WO2009146743A1 - Method and telecommunication network for sending multiple users short message - Google Patents

Abstract

It is described a method and a telecommunication network for sending a short message from a sending user equipment (109) to multiple receiving user equipments. The method comprises sending a first message to a service centre (101), wherein the first message comprises data representing destination addresses of the at least two receiving user equipments. The method further comprises sending a second message to the service centre (101), wherein the second message comprises the short message and forwarding the short message from the service centre (101) to the at least two receiving user equipments.

Description

Description

Title of the invention

Method and Telecommunication Network for Sending Multiple Users Short Message.

Field of invention

The present invention relates to the field of mobile telecom^¬ munication networks, in particular to the field of short mes^¬ sage service technology. More particularly the present inven^¬ tion relates to a method for sending a short message to mul- tiple receiving user equipments. The present invention also relates to a sending user equipment, a service centre and a telecommunication network for implementing the method for sending a short message to multiple receiving user equip^¬ ments .

Art Background

Short Message Service (SMS) is a communication protocol for interchanging short messages between mobile telephone de- vices. More generally SMS allows interchanging short messages between short message user equipments (UEs) . The user equip^¬ ment may be any type of communication end device, which is capable of connecting both with a network entity and at least one of neighboring network entities by means of a wireless transmission link. In particular the user equipment may be a cellular mobile phone, a Personal Digital Assistant (PDA) , a notebook computer and/or any other movable communication device. The term Mobile Station (MS) is also commonly used as an equivalent of the term user equipment.

SMS as used on modern mobile telephones was originally de^¬ fined as a part of the Global System for Mobile communica^¬ tions (GSM) series of standards. However recently the support for the SMS includes also alternative mobile standards as well as a wide range of networks such as for example 3G net^¬ works, satellite and landline networks.

Despite of its slow initial growth the SMS developed to a massive industry. SMS derives its benefits from ubiquity and simplicity: Every modern mobile telephone can use it and there is no special address to be used to send and/or receive short messages as for example with email. SMS text messaging supports languages internationally. Also the SMS works fine with all languages supported by Unicode, including Arabic, Chinese, Japanese and Korean. Moreover, besides text, short messages can also carry binary data. Hence, it is possible to send ringtones, pictures, operator logos, wallpapers, anima- tions, business cards and WAP configurations from and to user equipments using the SMS.

A further major advantage of the SMS is that it is supported by 100% GSM mobile phones. Almost all subscription plans pro- vided by wireless carriers include an inexpensive SMS messag^¬ ing service.

One short message can comprise 140 bytes or equally 1120 bits of data. Therefore one short message can comprise 160 charac- ters if a 7-bit character encoding suitable for encoding

Latin characters like English alphabets is used. If a 16-bit Unicode UCS2 character encoding for short messages using non- Latin characters like Chinese characters is used one short message can comprise 70 characters.

An extension called concatenated short message was developed to allow for text messages comprising more than 160 English characters. When sending a concatenated short message, the sending user equipment breaks down the sent message into smaller parts and sends each of them as a single short mes^¬ sage. When these short messages reach the destination, the receiving user equipment combines the received short messages back to one concatenated short message. A further application-level extension of SMS called Enhanced Messaging Service (EMS) was developed to allow for inter^¬ changing rich-media content such as pictures, animations and melodies. Also, a formatting of the text inside an EMS mes^¬ sage is changeable. For example, the message sending user can specify whether the text in the EMS message should be dis^¬ played in bold or italic, with a large font or a small font.

According to the technical specification 3GPP TS 03.40 the SMS provides a means to transfer short messages between a User Equipment (UE) and a Short Message Entity (SME) via a short message service centre hereinafter called Service Cen^¬ tre (SC) . The short message entity is defined as any entity which can send or receive short messages. The short message entity can be located for example in a fixed network, in a user equipment or in a service centre. The service centre serves as an interworking and relaying function of the message transfer between the user equipment and the short mes- sage entity.

SMS comprises Short Message Service - Point-to-Point (SMS-PP) services, which are one-to-one and/or one-to-a-few services. These services can be used between the user equipments and the service centre. Short message point-to-point services comprise two basic services: (a) Short Message Mobile Termi^¬ nated Point-to-Point (SM MT) and Short Message Mobile Origi^¬ nated Point-to-Point (SM MO) .

SM MT denotes the capability of the GSM system to transfer a short message submitted from the service centre to one user equipment and to provide information about the delivery of the short message either by a delivery report or a failure report with a specific mechanism for a later delivery.

SM MO denotes the capability of the GSM system to transfer a short message submitted from the user equipment to one short message entity via a service centre and to provide informa- tion about the receipt of the short message either by a re^¬ ception report or a failure report.

An active user equipment can submit a short message Transfer Layer Protocol Data Unit (TPDU) comprising the short message to a short message service center at any time, independently whether or not there is a speech or a data call in progress. The short message TPDU is submitted in a form of an SMS- SUBMIT message. A report in a form of either a positive or a negative acknowledgement message will always be returned to the user equipment. In the positive case the report will con^¬ firm that the service centre has received the short message TPDU. In the negative case the report will inform the user equipment that it was impossible to deliver the short message TPDU to the service centre, including the reasons why the re^¬ ception failed.

