WO2015086975A1

WO2015086975A1 - Method for testing quality of service, and corresponding subscriber identity module, mobile terminal and system

Info

Publication number: WO2015086975A1
Application number: PCT/FR2014/053218
Authority: WO
Inventors: Tomasz Wozniak; Xavier BERTINI
Original assignee: Oberthur Technologies
Priority date: 2013-12-09
Filing date: 2014-12-08
Publication date: 2015-06-18
Also published as: FR3014630B1; FR3014630A1

Abstract

The invention concerns a method for testing the quality of service of a communication channel between a mobile terminal comprising a subscriber identity module for identifying a subscriber with respect to a mobile phone network operator, and a remote device of a target network. A data packet exchange protocol (PDP) context is activated in said mobile phone network for communication between the mobile terminal and the remote device. The method comprises the following steps, implemented by the subscriber identity module: sending, (322) via the communication channel implementing the PDP context, test data to said remote device, receiving (324), via the communication channel, a response to the sending of the test data, and processing (326) said response, in order to assess the quality of service of said communication channel.

Description

Quality of service test method, subscriber identity module, mobile terminal and corresponding system

FIELD OF THE INVENTION

The invention relates to the field of telecommunications. It relates in particular to a method of testing the quality of service of a communication channel between a mobile terminal and a remote device, by a subscriber identity module to a mobile telephone network, included in the terminal.

The invention also relates to a subscriber identity module, to a mobile terminal and to a corresponding system.

BACKGROUND OF THE INVENTION

In order to enable a mobile terminal, such as a mobile phone, to exchange data with a remote device of a target network, for example a server of a data network, a packet exchange protocol context data, PDP, is activated within a mobile network to which the terminal is hooked. Activation of this PDP context has the effect of opening a communication channel in the mobile network, for communication (a data exchange) with the target network, according to a data packet protocol.

To do this, the mobile terminal can send an activation request to a target node, noted SGSN (Serving GPRS Support Node in English), the mobile network, typically GPRS type (for General Packet Radio Service in English) . The sending of this request can be initiated by a request to open a communication channel to the target network, sent by a subscriber identity module to a mobile network (eg SIM card or U ICC or μβΙΜ ), for example incorporated in the mobile terminal. Activation of a PDP context can also be done at the initiative of the remote equipment, upon request of the latter to the SGSN node of the aforementioned mobile network.

The PDP context makes it possible, in particular, to make the mobile terminal visible by the target network hosting the remote device, by associating with the mobile terminal an address recognized by this target network, generally an IP address (for Internet Protocol in English), for example when the network target is an IP network, or X.121 in the case where the target network is X.25.

This target network may be external to the mobile network to which the mobile terminal is attached. This is for example the case of the Internet network. In some configurations, this target network may be a data subnet in the mobile network, for example managed by the operator of the mobile network.

The PDP context contains in particular quality of service (QoS) information. This information corresponds to the quality of service negotiated by the mobile terminal (or the remote device) when activating the PDP context, in order to establish a connection with the target network. The PDP context also generally includes routing information that has led, during its activation, for example to the selection of a gateway (GGSN for Gateway GPRS Support Node in English) to this target network, especially when it is external to the mobile phone network.

Whatever the target network to which the mobile terminal connects, the PDP context makes it possible to characterize this connection. A mobile terminal may also have activated several PDP contexts in parallel (just as a remote device may have activated several PDP context), typically to open several simultaneous sessions with different target networks or with quality levels. different service.

Thus, the PDP context indicates a logical association between the mobile terminal and nodes of the mobile network (SGSN and / or GGSN), thus defining a communication channel in the infrastructure of the mobile network to the target network. A PDP identifier is assigned to the context to identify the data (data packets) that are exchanged in this PDP context, and thus route them efficiently.

Then we are interested in the case where the activation of the PDP context occurs at the initiative of the mobile terminal.

Once the PDP context is activated, the mobile terminal informs the subscriber identity module of the opening of the communication channel to the target network.

However, activation of the PDP context does not guarantee the possibility of exchanging data successfully on the communication channel thus defined.

In addition, the activation of a PDP context with a requested quality of service does not guarantee that the quality of service actually available on the communication channel complies with the requested quality of service.

A mobile terminal may thus be required to test the quality of service of the communication channel thus opened.

However, it is difficult to transmit such quality of service information from the mobile terminal to the subscriber identity module respecting standard communication interfaces. For example, the commands defined in the ETSI TS 102.223 standard do not allow this information to be transmitted to the subscriber identity module.

The transmission of such quality of service information to the subscriber identity module therefore requires an adaptation of the terminal, for example an adaptation of the operating system installed on it.

In addition, this quality of service information obtained by the mobile terminal may be questionable because highly dependent on the mobile terminal used.

Or it may be interesting for the operator of the mobile network, to know reliably the quality of service of its network without depending on the type and software architecture of the connected mobile terminals. It should be noted that today, only NMR (Network Measurement Report) measurements are accessible by the subscriber identity module. The operator is therefore not informed of the quality of service of the open communication channel by activating a PDP context.

A solution for the operator to obtain information on the quality of service of his mobile network is to equip the latter with sensors located at many locations in the network. However, this solution is extremely expensive to deploy and maintain.

It is therefore necessary to find a solution enabling the operator to retrieve quality of service information on his mobile network at a lower cost, independently of the terminal and by maintaining the existing interfaces between the identity modules of the mobile phone. subscriber and the mobile terminals integrating them.

SUMMARY OF THE INVENTION

The present invention thus aims to overcome at least one of these disadvantages.

