a conventional telephone call for example or a communication on the ISDN network.

Following the termination of this communication, the calling terminal TA, which has established the connection, is then encouraged to perform a disconnection operation making it possible in fact to free up in step 7) the resources from the aforementioned "web" server of the network. ATM. The management of the assembly is therefore complete, the ATM network then being completely freed up and ready for a new reconfiguration later.

A more detailed description of specific elements of the protocol, object of the present invention, when the application is dedicated to a videoconference application, will now be given in conjunction with FIGS. 3a and 3b.

In such a situation, it is understood that the video information relating to the videoconference is transmitted by the ATM network and that for this purpose, the sub- Quality of service parameter selection program consisting of a JAVA applet allows the choice of subscriber, bandwidth and multicast parameters for Multicast. Regarding the implementation and transmission of JAVA applets, we will prefer the RMI mechanism, for Remote Method Invocation, created by the company JAVASOFT, due to the inadequacy of the RPC protocol, for .Remote Procedure Code, distributed object systems. The purpose of this RMI mechanism is: - to support remote invocation of JAVA objects; integrate the distributed object model in the JAVA environment in a natural way while keeping the object semantics of the language; to make the development of distributed applications simple; to preserve the security and safety provided by the aforementioned JAVA environment.

It is indicated that the aforementioned RMI mechanism uses the client / server concepts valid for a call. The RMI mechanism makes it possible to remotely invoke a JAVA object, which makes it possible to satisfy two of the three critical points mentioned above, namely: the dependence on the implementation of this mechanism, this RMI mechanism in fact using the 'IP address to find the remote RMI server; in addition, a videoconferencing service requires, at each terminal, terminal calling TA and terminal called TB, that the terminal called TB is powered up and connected and that an RMI server exists in the background on each of the aforementioned terminals. During a communication, the calling terminal

TA is both client and RMI server, and the terminal called TB is RMI server, even if the code is the same on each of the aforementioned terminals. Under these conditions, the videoconferencing service previously mentioned is therefore not completely independent of the terminal but it has the advantage of being secure because the only actions possible on each remote terminal are those defined in the server-side interface. In order to implement the above-mentioned videoconferencing service, it is however necessary to notify the terminal called TB of the application execution request previously mentioned in the description.

Within the framework of the implementation of the protocol, object of the present invention, in a JAVA environment, a satisfactory solution consists in introducing, at the level of the called terminal, a JAVA dialog box invoked remotely.

Under these conditions, the same numerical references corresponding to the steps for implementing the protocol object of the present invention as shown in FIG. 2 now dedicated to a videoconference application, the corresponding successive steps are given below: 1) the terminal calling TA connects to the "web" resource server;

2) an HTML page is provided by the latter to the terminal calling TA. The "web" server contains the information necessary for the service. It ensures the correspondence between the name and the IP address of the terminal calling TA similar to mailing lists; 3) the calling terminal TA downloads the JAVA applet, which makes it possible to choose the communication parameters such as subscriber B, bandwidth, multicast for multicast as mentioned previously, this list not being limiting. The aforementioned JAVA applet, as shown in FIG. 3a, comprises a screen page displayed at the level of the terminal calling TA and comprising at least two selection buttons, a "Connection" / "Disconnection" selection button as well as a adjustment of the required speed to ensure the transmission of videoconference data. The other parameters can be used for external control. The rate adjustment button is designated by "Kb Rate" in Figure 3a.

In a particularly advantageous manner, it is indicated that the "Connection" / "Disconnection" selection button is a button with reassignable function. According to a particularly advantageous aspect, the selection button "Connection" is allocated, following the reservation of network resources with quality of service, a synchronization function between the external control of the network and the launch of the videoconference application. Such an operating mode allows synchronization between the external network control and the actual launching of the videoconferencing application since it thus avoids launching the above-mentioned application before reserving the resources of the ATM network without which the application cannot of course work. 4) Pressing the "Connection" button in step 4) triggers the return to the "web" server of the connection establishment order. Under these conditions, the "web" server passes the reservation order to the control network RC and the latter establishes a reservation of ATM resources between the calling terminal TA and the terminal called TB by allocation of a virtual path VP, for Virtual Pa th, and a virtual channel VC, for Virtual Channel, per terminal after calculation of the routing operation. In the above example, the network management is distributed with reference to FIG. 1c using the CORBA protocol in order to obtain better efficiency when controlling the switches ensuring the connection to constitute the connected network.

5a) during the step considered, the JAVA applet previously mentioned further comprises a screen page displayed at the terminal called TB. This screen page comprising two buttons, an acceptance button, denoted "Accepted", and a refusal button for launching the application, button denoted "refused". The action carried out in the aforementioned step 5a) thus puts the calling terminal on hold with a message of the "Call in progress" type and in this way notifies the terminal called TB of a videoconference request via the box. dialog box, if necessary combined with a ringtone, this dialog box indicating the identity of the caller. Sure FIG. 3b, it is indicated that the word "Visio" designates the videoconferencing application in a generic manner, "Karnak" arbitrarily designates the identity of the calling terminal. The aforementioned dialog box as shown in FIG. 3b can advantageously be constituted by a JAVA application launched by means of the aforementioned RMI mechanism and thus allows the terminal called TB to respond to the terminal calling TA according to its decision. It is understood of course that under such conditions, the decision is made by the user of the terminal called TB.

