Method for call connection to a radio subscriber

p0001The invention relates to a method for establishing a call connection for calls to a mobile subscriber according to the preamble of claim 1.

p0002In transnational GSM mobile radio system (Global System for Mobile Communication) with several mobile networks of different network operators get calls that are initiated by a subscriber of a fixed network or a mobile network from outside the home mobile radio network of the called mobile subscriber, through international telecommunications networks to a called for the radio subscriber responsible mobile switching center (Gateway mobile switching Center) in its home mobile radio network. The mobile switching center initiates a location request to a central subscriber database (Home Location Register), of which a request (provide roaming number) directed to transmit a mobility number (Mobile Subscriber Roaming Number) to a for the called mobile subscriber currently competent decentralized subscriber database (Visitor Location Register) becomes.

p0003The introduction of non-standard network operator specific services in the various countries where the GSM network is leading to new demands on the network devices, insbesonder to the mobile switching centers and subscriber databases. Due to several network operators - also within a GSM country - it may happen that not all mobile switching centers in the network or on the networks the entire network operator specific services of services spectrum, which of the provided for each arriving in net calls mobile switching center (Gateway Mobile Switching Center) calls for support.

p0004For an optimized connection (Optimized Routing), for example, the location request can be directed from a foreign power directly to the central subscriber database in the home mobile radio network of the called mobile subscriber. If the calling party a fixed network subscriber, as well as a location request from a landline is possible provided between the two networks has been agreed the possibility of optimized connection. However, the direct connection can not be used when the called mobile subscriber is treated as a participant of an intelligent network with the possibility of use of those services in the intelligent network. The interaction of bodies of the GSM mobile radio network with facilities of an intelligent network is network-specific, so that the use of services in the intelligent network is only possible between each country's own mobile network and the means of the intelligent network. One is not realized.

p0005Object of the present invention is to provide a method of establishing a call connection for calls to a mobile subscriber, through a cross-network treatment uniform net-specific services is possible.

p0006This object is achieved by the features of claim 1. Further developments of the invention are specified in the subclaims.

p0007Upon receipt of the location request checks the central subscriber database, whether the requesting switch can support the entire service range, and sends a negative test result, a request containing additional information and the mobile subscriber number of the called mobile subscriber, to a decentralized subscriber database from which to the services spectrum of support and for receiving incoming calls provided mobile switching center belongs. Both information are stored in the decentralized subscriber database, based on the request returns in response a mobility number with a reference to the stored information. Once a building the call connection triggering message is received with the referring to the additional information Mobility number in the home mobile network, the mobile switching center establishes a second location request with the stored radio subscriber number to the central subscriber database. With the mobility number provided on the re-location request, the call connection is established from the mobile switching center.

p0008By the invention a called mobile subscriber can across networks and regardless of the individual network operator specific services, a service range, consisting of multiple services, are provided uniformly available. The call connection is established from a the services spectrum supporting mobile switching center, after the incoming in the mobile network call was redirected to by sending the additional information in the request and by starting a second location request, which has a transmission of the mobility number with reference to the additional information the consequence.

p0009According to another embodiment, the request is sent with the additional information to the mobile subscriber currently competent decentralized subscriber database at residence of the called mobile subscriber in the home mobile radio network, which belongs to a the services spectrum supporting mobile switching center.

p0010According to another embodiment of the invention is directed with reduced support the range of services by the associated mobile switching center, the request with the additional information to a defined decentralized subscriber database in its own mobile network in residence of the called mobile subscriber in a mobile data network or in a location area of ​​the home mobile radio network, to a the services spectrum supporting mobile switching center belongs.

p0011The review of the interrogating switching equipment to support the range of services is carried out in accordance with an embodiment of the invention by comparing a transmitted in the location request address to identify the switching device of the calling subscriber with a stored in the central subscriber data base address to identify a the services spectrum supportive switch. It is advantageous if the central subscriber database for comparison contains a list of the mobile switching centers that support the services spectrum.