In this context, a first aspect of the invention relates to a method of testing the quality of service of a communication channel between a mobile terminal comprising a subscriber identity module with a mobile network operator, and a remote equipment of a target network, a data packet exchange protocol context, PDP, being activated in said mobile telephone network for communication between the mobile terminal and the remote equipment, the method being characterized in what it comprises the following steps, implemented by the subscriber identity module:

sending, via the communication channel implementing the PDP context, test data to said remote device,

receiving on the communication channel a response to the sending of the test data, and

processing said response, to evaluate the quality of service of said communication channel.

The invention thus enables a mobile telephone network operator to have access to the quality of service actually available on an open communication channel on his mobile telephone network between a mobile terminal and a remote device of a network. target, regardless of the mobile terminal.

Indeed, following the activation of a PDP data packet exchange protocol context in the mobile telephone network, a subscriber identity module with the operator located in the terminal performs a test of quality of service on the communication channel thus established.

To do this, test data is sent to the remote device via the channel and the response to that sending is analyzed by the subscriber identity module. The operator can thus retrieve quality of service data directly from the subscriber identity module, without having to modify the interface between the terminal and the subscriber identity module, or to adapt the terminal.

Finally, the operator can thus determine whether the quality of service of the connection is in accordance with the requested quality (negotiated) during the activation of the PDP context.

Other features of the method according to embodiments of the invention are described in the dependent claims.

According to the embodiments, the remote equipment may be infrastructure equipment such as for example a mobility management server (SGSN) of the mobile telephone network, or a piece of equipment of a data network subnetwork of the telephony network. mobile, or equipment of a data network external to the mobile network.

The PDP context can be activated on the initiative of the mobile terminal. Alternatively, the PDP context can be activated on the initiative of the remote equipment.

In embodiments of the invention, the method further comprises a step of modifying the communication channel between the mobile terminal and the remote equipment, for example, in the case of insufficiently evaluated quality of service.

Thus, when the quality of service does not conform to the quality of service negotiated during the activation of the PDP context, the communication channel can be modified (adapted).

In embodiments of the invention, the response processing step includes comparing at least one quality of service information evaluated based on the response of the remote device, with a predefined value of quality. of the activated PDP context, said modification of the communication channel being triggered by said subscriber identity module in case of a difference greater than a threshold value.

Thus, in these embodiments, the subscriber identity module itself makes the decision to modify the communication channel, depending on the test results, namely the response of the remote device to the test data.

In embodiments of the invention, the modification includes the activation by the terminal of another PDP context with another quality of service value.

For example, the activation of a new PDP context makes it possible to renegotiate the quality of service of the communication channel. The activation of this other context may in particular be triggered by an OPEN CHANNEL type command sent by the subscriber identity module to the mobile terminal.

In embodiments of the invention, the modification includes the change of mobile network by the subscriber identity module.

For example, in the case where the operator is not able to provide a satisfactory network quality in a geographical area for example, the subscriber identity module can advantageously connect to another network having for example a deal roaming with the operator of the initial telephony network. In embodiments of the invention, the subscriber identity module includes in memory an international IMSI subscriber identifier and another international subscriber identifier IMSI, and said modification comprises the toggle between the current IMSI identifier. and the other IMSI identifier.

Typically, the current IMSI identifier is specific to the initial network operator, while the other IMSI identifier corresponds for example to an intermediate operator (eg broker) having roaming agreements with other operators, for example foreigners.

These provisions (network change and IMSI flip-flop) ultimately lead to the activation of a new PDP context in order to obtain another quality of service.

In embodiments of the invention, the method also includes sending, by said subscriber identity module, to said remote equipment, quality of service data evaluated during the processing step by said module. subscriber identity.

Thus, in these modes, the remote equipment also receives data on the quality of service of the network, from the subscriber identity module.

This quality of service data can be raw data, i.e. quality of service parameter values such as throughput, response time, packet retransmission number, and so on.

This quality of service data can also be in the form of alerts, depending on the value of the quality of service parameters relative to the negotiated value of these parameters. For example, when the value of a parameter goes too far away from the negotiated value when the PDP context is activated, an alert can be generated by the subscriber identity module for this parameter, which then sends it to the remote equipment.

This quality of service data can also take the form of a global alert, evaluating the overall compliance of the parameters considered with the negotiated values.

In some cases, the remote device can also initiate a quality of service test by sending test data to the subscriber identity module, for example in push mode, and processing a response from the subscriber identity module. sending these data.

In embodiments of the invention, when certain conditions based on the quality of service data sent are fulfilled, the subscriber identity module receives a trigger command of said modification step from the remote equipment.

In embodiments of the invention, when certain conditions based on the quality of service data received by the remote equipment are fulfilled, the remote equipment disables the PDP context.

Thus, in these modes, the remote device itself makes the decision to modify the communication channel, and the subscriber identity module applies this decision by modifying the channel in response to a command from the remote device. The conditions to be fulfilled are, for example, relating to a critical number of alerts received, and / or to a critical number of parameters whose value does not conform to the value negotiated during the activation of the PDP context (with a value threshold).

Other conditions may be considered. These conditions can be set by the operator, the owner of the subscriber identity module or by the remote device, or otherwise.

In embodiments of the invention, the trigger command is received by another communication channel in the form of an SMS.

Thus, even when the PDP context is disabled or when the communication channel is inefficient (poor quality of service), the subscriber identity module can implement a modification step for the activation of a new context PDP with new settings.

In embodiments of the invention, the remote device is a mobile telephony network support server configured to validate the activation of the PDP context.

