DE10006819A1 - Method for roaming in mobile radio network using additional Remote Home Location Register which is integrated into calling subscriber network - Google Patents

Abstract

Calls are connected through to a subscriber or from a subscriber who stays in a mobile radio network different to the network stated in the contract. The connection does not have to be routed over the subscriber's contract network. An additional Remote Home Location Register is integrated into the network in which the calling subscriber stays. The RHLR includes data of subscribers who are logged into mobile radio networks which can be reached from the network of the calling subscriber and connected via roaming agreement.

Description

The present procedure concerns the mediation of conversations between Mobile networks from different network operators. By optimizing the technical Processes can save costs for customers and improve call quality become.

State of the art

Arranging calls between two at the same network operator Registered mobile customers (A & B subscribers) are generally made via the network of the network operator (home PLMN of the B subscriber).

If the calling subscriber (A subscriber) is outside the network of his network operator - in the area of another network - roaming agreements ensure that he can reach another customer in the network of his network operator (B subscriber). To do this, he must dial into the network of his network operator (see Fig. 1).

If the called subscriber (B subscriber) is outside the network of his network operator, his network operator ensures that the call is forwarded accordingly (see FIG. 2).

Even if A and B subscribers are outside the home network, the call is connected via the Home PLMN. This also applies if the PLMN in which A and B subscribers are currently logged in is identical (see FIG. 3).

Criticism of the state of the art

It is always necessary that the calls are made via the network operator to which the B-participant is contractually bound, even if the physical through circuit does not necessarily require the radio resources of this network operator.  

Especially due to the emerging tri-band devices and the resulting ones largely global usability of a mobile terminal can increase this Effort and thus lead to increased costs. If a customer currently in the Network of another network operator is located, from the network of a third network operator to be called out, a phone number with the B subscriber contractually bound network operator can be called. The resulting Costs are passed on to the customer and make the use of roaming Possibility very unattractive.

With the method according to the invention, it is no longer necessary for the B subscriber to call via the network to which the B subscriber is contractually bound. So you can Costs for cumbersome routes (e.g. USA-Germany-USA) are eliminated and this price advantage can be passed on to the customer. Reduce further the time delays caused by the transmission are considerable, which is a significant improvement in the quality of the conversation means.

technical description

The network operator (e.g. T-Mobil) can also be found in the countries (e.g. USA) Assign a phone number (eg "T-USA") in which he does not have his own network. On Calling customer (A subscriber) thus has the option of reaching the destination in several ways To reach (B-participant). Provided the A-subscriber has the cheapest access to the network operator of the B subscriber, both can save considerable costs. A T-Mobil customer in the US can have another T-Mobil customer who is also a customer located in the United States, call directly through United States "T-USA" -B subscribers. The price for USA-Germany-USA are therefore not applicable.

The prerequisite for this is that the A subscriber in a network of network operator A has a Has residence permit. The A-subscriber can therefore be a customer of the network operator A, or he can be a customer of another network operator who works with network operator A has a roaming agreement.  

The network of network operator A is abbreviated PLMN A, that of Network operator B with Home PLMN B. It is also assumed that the B subscriber Home PLMN B customer, and that Home PLMN B with both PLMN A and roaming with the network operator of the PLMN visited by the B subscriber Has deal. Home PLMN C is another network of network operator B, which is different from Home PLMN B either differs in the mobile radio standard used or differs in another country. Network operator B can also work in the consortium with Home Be PLMN C.

If the A-subscriber calls the B-subscriber, then without considering the invention the call to a gateway exchange based on the dialed number location (gateway MSC) managed by Home PLMN B. This gateway MSC asks the HLR of the B participant according to their whereabouts. With the address of the VLR the Connection establishment continued.

The procedure is modified by introducing an additional Remote Home Location Register (RHLR), the

• - only contains the data of the participants that are assigned to Home PLMN B or Home PLMN C be led; keeping the phone number that is for the Subscriber is fixed in his home network;
• - Associated with the PLMN A network in the form that the call is not as usual is routed to a gateway MSC in the home network of the called subscriber, but reaches the selected subscriber in the network in which he is currently stops.

RHLR does not represent its own participants, only the Home participants PLMN B or Home PLMN C. The data from RHLR and the HLRs in the networks of the Operator / consortium B or C are constantly updated.