The service centre provides a store-and-forward mechanism. It attempts to send the short message to the designated receiv- ing user equipment. If the receiving user equipment is not reachable the service centre queues the short message for a later retry. The service centre supports both the mobile originated and the mobile terminated operations.

In some situations a user may wish to send a short message with an identical content to multiple receiving user equip^¬ ments. This may be of an advantage for example when the user tries to organize a meeting of at least three persons, in^¬ cluding himself. Using his user equipment the user can form the short message and choose - if provided - a corresponding option from a menu of his user equipment to enter destination addresses of the multiple receiving user equipments. After executing a submit request a short message TPDU - in the form of an SMS-SUBMIT message - comprising the short message will be sent from the user equipment to the service centre as many times as the number of the destination addresses is. This means that the same short message TPDU will be submitted from the sending user equipment to the service centre over and over, once for each destination address. Correspondingly for each submission an acknowledgement message, positive or nega^¬ tive, will be returned to the user equipment reporting on the receipt or on the failure of the short message TPDU submis- sion to the service centre. Hence, there will be also as many acknowledgement messages as the number of the destination ad^¬ dresses is.

Such a method for sending short messages to multiple user equipments is time and radio network resource consuming as the time and radio network resource consumption is directly proportional to the number of the destination addresses of the receiving user equipments. The same holds also with re^¬ spect to mobile-services switching centre resources and visi- tor location register resources. Also it can be quite annoy^¬ ing for the user to receive the multiple acknowledging mes^¬ sages from the short service centre. The same applies also to the concatenated short messages as well as to the EMS mes^¬ sages .

There may be a need for a method for sending short messages and/or their extensions like concatenated short messages and/or EMS messages to multiple user equipments which better utilizes radio network resources, mobile-services switching centre resources and visitor location register resources. Also there may be a need for a sending user equipment, a short message centre and a telecommunication network compris^¬ ing the sending user equipment and the service centre for im^¬ plementing the method for sending short messages.

Summary of the Invention

This need may be met by the subject matter according to the independent claims. Advantageous embodiments of the present invention are described by the dependent claims.

According to a first aspect of the invention there is pro^¬ vided a method for sending a short message from a sending user equipment to at least two receiving user equipments. The method comprises sending a first message to a service centre, wherein the first message comprises data representing desti^¬ nation addresses of the at least two receiving user equip- ments. The method further comprises sending a second message to the service centre, wherein the second message comprises the short message, and forwarding the short message from the service centre to the at least two receiving user equipments.

This aspect of the invention is based on the idea that the presently used method for sending short messages to multiple receiving user equipments, i.e. a Multiple Users Short Mes^¬ sage (MUSM) , can be considerably improved if the number of messages being sent from the sending user equipment to the service centre could be reduced. Such a reduced number of messages sent from the sending user equipment to the service centre can result in a better utilization of available radio network resources, mobile-services switching centre resources and visitor location register resources. Hence, a network load between network entities such as for example the service centre, a mobile-services switching centre and a visitor lo^¬ cation register can be reduced. In this respect it can be of an advantage if short message TPDU comprising the short mes^¬ sage is being sent from the sending user equipment to the service centre only once. This short message TPDU can pref^¬ erably be sent using the same format as the format used usu^¬ ally for short message TPDUs, for example the SMS-SUBMIT for^¬ mat according to technical specification 3GPP TS 03.40. The short message TPDU can be sent in any format, which is com- patible with the standards used for the SMS within the GSM and/or within Code Division Multiple Access (DCMA) and/or Digital AMPS technologies and or Personal Communication Sys^¬ tem (PCS) 1900.

To achieve the above goal the short message TPDU can be sent within a second message, preceded by another message - a first message. The first message can also be sent from the sending user equipment to the short message centre. The first message can comprise information about the multiple destina^¬ tion addresses of the receiving user equipments. Preferably the first message can be sent as a TPDU in a format which compatible with the standards used for the SMS within the GSM and/or within Code Division Multiple Access (DCMA) and/or Digital AMPS technologies. A new SMS-SUBMIT-MANY format can be defined to send the first message.

Because of the first and second message being compatible with the technical standards as they are used for the SMS, the standardized store-and-forward mechanism of the service cen^¬ tre can be easily extended to forward the short message to the multiple user equipments. If for example the SMS within the GSM is used to send the multiple users short message, the second message can be sent using the above mentioned SMS- SUBMIT message format. In order to forward the short message to the multiple receiving user equipments the service centre can form multiple messages using a TS-SUBMIT . IND format specified within 3GPP TS 03.40, i.e. the same format as used for forwarding a conventional single short message. However according to the present invention the multiple TS-SUBMIT . IND messages can be formed using the data comprised in the first and the second message in order to forward the short message to the respective multiple receiving user equipments.

