DE10119492B4 - Method for managing the mobility of telephone sets in a cordless telecommunications network - Google Patents

Abstract

A method of managing the mobility of a telephone set (6) associated with a cordless telecommunications network, said network employing in particular a central server (1), a mobility server (7) and a set of base units (2; 3) to which one or more telephone sets whereby each telephone set can pass from a connection to a first base unit (2) to a connection to a second base unit (3), the central server (1) and the base units (2; Followers communicate to perform the data-related communications on Internet connections, characterized in that it includes the following stages, which are:
- to record on the first base unit (2) a request to register a telephone set (230);
To transmit a request to notify the registration (233) from the first base unit (2) to the mobility server (7) connected to the central server (1);
To update a database (8) of the mobility server (7) ...

Description

The The invention relates to a method for managing the mobility of a Telephone set belonging to a cordless telecommunications network, after The preamble of claim 1. Such a method is out GB-2 349 780 A is known. It concerns a telecommunications network which a system of the type DECT (Digital European Cordless Telecommunication) which uses Internet type connections to intervene various elements of the network to transport voice information.

In In this particular context, the invention enables one User to make a location change with his telephone set by all services offered to a user who not moving away, available stay. Thanks to the invention, a user of a telephone set can in particular from one through a first base unit of the cordless telecommunications system covered zone to another zone, that of a second base unit of this telecommunication system is covered, wherein the characteristics of the network in question and good quality of call stay.

The Internet connections are communication tools that are increasingly used become. An internet connection allows two units of data exchange, provided these two units have one Address, which is determined by a communication protocol that communicates organized on this connection, can be interpreted. Such Addresses become IP addresses (Internet Protocol) called. To the transfer to ensure data related to the language on an internet connection and to provide various services with transportation the language are connected, have been different communication protocols set up.

One The first protocols that were developed was the protocol H323, which made it possible in particular a conversion problem between a phone number coming from a Unit is chosen at one of the ends of an Internet connection, and an IP address the unit that dialed is to be solved. For example, this sender type sends a sender terminal, which wishes to communicate with another receiving terminal from which knows only one phone number, to a central server of the Network to which the terminals belong, an application for communication, accompanied by the telephone number. The central server now interprets the telephone number using a database to the IP address of the receiving terminal to determine which corresponds to this telephone number. The central server is now able to contact the receiving terminal, and the Both terminal facilities can Get in touch to exchange data. This protocol type corresponds to an approximation of the protocols used in the digital Network with Service Integration (RNIS) can be used to to the internet connections to be able to adapt.

In As a result, further protocols have been developed. especially the Protocols MGCP and MEGACO (Media Gateway Control Protocol or MEdia GAteway COntrol in English) were developed, the display protocols represent to data transfers related to the language to perform internet connections. The significant differences between the MGCP protocol and the protocol MEGACO consist in the syntax of the applications.

at the protocol MGCP is the central server call broker (Call Agent), and the customer facilities become access points Called (Gateway or Media Gateway); at the protocol MEGACO becomes the Central Server Media Access Point Controller (Media Gateway Controller), and the customer facilities become media access points Called (Media Gateway). An access point in this type of network is called either a terminal assigned to a telephone set or a telephone set Connection between the Internet network and another telephone network, such as a GSM network, a DECT network or the conventional telephone network, which is either digital or analog.

These Protocols are executed as so-called master / followers: this means that the Customer end devices receive commands from a central server, especially about her the list of events to be noted informed. When a the terminal detects one of these events, it transmits one Message to the server to let them know that they have this Event has observed. The communication between the customer facilities of the network and the central server of the network is done by a Exchange of in binary form Data sent applications.

The list of events to be observed may be constituted by telephone pick-up event detection events, telephone number entry detection, dialing of a regular expression to determine when a telephone number is complete: the server may specify the customer in that a number is considered complete if, for example, it comprises 4 digits or if it begins with 00. Any intelligence of such a communication network managed by this type of protocol is thus in the server concentrated. The server sends all necessary messages to the customer to connect. For example, to make a call, about a dozen messages must be sent from the server to the customer. The customer facility is limited to sending notification messages to the central server containing the observation of certain events.

The Interest in such a system is that in order to offer additional services, only the server changed must become. The terminal is a passive element of the network. To the communication system enriching it, it is sufficient to increase the capacity or the services to diversify within the server.