p0012It is advantageous if the additional information consists of a virtual international mobile subscriber telephone number that can be allocated to a real radio subscriber.

p0013The invention is explained with reference to an embodiment shown in FIGS.

p0014In detail:<dl id="dl0001" compact="compact"><dt>Fig. 1</dt><dd>a block diagram of establishing a call connection with a call from a foreign network and residence of the called mobile subscriber in his home mobile radio network,</dd><dt>FIG. 2</dt><dd>a block diagram of establishing a call connection with a call from a foreign network and residence of the called mobile subscriber in another network,</dd><dt>Fig. 3</dt><dd>a block diagram of establishing a call connection with a call from the home mobile radio network and residence of the called mobile subscriber in his home mobile radio network and</dd><dt>Fig. 4</dt><dd>a block diagram of establishing a call connection with a call from the home mobile radio network and residence of the called mobile subscriber in another network.</dd></dl>

p0015Figure 1 shows the block diagram of establishing a call connection with a call, which is initiated by a mobile subscriber of a mobile network PL1 and directed to a mobile subscriber in a home mobile radio network PL2, in which the mobile subscriber is registered. Of the two mobile networks PL1 and PL2 different mobile areas each with its own network operators in the transnational GSM mobile radio system (Global System for Communication) are covered. It is an optimized connection (Optimized Routing) between the calling mobile subscriber and the called mobile subscriber - between two mobile networks PL1 and PL2 - as agreed, so that from the foreign network PL1 a location request (Interrogation) directly to a central subscriber database (HLR) in mobile network can be addressed PL2 of the called mobile subscriber. If the calling party a fixed network subscriber, as well as a location request from the associated fixed network is possible provided between the two networks, the use of the optimized connection is agreed.

p0016The location request SRI is with the called mobile subscriber associated with international mobile subscriber number MSISDN of a disposed at the interface to other networks in the mobile network PL1 mobile switching center GMSC1 (Gateway Mobile Switching Center) to the central subscriber database HLR (Home Local Register) emitted in the mobile network PL2 (1) , The mobile network PL2 is the home mobile radio network of the called mobile subscriber, in which the central subscriber database HLR is arranged for storing the subscriber data of all registered in the mobile network radio subscriber. The location request SRI also address de the calling mobile subscriber and the requesting mobile switching center GMSC1 be of the interrogating Mobile Switching Center GMSC1 transmitted, in order to discern whether the requesting mobile switching center is arranged from the perspective of the called mobile subscriber in its own wireless network or not.

p0017In the central subscriber database HLR a control character is reserved for each mobile subscriber, which indicates whether a particular service such as the optimized connection or more services of a service spectrum can be used by each mobile subscriber. The entire spectrum of services, or feature can be set only for the mobile network in the respective GSM country and should still be used when a call from a foreign network via the network boundary. An example of a feature (CAMEL) to support network-operator-specific services is from "The CAMEL feature, Proposed revisions to the stage 1 description" of ETSI / STC / SMG1, 03.14.95, GSM 02.78, version 0.4.0, pages 1 -19 known. The central subscriber database HLR has a list of mobile switching centers, one of which, for example, this feature is supported.

p0018The central subscriber database HLR verified using the information provided in the location request SRI the polling mobile switching center GMSC1 whether the location request from outside the mobile network PL2 or from a mobile switching center in the mobile network PL2, respect for the limited functionality of the support of the entire service spectrum can be detected, triggered has been. The check is made by comparing the received address with the address stored in the list.

p0019If the called mobile subscriber is located in a local residence area, which is managed by a mobile switching center GMSC2 with associated decentralized subscriber database VLR2 the home mobile radio network PL2, and this mobile switching center GMSC2 supports the entire service spectrum, is the central subscriber database HLR a request PRN for decentralized subscriber database VLR2 emitted (2). With the request PRN additional information RRI and from the requesting mobile switching center is GMSC1 sent international mobile subscriber number also transmitted MSISDN of the called mobile subscriber. The additional information RRI and the mobile subscriber number MSISDN stored in the decentralized subscriber database VLR2, from a mobility number MSRN establishing the whereabouts of the called mobile subscriber returned in response to the request to the central subscriber database HLR (3). In this table the decentralized subscriber database containing VLR2 in a more mobility numbers is created, an entry which points to the stored additional information RRI and the stored radio subscriber number MSISDN.

