METHOD AND SYSTEM FOR TRANSMITTING MESSAGE WAITING NOTIFICATION BETWEEN GSM AND TDMA NETWORKS
RELATED APPLICATIONS This application claims priority from and incorporates herein by reference the entire disclosure of U.S. Patent Application Serial No. 60/124,918, filed March 17, 1999.
BACKGROUND OF THE INVENTION Technical Field of the Invention
The present invention relates to message waiting notification messages, and more particularly, to a method for transmitting message waiting notification messa ges between differing technology networks, such as GSM and TDMA networks. Description of Related Art Within cellular networks, a mobile subscriber may roam between service areas of different networks. Various techniques have been developed to enable a mobile subscriber to continue being provided with mobile telephone services once they have left their home service area. In a first alternative, once a mobile subscriber travels i nto a new mobile switching center (MSC) coverage area and turns on their mobile station for the first time, the mobile station attempts to register with the servicing MSC for the area by transmitting an associated identification number known as the international mobile subscriber identity (IMSI) number or mobile identification number (MIN). The serving MSC communicates with the home location register associated with the mobile station using the received IMSI/MIN. This communication is to inform the HLR of the mobile station's new location and to receive requisite subscriber information from the HLR necessary to provide mobile services to the newly registering mobile station.
However, when mobile subscribers move between networks utilizing different technologies, for example, a GSM system utilizing a GSM MAP protocol and a TDMA system using a ANSI-41 protocol, the various information required to be
transmitted between the networks creates problems in converting information bet w een the protocols useable by each system.
One problem arises with subscribers that roam between networks due to the inability of message waiting notifications to be readily transferable between GSM technologies and TDMA ANSI-41 technologies. This problem arises because of the different ways in which these systems process and provide message waiting notification. There presently exists no way to provide a message waiting notificat i on to a subscriber which has left their home network and roamed into a different technology network. In the case of a GSM system, the message waiting notification is provided v ιa a short message service (SMS) message between a service center and a serving MSC. In a TDMA system using ANSI-41 technology, a message waiting notification is provided as an indication from the voice mail system toward the HLR, and the H R performs a subscriber profile update towards the serving MSC VLR. As can be seen, these two protocols for processing message waiting notification are completely dissimilar and render communications between the systems relating to message waiting notifications impossible due to the incompatibility. Thus, some method for providing the message waiting notification between systems using GSM and ANS I -41 technologies would be greatly desirable.
SUMMARY OF THE INVENTION
The present invention overcomes the foregoing and other problems with a system and method for transmitting message waiting notifications between GSM and TDMA networks. A mobility gateway interconnects a GSM network with a TDMA network. Upon receipt of an SMS message containing a message waiting notificat i on from a GSM network, selected data within the SMS message relating to the message waiting notification is extracted. This extracted information is formatted into an ANSI-41 message readable by the TDMA network. The newly formatted message which also contains the message waiting notification is transmitted to the TDMA network where the message waiting notification may be received by the GSM subscriber.
If a message waiting notification in ANSI-41 format is received at the mob 111 ty gateway, selected data relevant to the message waiting notification is extracted fi om the ANSI-41 message format and this information is formatted into an SMS message for transmission within the GSM network. The SMS message is transmitted to the TDMA subscriber within the GSM network.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, reference is m ade to the following detailed description taken in conjunction with the accompany ing drawings wherein :
FIGURE 1 is a functional block diagram illustrating a mobility gatew ay including the functionality of the present invention between a GSM network and a TDMA network;
FIGURE 2 is a signaling diagram illustrating the transmission of a message waiting notification to a GSM subscriber roaming within a TDMA network;
FIGURE 3 is a signaling diagram illustrating the transmission of a message waiting notification to a TDMA subscriber roaming in a GSM network.
FIGURE 4 is a flow diagram illustrating the manner in which the message waiting notification functionality of the present invention converts from ANSI-41 to GSM format; and
FIGURE 5, is a flow diagram illustrating the conversion of amessage waiting notification from a GSM to an ANSI-41 format.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the Drawings, and more particularly to FIGURE 1 , thei c is illustrated a block diagram of a GSM network 10 utilizing a GSM MAP protocol interconnected with a TDMA network 15 using a ANSI-41 protocol through a mob 11 I ty gateway 20. The GSM network 10 enables subscribers to access telecommunications functionalities utilizing GSM technologies. The TDMA network enables mobile subscribers to access telecommunications functionalities using TDMA technologies.
