EP0742990A1

EP0742990A1 - Communication system with mobile telephones and process for operating the same

Info

Publication number: EP0742990A1
Application number: EP95936927A
Authority: EP
Inventors: Peter Lietha; Eugen Rippstein
Original assignee: Siemens Albis AG
Current assignee: Siemens Schweiz AG
Priority date: 1994-12-05
Filing date: 1995-12-01
Publication date: 1996-11-20
Also published as: WO1996018274A1; US5983096A

Abstract

A communication system has an ISDN exchange (VSTa) to which is connected at least one special terminal (SE) provided with electro-acoustic transducers (MIC, LS) and associated with a mobile part (MT). The special terminals (SE1, ..., SEn) have a processor (MP) and a through switching unit (SWUe) that allows a connection to be established between a terminal (EGx) and the mobile part (MT1; MT2; ...) associated to the special terminal (SE1; SE2; ...). In order to establish the communication between the mobile part (MT1; MT2; ...) and the terminal (EGx) through the through switching unit (SWUe), the target address of the terminal (EGx) is transmitted to the special terminal (SE1; SE2; ...) so that the special terminal (SE1; SE2; ...) may receive this information and establish the connection. The special terminal (SE1; SE2; ...) further has speech monitoring means and/or telephonic conversation recording means. All conversations of the bearer of the mobile part (MT) may thus be heard at his workplace. Telephonic conferences may also be switched or the mobile part (MT1; MT2; ...) may trigger functions (conversation recording, alarm, etc.) of the special terminal (SE1; SE2; ...) by remote control.

Description

Communication system with mobile phones and operating procedures

The present invention relates to a communication system according to the preamble of patent claim 1 and a corresponding operating method according to claim 7.

The cordless telephone systems known today allow the subscriber to conduct his calls independently of his work place. Systems with a base station that a handset e.g. Is permanently assigned via a secret code number, normally have a range of 30m in buildings to 300m outdoors. Other systems have base stations located in different service zones, with which a handset automatically connects as soon as it comes within range. Relevant information such as phone number, saved numbers, accrued charges, battery status, etc. is normally displayed on the handsets. Based on this concept, base stations can be installed discretely outside of the participant's sight and range bets. From WO-A-90/12469 a cordless telephone system is known in which there are fewer base stations than mobile parts. The change of a handset into the radio range of another base station is updated via the features of call forwarding and call forwarding provided by the extension communication system (PABX). The base stations described in EP-A-0 569 061 can also be provided with several identifiers, so that several mobile parts can come into contact with a base station or individual mobile parts with different base stations. For the participant and his work environment, it does not matter which base station the call is handled. Communication takes place exclusively between the wearer of the handset and another subscriber. Third parties neither have access to the call-specific data, nor are they able to listen to the transmitted voice signals or to start a conference call. This is particularly disadvantageous if the carrier of the mobile part is a member of a working group within which a fast and smooth data exchange is important.

The present invention is therefore based on the object of providing a communication system with mobile telephones or mobile parts to which at least one e.g. A terminal provided at a work station is assigned, via which further authorized subscribers can access data and / or voice signals from a conversation which is carried out by the carrier of the mobile part with another subscriber. A corresponding operating procedure should also be specified.

This object is achieved by the measures specified in claim 1 or 7. Advantageous embodiments of the invention are specified in further claims.

The communication system according to the invention enables the wireless connection of the mobile part to base stations of public or private telephone networks. This results in a maximum realm bet for cordless communication. At the workplace, the participant can either use the stationary end device or get in touch with a weather participant via the handset. The channels used by the carrier of the mobile part are routed in both directions over the stationary terminal, so that all essential data of the connection dialed, for example, by the mobile part can be accessed via the stationary terminal. The solution according to the invention can be used particularly advantageously in a communication system, as described in WO-A-92/17013.