p0020Upon receipt of the MSRN Mobiltätsnummer directs the central subscriber database HLR that number for interrogating Mobile Switching Center GMSC1 further (4). A message IAM (Initial Address Message) containing the mobility number MSRN, to the start of the construction of the call connection is transmitted from the mobile switching center GMSC1 to a switching device VE 1 in a fixed network PS1 (5). The landline PS1 is the public switched telephone network that exists in the country of the mobile network PL1. Similarly, there is an existing in the country of the mobile network PL2 landline PS2, which is also made from a public telephone network. In the fixed line PS2 a switching device VE2 is arranged which receives the message IAM with the mobile subscriber telephone number MSRN (6) and forwards it to the mobile switching center in the mobile network GMSC2 PL2 (7). Thus, from the Mobile Network PL1 on both landlines PS1 and PS2 to the wireless network PL2 a call connection has been iniiert.

p0021Since arriving in the mobile switching center GMSC2 Mobililtätsnummer MSRN shows the information stored in the associated subscriber database VLR2 Additional Information RRI - recognizable by the contents of Mobiliätsnummern table - a second location request SRI 'to the central subscriber database HLR is emitted. The new location request SRI 'contains the information stored in the decentralized subscriber database VLR2 international mobile subscriber number MSISDN. The mobile switching center GMSC2 is a switching device in the home mobile radio network PL2 of the called mobile subscriber, from the entire spectrum of services is supported by the network-specific functions and services.

p0022From the home location register HLR a request PRN is due to the second location request SRI 'again directed to the subscriber database VLR2 (9), so that the mobility number MSRN to the home location register HLR is sent as a response (10). The mobility number MSRN is transmitted along with a service code SCM to mobile switching center GMSC2 (11). At the incoming service code SCM detects the mobile switching center GMSC2 that a branch should be performed in a service control point SCP of an intelligent network to be forwarded by the service control point SCP information regarding the use of Intelligent Network services to the switching device in the mobile network PL2. As a mobile network based on the GSM standard supports the structure of an intelligent network, and thus the mobile switching center GMSC2 can be regarded as a service switching point SSP of an intelligent network, information IND will be sent to the service control point SCP (12) and received in the opposite direction from the service control point SCP (13 ).

p0023Providing the service identification SCM from the central subscriber database HLR, in which the service identification SCM is registered as a subscriber-individual subscriber date, and the subsequent dialogue with the control point SCP of the intelligent network is used for the use of Intelligent Network services for mobile subscriber of a mobile network. This can be linked to an extended service package with Intelligent Network services and used across networks in the mobile network for wireless subscriber has ended rich services (supplementary services).

p0024The additional information RRI that is sent in the request PRN together with the international mobile subscriber number MSISDN of the called mobile subscriber for decentralized subscriber database VLR2, consists of either a virtual radio station number or a new parameter within as additional information for the identification of a desire for re-location request of home mobile radio network of the called mobile subscriber is used. In the decentralized subscriber database VLR2 can be set for the received additional information RRI a control character that when evaluating the number of mobile subscriber number is evaluated. If the control characters are occupied, the stored radio subscriber number MSISDN is read and re-digits review with the result of re-location request SRI 'performed.

p0025Figure 2 shows the block diagram of establishing a call connection with an arriving from the mobile network PL1 call directed to a mobile subscriber, which is outside of his home mobile radio network PL2 in a foreign mobile network PL3. In this case, the central subscriber database HLR sends the request PRN with the additional information RRI and the international mobile subscriber number MSISDN to a defined mobile switching center GMSC2 'with associated decentralized subscriber database VLR2', the according to the list contained in the home location register HLR, the entire service spectrum can be supported. Likewise a suitable mobile switching center in the home mobile radio network is PL2 of the called mobile subscriber for the request PRN selected when the called mobile subscriber is located in a residence area whose mobile switching center has limited functionality relative to the total services spectrum.