The mobility gateway 20 enables mobile subscribers from the GSM netw ork 20 to roam within the TDMA network 15 and mobile subscribers from the TDMA network to roam within the GSM network 10 while maintaining access to substanti a 1 ly all of the services and functionalities provided to them within their home netw rk. While the present system is described with respect to interconnections between a
TDMA system using the ANSI-41 protocol and a GSM system utilizing a GSM AP protocol, it should be realized that the mobility gateway 20 and discussions \\ ι th respect thereto may be extended to include other mobile protocols and networks such that the described system is not limited to use between GSM and TDMA networks. As mentioned previously, one problem existing between GSM networks and
TDMA networks is the ability to transfer message waiting notifications between the GSM system's protocol and the TDMA system's ANSI-41 protocol. The mobi lity gateway 20 provides a message waiting notification functionality 25 that enables the delivery of message waiting notification messages between GSM and TDMA networks.
Referring now to FIGURE 2, there is illustrated a signaling diagram descri b ι ng the forwarding of a message waiting notification to a GSM subscriber which is roaming within the TDMA network. The GSM service center (SC) 35 receives a vo ice mail delivery 30. In response to the voice mail delivery 30, a forward mobi le termination short message invoke 40 is transmitted to the GSM SMS-GMSC 45. The
SMS-GMSC 45 transmits a send routing information for short message invoke 5ι > to the GSM HLR 55 to retrieve routing information for the GSM subscriber 90. The send routing information for short message result 60 is transmitted back to the SMS-G SC 45 which then routes a forward short message invoke 65 including the message waiting indication (MWI) to the mobility gateway 70. The mobility gateway 70 acts as a MSC with respect to the GSM network. The mobility gateway 70 further manages the location updates from a GSM subscriber roaming in a TDMA ANSI-41 netw ork in order to know where the subscriber is currently located so that the MWI
be properly directed. The message waiting notification functionality 25 within the mobility gatew ay
70 processes at 72 the forward short message invoke 65 containing the message
waiting indication in a manner, which will be more fully discussed with respect to FIGURES 4 and 5, to generate a qualification directive invoke message 75 containing the message waiting indicator. The qualification directive invoke message 75 is transmitted to the TDMA MSC/VLR 80 which forwards the message waiting indication 85 to the GSM subscriber 90. Within the TDMA system, the message waiting indicator would normally be a symbolic indication (e.g., a phone or mail icon) rather than a language based message.
After delivering the message waiting indication 85, the TDMA MSC/VLR 80 transmits a qualification directive return result message 95 back to the mobility gateway 70. With respect to the TDMA network, the mobility gateway 70 performs as a TDMA HLR. The mobility gateway 70 and message waiting notification functionality 25 processes at 96 the qualification directive return result message 95 and transmits a forward short message result 100 to the GSM SMS GMSC 45. The GMSC 45 notifies the GSM SC 35 of completion of the message waiting notification \ ιa a forward mobile term short message result 105.
Referring now to FIGURE 3, there is illustrated a signaling diagram illustrating the delivery of a message waiting notification to a TDMA subscriber in a GS network. The TDMA voice mail system 115 receives a voice mail delivery 1 10 In response thereto, the voice mail system 115 generates a message waiting indication 120 to the TDMA HLR 125. The TDMA HLR 125 transmits a qualification direct i \ e invoke message 130, including the message waiting indication (MWI), to the mobi 11 ty gateway 135. The mobility gateway 135 acts as a TDMA VLR with respect to the TDMA network.