The invention is explained in more detail below with reference to a drawing, for example. It shows:

1 shows a communication system according to the invention. FIG. 2 shows the communication system of WO-A-92/17013 which has been weathered by the solution according to the invention

1 shows a switching center VSTa provided with a switching unit SWUa, on which stationary terminals or special terminals SE1 SEn e.g. are connected via glass fibers and an interface or a server S. Each of these special terminals SE1 SEn is preferably connected to a mobile terminal or mobile part MT1; ...; MTn provided. These mobile parts MT1 MTn can be transmitted via radio or base stations BS1, ..., BSm, which are connected via appropriate server modules CSV to associated central units VSTa VSTx, with any end devices, e.g. with a terminal EGx connected via a terminal adapter TA with the central communication unit VSTa. contact. The distribution centers VSTa VSTx are e.g. directly (via a voice highway

HWY) or connected via the public or a private network. The coupling of the

Mobile parts MT1 MTn to the base stations BS1 BSm and any necessary zone changes are carried out using known methods, e.g. in P. R. Gerke, digital communication networks, Springer Verlag, Heidelberg 1991, chapter 6.7. See also the relevant recommendations of the CEPT (Conference Europ. Des Administrations des Postes et Tέlecommunications) • GSM group (Graupe Speciale Mobile).

The special terminal SE1 shown in FIG. 1 and connected to the switching center VSTa via at least one basic connection (see Kanbach, Körber, ISDN die Technik, Hüthig Verlag, Heidelberg 1990, page 34) is with a processor MP, with software modules SE-SW , MH-SW, a keyboard KB, a display DISP and all other essential functions of a digital terminal. Such terminals are described in Kanbach, Körber, ISDN, Technik, Hüthig Verlag, Heidelberg 1990, Chapter 7. On page 265, for example, a comfort telephone is shown which is constructed with known integrated circuits. A workstation, as shown on page 243, can preferably also be used as the terminal. With the software modules SE-SW, MH-SW, the connection setup to the mobile part MT1 or to the special terminal SE1 is regulated in the manner described below. The special terminal SE1 can also be connected to electro-acoustic transducers (microphone MIC and loudspeaker LS) or a recording device TB via contacts K1, K2 and K3, which are actuated by the processor MP. The special terminal SE1 also has a switching unit SWUe, through which at least the B channels shown in FIG. 1 can be interconnected. According to the invention, the terminal devices SE1,... SEn are therefore connected as terminal devices or as switching centers to corresponding connections of the switching center VSTa. The choice of the connection depends on the operating method used.

The communication system shown in Fig. 1 works as follows. A e.g. The incoming call from the terminal EGx is signaled in the special terminal SE1 (the procedure for establishing and clearing down connections between ISDN terminals is, for example, in Kanbach, Körber, ISDN technology, Hüthig Vertag, Heidelberg 1990, chapter 5.1 or in P. Bocker, ISDN the integrated services digital night network, Springer Vertag, Heidelberg 1990, chapter 4.3.5.1). The processor MP of the special terminal SE1 is e.g. programmed by the subscriber via the keyboard KB in such a way that the ringing tone is output on the special terminal and / or on the mobile part MT1. For this purpose, the ringing tone is switched through to the loudspeaker LS and / or a connection to the mobile part MT1 is established by the special terminal SE1 via the switching center VSTa. To transmit the voice signals from the terminal EGx to the mobile part MT1, the voice channel (B1) of the incoming call in the special terminal SE1 is connected by the switching unit SWUe with a still free voice channel (B2). The connection to the mobile part MT1 can optionally only be set up if the subscriber does not answer the call via the special terminal SE1 (handset off).

If the subscriber from the MT1 handset e.g. the end device EGx wants to call, the connection is always established via the special end device SE1, which in turn connects the two B channels and the exchanged voice signals e.g. can copy to the speaker LS for listening or for voice monitoring. Et al Measures for the voice monitoring of telephone calls and for the formation of conference calls are known to the person skilled in the art from CH-PS 681 409.

If the special terminal SE1 is connected to a subscriber line of the central exchange VSTa, the following method steps are provided for establishing a connection from and to the mobile part MT1, which are basically in P. Bocker, ISDN the integrated service digital message network, Springer Vertag, Heidelberg 1990, chapter 4.3 .5.1, Figure 4.23 are shown. From this it can be seen that after the dialing process, a calling end device always sends a SETUP message to the network, which is based on the contracts in PR devices, digital communication networks, Springer contract. Heidelberg 1991, page 360, Table 7.5 elements listed. This contains data fields for the origin address (origination address), the destination address (destination address) and normally also for user-user information (user-user information) that are not interpreted by the network (with regard to user-user signaling see P. Bocker, ISDN the integrated service digital message network, Springer publishing company, Heidelberg 1990, chapter 4.3.5.5). The first step in establishing a connection between the terminal EGx and the mobile part MT1 is that a connection to the special terminal SE1 is first established in a known manner. For the further connection, the special end device SE1 is required the destination address of the terminal to be called. This address is known to the special terminal SE1 if the handset MT1 is to be called. If, however, the terminal EGx is to be called, its destination address is written in the mobile part MT1 as user-user information in the SETUP message. If the possibility of entering user-user information is missing, the ISDN interface also makes it impossible to insert a called-party number (ISDN message element which contains the call number of the called subscriber). Instead of the control functionally via ISDN protocols, control routines can also be triggered in the switching center by means of stimulus terminals.