The Access points that are addressed by these protocols can do two things Type: first are the so-called resident access points (Residential Gateway) to find. They are formed by a terminal, that possibly over has several communication lines, each of these lines ends with a single participant. The protocols define the Term of end point (end point); one endpoint corresponds to one Communication channel connected to the access point. For example, an access point that has four lines has four Endpoints. In this case, starting from the IP address of the Access point can be accessed on four endpoints. The address format, which makes it possible accessing these endpoints must be at the same time the IP address of the access point and the name of the endpoint. If an endpoint is addressed, inevitably becomes a user that is still on the same access point.

It There are also so-called non-resident access points (Trunking Gateway). In this case, one endpoint is a line out of the network. It so must a phone number dialed on the line must be around that interlocutor really reach.

Of the The subject of the patent has as a framework a telecommunications network, which Lines includes, on which the respective data exchange through the protocols MGCP or MEGACO is managed. The data transfers related to the language on internet connections are also possible.

The Invention essentially deals with the case where the endpoints Telephone sets of a DECT type system. The access points will be now from base units or DECT base units formed, which are connected to a company network or data network.

however the display protocols that enable voice signals Internet connections, such as those just described MGCP protocols and MEGACO protocols to transport see No procedure to increase the mobility of the telephone within to manage the network. So if the cordless telecommunications network DECT is used in which the data server to different Base units connected by internet connections and in which the protocols MGCP and MEGACO are used, and if a telephone set from a first geographical zone, that of a first base unit is covered, in a second geographical Zone changes, which is covered by a second base unit can the user of the telephone set no longer communicate on the network. This restricts the interest and the capacities of such a network strongly.

The GB-2 349 780 A describes a method for managing the mobility of a Telephone set belonging to a cordless telecommunications network. This Network has a central server, a mobility server and a whole from base units to, to one or more telephone sets are connected, each telephone by a connection to a first base unit to connect to a second base unit can, where the central server and the base units after a Protocol of type master / follower communicate to the data transfer in connection with the language to perform internet connections.

The US-A-5,912,878 relates to a method for managing the mobility of a Telephone apparatus belonging to a cordless telecommunications network, this one Network a central and mobility server and a set of base units to which one or several telephone sets are connected. Every telephone set can connect to from a connection to a first base unit go over a second base unit. The central server and the base units communicate after one Master / Follower protocol related to data transfer using the language to perform internet connections.

at the method according to the document LO, A., SEAH, W., SCHREUDER E .: "An Efficient DECT Mobile IP Interworking for Mobile Computing, In: Vehicular Technology Conference Proceedings VTC 2000 Tokyo, Vol.1, 15-18 May 2000, pages 274-278 becomes such a process with all necessary procedural steps in the form of messages sent between the individual network elements described.

The inventive method allows to solve the problem outlined above. For this purpose, the invention proposes an extension of the existing protocols before to over funds too feature, with the help of applications, between the data server and different base units of the Net circulation, mobility To manage telephones of the network. The extension of the protocols allows it, a stage of registration of telephone sets in communication systems, a stage in the question of the localization of this telephone set, a stage of localization and initialization of this telephone set new define. Furthermore, according to the invention, the requests that are between circulating and differentiating the various elements of the telecommunications network which make it possible the mobility to manage the telephones, on instructions already in These communication protocols are defined and used. The invention thus defines a new set of events for the Management of mobility of the telephone sets, in particular the direction of an instruction, which already exists in the relevant logs to a to flag, divert, and change another event.

• – auf der ersten Basiseinheit einen Antrag zur Registrierung eines Telefonapparates zu erfassen;
• – einen Antrag zur Mitteilung der Registrierung von der ersten Basiseinheit zu dem an den Zentralserver angeschlossenen Mobilitätsserver zu übertragen;
• – eine Datenbasis des Mobilitätsservers zu aktualisieren, indem in der Datenbasis eine Identifikationsinformation, die den Telefonapparat angibt, der den Registrierantrag entsandt hat, und eine Lokalisierinformation, die die zweite Basiseinheit angibt, verbunden werden;
• – auf der zweiten Basiseinheit einen Antrag zur Anforderung der Lokalisierung des Telefonapparats auf dieser zweiten Basis zu erfassen;
• – einen Antrag zur Übertragung des Geheimschlüssels zwischen dem Mobilitätsserver und der zweiten Basiseinheit im Hinblick auf eine Authentifizierung des Telefonapparats zu entsenden;
• – einen Antrag zur Bestätigung der Lokalisierung von der zweiten Basiseinheit zu dem Mobilitätsserver zu übertragen;
• – von dem Mobilitätsserver zu dem Zentralserver einen Antrag zu übertragen, der angibt, daß der Telefonapparat einen Antrag auf Bestätigung der Lokalisierung innerhalb des Fernmeldenetzes entsandt hat;
• – von dem Zentralserver zu der zweiten Basiseinheit eine Gesamtheit von Anträgen auf Reinitialisierung zu übertragen.