Because of the second message being compatible with the tech^¬ nical standards as they are used for the SMS, the acknowl^¬ edgement message sent from the service centre to the sending user equipment and reporting on the receipt or on the failure of the second message submission to the service centre can be formed and sent in a standard manner without modifications being needed. Moreover only one acknowledgement message from the service centre to the sending user equipment reporting on the second message can be sufficient. The acknowledgement message reporting on the second message can be either posi^¬ tive or negative. An SMS-SUBMIT-REPORT format defined in 3GPP TS 03.40 can be used to form the acknowledgement message re^¬ porting on the second message. Hence, an effective and full use of the above mentioned SM MO and SM MT services of the GSM system can be achieved with respect to the second mes^¬ sage .

It can be seen as a considerable advantage of the present in^¬ vention that the method of the present invention can be com^¬ patible with the existing standards. Hence the method can be widely used on modern user equipments while maintaining all the above mentioned advantages of the SMS.

The term short message can refer to the short message as be^¬ ing used within the SMS as well as to its possible extensions for example a concatenated short message and/or an EMS mes^¬ sage .

According to a further embodiment of the invention the data representing destination addresses of the at least two re^¬ ceiving user equipments comprises individual destination ad^¬ dresses of the at least two receiving user equipments.

Using the individual destination addresses as the data repre^¬ senting destination addresses of multiple receiving user equipments within the first message means that no special ad^¬ dresses need to be used to send a multiple users short mes- sage. Hence, one of the main advantages of the SMS can be maintained. Further, because of using the individual destina^¬ tion addresses for sending a multiple users short message the compatibility of the method of the present invention with the above mentioned existing technical standards can be easily achieved. The service centre can store the individual desti^¬ nation addresses to which the short message should be for^¬ warded. The messages formed by the service centre in order to forward the short message to multiple receiving user equip^¬ ment can be formed with use of the data comprised in the first message and in the second message. For example, to for^¬ ward the short message to the multiple receiving user equip^¬ ments the service centre can form multiple messages using a TS-SUBMIT. IND format specified within 3GPP TS 03.40, i.e. the same format as used for forwarding a conventional single short message. These multiple TS-SUBMIT . IND messages can be formed using - among other data comprised in the first mes^¬ sage and in the second message - also the individual destina- tion addresses of multiple user equipments comprised the first message and the short message comprised in the second message .

According to a further embodiment of the invention the method comprises sending an acknowledgement message from the service centre to the sending user equipment acknowledging a receipt of the first message.

With this embodiment the SM MO service capability of the GMS system can be extended in order apply also to the first mes^¬ sage. The extension concerns the capability of the GSM system to transfer the first message from the sending user equipment to the service centre and to provide information about the receipt of the first message either by a reception report or a failure report. This capability is not a part of the status report capabilities described in section 3.2.9 of 3GPP TS 03.40. For a reliable implementation of the method of the present invention it can be of an advantage to a have such an extension of the SM MO capability available. The acknowledge- ment message can be a positive one in the case of the recep^¬ tion report or a negative one in the case of the failure re^¬ port. A new type of message, an SMS-SUBMIT-MANY-REPORT TPDU can be defined to report on the first message. The SMS- SUBMIT-MANY-REPORT TPDU can be carried as a Reply Path-User- Data (RP-User-Data) within an RP-ERROR RPDU defined in 3GPP

TS 04.11 and can be a part of the negative acknowledgement to the first message, if the SMS-SUBMIT-MANY format is used for the first message. The SMS-SUBMIT-MANY-REPORT TPDU can be also carried as the Reply Path-RP-User-Data within an RP-ACK RPDU defined in 3GPP TS 04.11 and can be a part of the posi^¬ tive acknowledgement to the first message, if the SMS-SUBMIT- MANY format is used for the first message. In the case of an positive acknowledgement there can be only one acknowledge^¬ ment message sent from the SC to the sending UE.

According to a further embodiment of the invention the data representing destination addresses of at least two receiving user equipments comprises a destination count parameter indi^¬ cating the number of destination addresses of the at least two receiving user equipments.

The destination count parameter comprised in the first mes^¬ sage can represent important information with respect to the method of the present invention. The value of the destination count parameter can be an integer number. For example, based on the destination count parameter the mobile-services switching centre and/or the service centre can detect that a short message is being sent to multiple receiving user equip^¬ ments .

Also depending for example on the format used for the first message TPDU there can be a restriction on the number of mul^¬ tiple receiving user equipments to which the short message can be sent. In this case the destination count parameter can provide for a check whether the number of the destination addresses has not been exceeded.

According to a further embodiment of the invention the method further comprises checking a plausibility of the destination count parameter and inserting a result of the plausibility check of the destination count parameter into the acknowledg- ing message.