It is also possible to transmit the target information using the multi-frequency method (see P. R. Gerke, digital communication networks, Springer Vertag, Heidelberg 1991, Sette 5) via the voice channel. The processor MP provided in the special terminals SE1 provides e.g. The originating address determines that a call has arrived from the handset. The signals arriving via the voice channel are then checked, which may contain instructions for weather transmission and the telephone number of a terminal EGx. The field of the target address of the SETUP message remains reserved for the target address of the special terminal SE1.

In the SETUP message compiled by the special terminal SE1, the number of the terminal EGx transmitted as user-user information or with the multi-frequency method (DTMF) is entered in the field of the destination address, so that a connection to the terminal EGx is established in a known manner can. The special terminal SE1 is therefore connected to the calling and the called terminal EGx, MT1 at this point. The connection of the voice channels B1, B2 belonging to these connections enables the terminals EGx and MT1 to exchange information. Basically, therefore, a connection is first established from the calling terminal to the special terminal SE1 and then a connection from the special terminal SE1 to the called terminal. So that the origin address of the calling terminal EGx can be displayed in the mobile part MT1, this must be taken from the incoming SETUP message in the special terminal SE1 and the outgoing SETUP message must be transmitted. In principle, the special terminal SE1 could also accept the incoming SETUP message and write the destination address of the handset MT1 or the terminal EGx in it.

Instead of specifying a destination address for a terminal EGx, the handset MT1 can of course only request a connection to the special terminal SE1. This can e.g. by means of a message in the field user-user information. For the sake of simplicity, however, the field user-user information is left empty, from which the special terminal SE1 can see that no weather connection is desired.

The destination address π or phone numbers of the special terminal SE1 and the handset MT1 must therefore be different. However, it is sufficient if the destination address of the mobile part MT1 only the special the terminal SE1 is known, since connections to the mobile part MT1 are always established via the special terminal SE1.

The service and voice signals exchanged between the terminals EGx and MT1 can therefore be evaluated in the special terminal SE1. Furthermore, in a preferred embodiment of the special terminal SE1, the voice signals can be mixed with other voice signals, so that the switching of conference calls can be made possible. For this purpose, the switching unit SWUe is connected to a conference module CONF, so that e.g. All participants in a work group to which the bearer of the MT1 handset belongs can start a conference call. For example, the MUSAC integrated circuit from Siemens AG can be used as the CONF conference module, which basically has the functions of a signal processor. A building block of this type offers the possibility, in a processor-controlled manner, to mix all of the highways of several highways as desired.

If the special terminal SE1 is connected to a connection for switching centers at the switching center VSTa, the connection is established between the terminal EGx and the mobile part MT1 by completely writing the phone number in the field for the destination address of the SETUP message. So that the special terminal SE11, which acts as a switching center, is included in the connection establishment when searching for a route, its address must be included as part of the destination address. If e.g. a connection to the terminal EGx is established from the mobile unit MT1 via the base station BS1, the switching center VSTa and the special terminal SE1, the mobile unit MT1 manually or automatically first dials the number of the special terminal SE1 and then the number of the terminal EGx into the field for the destination address of the SETUP message is written. Since the special terminal SE1 acts as a central exchange and not as a terminal in the network, it connects the connection without changing the number of the terminal EGx. Nevertheless, there are options in the special terminal SE1 for listening in or for making a conference call.

The processor MP of the special terminal SE1 preferably always checks the origin address in the corresponding field of the incoming SETUP message. If the source address corresponds to the address of the handset MT1, the processor MP determines whether the handset MT1 in the B channel e.g. instructions from the subscriber arrive by means of the multi-frequency method or via the user-user information (or further transmission channels available). Basically, this enables Fe control of the workplace (activation of β-electro-acoustic transducers, recording of calls, retrieval of recordings, switching of standard conferences, line selection, etc.).