The message waiting notification functionality 25 within the mobility gate w ay 135 processes at 136 the qualification directive invoke message 130, as will be mot e fully discussed in a moment, and generates a qualification directive return result message 140 back to the TDMA HLR 135. A forward short message invoke message 145 is also transmitted from the mobility gateway 135 to the GSM MSC/VLR 1 50. The MSC/VLR 150 performs an SMS delivery 155 containing the message waiting indicator to the TDMA subscriber 160. The VLR 150 then generates a forward short message result message 165 back to the mobility gateway 135. The mobility gatew ay
135 appears as an SMS-GMSC with respect to the GSM network. The mobility gateway 135 also manages the location updates from a TDMA subscriber roaming in a GSM network in order to know where the subscriber is currently located
Referring now to FIGURE 4, there is generally illustrated the process by w h ich the message waiting notification functionality 25 processes a qualification directive invoke message 130 (Fig. 3) containing a message waiting notification from a TDM A network. Initially, the qualification directive invoke message 130 is processed at step 170 to determine whether or not the subscriber to which the message is directed has the ability to receive SMS messages. Next, an SM-RP-UI parameter of an SMS message is created at step 175 from data taken from the qualification directive inv oke message 130 at step 173. The SM-RP-UI parameter is composed of a transfer protocol SMS-deliver and includes the following parameters: the message type mdicatoi (set to a value "SMS-deliver"); more messages to send parameter (set to a value ' more messages are waiting for the mobile station in this SC"), reply path parameter (set to value "TP reply path is not set in this SMS-deliver"); user data header indicator parameter (set to value "the beginning of the TP-UD field contains a header in addition to the short message"); status report indication parameter (set to value "a status i eport is not requested"); originating address parameter (the address of the mobility gateway in international format, numbeπng plan E.164 and BCD coding); protocol identifier parameter (set to value "0"); data coding scheme parameter, service centre time stamp
(created by mobility gateway), user data length parameter (indicating numbei of characters); user data parameter. All of this information is included in a genei ted SMS message. Next, the generated SMS message produced at step 175 is transmitted to the VLR/MSC within a forward short message invoke message Referring now to FIGURE 5, there is illustrated a flow chart describing how message waiting notification data is extracted from a SMS message from a GSM network by the message waiting notification functionality 25 at the mobility gateway and forwarded to a TDMA network. Upon receipt of a forward short message invoke message 65 (Fig. 2), the message waiting notification functionality 25 initially determines the location of the subscπber and whether the subscriber is active in the mobility gateway at step 200.
The necessary short message contents are extracted at step 255 from the forward short message invoke parameter SM-RP-UI. The SM-RP-UI parameter is structured according to a GSM transfer protocol SMS-deliver message including the following parameters: message type indicator, more messages to send, reply path, user data header indicator, status report indication, originating address, protocol identi fier, data coding scheme, data centre time stamp, user data length and user data. Inquiry Step 260 determines whether the message contains the message waiting indication information. If so, a check of the SMS-deliver parameters is made at step 265. If any of the checks fail, a forward short message return error message with the indication "SMS delivery failure" is transmitted to the GMSC at step 273. Otherwise, the MWI flag is set, the number of pending messages is stored and a qualification directive invoke message is created at step 275 and transmitted to the TDMA MSC/VLR at step 280 The qualification directive invoke message includes the parameters- SystemMyTypeCode, QualificationlnfoCode, ESN, MLN, and Profile II a qualification directive return error/reject is received or a timeout occurs, a Forw aid
Short Message Return Error is sent back to the gateway mobile switching center with the indication "SM delivery failure". The message waiting indication information is then restored to their original values. If an empty Qualification Directive Return Result is received, an empty forward short message result is sent back to the gateway mobi le switching center. The announcement and order indicators are then cleared, and if the number of pending messages is zero, the MWI flag is cleared.
Using the above-described system, message waiting notification messages may be seamlessly transmitted between GSM and TDMA networks such that a subsci iber roaming within either of these networks may receive its call waiting notification whether they are in their home network or a network utilizing a different technology
Although a preferred embodiment of the method and apparatus of the present invention has been illustrated in the accompanying Drawings and descπbed in the foregoing Detailed Description, it is understood that the invention is not limited to the embodiment disclosed, but is capable of numerous rearrangements, modifications, and substitutions without departing from the spirit of the invention as set forth and defined by the following claims.