A non-plausibility of the destination count parameter can be for instance caused by invalid information being included in the destination count parameter. An invalidity of the infor- mation included in the destination count parameter can for example cause that the mobile-services switching centre can fail to detect that a short message is being sent to multiple receiving user equipments. Further the invalid information included in the destination count parameter can indicate that the number of the destination addresses has been exceeded in case when there is a restriction put on number of the multi^¬ ple receiving user equipments to which the short message can be sent. Therefore it can be advantageous to have the plausi^¬ bility and/or validity check of the destination count parame^¬ ter implemented within the method of the present invention. A non-plausible destination count parameter can be indicated in the negative acknowledgement message by a corresponding TP- Failure-Cause (TP-FCS) value using the hexadecimal coding, if the SMS within GMS is used, for example the non-plausible destination count parameter can be indicated by the hexadeci^¬ mal value C8.

According to a further embodiment of the invention the method further comprises checking a plausibility of the first mes^¬ sage by the service centre and inserting a result of the plausibility check of the first message into the acknowledge^¬ ment message.

The acknowledge message can be either a positive or a nega^¬ tive message. A positive acknowledge message reports on the receipt of the first message to the service centre. The first message can be delivered to the service centre if is plausi- ble, i.e. there is no reason why the first message can not be transferred and/or processed. The plausibility of the first message can be of an importance for the method of the present invention being reliable. A negative acknowledgement message reports on a failure of transferring and/or processing of the first message. There can be many reasons why the transfer and/or processing of the first message can fail. These rea^¬ sons are included and marked as mobile originated in sub- clause 9.2.3.22 of 3GPP TS 03.40 in a TP-Failure Cause (TP- FCS) table together with the corresponding hexadecimal TP-FCS value being inserted in the negative acknowledgement message. In case of the present invention this table can be extended by adding the above mentioned new hexadecimal TP-FCS value, e.g. C8 for the case of a non-plausible destination count pa^¬ rameter, and a corresponding mark in the MO column.

According to a further embodiment of the invention in case of a negative plausibility check of the first message the result of the plausibility check of the first message comprises a destination count value indicating a non-plausible destina^¬ tion address within the first message.

One of the reasons for the failure of the transfer and/or processing of the first message can be for example an inva^¬ lidity of one or more destination addresses comprised in the first message. However also other reasons included and marked as mobile originated in subclause 9.2.3.22 of 3GPP TS 03.40 in a TP-Failure Cause (TP-FCS) table can cause that a desti^¬ nation address in not-plausible. The destination addresses send in the first message can be represented by corresponding destination count values, depending for example on the order in which the destination addresses have been inserted in the first message TPDU. In the case that one or more destination addresses are invalid, the corresponding destination count values can be inserted in the corresponding negative acknowl^¬ edgement messages. For each non-plausible destination address there can be one negative acknowledgement message reporting on it. The sending user equipment can recognize the invalid destination addresses from the corresponding destination values after the receipt of the acknowledgement message. Using destination count values instead of full destination ad^¬ dresses can help to a better utilization of the radio network resources, mobile-services switching centre resources and visitor location register resources. Hence, the network load between network entities such as for example the service cen^¬ tre, a mobile-services switching centre and a visitor loca^¬ tion register can be reduced.

According to a further embodiment of the invention in case of a negative plausibility check of the first message the result of the plausibility check of the first message comprises a reason for which the plausibility check of the first message failed.

Besides having the destination count values indicating non- plausible destination addresses within the first message re^¬ ported in the negative acknowledgement messages it can be useful to know reasons why the first message was not plausi^¬ ble, i.e. why the transfer and/or processing of the first message failed. Knowing the reason a new plausible first mes- sage can be sent, with the failure reason being eliminated if possible. The possible failure reasons are included in sec^¬ tion 9.2.3.22 of 3GPP TS 03.40. These failure reasons are marked in the MO column of the TP-Failure Cause (TP-FCS) ta^¬ ble, in which table the failure reasons are indicated also together with the corresponding hexadecimal TP-FCS value inserted in the corresponding negative acknowledgement message. In case of the present invention this table can be extended by adding as mentioned above the new hexadecimal TP-FCS value, e.g. C8, for the case of a non-plausible destination count parameter.

According to a further embodiment of the invention the short message is sent to at most ten receiving user equipments.

It can be of an advantage that the method of the present in^¬ vention can be compatible with the existing technical standards used for the SMS. This can be achieved when the number of receiving user equipments to which the short message is being sent does not exceed ten user equipments. For example, when the first message TPDU is sent in a format compatible with the standards used for the SMS within the GSM, the newly defined SMS-SUBMIT-MANY format can be used. In this case ba^¬ sic elements used for the SMS-SUBMIT-MANY format can comprise some of the basic elements used for the SMS-SUBMIT format, which SMS-SUBMIT format is defined in 3GPP TS 03.40 and also can be used to form the second message. Hence a layout of the fist message TPDU can be made compatible with a layout of the SMS-SUBMIT message. According to a further aspect of the invention there is pro^¬ vided a sending user equipment for sending a short message to at least two receiving user equipments. The sending user equipment comprises a first unit for sending a first message to a service centre, wherein the first message comprises data representing destination addresses of the at least two re^¬ ceiving user equipments. The sending user equipment further comprises a second unit for sending a second message compris- ing the short message to the service centre, wherein the sec^¬ ond message is adapted to initiate a forwarding of the short message to the at least two receiving user equipments by the service centre.