In embodiments of the invention, the method is periodically implemented or when certain particular events occur.

For example, the method is implemented to detect a predetermined event.

For example, the method is implemented when a new mobile network is detected near the mobile terminal, and / or when a new PDP context is activated, and / or at the request of a third party entity, thereby enabling regularly evaluate the quality of service of the mobile telecommunication network.

In embodiments of the invention, the quality of service is evaluated according to at least one of the following parameters: number of retransmission of at least one test data packet, response time to the sending of at least one test data packet, number of test data packets lost.

Thus, the quality of service is not only evaluated with respect to the signal strength (NMR).

In embodiments, the response to sending the test data includes at least one acknowledgment of the test data sent.

For example, the acknowledgment attests to the good reception of all the test data packets by the remote equipment.

Correlatively, a second aspect of the invention relates to a subscriber identity module with a mobile network operator, for a mobile terminal, a data packet exchange protocol context, PDP, being activated in said mobile telephone network for communication between the mobile terminal and a remote device, the subscriber identity module being characterized in that it comprises:

a module for sending, via the communication channel implementing the PDP context, test data to said remote device, a reception module on the communication channel, a response to the sending of the test data, and

a processing module of said response, for evaluating the quality of service of said communication channel.

Correlatively, a third aspect of the invention relates to a mobile terminal comprising a subscriber identity module as mentioned above.

Correlatively, a fourth aspect of the invention relates to a system comprising a mobile terminal with subscriber identity module as mentioned above, and a remote device.

The advantages, goals and special features of the subscriber identity module, the terminal and the system are similar to those of the aforementioned method.

In a particular embodiment, the various steps of the aforementioned method are determined by instructions of computer programs.

Accordingly, the invention also relates to a computer program on an information carrier, this program being capable of being implemented by a microprocessor, this program comprising instructions that when executed by the processor implement implement the steps of the method as mentioned 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 is also directed to a microprocessor-readable information medium, and including 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 microcircuit ROM, or a magnetic recording means, for example a hard disk, or a flash memory.

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 may in particular be downloaded to a storage platform of an Internet type network.

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.

The aforementioned information carrier and computer program have characteristics and advantages similar to the method they implement.

BRIEF DESCRIPTION OF THE FIGURES Other features and advantages of the invention will become apparent in the description below, illustrated by the accompanying figures which illustrate embodiments having no limiting character. In the figures:

- Figure 1 schematically illustrates a mobile network to which a mobile terminal connects, and connected to an external data packet network;

FIG. 2 illustrates an exemplary hardware architecture for a mobile terminal embodying a subscriber identity module according to a particular embodiment of the invention;

FIG. 3 illustrates message exchanges in the network of FIG. 1 during the implementation of a method of testing the quality of service of a communication channel according to one embodiment of the invention;

Figure 4 illustrates message exchanges in the network of Figure 1 in response to the QoS test of Figure 3. DETAILED DESCRIPTION OF THE INVENTION

The invention enables a client application of a subscriber identity module to a mobile network operator, for example incorporated in a mobile terminal, to test the quality of service of a communication channel established between the mobile terminal and a remote device of a target network, and this independently of the mobile terminal.

As described below, this quality of service test makes it possible, for example, to determine whether the quality of service of the connection complies with the quality requested when activating a PDP context enabling the terminal to exchange data with the remote equipment on the communication channel.

This PDP context can be activated on the initiative of the mobile terminal, the subscriber identity module, or the remote device.

In the following description, we are interested in the case where the subscriber identity module performs the quality of service test by sending test data to the remote equipment. However, in some cases, the remote device can also perform such a test with the subscriber identity module.

Then, based on responses to the quality of service test, the subscriber identity module can itself decide to act on the communication channel in order to improve the quality of service, especially when the quality of service does not improve. is not the one expected.

In other situations, information resulting from the quality of service test is transmitted to the remote device, which decides to act on the communication channel to modify it, if necessary. In particular, the remote device can act on this channel either directly or via the subscriber identity module by sending for example a command to modify the communication channel.

Figure 1 schematically illustrates a mobile telephone network 100 to which a mobile terminal 120 connects. The mobile telephone network 1 00 is for example a partially IP network, GPRS type, managed by a mobile operator. The application of the teachings of the invention as described later, to other types of mobile telephone network requires the transposition of the functions mentioned in connection with the GPRS into similar functions in these other types of wireless network, such as the Wi-Fi network when relying on an Interworking Wireless LAN architecture (l-WLAN) for example.

In this example, the mobile telephone network comprises a data subnet 102. This subnet 102 is typically an internal data packet network, for example specific to the operator of the mobile telephone network 100.

A device 103 may be connected to this subnet 102. For example, this equipment 103 is a server of the subnet 102.

The mobile telephone network 1 00 may also be connected to an external data packet network 140.

The external network 140 is for example a public IP network, like the Internet. As a variant, the external network 140 may be a private IP network allowing access to servers and services of this private network.

A remote device 150 may be connected to this external network 140. This remote device is for example a server, for example a service provider.

In practice, the mobile telephone network 1 00 comprises one or more servers SGSN 1 04 (for Serving GPRS Support Node in English), acting as packet routers and equipped with features dedicated to the management of the network 100.

On the one hand, this SGSN server 104 conducts the attaching procedures of the mobile terminals (e.g. the terminal 120) to the mobile telephone network 100, in particular using authentication and authorization procedures. This attachment procedure is known as the "attach request / response".