Instead of the decentralized arrangement of the processor MP, the switching unit SWUe and, if present, the conference module CONF in the special terminals SE, these elements can also be used the server module S are arranged. These components (MP, SWUe, CONF) are then not only available to a single, but to several special terminals SE connected to the server module S at the same time. This also facilitates mutual data access for voice monitoring and the formation of conference calls.

2 shows the communication system known from WO-A-92/17013, which additionally has a server module CSVR, which is connected to two base stations BS1, BS2. The communication system basically consists of a switching center VST which is equipped with server modules SLMA, SLMB for conventional terminals, with server modules SLMT for special terminals SE, with a server module CSVR for mobile parts MT, with a server module ST for a system manager SM and with a interface module SB is equipped, via which weather public or private communication systems are accessible. The special terminals SE11 SEn connected via the concentrator modules DDBC to the switching center VST are devices DDB (DIGITAL DEALER

BOARD) with keyboards, of which several keys are programmable in such a way that a desired connection can be initiated by pressing a key. Such communication systems, which provide various special, not generally common performance features, are e.g. used in banks, stock exchanges or other branches of trade. One area of application is, for example, international trading in stocks, foreign exchange, commodities, which is not just world-wide communication for decision-making. but also requires direct, active intervention in the market. The use of these systems in police stations, the fire brigade or in energy supply centers is of no less importance. With the communication system according to the invention, the head of operations stationed in the control center is always able to monitor and record the entire communication of the officers in the area of operation.

The central component of the switching center VST is a shadow-through unit SWU, in which all the central units serving to switch connections as well as a central control necessary for this are integrated. The switching unit SWU is also connected to the server modules SLMA, SLMB, STMD and to the interface module SB. The communication system is integrated into public communication networks in accordance with the ISDN system; the SB interface module must ensure this integration by providing special data formats. The switching unit SWU is connected to integrated servers S1 ... Sn via central bus systems. The server modules SLMA and SLMB connected by the shadow-through unit SWU serve to provide the BORSCHT functions which are generally known in switching technology for the conventional analog or digital subscriber terminals. The server module STMD carries out adjustments, for example in the event of necessary configuration changes, between the communication system and the system manager SM. The switching servers are special peripheral modules, in the following server modules SLMT11 SLMT44; SLMT Z1 called SLMT Z4, realized. They are integrated decentrally in the communication system by inserting them instead of the SLMB I / O modules. The system-compliant integration requires adaptation measures at the hardware and software interfaces concerned, which will be discussed later. With a higher degree of expansion of the dealer system, the switching servers are preferably arranged in system groups. Four individual system groups with four switching servers each are preferably assigned a central system group with four switching servers.

In a first expansion phase, for smaller teams of dealers, only a single system group with several, e.g. Four server modules SLMT11, ..., SLMT14 are used, which are interconnected via data paths D and / or a central server module SLMT Z1. In the next stages of expansion, weather system groups with four server modules each SLMT21 SLMT24; SLMT31, ..., SLMT34;

SLMT41 SLMT44, can be added. According to the invention, these four individual system groups can be networked directly via additional data paths and / or via an additional, central system group with server modules SLMT Z1, ..., SLMT Z4. Each of the four individual system groups is connected to one of the server modules SLMT Z1 connected to one another via data paths D.

SLMT Z4 of the central system group Ober Linien ü connected. The maximum number of SLMT server modules per individual system group is determined by the capacity of the shadow-through SWU used on the server modules. From each system group, for example, up to m lattices (and an HDLC signaling letting) can be connected to the central system group. A system group thus has access to m common lines. The central system group therefore has 4 * m connections, four of which are provided for the HDLC signaling of the individual system groups. The remaining (4 * m) connections can be used as desired for connections to the individual system groups or for common lattices. The SLMT11 SLMT44 server modules are based on output via concentrator modules DDBC with the special end devices DDB e.g. connected by Uchtwellenlettem. The concentrator assemblies DDBC are equipped with mutiplex properties to switch the data arriving from several special terminal devices DDB to a connection line to one of the server modules SLMT11 SLMT44. A PCM (pulse code modulation) method is used as the transmission method. Special terminal devices DDB can be either button-type or bi-screen-oriented terminal devices designed for the dealer workplace, which have at least one handset or further switchable electro-acoustic transducers. The special terminal devices DDB are controlled via the server modules SLMT using control procedures BS, BT.