The invention thus relates to a method for managing the mobility of a telephone set belonging to a cordless telecommunications network, this network in particular employing a central server, a mobility server and a set of base units to which one or more telephone sets are connected, each telephone set being linked may transition to a first base unit for connection to a second base unit, the central server and the base units communicating according to a master / follower type protocol to perform the data-related communications on Internet connections, characterized in that it comprises includes the following stages, which consist in:

• - to record on the first base unit a request to register a telephone set;
• To transmit a request to notify the registration from the first base unit to the mobility server connected to the central server;
• To update a database of the mobility server by connecting in the database identification information indicating the telephone set that has sent the registration request and location information indicating the second base unit;
• To record on the second base unit a request for locating the telephone set on this second basis;
• To send a request for transmission of the secret key between the mobility server and the second base unit with regard to an authentication of the telephone set;
• To transmit a request for confirmation of location from the second base unit to the mobility server;
• To transmit from the mobility server to the central server an application indicating that the telephone set has sent a request for confirmation of the location within the telecommunications network;
• Transfer a set of requests for reinitialization from the central server to the second base unit.

In addition, the request for indication of localization will be sent in the form of an application for reinitialization. The process according to the invention can be used at will with the aid of the MGCP or the MEGACO protocol. Moreover, the method according to the invention proposes the use of a digital secret key associated with each identification information contained in the database of the mobility server. This digital secret key is used particularly at the stage of authentication of the telephone set. The various applications between the base units, the central server and the mobility server are transmitted through Internet connections. Moreover, the applications used when using the method according to the invention have a special syntax, but which relies on control commands that are already used in the MGCP and MEGACO protocols that control the communications, and thus not necessarily for the Use of the method according to the invention are specific. In certain embodiments, the mobility server may 7 and the central server 1 be replaced by a single server that fulfills all functions.

The Invention and its various applications are by trial the following description and the accompanying figures better understood. These have only indicative character and are for the invention by no means restrictive. The figures show:

1 a block diagram illustrating in a simplified manner a situation in which to manage the mobility of a telephone set;

2 a detailed representation of the various events that occur to manage the mobility of a telephone set within the telecommunications network, each event being associated with a request from or to the mobile server, a database or the central server.

In 1 allows a central server 1 in particular to manage a cordless telecommunications network of the type DECT, which in particular a first base unit 2 and a second base unit 3 starts. The first base unit 2 has a limited coverage area 4 , The second base unit 3 has a likewise limited coverage area 5 , In general, the coverage areas of such systems are defined such that their coverage is minimal and the total covered area is maximum. A mobility server 7 is to the different base units 2 and 3 on the one hand and to the central server 1 on the other hand connected. The connections between the mobility server, the central server and the various base units ensure data exchange controlled by the MGCP or MEGACO protocol. These connections can be Internet connections in particular.

A mobile telephone 6 belongs to a user of the telecommunications network. The telephone set 6 communicates with the base units 2 and 3 according to a protocol defined in the DECT system. The user in the company of his telephone 6 is able from the first coverage area 4 in the second covering zone 5 cross over. Without the use of the method according to the invention, it would no longer be possible via the telecommunications network to which the base units belong 2 and 3 mobility management is not originally provided for in the MGCP and MEGACO protocols.

According to the invention, the mobility server comprises 7 also a database 8th containing multiple fields. A first field A of the database 8th may include identification information enabling to designate a single telephone set among the totality of telephones of the telecommunication network. The identification information contained in the field A is associated in a field B with so-called authentication information, which is provided in the form of a digital secret key specific to the telephone set on the same line of the database 8th is defined. Location information associated with the authentication information and the identification information of a telephone set is stored in a field C. The location information makes it possible to determine the last base unit to which the telephone set in question was registered.

The database 8th the mobility server 7 may possibly contain other information: in particular, it can inform the telecommunications network by indicating to it whether a given telephone set is able to be connected by means of another telecommunications network, for example of the GSM type. In the case of a two-mode telephone set, ie which is able to be connected, for example via a DECT system or a GSM network, the central server 1 first try to connect a telephone set over the last base unit of the DECT network assigned to the telephone set. In the event of a failure, the central server can send information to the caller who wishes to contact the telephone set indicating that this telephone set can be connected from the GSM network.