The management of acceptance or refusal can then be carried out according to several choices using the two buttons previously mentioned in connection with FIG. 3b, acceptance or refusal buttons. The user of the called terminal can thus carry out the following actions: a) he can refuse the requested videoconference by pressing the "Denied" button, this action having the effect of then returning a code making it possible to indicate to the requester that his correspondent does not not want the videoconference and that the user of the calling terminal TA is in charge of releasing the resources previously reserved. This is the step

5c) of Figure 2. b) The called terminal can accept the requested videoconference by pressing the "Accepted" button, the corresponding return code being returned and the videoconference applications then being launched simultaneously on both terminals, calling terminal, called terminal, using the RMI mechanism. This is step 5d) of figure 2. c) The terminal called TB is connected, but it does not respond after the end of a timer module

"timer" whose duration can be set from 15 to 20 seconds for example. Under such conditions, the absence of the user of the called terminal TB is then indicated to the calling terminal TA. The aforementioned timer can advantageously be triggered at the terminal called TB when the JAVA dialog box is launched. This is step 5e) of Figure 2.

6) At the end of the communication, that is to say at the end of the videoconference application, the two subscribers using the terminals, terminal called TA and terminal called TB, terminate their application locally as on the telephone for example. The calling terminal which has established the connection must then terminate the connection by pressing the "Disconnect" button;

Pressing by the user at the level of the terminal calling TA on the "Disconnection" button, the function of which has not been reassigned then makes it possible to release the resources after the end of the videoconference and the end of the communication. The disconnection mechanism can then be similar to that of the connection but with the order to release the resources instead of reserving them.

Claims

1. Protocol for launching a remote software application and reserving network resources with quality of service, between a calling terminal and a called terminal, characterized in that it consists in: transmitting, from the calling terminal to the called terminal, a connection reservation request, via a server and an unconnected network transmission; - to establish, between the calling terminal and the called terminal, a network resource reservation process with quality of service, by exchange of messages via said transmission by unconnected network, and upon acceptance of said reservation of network resources by said server, to be established, on the same physical network supporting the unconnected network, via a control network, a network connected between said calling terminal and said called terminal, said connected network constituting said network resource with quality service to execute said software application remotely between said calling terminal and said called terminal.

2. Protocol according to claim 1, characterized in that said server being constituted by a server

"web", said steps consisting in transmitting the connection reservation request and in establishing between the calling terminal and the called terminal a process for reserving network resources with quality of service consists in sending HTML messages.

3. Protocol according to one of claims 1 or 2, characterized in that said steps consisting in transmitting the connection reservation request and in establishing said network resource reservation process with quality of service consists at least: in transmitting from said terminal calling said server a connection request; and, on connection of said terminal calling to said server, providing said calling terminal with an entry page; - to load into said calling terminal, from said server, a subroutine for selecting quality of service parameters; establishing, from said calling terminal and said selection subroutine, a choice of quality of service parameters; transmitting from said calling terminal to said server said choice of quality of service parameters; to establish, from the choice of the quality of service parameters, the reservation of the network resources connected, constituting the network resources with quality of service.

4. Protocol according to one of claims 1, 2 or 3, characterized in that, following the establishment of the reservation of the connected network resources, it also consists in: transmitting, from the calling terminal, to the called terminal, an application execution request, said application execution request comprising at least one identification code of the calling terminal; establishing, at said called terminal, a process for managing the application execution request.

5. Protocol according to claim 4, characterized in that said management process comprises: on refusal, by said called terminal, of the request for execution of the application, a transmission step, via said unconnected circuit , said calling terminal with a message rejecting said application execution request and encouraging the calling terminal to release said connection reservation; upon acceptance by said called terminal of the execution request, a step of transmission, via said unconnected circuit, to said calling terminal of a message of acceptance of said application execution request and launching of this application ; upon absence of response from said called terminal for a predetermined duration, transmission, following this determined duration via the unconnected circuit, to said calling terminal of an absence message from the called terminal.

6. Protocol according to one of claims 2 to 5, characterized in that the connection reservation request and the subroutine for selecting quality of service parameters consist of applets in JAVA environment.

7. Protocol according to claim 6, characterized in that, for a software application constituted by a videoconference session, transmitted by the network ATM, said quality of service parameter selection subroutine constituted by a JAVA applet allows the choice of subscriber, bandwidth and multicast parameters.

8. Protocol according to claim 7, characterized in that said JAVA applet comprises a screen page displayed at the level of the calling terminal comprising at least two selection buttons, a selection button "connection" / "disconnection" and a button for adjusting the transmission rate.

9. Protocol according to claim 8, characterized in that said selection button "connection" / "disconnection" is a button with reassignable function, the selection button "connection" being allocated, following the reservation of network resources with quality service, a synchronization function between the external network control and the launch of the videoconferencing application.

10. Protocol according to claim 8 or 9, characterized in that said JAVA applet further comprises a screen page displayed at said called terminal comprising two buttons, an acceptance button and a refusal button for launching the application.