Also this aspect of the present invention is based on the idea that sending a multiple users short message, i.e. a short message to multiple receiving user equipments, can be made more effective by reducing the number of messages being sent from the sending user equipment to the service centre. Such a reduced number of messages sent from the sending user equipment to the service centre can result in a better utili^¬ zation of available radio resources, mobile-services switch^¬ ing centre resources and visitor location register resources. Hence, the network load between network entities such as for example the service centre, a mobile-services switching cen^¬ tre and a visitor location register can be reduced. Hence, it can be of an advantage to provide for a sending user equip^¬ ment capable to send a message TPDU, which message TPDU com^¬ prises the short message to be forwarded to multiple receiv- ing user equipments, only once. This goal can be achieved by means of the first unit and the second unit of the sending user equipment as described by the above mentioned aspect of the present invention.

The second message can be sent using the same format as the format used usually for short message TPDUs, for example the SMS-SUBMIT format according to technical specification 3GPP TS 03.40 or in any other format, which is compatible with the standards used for the SMS within the GSM and/or within Code Division Multiple Access (DCMA) and/or Digital AMPS technolo^¬ gies. Hence the second unit of the sending user equipment can be identical with a unit for sending short messages to single users. Therefore the second message can easily be adapted to initiate a forwarding of the short message to the multiple receiving user equipments by the service centre.

Also the first message can be sent as a TPDU in a format which is compatible with the standards used for the SMS within the GSM and/or within Code Division Multiple Access (DCMA) and/or Digital AMPS technologies. Hence the function^¬ alities of first unit and the second unit could be realized by one single unit.

Hence the sending user equipment according to this aspect of the present invention can be used for an effective implementation of the method for sending a multiple users short mes^¬ sage according to the present invention.

According to a further aspect of the invention there is pro^¬ vided a service centre for sending a short message from a sending user equipment to at least two receiving user equip^¬ ments. The service centre comprises a first unit for receiv- ing a first message from the sending user equipment, wherein the first message comprises data representing destination ad^¬ dresses of the at least two receiving user equipment. The service centre further comprises a second unit for receiving a second message from the sending user equipment, wherein the second message comprises the short message. The service cen^¬ tre also comprises a third unit for forwarding the short mes^¬ sage to the at least two receiving user equipments.

Also this aspect of the present invention is based on the idea that sending a multiple users short message, i.e. a short message to multiple receiving user equipments, can be made more effective by reducing the number of messages being received by the service centre from the sending user equip- ment . Such a reduced number of messages received by the ser^¬ vice centre from the sending user equipment can result in a better utilization of available radio network resources, mo^¬ bile-services switching centre resources and visitor location register resources. The network load between network entities such as for example the service centre, a mobile-services switching centre and a visitor location register can be reduced. Hence, it can be of an advantage to provide for a ser^¬ vice centre capable to receive a message TPDU, which message TPDU comprises the short message to be forwarded to multiple receiving user equipments, only once. This goal can be achieved by means of the first unit, the second unit and the third unit as described by the above mentioned aspect of the present invention.

The second message can be sent by the sending user equipment using the same format as the format used usually for short message TPDUs, for example the SMS-SUBMIT format according to technical specification 3GPP TS 03.40 or in any other format, which is compatible with the standards used for the SMS within the GSM and/or within Code Division Multiple Access (CDMA) and/or Digital AMPS technologies. Hence the second unit and the third unit of the service centre can be identi^¬ cal with a unit for sending conventional short messages to single users.

Also the first message can be sent by the sending user equip^¬ ments as a TPDU in a format which is compatible with the standards used for the SMS within the GSM and/or within Code Division Multiple Access (DCMA) and/or Digital AMPS technolo^¬ gies. Hence the functionalities of first unit, the second unit and the third unit could be realized by one single unit.

Hence, the service centre according to this aspect of the present invention can be used for an effective implementation of the method for sending a multiple users short message of the present invention. According to a further aspect of the invention there is pro^¬ vided telecommunication network comprising a sending user equipment and a service centre according to the above de^¬ scribed aspects of the present invention.

The telecommunication network can also comprise a mobile- services switching centre adapted to detect the first and the second message sent from the sending user equipment to the service centre. The mobile-services switching centre can be an exchange entity which performs switching functions for user equipments located in a geographical area, to which the sending user equipment belongs.

The telecommunication network according to this aspect of the present invention can be employed to implement the method for sending short messages and/or their extensions like concate^¬ nated short messages and/or EMS messages to multiple user equipments according the present invention in order to better utilize radio network resources, mobile-services switching centre resources and visitor location register resources. Hence, the network load between network entities such as for example the service centre, the mobile-services switching centre and a visitor location register can be reduced.

According to a further aspect of the invention there is pro^¬ vided a computer program element for controlling the telecommunication network of the present invention. The computer program element, when being executed by a data processor of the sending user equipment and/or of the service centre, is adapted for implementing the method of the present invention.