In general, the procedures running on the server modules SLMT are stored organizationally in corresponding complexes on the server modules SLMT. The entire software relating to the SLMT server modules differentiates between procedures the operating system BS the operating technology BT the switching technology VT the security technology ST and the database DB.

While the procedures of the operating system BS control the existing system components, the procedures of the operating technology BT take on control tasks in the area

the timing synchronization to the remaining units of the communication system as well as the system reliability chain.

Trouble-free operation of each SLMT server module is ensured by the ST security technology. In particular, it ensures that errors that occur are analyzed immediately and that the system triggers appropriate reactions if necessary.

The procedures of the switching function block VT of the server modules SLMT process the actual dealer-typical performance features. Typical dealer characteristics are:

Voice monitoring, brokering, parallel call, conference call, monitoring and recording functions,

which will be discussed in more detail below. In particular, the procedures of the switching-technical function block T of the server modules SLMT carry out the conversion of the data formats arriving from the special terminals DDB into the data formats of the communication system.

In addition, a database DB is stored on each of the server modules SLMT, in which static and dynamic configuration data of the special terminal devices DDB and the server modules SLMT itself are administered. The static configuration data provide information about the equipment of the special terminal devices DDB with mobile parts MT, handsets and loudspeakers, while the dynamic configuration data convey information about the current occupancy of the handsets and the connected lattices. The databases of each SLMT server module are updated with the latest configuration data via data paths D. This means that each SLMT server module has a fully permanent image of the entire configuration of all server modules SLMT. A possible change in the configuration state of one of the server modules SLMT or one of the special terminals DDB is immediately communicated to the other server modules SLMT via data paths D. A decentralization of static and dynamic configuration data is associated with this concept. This means that, for example, when creating new performance features, any Andeningen can be carried out on the SLMT server modules with little effort, without having to intervene centrally in the procedures of the communication system.

External memory units with a data display device - hereinafter referred to as system manager SM - are connected to the communication system via the STMD interface unit and contain the configuration data for the server modules SLMT and the special terminal devices DDB. The relocation of the configuration data to external units is particularly important when the communication system has to be shadowed for maintenance work. In this case, the server modules SLMT and the special terminals DDB are loaded with the configuration data from the system manager SM when the communication system starts up, which means that the original state is restored in a short time.

This concept results in performance features which take into account the special needs of a dealer job. In particular the performance feature "voice monitoring", through which several calls e.g. The fact that a conference module can be switched to a loudspeaker takes into account the special conditions of the dealer's workplace.

An active intervention in the market must often take place in a matter of seconds. Lengthy dialing processes for establishing worldwide connections must therefore be avoided under all circumstances. For this purpose, connections to destinations can therefore be established by pressing a button on the special terminal DDB; Furthermore, directions can be specified by pressing a button and the corresponding destination can be reached by post-selection. In addition, the "brokering" feature, by means of which existing connections, for example connections to several international stock exchanges, are placed on the "HALTEN" at the dealer's workstation, is used for efficient telephone calls. The trader is therefore "potential" at his workstation with a large number connected by partners. In reality, he may have activated one, two or more connections - depending on how many handsets are available per special DDB device - and actively communicate with the corresponding partners. However, there is always the option of shadowing an actively held call in the "HOLD" state and switching to a call that is currently in the "HOLD" state and actively communicating with this partner. These switching processes are controlled from the special terminal DDB by pressing the corresponding keys or touching the corresponding field on the screen. The procedures that carry out the control processes are carried out by the procedural complexes of the switching technology VT of the server modules SLMT. What is important is of course not only the possibility of quickly contacting the dealer team externally, for example the quick call to an external stock exchange, but in particular also the possibility of quickly contacting customers to members of the dealer team. In this way, time losses are to be avoided which arise from repeated calls to various team members who are not currently present. The customer is therefore given the opportunity to choose a number with which he can call several members or a subgroup of the dealer team at the same time. If this subgroup always has a favorably chosen minimum number of members present, the customer will be able to get in touch with the team of dealers very quickly. It may also be necessary for different team members to have a conference call with the customer.