On the other hand, the SGSN server 104 receives requests for activation of a context PDP ("activation PDP context request") issued by equipment such as the mobile terminal 120, and leads these activations.

The PDP context can be activated on request from the mobile terminal 120 or at the initiative of a remote device (e.g. equipment 150 or 103) connected for example to a data network (e.g., external network 140, subnet 102).

In the following, for the sake of simplicity, consider the case where the PDP context activation request comes from the mobile terminal 120. The other case is within the reach of the person skilled in the art.

In practice, when a terminal wishes to exchange data with a remote device located in an external target network, the SGSN server conducts procedures for discovering and selecting the gateways of the mobile network to this target network, according to the parameters defined by the telecom operator of the network 100. Thus, in the example of FIG. 1, when the mobile terminal 120 wishes to exchange data with the equipment 150 of the external network 140, the SGSN server 104 requested by the activation of a PDP context, for example selects the gateway 106 which constitutes a gateway of the mobile network 100 to the external network 140.

When the target network is a subnet (e.g., subnet 102) of the mobile network 100, the SGSN server 104 also manages the routing of the data packets to the target network.

A mobile terminal 120 may have simultaneous connectivities with several gateways for exchanging data with equipment remote from several networks. For example, the mobile terminal may wish to exchange data with the equipment 103 of the subnet 102 and the equipment 150 of the external network 140. Several PDP contexts are then activated using the SGSN server 104.

Thus, in embodiments, the remote equipment is separate from the SGSN server 104, which server acts as a packet router between the mobile terminal 120 and the remote equipment 150 (or 103).

In other embodiments, the remote device is the SGSN server 104 itself.

In the remainder of the description, the case in which the target network is the external network 140 is described, and where the mobile terminal 120 wishes to exchange data with the remote equipment 150 of this external target network 140.

However, the invention is not limited to this case, and also covers the embodiments where the target network is a subnet 102 of the mobile telephone network 100, as well as the case where the target network is the telephony network. mobile 100 itself (and the remote equipment is the SGSN server 104 or another mobile terminal of the mobile network). It is, however, within the abilities of the person skilled in the art to apply the teachings relating to the case described in detail below, to the other cases of figures covered by the invention.

As shown in FIG. 1, the mobile terminal 120 comprises a subscriber identity module 122 with a mobile telephone operator operating the mobile telephone network 100.

The subscriber identity module 122 may for example correspond to a SIM card, USIM or U ICC (Universal Integrated Circuit Card) compliant with the ETSI TS 102 221 standard.

The subscriber identity module 122 may be implemented in an embedded or removable component of secure element type (eSE or SE) which is a chipset separate from the main processor of the mobile terminal.

The subscriber identity module 122 meets, for example, the ISO 781 6 specifications (ETSI TS 102 223 standard) or even the Common Criteria standard (ISO / IEC 15408). It can communicate with the mobile terminal 120 in which it is embedded or incorporated by means of APDU (Application Protocol Data Unit) frames. FIG. 2 represents an example of a possible architecture for a mobile terminal comprising a subscriber identity module, in accordance with embodiments of the invention.

This is for example the mobile terminal 120 shown in Figure 1, including a subscriber identity module 122.

The subscriber identity module 122 is adapted to implement the main steps of a method of testing the quality of service according to embodiments of the invention, as described later with reference to FIG. or 4.

The subscriber identity module 122 comprises a communication bus 20 to which are connected:

a processing unit 22 - or microprocessor - denoted CPU (for Central Processing Unit);

one or more non-volatile memories 24, for example ROM (for Read Only Memory), which can constitute a medium within the meaning of the invention, that is to say that can comprise a computer program comprising instructions for the implementation of a test method according to embodiments of the invention; this non-volatile memory can also be an EEPROM (for Electrically Erasable Read Only Memory) or a Flash memory;

a random access memory 26 or cache memory or volatile memory for example RAM (for Random Access Memory) comprising registers adapted to the recording of the variables and parameters created and modified during the execution of the aforementioned program; during the implementation of the invention. The instruction codes of the program stored in non-volatile memory (eg EEPROM or flash) are loaded into RAM memory for execution by the CPU processing unit;

- A communication interface 28 adapted to transmit and receive data, for example via a telecommunications network or a read / write interface. In particular, the terminal 120 includes a complementary communication interface (not shown) for interacting with the interface 28 for the purpose for example to transmit to the module 122 events or data from the mobile network or a user of the terminal.

The communication bus allows communication and interoperability between the different elements included in the subscriber identity module or connected to it. The representation of the bus is not limiting and, in particular, the processing unit is able to communicate instructions to any element of the subscriber identity module directly or via another element of this module. subscriber identity.

As will be described hereinafter with reference to FIG. 4, the implementation of a quality of service test according to embodiments of the invention can make it possible to modify the connection parameters of the mobile terminal. to a device remote from a target network based on the test results. In general, the subscriber identity module 122 includes in memory an international subscriber identifier IMSI associated with the operator of the mobile telephone network 100 (basic operator). It may also include one or more other IMSI identifiers, for example used by intermediate operators for authentication of the identity module 122 on international networks. Thus, after the quality of service test, the subscriber identity module 122 may for example switch from one IMSI to another.

Conventionally, the subscriber identity module 122 furthermore includes in memory a Forbidden Public Land Mobile Network (FPLMN) network file storing the so-called prohibited mobile telephone networks.

It is recalled that a mobile network is listed in this forbidden network file when an attempt to authenticate (or attach) the subscriber identity module 122 to this network has failed. Any future attempt to connect (or attach) to this network is prohibited as long as the network is listed in this network file.