The computer program element may be implemented as computer readable instruction code in any suitable programming language such as, for example, JAVA, C++. The instruction code is operable to program a computer or other programmable de^¬ vice to carry out the intended functions. According to a further aspect of the invention there is pro^¬ vided a computer-readable medium for storing the computer program element for controlling the telecommunication network of the present invention.

The computer program element may be stored on a computer- readable medium such as for example a removable disk, a vola^¬ tile or non-volatile memory, or an embedded memory/processor. The computer program element may also be available from a network, such as the WorldWideWeb, from which it may be downloaded.

The invention may be realized by means of a computer program element respectively software. However, the invention may also be realized by means of one ore more specific electronic circuits respectively hardware. Furthermore, the invention may also be realized in a hybrid form, i.e. in a combination of software modules and hardware modules.

In the following there will be described exemplary embodi^¬ ments of the present invention with reference to a method for sending a short message from a sending user equipment to at least two receiving user equipments. It has to be pointed out that of course any combination of features relating to dif- ferent subject matters is also possible.

It has to be noted that embodiments of the invention have been described with reference to different subject matters. In particular, some embodiments have been described with ref- erence to method type claims whereas other embodiments have been described with reference to apparatus type claims. How^¬ ever, a person skilled in the art will gather from the above and the following description that, unless other notified, in addition to any combination of features belonging to one type of subject matter also any combination between features relating to different subject matters, in particular between features of the method type claims and features of the appa- ratus type claims is considered as to be disclosed with this application .

The aspects defined above and further aspects of the present invention are apparent from the examples of embodiments to be described hereinafter and are explained with reference to the examples of embodiments. The invention will be described in more detail hereinafter with reference to examples of embodi^¬ ments but to which the invention is not limited.

Before describing exemplary embodiments of the present inven^¬ tion few definitions as they will be used hereinafter are listed. To make this list self-contained also some defini^¬ tions already given above are repeated.

User Equipment (UE) : Any type of communication end device, which is capable of connecting both with a network entity and at least one of neighboring network entities by means of a wireless transmission link, for example a cellular mobile phone, a Personal Digital Assistant (PDA) , a notebook com^¬ puter and/or any other movable communication device. The term Mobile Station (MS) is also commonly used as an equivalent of the term user equipment .

Mobile-services Switching Centre (MSC) : The MSC is an ex^¬ change entity which performs switching functions for the user equipment located in a geographical area designed as an MSC area. The MSC and a Service centre can be integrated.

Service Centre (SC) : A functional entity responsible for re^¬ laying and store-and-forwarding a short message between any network entity which may send and receive short messages and the user equipment. The SC is not a part of the GSM Public Land Mobile Network (PLMN) , however MSC and SC can be inte- grated. Short message entity (SME) : An entity which may send and re^¬ ceive short messages. The SME can be located in a fixed net^¬ work, and UE, or an SC.

Home Location Register (HLR) : A central database that con^¬ tains data of each mobile phone subscriber that is authorized to use the GSM core network. The stored subscriber data can comprise for example a location information, a directory number such as for example the Mobile Station ISDN number (MSISDN) , a radio numbering plan identification such as for example the International Mobile Subscriber Identity (IMSI), supplementary service profiles, teleservice profiles, etc.

Visitor Location Register (VLR) : A database which stores in- formation about all the user equipments that are currently under the jurisdiction of the MSC which it serves. From all the information it stores about each UE, the most important is the current

jty (LAI) . LAI identifies under which jase ct_^;,_on Con;.rollcr (BSC) the UE is currently present. Whenever an MSC detects a new UE in its network, in addition to creating a new record in the VLR, it also updates the HLR of the mobile phone subscriber.

Visited MSC (VMSC) : The MSC where a customer is currently lo- cated.

Serving GPRS Support Node (SGSN) : An exchange entity which performs switching functions for mobile stations located in a geographical area designed as the SGSN area.

Gateway MSC for SMS (SMS-GMSC) : A functional entity of an MSC capable of receiving a short message within a PLMN from an SC, interrogating the corresponding HLR for routing information and SMS information, and delivering the short message to a VMSC or SGSN of an receiving user equipment.

SMS Interworking Mobile Switching Centre (SMS-IWMSC) : A func^¬ tional entity of an MSC capable of receiving a short message from within a PLMN and submitting it to a recipient service centre .

Brief Description of the Drawings

Figure 1 shows a basic set of network entities involved in a conventional short message service as well as interfaces be^¬ tween these entities.

Figure 2 shows basic call flow for a conventional short mes^¬ sage mobile originated service.

Figures 3A to 3D show four different phases of transferring and processing a first message between a sending user equip^¬ ment and a service centre.

Figures 4A to 4D show four different phases of transferring and processing a second message between a sending user equip- ment and a service centre.

Figures 5A to 5D show four different phases of transferring and processing an acknowledgement message between a service centre and a sending user equipment, the acknowledgement mes- sage reporting of thr first message.

Figure 6A shows a table of basic elements of an SMS-SUBMIT- MANY message.

Figure 6B shows a layout of an SMS-SUBMIT-MANY message.