p0026In the list, for example, for the function of the direct call connection (Optimized routing) possible only when adequate decentralized subscriber database per central subscriber database and per mobile data network to be registered, provided between the networks into an agreement for the implementation of this function is given. The rest of the connection setup is identical to those given in the schematic diagram of Figure 1 measures (3) and (4) during the signaling and (5, 6) and (7) as part of the path setup (routing). The selected from the list mobile switching center GMSC2 'receives the message IAM with mobility number MSRN and initiated because of the decentralized subscriber database VLR2' Additional Information RRI and mobile subscriber number MSISDN, referenced by the received mobility number MSRN stored, the second location request SRI '(8). With the renewed location inquiry SRI 'to the central subscriber database HLR stored radio subscriber number is transmitted MSISDN of the called mobile subscriber.

p0027From the home location register HLR a request PRN is addressed to the mobile network PL3 with for the called mobile subscriber is currently responsible mobile switching center VMSC and the associated decentralized subscriber database VLR (9) that the response to the request PRN the whereabouts of the called mobile subscriber festlegenede mobility number MSRN subscriber database HLR returns (10). The mobile switching center VMSC and the decentralized subscriber database VLR attend a local residence area known to be the home mobile network situated in the other mobile network PL3 PL2 of the called mobile subscriber and in which the called mobile subscriber is currently located. The other connection is established, as indicated in the schematic diagram of FIG. 1 This means that is made over the defined to support the entire service spectrum mobile switching center GMSC2 'in the mobile network PL2 connect to the service control point SCP of the intelligent network in order to use the services of the intelligent network can. The branch will be taken on the basis of data provided by the central subscriber database HLR service identification SCM, and conducted a dialogue between the aufzufassenden as service switching mobile switching center GMSC2 'and the service control point SCP.

p0028Figure 3 shows the block diagram of establishing a call connection when a call is directed to a called mobile subscriber within a single mobile network PL1 'from a calling radio subscriber. In this case, the called mobile subscriber is in his home mobile radio network similar to the connection described in FIG 1. Since reside both wireless devices in the same wireless network, the construction of the call connection via a single toll PS1 is enough 'with associated switching device VE 1' which 'represents a public switched telephone network in the country of the mobile network PL1. Due to several operators of a mobile network PL1 'in one country, it can happen that not all mobile switching centers are suitable to support the full functionality and the entire service spectrum.

p0029In this case, the forwarding of the call connection by the central subscriber database HLR is performed according to the above-described measures to the mobile switching center GMSC2 with the decentralized subscriber database VLR2 within the mobile network PL1 '. The transmission of the additional information RRI in the request PRN, storing the additional information RRI and the mobile subscriber number MSISDN in the subscriber database VLR2, the reference to the information stored in the Mobiltätsnummern table of subscriber database VLR2 and triggered upon receipt of a Mobitätsnummer MSRN second location request SRI ' with subsequent transmission of mobility number MSRN for the localization of the calling mobile subscriber and the preparation of a compound of receipt of the service code SCM to the service control point SCP of the intelligent network as described above are subsequently executed.

p0030The block diagram shown in Figure 4 shows a connection for a call connection similar to the block diagram of Figure 2 except that the called radio subscriber does not reside in the mobile radio network PL1 'but in the mobile network PL3, or that the charge of the called mobile subscriber mobile switching center to support spectrum of the entire services is not suitable. Therefore, a compound is added to the full service spectrum supporting mobile switching center GMSC2 'with associated decentralized subscriber database VLR2' in mobile radio network PL1 'constructed to have a dialogue with the service control point SCP of the intelligent network after receiving the mobility number MSRN can. The new location request SRI 'takes place as a result of the data stored for incoming mobility number MSRN Additional Information RRI and includes the time allotted for the called mobile subscriber international mobile subscriber number MSISDN. The remaining end of the connection setup can be found in the actions described in FIG. 2