Thus, at the end of the quality of service test, the current mobile telephone network 100 can be introduced into the FPLMN file of the subscriber identity module 122, so that the subscriber identity module 122 is forced to disconnect from the subscriber identity module 122. this network, for example to connect to another mobile network and activate a new PDP context.

Figure 3 shows steps of a method of testing the quality of service according to embodiments of the invention. Message exchanges are described between various entities in Figure 1.

In known manner, a prerequisite to any communication channel opening for exchanging data, is that the subscriber identity module 122 must be connected to a mobile telephone network.

In particular, the subscriber identity module 122 may have one of these three statuses of connectivity:

the "No Service" status means that the subscriber identity module 122 is not connected (i.e. has not authenticated) to any network,

- The "Limited Service" status means that the subscriber identity module 122 is not connected to a network, but that a network is nearby, this is for example the case of networks listed as networks prohibited in another elementary file denoted FPLMN,

the "Normal Service" status means that the subscriber identity module 122 is connected to a mobile telephone network.

Subsequently, it is assumed that the subscriber identity module 122 has a "Normal Service" status and is connected to the mobile telephone network 100. The mobile terminal 120 can therefore make telephone calls (eg voice calls) with other terminals. In the case where the subscriber identity module 122 is not connected to the mobile telephone network 100, a conventional connection procedure would be implemented.

Information on the mobile network to which the subscriber identity module 122 is connected is stored in one of the basic files of the subscriber identity module 122, generally called EF_LOCI (for Elementary File and LOCation Information).

The file includes a mobile network code (MNC), a network country code (MCC), and a location code (LAC) that identifies a set of cells of the mobile network that can be used for type communications. voice.

This EF_LOCI file is regularly refreshed, especially each time the network changes, and the subscriber identity module changes status.

The process of Figure 3 relates initially to the opening of a communication channel on the mobile telephone network 100 to exchange data.

To do this, as a first step, a client application (Applef) of the subscriber identity module 122 verifies that the mobile terminal 120 has the necessary capacities for this type of exchange, that is to say for exchanging information. data via a communication channel.

Subsequently, for the sake of simplicity, the steps implemented by the client application will be described with reference to the subscriber identity module.

Thus, during a step 300, the subscriber identity module 122 sends a PROVIDE LOCAL INFO command to the mobile terminal 120.

As described in the TS 102 223 standard in section 6.4.15, the PROVIDE LOCAL INFO command allows the subscriber identity module 122 to obtain information at the terminal (mobile terminal identity, local date and time, language of use, state of charge of the battery, accessible mobile telephony technology, for example GSM (for Global System for Mobile Communication) or UMTS (for Universal Mobile Telecommunications System), etc.

In response to this command, the mobile terminal 120 returns (step 302) to the subscriber identity module 122, a TERMINAL RESPONSE message. This message generally includes the information requested by the subscriber identity module 122. With the information in this message, the subscriber identity module 122 can ensure that the mobile terminal 120 has the necessary capabilities to support it. data exchange type communications.

It is subsequently assumed that the mobile terminal 120 is compatible with data exchange type communications.

During a step 304, the subscriber identity module 122 consults an elementary file EF_LOCIGPRS present in the memory of the subscriber identity module 122. This file includes routing information (RAI) for Routing Area Information for data communications over the GPRS network. In particular, in a similar way to the EF_LOCI file, the EF_LOCIGPRS file comprises a mobile network code (MNC), a network country code (MCC), and a location code (LAC) which identifies a set of cells of the network. mobile telephony that can be used for data communications (ie data exchange).

The consultation of this file makes it possible to collect the characteristics of the network to which the subscriber identity module is hooked and with which it will attempt to authenticate, in order to allow the exchange of data between the mobile terminal and here the remote equipment 150.

To do this, a context of exchange of PDP data packets (for Packet

Data Procotoi) will be activated in the mobile telephone network 100.

This activation can be done at the request of the remote device 150 from the SGSN server (via the GGSN gateway 106) or at the initiative of the mobile terminal 120. The latter case is described more fully below. However, the activation of a PDP context at the initiative of a remote device is well known to the person skilled in the art.

In this example, the subscriber identity module 122 initiates the establishment of a connection (i.e., the opening of a communication channel) to the target network 140, to which the remote device is connected. 150.

Thus, during a step 306, the subscriber identity module 122 requires the restoration of a connection (that is, the opening of a communication channel) to the external target network 140, with the mobile terminal 120 incorporating it. It is recalled that the subscriber identity module 122 is already connected to the mobile telephone network 100 for telephone communications, and that it is now necessary to establish another communication with the network, this time to exchange data. .

In practice, the subscriber identity module 122 provides the parameters necessary for the activation of a data packet service (PDP context), for example using an APDU frame (IS07816).

For example, the subscriber identity module 122 sends a BIP-compliant OPEN CHANN EL proactive command (defined in ETSI TS 102 223 v1 1) to require the mobile terminal 120, the activation of a PDP context on the mobile telephone network 1 00. The OPEN CHANNEL command includes a list of necessary parameters, sometimes called "Bearer Independent Protocol" parameters, for the activation of a PDP context, including the desired quality of service.

For example, this list may include a description ("bearer description"), the size of the buffer, the address of the target network, the port number of the module / terminal interface (eg UDP protocol, port P), the "Network Access Name" access point, which is the access point name (APN) for the GGSN gateway that provides the connection to the external target data network, the IP address of the remote device, etc. Thus, the desired quality of service (response time, speed, etc.) is transmitted via this OPEN CHANNEL command. Alternatively, the quality of service may be transmitted using any other proactive command sent by the subscriber identity module 122 to the mobile terminal 120.