The shadowing of a customer call, e.g. is fed to the server module SLMT11, to several team members of various other system groups (without the involvement of a central system group) through the shadow unit SWU of the server module SLMT11 via direct data lines to the corresponding system groups. However, it is easy to see that, with the increasing number of additional system groups, the requirements for the capacity of the see-through SWU of each server module SLMT and the number of connections to be provided increase sharply. Therefore, a central system group with the server modules SLMT Z1 SLMT Z4 is advantageous used. It is now provided by switching technology procedures that a common connection to several system groups is established in the case of an external call forwarded to the central system group. At the same time, the signaling takes place on all corresponding system groups. The voice monitoring, the entry of further participants of the same system group into solid lattices and the switching of lines is preferably carried out on the single system group. The central system group can therefore arrange a common line for different individual system groups. These common connections created by the central system group are to be concentrated in the individual system groups, preferably on a single server module SLMT. Each of the individual system groups receives an HDLC signaling path from this SLMT to the central system group. The signaling can take place via this signaling route depending on the location of the caller from or to the central system group. The acoustic interconnection of several system groups in the central system group or individual participants in a single system group takes place in conference modules which are provided in the server modules SLMT.

Due to the requirements given in the fields of application described above (banks, fire brigade, police, etc.), the use of mobile telephones or mobile parts MT according to the invention in connection with the communication system shown in FIG. 2 is particularly advantageous. The members of the working group in question, who can be reached at any time via the mobile parts MT, are in the Ability to at least partially use the existing infrastructure at the workplace. Instructions can be sent to the special end devices SE by means of user-user information. For example, a Poüzel official can make an emergency call to the control center or have the ongoing conversation recorded. The head of operations can listen in on the conversations or create conference shadows.

The measures for realizing the solution according to the invention in the area of hardware and software correspond fundamentally to those of the communication system of FIG. 1. By using special server modules SLMT for the special end devices SE, these measures can also be implemented within the server modules SLMT. This can relieve the special end devices SE and the resources used can be used more economically. A conference module CONF or a switching unit SWU, which are arranged on a server module SLMT, can be used in this case for several special terminals SE.

As shown in FIG. 2, the special terminals SE are preferably implemented with computer systems (PC's) which, if necessary, are expanded with communication modules. An inexpensive PC that already provides essential functions required at a workstation, such as in WO 94/08430 (Programmable Telecommunication Switch for Personal Computer) explained, can be expanded to a powerful communication terminal. The hardware and software provided in the Digital Dealer Boards DDB are expertly adapted to the interfaces and the operating software of the PC.

Claims

PATENT CLAIMS

1. Communication system with an ISDN switching center (VSTa) to which at least one special terminal (SEE) provided with electro-acoustic transducers (MIC, LS) is connected via a server module (S, SLMT) and at least one mobile part (MT) for that can be set up via base stations (BS1 BSm) and associated server modules (CSVR) to the switching center (VSTa), characterized in that the special terminals (SE1 SEn), each of which has a handset (MT1

MTn) is assigned, or the associated server module (S, SLMT) is provided with a processor (MP) and a switching unit (SWUe) through which a connection between a terminal (EGx) and that of the special terminal (SE1; SE2; .. .) associated Mobitteil (MT1; MT2; ...) can be shaded and that to enable the connection from the Mobitteil (MT1; MT2; ...) via the switching unit (SWUe) to the terminal (EGx)

a) the special terminal (SE1; SE2; ...) is connected to a switching center connection of the central office (VSTa) and the destination addresses of the special terminal (SE1; SE2; ...) for route selection and the terminal (EGx) for the The destination in the mobile part (MT1; MT2; ...) can be written in the "Destination address" field of the SETUP message, or

b) the special terminal (SE1; SE2; ...) is connected to a subscriber line of the central exchange (VSTa), the handset (MT1; MT2; ...) for entering the destination address of the terminal (EGx) in the field "user User information "of the SETUP message and the special terminal t (SE1; SE2; ...) is suitable for extracting this information and for connecting the connection, or

c) the special terminal (SE1; SE2; ...) is connected to a subscriber line of the switching center (VSTa), the handset (MT1; MT2; ...) for entering the destination address of the terminal (EGx) in the ISDN message element " called party number "and the special terminal (SE1; SE2; ...) is suitable for extracting this information and for connecting the connection, or

d) the special terminal (SE1; SE2; ...) is connected to a subscriber line of the central office (VSTa), the handset (MT1; MT2; ...) for entering the destination address of the terminal (EGx) via the voice channel and the special terminal (SE1; SE2; ...) is suitable for extracting this information and for connecting the connection.

2. Communication system according to claim 1, characterized in that means for voice monitoring and / or for recording the shaded Telefonge¬ conversation are provided in the special terminal (SE1; SE2; ...).