In 2 are the various applications that exist between the central server 1 , the mobility server 7 and the base units 2 and 3 circulate, represented. timelines 20 . 21 and 22 are the central server 1 , the mobility server 7 or the basic units 2 and 3 allocated. These timelines make it possible to present in chronological order the various applications sent or received by the various elements of the telecommunications network, each request corresponding to one stage of the method according to the invention. The applications are represented symbolically by horizontal arrows that go from a first time axis to a second time axis.

In order to manage the mobility of the telephone sets in a telecommunication network employing a DECT type system, the management of the mobile telephone sets has to be centralized. In the invention, this centralization occurs within the mobility server 7 , In certain embodiments, however, it is possible for the mobility server to be in the central server 1 is integrated. In particular, among the various events to be observed, there is a stage of registering the telephone set: when a telephone set is added to the telecommunications network, its description must be delivered to the server responsible for the mobility. This can be done either by direct configuration of the mobility server 7 via a configuration interface of this server or through a message sent from an access point to the server. Now follows a stage of authentication of the telephone set: before a telephone set receives admission to communication on the network, its identity must be checked. Then the stage of localization of the telephone sets follows: it must be constantly known where the telephone sets are located, ie which access point must be used to interact with this telephone set.

In 2 There are three main phases: a phase of registration 23 a telephone set, a phase of localization 24 the telephone ap parats and a phase of initialization 25 of the telephone set.

The phase of registration 23 of a telephone set includes a first event 230 which consists within the first base unit 2 the telephone in the form of a reference 231 and a secret key 232 to register. For this purpose, the first base unit 2 in a state of registration, recording of a new telephone set, for example, by pressing a key of the base unit 2 or by sending a management message from the central server 1 brought. Then the telephone set to be registered is to search for an access point. The telephone now logs on to a detected access point from the first base unit 2 is formed, which now includes an application for registration of the telephone set. A proposal 233 will now go to the mobility server from the base unit where the registration took place 7 sent.

This application tells the mobility server 7 the registration of a new telephone set with; in particular, it comprises two parameters representing identification information of the registered telephone set accompanied by its digital secret key and the number of the base at which it was registered. This application is called for notification of registration.

The database 8th the mobility server 7 must now in a second event 234 the registration phase 23 to be updated. The various fields A, B and C are informed for this purpose. A proposal 235 who is updating the database 8th confirmed, is now from the mobility server 7 to the base unit 2 sent.

If the user of the telephone set 6 makes a change of location and, for example, from the first coverage area 4 in the second covering zone 5 - goes over, looks for the telephone set 6 again, a localization on an access point of the network, that is, he tries to use an access point to connect to the telecommunications network, which makes it possible to exchange voice signals over Internet connections. The various events that occur are in the localization phase 24 of the 2 shown. At this stage will be an application 240 from the second base unit 3 to the mobility server 7 sent. The mobility server 7 recorded after a study of the database 8th that the telephone has already been registered on another base. Consequently, the request becomes 240 now interpreted by the mobility server as a request to search for a localization.

Before accepting the location of the telephone set on a new base unit, an identification step is initiated. For this purpose, it allows an application 241 Called key transfer request, the mobility server 7 to transmit to the second base unit the secret key corresponding to the telephone set which sent the request for locating. A data exchange 242 will now be between the second base unit 3 and the telephone set. This data exchange complies with the DECT protocol and makes it possible to precisely identify the telephone set. The authentication mechanism used in this data exchange is as follows: the second base unit transmits a random number to the telephone set; it encodes the random number with the help of its secret key and sends to the second base unit the result of the encryption process. The second base unit, in turn, also has the random number using the secret key given to it by the mobility server by the request for transmission of the key 241 sent encrypted. The comparison between the results of the two ciphers makes it possible to judge the authenticity of the telephone set.

If the authentication step turns out to be satisfactory, an application will be made 243 from the second base unit 3 to the mobility server 7 sent. This application informs the mobility server 7 about the fact that the telephone was just located at this base unit. The mobility server 7 can now the database 8th update to save the new position of the telephone set. The application 243 is thus an application for confirmation of localization. For this purpose, the method according to the invention uses a message of the protocol, which deviates from its usual use. For example, in the case of the MGCP protocol, the application uses the reserved command RSIP (ReStart in Progress). This command is commonly used by this protocol to indicate that a telephone set is requesting reinitialization on the telecommunications network, for example after a previous shutdown. The application for confirmation of localization 243 is thus sent in the form of an application for reinitialization. A proposal 244 from the mobility server 7 to the central server 1 makes it possible to inform the latter that the telephone set has sent a request for confirmation of the location. Again, the command used in the MGCP protocol is the RSIP command. A proposal 245 from the central server 1 to the mobility server 7 is sent, and then an application 246 from the mobility server 7 to the second base unit 3 sent, now make it possible to acknowledge the request for confirmation of the localization as registered.