On receipt of the request OPEN CHANN EL, the mobile terminal 120 triggers a procedure for attachment to the mobile telephone network 100, in order to open a communication channel for data exchanges.

In a conventional manner, this procedure comprises the sending (step 308) of an "Attach Request" request by the mobile terminal 120. This request is processed during a step 310 by the SGSN server 104 which retrieves subscription information. associated with the user with the network 100 and then performs authentication / authorization procedures based on this information, before accepting during a step 312, the attachment "Attach Accept". In a known manner, this attachment procedure involves an HLR server of the network 100.

Note that when connecting the subscriber identity module

122 to the telephony network 100 to enable the subscriber identity module 122 to implement conventional telephone communications (voice type), a similar attachment procedure has been implemented.

During a step 314, the mobile terminal 120 sends a new request "Activate PDP context Request" to the mobile telephone network 100 in order to activate a PDP context. This request includes parameters such as for example a quality of service value, an APN (Access Point Name), a type of PDP.

This request is processed in the course of step 316 in the conventional manner by the SGSN server 104 of the mobile telephone network 100. It is for this entity 104 to carry out the discovery and selection procedures as defined in the 3GPP standard. TS 29,303.

These discovery and selection procedures make it possible to select the target network (here the external network 140) targeted by the user, as well as the nodes internal to the mobile telephone network 100 making it possible to access the external target network 140, namely in particular the gateway 106.

In practice, the SGSN server 104 obtains a list of candidate internal nodes corresponding to the access to the desired target network. From this list, the appropriate node is selected, possibly based on several criteria, for example as a function of the network conditions such as the relative load between the various possible internal nodes, the geographical location of the entities of the network taking into account the nodes co -located, or the topological proximity of the nodes between them.

When the internal node (s) defining the PDP context are selected, the SGSN server 104 activates the PDP context for the mobile terminal 120, i.e. the communication channel between the mobile terminal 120 and the exit point 106 to the mobile terminal 120, i.e. the communication channel between the mobile terminal 120 and the exit point 106 to the mobile terminal 120. the desired target network. Concretely, the activation of the PDP context consists in assigning an identifier of context for marking the parquets of data to pass through this context PDP, and to associate with the mobile terminal 120 and all the entities for routing along the PDP context to the GGSN gateway.

To do this, the SGSN server sends, during a step 318, an "Activate PDP context Accept" acceptance to the mobile terminal 120. This acceptance includes, among other things, the quality of service negotiated with the SGSN server 104.

It should be noted that several PDP contexts can be activated by the SGSN server 104 for the same mobile terminal 120, which wishes to access several target networks simultaneously.

To separately identify each of the PDP contexts, a context identifier is assigned to them. This identifier is stored by the SGSN server 104, in association with an identifier of the mobile terminal 120. This information will indeed route response messages to the mobile terminal 120 ad hoc according to the context identifiers.

On receipt of the acceptance of the activation of the PDP context (step 318), the mobile terminal 120 responds during a step 320 to the command OPEN CHANN EL by a TERMINAL RESPONSE message to the identity module of Subscriber 122. If applicable, the same message type may be returned to indicate that the OPEN CHANNEL command was not executed successfully.

For example, the quality of service negotiated during the activation of the PDP context can be stored in a memory, for example the non-volatile memory 24, of the mobile terminal 120. The subscriber identity module 122 can access this memory , for example upon receipt of the TERM INAL RESPONSE message.

Alternatively, the negotiated quality of service can be transmitted to the subscriber identity module 122 as a parameter of the TERMINAL RESPONSE command in step 320.

As described below, the test method according to the invention aims in particular for the verification, by the subscriber identity module 122, of this negotiated quality of service.

As explained above, the invention is not limited to embodiments in which the PDP context is activated by the mobile terminal, and also covers the embodiments in which the remote device is at the initiative of the activation of the mobile terminal. PDP context.

According to the invention, the method then comprises sending (step 322) test data by the subscriber identity module 122 to the remote equipment 150, using the PDP context.

In practice, the test data is transmitted using the SEN D DATA function also described in the ETSI TS 102 223 standard, via the IS07816-compliant connection between the subscriber identity module 122 and the mobile terminal. 120, then transmitted via the previously activated PDP context, in the form of data packets, for example IP packets (IP transport protocol), or UDP packets (CAT-TP transport protocol).

The test data is, for example, any set of 40K of dummy data (the meaningless).

This data is split into data packets sent successively to the remote device via the PDP context.

Upon receipt of the test data packets, the equipment 150 returns a response (step 324) to the subscriber identity module 122.

The response preferably consists of one or more acknowledgments.

Thus, in some embodiments, the subscriber identity module 122 receives an acknowledgment for all of the test data, which testifies to the good reception of all the test data by the remote device.

In other embodiments, the subscriber identity module 122 receives a packet acknowledgment, or N acknowledgments if the test data is split into N packets and all are correctly received.

During a step 326, the response (consisting of one or more acknowledgments) of the equipment 150 is processed by the subscriber identity module 122.

In some embodiments, when no acknowledgment is received for one (or more) packet (s) after a certain duration by the subscriber identity module 122, the subscriber identity module 122 may re-transmit the data concerned (ie all test data, ie those constituting the packet or packets that have not been correctly transmitted to the equipment 150).

The processing step 326 may then include counting the retransmission number of each packet. This number constitutes information on the quality of service of the communication between the subscriber identity module r 122 and the remote device 150. An average of the retransmissions on all the packets can also constitute quality of service information.