3. Communication system according to claim 1 or 2, characterized in that a conference module (CONF) is provided in the special terminal (SE1; SE2; ...) or in the server module (S, SLMT), through which between the handset (MT1; MT2; ...), the special terminal (SE1; SE2; ...) and the terminal (EGx) can be set up for a conference call.

4. Communication system according to claim 1, 2 or 3, characterized in that the processor (MP) for evaluating the "user-user information" and / or the "origin address" of the corresponding fields of the SETUP message and for execution if necessary Instructions contained therein are suitable.

5. Communication system according to one of claims 1 to 4, characterized in that an incoming call from the terminal (EGx) on the special terminal (SE1; SE2; ...) can be signaled and at the same time to the handset (MT1; MT2; ... ) can be shaded or that a call arriving from the terminal (EGx) on the special terminal (SE1; SE2; ...) can be signaled and delayed to the mobile part (MT1; MT2; ...) can be shaded if the special terminal (SE1 ; SE2; ...) the call is not answered.

6. Communication system according to one of the preceding claims, characterized in that the special terminal (SE1; SE2; ...) provided with actuating means (KB), optical display means (DISP) and electro-acoustic transducers (MIC, LS) with the server module (SLMT), which is integrated into the communication system in such a way that

Control procedures (BS, BT) are used to control the actuating means (KB) and optical display means piSP) and data in a transmission procedure from the special terminal (SE1; SE2; ...) and from the server module (SLMT) via a server module (STMD) transferred to a system manager SM,

switching technology procedures (VT) convert the transmission formats of special information data of the special terminal (SE1; SE2; ...) into communication-specific formats and also provide basic functions of switching technology as basic building blocks of further features, and that

Communicate database procedures (DB) information about the special terminal (SE1; SE2; ...) and the server module (SLMT) using the data paths (D) to all weather server modules (SLMT11-SLMT44).

7. Communication system according to one of the preceding claims, characterized in that at least one of the special terminals (SE) is a computer system extended to a communication terminal.

8. A method for operating a communication system according to claim 1 with an ISDN switching center (VSTa) to which at least one mtt electro-acoustic transducer (MIC, LS) is provided via a server module (S, SLMT) and at least one basic connection Special terminal (SE1; SE2; ...) is connected and at least one mobile part (MT1; MT2; ...) belonging to the special terminal t (SE1; SE2; ...), for which via base stations (BS1 BSm) and Associated server modules (CSVR) connections to the switching center (VSTa) can be established, characterized in that for the establishment of connections from the Mobitteil (MT1; MT2; ...) to any end devices (EGx)

a) the special terminal (SE1; SE2; ...) is connected to an exchange of the central office (VSTa), the destination addresses of the special terminal (SE1; SE2; ...) for route selection and the terminal (EGx) for the The destination in the mobile part (MT1; MT2; ...) is entered in the "Destination address" field of the SETUP message and the incoming call from the mobile part (MT1; MT2; ...) to the special terminal (SE1; SE2; ...) is passed on to the terminal (EGx) via a shadow-through unit (SWUe), or

b) the special terminal (SE1; SE2; ...) is connected to a subscriber line of the switching center (VSTa), the destination address of the terminal (EGx) in the mobile part (MT1; MT2; ...) in the field "user-user" Information "of the SETUP message is written in and removed from it by the special terminal (SE1; SE2; ...) and used for the transfer of the call to the terminal (EGx), or

c) the special terminal (SE1; SE2; ...) is connected to a subscriber line of the switching center (VSTa), the destination address of the terminal (EGx) in the handset (MT1; MT2; ...) via the voice channel to the special terminal (SE1; SE2; ...) is transmitted, which takes this information from the voice channel and uses it for the transfer of the call to the terminal (EGx).

9. The method according to claim 8, characterized in that the mediated call in the special terminal (SE1; SE2; ...) optionally monitored and the transmitted voice or data signals are fed to an electro-acoustic transducer and / or a recording device.

10. The method according to claim 8 or 9, characterized in that in the special terminal (SE1; SE2; ...) a conference call between the Mobitteil (MTV, MT2; ...), special terminal (SE1; SE2; ...) and the terminal (EGx) is formed.

11. The method according to claim 8, 9 or 10, characterized in that the special terminal (SE1; SE2; ...) over the voice channel or a corresponding field of the SETUP message (user-user information) instructions are overtuttett by Processor (MP) are running.