The phase of initialization 25 of the access point, which of the second base unit 3 is formed by the central server 1 can start now. For this purpose, an application 250 comprising a set of commands suitable for reinitializing the telephone set from the central server 1 to the mobility server 7 then submit an application 251 that is similar to the previous one from the mobility server 7 to the second base unit 3 transfer. Quittieranträge 252 and 253 that from the second base unit 3 or the mobility server 7 to the mobility server 7 or the central server 1 are now dispatched to approve the reinitialization process.

• – nach dem Registrierereignis 230 umfaßt der Antrag auf Mitteilung der Registrierung den Befehl: „o: dect/register (Geheimschlüssel)„.
• – der Antrag zur Suche nach einer Lokalisierung 240 umfaßt den Befehl: „o: dect/loc_rq„.
• – als Antwort auf die Suche nach Lokalisierung umfaßt der Antrag auf Übertragung des Schlüssels 241 den Befehl: „X+UAK: (Geheimschlüssel)„.
• – unter den Befehlen der Anträge 250 und 251 ist der Befehl „RQNT„ (für ReQuest NoTify) zu finden.

In the MGCP protocol, the syntax of certain requests follows the following rules:

• - after the registration event 230 The application for notification of registration includes the command: "o: dect / register (secret key)".
• - the request to search for a localization 240 includes the command: "o: dect / loc_rq".
• - in response to the search for localization, the request for transfer of the key includes 241 the command: "X + UAK: (secret key)".
• - under the orders of the applications 250 and 251 you can find the command "RQNT" (for ReQuest NoTify).

The inventive method can be used automatically whenever a telephone set changed over from a first Abdeckzone in a second Abdeckzone.

Claims (6)

Method for managing the mobility of a telephone set ( 6 ), which belongs to a cordless telecommunications network, this network in particular a central server ( 1 ), a mobility server ( 7 ) and a set of base units ( 2 ; 3 ) to which one or more telephone sets are connected, each telephone set being connected by a connection to a first base unit ( 2 ) to a connection to a second base unit ( 3 ), whereby the central server ( 1 ) and the base units ( 2 ; 3 ) communicate according to a master / follower type protocol to perform the data-related communications on Internet connections, characterized in that it comprises the following stages comprising: - on the first base unit ( 2 ) to record an application to register a telephone set ( 230 ); - a request to notify the registration ( 233 ) from the first base unit ( 2 ) to the central server ( 1 ) connected mobility server ( 7 ) transferred to; - a database ( 8th ) of the mobility server ( 7 ) to update ( 234 ), in which in the database ( 8th ) identification information (A) indicating the telephone set that sent the registration request, and location information (C) representing the second base unit ( 3 ) indicates to be connected; On the second base unit ( 3 ) request a localization request ( 240 ) of the telephone set on this second base unit ( 3 ) capture; - a request for the transfer of the secret key ( 241 ) between the mobility server ( 7 ) and the second base unit ( 3 ) with regard to authentication ( 242 ) of the telephone set; - a request for confirmation of localization ( 243 ) from the second base unit ( 3 ) to the mobility server ( 7 ) transferred to; - from the mobility server ( 7 ) to the central server ( 1 ) a proposal ( 244 ) indicating that the telephone set has sent a request for confirmation of the location within the telecommunications network; - from the central server to the second base unit a set of applications ( 250 ; 251 ) to reinitialization. Method for managing the mobility of a telephone set belonging to a cordless telecommunications network according to Claim 1, characterized in that the request for confirmation of the location ( 243 ) in the form of a request for reinitialization. Method for managing the mobility of a telephone set, which belongs to a cordless telecommunications network, after one of the preceding ones Claims, characterized in that the Communication protocol between the central server, the mobility server and the various base units is the MGCP protocol. Method for managing the mobility of a telephone set, belonging to a cordless telecommunications network according to claim 1 or claim 2, characterized in that the Communication protocol between the central server, the mobility server and the various base units is the MEGACO protocol. Method for managing the mobility of a telephone set belonging to a cordless telecommunications network according to one of the preceding claims, characterized in that the authentication of the telephone set takes place in particular by means of a digital secret key (B) corresponding to the identification information in the database ( 8th ) of the mobility server ( 7 ). Method for managing the mobility of a Telephone apparatus belonging to a cordless telecommunications network according to one of the preceding claims, characterized in that the various applications between the base units, the central server and the mobility server are transmitted through Internet connections.