In some modes, the processing step 326 includes calculating the elapsed time between the transmission of the data (step 322) and the receipt of the acknowledgment (step 324). This delay can be calculated for each packet, and / or averaged over all the packets.

In some embodiments, the number of reissues and / or the response delay may be compared to threshold values, or for example ranges of values surrounding the negotiated corresponding value (especially for the response time).

One or more parameters, such as the response time and the retransmission number, can thus be evaluated during the processing step 326.

Thus, at the end of the processing step 326, the subscriber identity module

122 knows the value of one or more parameters reflecting the quality of service available (e.g. number of retransmissions, average response time, speed ...).

In some modes, the subscriber identity module 122 compares these parameter values with predetermined values and therefore knows whether the quality parameters are or are not close to expected values (for example negotiated during the activation of the PDP context).

For example, the subscriber identity module 122 may generate one or more quality of service alerts, for each parameter concerned that does not have the expected value, or a general alert for all the quality of service parameters.

For example, a general alert can be generated when the number of parameters out of the expected ranges exceeds a certain threshold.

As a variant, a general alert can be generated as soon as one of the quality of service parameters considered is outside the expected range of values. For example, when the difference between the estimated flow and the negotiated flow exceeds the threshold value of 10%, an alert can be generated.

Response processing may include a combination of these modes. Some parameters may be compared to the expected values while others may not, so some parameters may be alerted while others may simply remain as 'raw' values.

Thus, the invention enables the subscriber identity module, and therefore the corresponding network operator, to estimate the actual quality of service of the communication channel between the mobile terminal 120 and the remote equipment 150, without as much to modify the communication interface (IS07816) between the subscriber identity module and the mobile terminal in which the module is inserted or embedded.

In addition, the operator can know this quality of service independently of the terminal in which the module is inserted, which may be advantageous especially in the case where the user changes mobile terminal while maintaining the same identity module subscriber.

Finally, thanks to the plurality of SIMs of its subscribers, the operator can now have a faithful evaluation of the quality of service of his network in many points, without cost of deployment.

In some cases, a quality of service test as described above at the level of the subscriber identity module, is carried out on the initiative of the remote equipment 150, for example in order to test the connection with a view to provision (eg spontaneous) of a service. The test data is sent by the remote equipment 150 to the subscriber identity module 122, and the equipment 150 then itself processes the response of the subscriber identity module 122.

These particular modes may be useful for determining whether the quality of service actually available between, for example, a service provider server, and the subscriber identity module, is sufficient to support services delivered for example in push mode, to the module of the service provider. subscriber identity.

Figure 4 shows steps of a method of testing the quality of service according to other embodiments of the invention. In particular, these embodiments comprise the steps 300 to 326 described with reference to FIG. 3, to which are added the steps described below with reference to FIG. 4, and which relate to actions taken to remedy a quality of insufficient service.

According to first embodiments, the result of the processing step 326 is sent by the subscriber identity module 122 to the remote equipment 150 in a step 328. As previously described, this result can include for example :

- one or more quality of service parameter values evaluated at step

326, and / or

- one or more alerts for quality of service parameters, and / or

- a general quality of service alert.

During a step 330, the remote equipment 150 processes this result. This processing 330 may comprise the counting of the number of alerts, and / or the comparison of the quality of service parameter values with the expected values (negotiated during the activation of the PDP context), and / or the counting of the parameters having a value that does not conform to the traded values.

When the remote equipment 150 determines that the quality of service is insufficient, it can command the closing of the PDP context, must directly by sending a command to the SGSN server 104 (step 332), or indirectly by sending a command to the identity module of subscriber 122 (step 334). In both cases, the command can be sent by the active communication channel, or by another means, for example by SMS.

In order to activate a new PDP context, the remote device may, for example, send an activation request to the SGSN server 104 (case not shown).

Alternatively, the equipment 150 may send a command to the subscriber identity module 122 (step 334) so that it requests the mobile terminal 120 to activate a new PDP context according to new parameters. These new parameters are for example included in the command from the equipment 122. Note that in the example of FIG. 1, the command for modifying the PDP context sent to the step 334 implicitly comprises a command to close the PDP context in progress, as mentioned above.

In practice, the command sent by the remote device 150 to the subscriber identity module 122 leads to the generation by it of a new command OPEN CHANNEL with new parameters (buffer size, quality of service, protocol of transport, mobile phone network, etc.) in order to activate a new PDP context according to these parameters.

On the other hand, the change of mobile network can be done via the switch of the current IMSI identifier to another IMSI identifier of the subscriber identity module. Typically, the current IMSI identifier is specific to the initial network operator, while the other IMSI identifier corresponds for example to an intermediate operator (eg broker) having roaming agreements with other operators, for example foreigners.

The change of mobile telephone network can thus be advantageous when the operator of the mobile telephone network 100 is not able to provide a satisfactory network quality at a given location.

It should be noted that when the subscriber identity module is embedded in the mobile terminal, the switch from one IMSI identifier to another occurs during the switch from one profile (also called business profile) to another.

It is recalled that a profile includes an IMSI identifier and a set of data and applications associated with the basic operator corresponding to this IMSI identifier.

In the case of switching from the current IMSI identifier to another IMSI identifier, a REFRESH command, for example sent by the remote device 150 allows the subscriber identity module to trigger new procedures (described above) resulting in when activating a new PDP context.