How the association of RHLR with PLMN A can be technically realized depends essentially on how the roaming agreements between different network operators can be adapted to the new situation. The following variants are considered for the technical solution:

• 1. The RHLR is integrated into the PLMN A in such a way that some or all of the calls to subscribers from Home PLMN B are routed via the RHLR. The RHLR also has a connection to Home PLMN B so that the subscriber data can be updated continuously. This variant is shown in FIG. 4 "Direct connection of the RHLR to the PLMN A".
  If a call to a subscriber from Home PLMN B is to be set up, an MSC of PLMN A directly addresses the RHLR [ FIG. 4 (1)]. For this purpose, the same protocols [Mobile Application Part (MAP) via Transactions Capabilities Application Part (TCAP)] are used as for a request to an HLR of the PLMN A. With the help of the subscriber data received from the RHLR, the connection can be established using the signaling protocol Switching (ISDN user part) to subscriber B are continued [ Fig. 4 (2)].
  The RHLR thus appears as an HLR of the PLMN A, although it manages subscriber data from Home PLMN B and / or Home PLMN C. Appropriate agreements must be made with the network operator of the PLMN A to enable such connection.
• 2. A switching computer (remote switch) is integrated together with the RHLR like a terminal in the PLMN A, see FIG. 5 "Connection of RHLR and remote switch as terminal".
  Depending on the configuration, some or all of the calls lead to subscribers in Home PLMN B via this switching computer [ FIG. 5 (1)]. The switching computer asks the RHLR for the location of the B subscriber [ Fig. 5 (2)]. The location and other participant data are constantly updated with the help of a connection to the Home PLMN B. The switching computer then initiates a connection to the gateway MSC of the network in which the B subscriber is currently located [ FIG. 5 (3)]. If the connection establishment is successful, the switching computer connects the connection between the A subscriber and the B subscriber. The special feature of Remote Switch together with RHLR, which is the actual goal for the connection establishment, is that the RHLR is requested via a network access protocol to establish a further connection, for which a signaling protocol between switching centers is used.
  This configuration has the decisive advantage that it is less dependent on the accommodation of the PLMN A network operator. It is sufficient to subscribe to a service that forwards all calls with + country code mobile operator code or + mobile operator code to a specific end device - the switching computer with RHLR. If this is also not possible, you can subscribe to a value-added service (such as shared cost or premium rate) that performs the necessary call number translation.

Reference list

• 1. PLMN Public Land Mobile Network
• 2. MSC Mobile Switching Center
• 3. GMSC Gateway-MSC
• 4. HLR Home Location Register
• 5. RHLR Remote Home Location Register
• 6. VLR Visitor Location Register
• 7. GSM Global System of Mobile Communications
• 8. MAP Mobile Application Part
• 9. MT Mobile Termination
• 10. PSTN Public Switched Telephone Network
• 11. TCAP Transactions Capabilities Application Part
• 12. ISUP Integrated Services Digital Network User Part

Roaming

Performance feature of cellular radio networks, the availability of activated mobil stations independent of location in all radio cells in the entire coverage area of a network; In addition, roaming can also be of the same type Networks from different network operators, such as international roaming in pan-European and American GSM system.

Gateway MSC

GMSC is responsible for the connection to and from external networks. In particular takes over the GMSC for Mobile Terminated (MT) processes like MT Call (MTC), Data transmission service or short message service the route control from the external network to the current VLR of the subscriber searched for.

The gateway functions are usually housed in certain MSCs. The Selection of which of the MSC's in the GSM PLMN as access mobile switching centers can be used by the network operator. It can happen in all MSC'S GMSC functions will be implemented.

Claims (4)

1. A method for optimizing roaming in mobile radio networks, in particular for switching through calls to or from subscribers who have logged into other than the contractually bound network at the time of the connection establishment, characterized in that

• - that calls can be switched through to or from subscribers with a stay in a mobile network other than the contractually bound mobile network without the connection having to be made via the contractually bound network of the called subscriber,
• - that an additional remote home location register is integrated into the network in which the calling subscriber is located,
• that this remote home location register contains the data of subscribers who have logged into mobile radio networks, who can be reached from the network of the calling subscriber and are connected to this via roaming agreements,
• that the subscriber data in the remote home location register is updated continuously by a connection to the home location register of the home network or at the time of a connection request,
• - That with the help of the data from the remote home location register the connection to the called subscriber can be established by directly making the transition from the network of the calling subscriber to the network in which the called subscriber is currently located, and
• - That the remote home location register is always addressed if the calling subscriber dials a special code before the subscriber call number, so that the calling subscriber decides that the connection is established via the cost-effective route, and the inexpensive connection route as well is always set up if the network operator code of the home network is selected as the area code.

2. The method according to claim 1, characterized in that the remote home Location register is supplemented by a switching computer that this Combination can be reached like a terminal via the network of the calling subscriber is and is always addressed when the caller has a special code or the network operator code of the home network is selected as the area code, and that the switching computer then establishes the connection on the basis of the Participant data from the remote home location register to the called Participant initiates the conversation and if the connection is established successfully switches through. 3. The method according to claim 1, characterized in that the subscriber data are not saved in an additional remote home location register, but that there is a home location register in that of the calling subscriber used mobile network is used. 4. The method according to claim 1 to 3, characterized in that the data for the Call accounting with cost-saving routing can be recorded separately can.