Figure 7A shows a table of basic elements of an SMS-SUBMIT- MANY-REPORT for an RP-ERROR message.

Figure 7B shows a layout of an SMS-SUBMIT-MANY-REPORT for an RP-ERROR message . Figure 8 shows a row added to the TP-Failure Cause (TP-FCS) table from subclause 9.2.3.22 of the technical specification 3GPP TS 03.40

Detailed Description

The illustrations in the drawings are schematic. It is noted that in different figures, similar or identical elements are provided with reference signs, which are different from the corresponding reference signs only within the first digit. Digits in parenthesis if these accompany descriptions of mes^¬ sages in figures 3A-3D, 4A-4D and 5A-5D refer to correspond^¬ ing technical specifications of 3GPP TS. Messages in these Figures not accompanied by digits in parenthesis are speci^¬ fied in 3GPP TS 03.40.

Figure 1 shows a basic set of network entities involved in a conventional short message service as well as interfaces be- tween these network entities, however a similar basic set of properly adapted network entities can be used in order to implement the method for sending a short message from a sending user equipment to at least two receiving user equipments ac^¬ cording to the present invention.

GSM mobile telephone system presently uses Short Message Ser^¬ vice (SMS) for sending short messages to and from user equip^¬ ments (UEs) . To perform the SMS, a basic set of GSM Public Land Mobile Network (PLMN) entities can be used. The basic set of entities comprises in addition to a User Equipment

(UE) 109 a Mobile-services Switching Centre (MSC) 107, a

Visitor Location Register (VLR) 111, a Home Location Register

(HLR) 105, and an entity comprising a Gateway MSC for Short

Message Service and an SMS Interworking Mobile Switching Cen- tre (SMS-GMSC/SMS-IWMSC) 103. Another network entity that is not part of the GSM PLMN but can also be used for carrying out the SMS is a service centre (SC) 101. However MSC 107 and SC 101 could also be integrated in one network entity. The SC 101 is connected to the SMS-GMSC/SMS-IWMSC 103 by an interface 102. The SMS-GMSC/SMS-IWMSC 103 is connected to the MSC 107 via an interface 106. The HLR 105 is connected to the SMS-GMSC/SMS-IWMSC 103 by an interface 104. The VLR 111 is connected to the MSC 107 by an interface 110 and The UE 109 is connected to the MSC 107 by an interface 108. The SC 101 stores and forwards short messages over the interface 102, which interface may be represented bythe protocol interface described in 3GPP TS 03.40. The SMS-GMSC/SMS-IWMSC 103 serves as a port into the PLMN. The SMS-GMSC and the SMS-IWMSC can form separate entities but they also can be integrated in one GMSC/IWMSC 103 entity as illustrated in Fig. 1.

The VLR 111 controls service areas when the UE 109 roams within one PLMN or between different PLMNs. In other words, at one specific time, the US 109 is roaming within one spe^¬ cific service area of the VLR 111. The VLR 111 also can be described as a "copy" of the subscriber's HLR 105. For exam- pie, when registering a present location of the UE 109 by sending a location update to the HLR 105, subscriber data stored in the HLR 105 are transferred to the VLR 111. The VLR 111 contains data that is needed to establish calls and sig^¬ nal transactions towards the user equipment 109. The MSC 107 performs calls and transaction control by interworking with the VLR 111. The MSC 107 is responsible for switching func^¬ tions and controlling hardware when establishing a call or a signal connection. In particular, the MSC 107 cooperates with the VLR 111 wherein subscriber data for the call in question are stored. The interfaces 104, 106 and 110 are performed by a Mobile Application Part (MAP) which is a signaling protocol used for roaming and handover signaling in GSM. The MSC also interfaces the radio network via a base station controller

(BSC) , not shown .

Figure 2 shows basic call flow for a conventional short mes^¬ sage mobile originated service. The call flow of a conventional short message for SM MO starts by sending a mobile originated short message from the UE 209 over the corresponding interface to the MSC 207 in a step S201. The mobile originated short message is specified in 3GPP TS 04.11. The mobile originated short message com^¬ prises a short message which is to be delivered to a receiv^¬ ing user equipment. The receiving user equipment is identi^¬ fied by its MSISDN number in the mobile originated short mes^¬ sage. The MSC 207 interrogates the VLR 211 for a routing in- formation using a MAP message "MAP_SEND_INFO_FOR_MO_SMS" in a step S202. The VLR 211 acknowledges the routing information with a MAP message "MAP_SEND_INFO_FOR_MO_SMS_ACK" in a step S203. After the MSC 207 has received the information to route the short message to the concerned SMS-IWMSC 203, the MSC forwards the short message to the SMS-IWMSC 203 using a MAP message "MAP_MO_FORWARD_SHORT_MESSAGE" in a step S204. The SMS-IWMSC 203 in turn forwards - as specified in 3GPP TS 03.40 - the short message to the SC 201 in a step S205. A short message acknowledgement is sent - as specified in 3GPP TS 03.40 - from the SC 201 to the SMS-IWMSC 203 in a step S206. After receiving the short message acknowledgement from the SC 201 the SMS-IWMSC 203 sends in a step S207 the short message acknowledgment to the MSC 207 through a MAP message "MAP_MO_FORWARD_SHORT_MESSAGE_ACK". The short message ac- knowledgement is delivered - as specified in 3GPP TS 03.40 - from MSC 207 to the UE 209 in a step S208.