Alternatively, the network change (step 336) can be implemented by registering the mobile telephone network 100 in a forbidden network file FPLMN stored in the subscriber identity module, so as to prevent the reconnection to this network after refreshing the subscriber identity module parameter files 122, without changing the current IMSI identifier.

Thus, in known manner, the subscriber identity module will attempt to connect to the next mobile network near the terminal, as it appears in the list of preferred mobile networks linked to an IMSI.

According to the parameters targeted by the change command, the modification step 336 thus makes it possible to generate a new OPEN CHANNEL command including these parameters.

According to second embodiments of the invention, the result of the processing step 326 is not sent by the subscriber identity module 122 to the remote equipment 150 and the steps 328 to 334 do not have location.

In these second modes, the subscriber identity module 122 itself performs a comparison of the quality of service evaluated with threshold values to determine whether the quality of service is sufficient or not.

When the quality of service is insufficient, it makes itself the decision of the modifications to be made on the connection during the modification step 336, as described above.

For example, the subscriber identity module may change the connection parameters for a new OPEN CHANNEL command (step 338), or change the mobile network using an IMSI flip-flop ( or business profile), or using the FPLMN prohibited network file. As explained above, the change of the mobile telephone network may be advantageous for the operator in order to apparently ensure good network coverage, especially when the latter is not able to provide a quality of service. satisfactory service at a given location, but that another network managed by an operator with whom a roaming agreement has been passed offers a better quality of service.

The steps 322 and following described with reference to Figure 3 and / or 4, can be implemented when one of the following events is detected:

activation of a new PDP context, at the initiative of the terminal or the remote equipment,

- presence of a new mobile phone network near the mobile terminal,

- request from a third party entity (for example controlled by the operator of the mobile telephone network 100).

In a variant, the steps 322 and following described with reference to FIG. 3 and / or 4 may be implemented periodically.

The foregoing examples are only embodiments of the invention which is not limited thereto.

Claims

A method of testing the quality of service of a communication channel between a mobile terminal (120) comprising a subscriber identity module (122) with a mobile network operator, and a remote device ( 103; 104; 150) of a target network (100; 102; 140), a data packet exchange protocol context, PDP, being activated in said mobile network (100) for communication between the terminal mobile (120) and the remote equipment (103; 1 04; 1 50), the method being characterized in that it comprises the following steps, implemented by the subscriber identity module:

sending, (322) via the communication channel implementing the PDP context, test data to said remote device,

receiving (324), on the communication channel, a response to the sending of the test data, and

processing (326) said response to evaluate the quality of service of said communication channel.

2. Method according to claim 1, characterized in that it further comprises a step of modifying (336) the communication channel between the mobile terminal and the remote equipment.

The method of claim 2, characterized in that the processing step (326) includes comparing at least one quality of service information evaluated based on the response of the remote device, with a predetermined value. PDP context QoS enabled, said modification (336) of the communication channel being initiated by said subscriber identity module (122) if there is a difference greater than a threshold value.

4. Method according to any one of claims 2 to 3, characterized in that said modification comprises the activation (338) of another PDP context with another predetermined value of quality of service.

5. Method according to any one of claims 2 to 4, characterized in that said modification (336) comprises the change of mobile telephone network by the subscriber identity module.

6. Method according to any one of claims 2 to 5, characterized in that said subscriber identity module comprises in memory an international identifier current IMSI subscriber and another international subscriber identifier IMSI, and said modification (336) includes the toggle between the current IMSI identifier and the other IMSI identifier.

7. Method according to any one of claims 1 to 6, characterized in that the method also comprises sending (328), by said subscriber identity module, to said remote equipment, quality of service data evaluated during of the processing step by said subscriber identity module.

The method of claim 7, characterized in that when certain conditions based on the quality of service data sent are fulfilled, the subscriber identity module receives (334) a trigger command of said modification step from the remote equipment.

9. Method according to claim 8, characterized in that said triggering command is received by another communication channel in the form of an SMS.

10. Method according to any one of claims 7 to 9, characterized in that when certain conditions based on the quality of service data received by the remote equipment are fulfilled, the equipment causes the deactivation (332) of the PDP context. .

11. Method according to any one of claims 1 to 10, characterized in that the remote device is a support server (104) of the mobile network configured to validate the activation of the PDP context.

12. Method according to any one of claims 1 to 1 1, characterized in that the method is implemented periodically or when certain particular events occur.

13.Procédé according to any one of claims 1 to 12, characterized in that the quality of service is evaluated (326; 330) according to at least one of the following parameters: number of retransmission of at least one packet of test data, response time to send at least one test data packet, number of test data packets lost.

14.Procédé according to any one of claims 1 to 13, characterized in that said response to the sending of the test data comprises at least one acknowledgment of the test data sent.

15. Subscriber identity module (122) from a mobile network operator, for mobile terminal (120), a packet exchange protocol context data store, PDP, being activated in said mobile telephone network (100) for communication between the mobile terminal (120) and a remote device (1 03; 104; 150), the subscriber identity module being characterized in that that it comprises:

a module for sending, via the communication channel implementing the PDP context, test data to said remote device,

a reception module on the communication channel, a response to the sending of the test data, and

16. A mobile terminal (120) comprising a subscriber identity module (122) according to claim 15.

17.System comprising a mobile terminal (120) with subscriber identity module (122) according to claim 1 6, and a remote device.

18.A computer program comprising instructions for carrying out a method according to any one of claims 1 to 14, when loaded and executed by a microprocessor.

19. A microprocessor-readable information medium comprising the instructions of a computer program for carrying out a method according to any one of claims 1 to 14.