Details of the call flow for the conventional short message mobile originated service are specified in Annexure C of 3GPP TS 03.40. The MAP messages sent in steps S202-S204 and S207 are defined in 3GPP TS 09.02.

Figures 3A to 3D show four different phases of transferring and processing a first message between a sending user equip- ment and a service centre.

Elements in dashed boxes are optional. Abbreviations used in Figs. 3A to 3D but not explicitly explained here can be found at the end of the description. As a precaution the following should be noted: In order to keep track of messages and re^¬ ports about those messages, primitives between a Short Mes^¬ sage Application Layer (SM-AL) and a Short Message Transfer Layer (SM-TL) comprise a Short Message Identifier (SMI), which is a reference number for the message associate with the primitive. This SMI is mapped to and from a short message identifier used between the SM-TL and the Short Message Relay Layer (SM-RL) . The short message identifier is not carried between network entities and therefore a given message may have different SMIs at the UE and SC side (see also sub- clauses 9.2.1 and 9.3.1 of 3GPP TS 03.40) . The same remarks apply also to Figs. 4A to 4D and 5A to 5D described later.

The call flow of the first message between a sending UE and an MSC is illustrated in Fig. 3A. When a user initiates a SMS for sending a short message to multiple user equipments, a message in SMS-SUBMIT-MANY format is initiated over the Short Message Transfer Layer (SM-TL) from a TS-SUBMIT .REQ request on the Short Message Application Layer (SM-AL) . This initia^¬ tion lies within the scope of the UE. One of destination ad^¬ dresses of the multiple user equipments is comprised in a destination address (DA) element of TS-SUBMIT .REQ and the remaining ones are comprised in a short message (SM) element of the TS-SUBMIT. REQ. The UE collects all the destination address of the multiple user equipments and adds these in an order to the Transfer Protocol Destination Address (TP-DA) element of the SMS-SUBMIT-MANY message. The number of address added to the TP-DA as incorporated in a destination count pa- rameter within a TP-DC element of the SMS-SUBMIT-MANY message. A message reference (TP-MR) of SMS-SUBMIT-MANY is ob^¬ tained from the SMI of the TS-SUBMIT .REQ and the mapping of the SMI to the TP-MR is a local matter and responsibility of the UE. This mapping does not fall in the standard of the GSM.

A basic element structure of the TPDU SMS-SUBMIT-MANY is shown in Fig. 6A and a layout of the TPDU SMS-SUBMIT-MANY is shown in Fig. 6B. An SM-RL-DATA. REQ request as specified in 3GPP TS 04.11 is formed on the SM-TL.

A destination address (DA) of the SM-RL-DATA. REQ is taken from the service centre address (SCA) element from TS- SUBMIT. REQ. A user data (UD) of the SM-RL-DATA. REQ is updated with the SMS-SUBMIT-MANY TPDU. Thus the SM-RL-DATA. REQ is formed on the SM-TL and forwarded to a Short Message Relay Layer (SM-RL) . In the SM-RL a reply path data (RP-DATA) RPDU is formed with the SM-RL-DATA. REQ, wherein an element UDL+UD of the RP-DATA comprising user data length (UDL) and user data (UD) is formed using the UD form the SM-RL-DATA. REQ . A DA element of the RP-DATA comprises the SCA as indicated by an arrow ending in this element and the SC acronym below the box representing this element. In this step a message refer^¬ ence (MR) of the PR-DATA is obtained from the SMI in the SM- RL-DATA. REQ and the mapping of the SMI to the MR is a local matter and a responsibility of the UE. This mapping does not fall in the standard of the GSM. The RP-DATA is formed as a MNSMS-EST-REQ message to be sent to the MSC in a connection management (CM) layer.

The call flow of the first message between the MSC and an SMS-IWMSC is illustrated in Fig. 3B.

After the RP-DATA has been received by the MSC from the US on the CM layer the RP-DATA is passed to the SM-RL as an MNSMS- EST-IND message defined in 3GPP 04.11. The MNSMS-EST-IND message can be seen as an unfolded RP-DATA as it is indicated by RP-DATA in parenthesis below the MNSMS-EST-IND acronym. In this step the RP-DATA is unfolded to get the destination ad^¬ dress of the SC as indicated by the SCA acronym below a DA element of the MNSMS-EST-IND. The SCA can be put in a format according the international public telecommunication number- ing plan E.164 and sent to a VLR for getting a routing information as an MAP message SEND INFO FOR O/G CALL SETUP. MR elements of the SEND INFO FOR O/G CALL SETUP and of the MNSMS-EST-IND correspond to each other as indicted by a cor- responding arrow. After getting an SEND INFO FOR 0/G CALL SETUP ACK acknowledgement (not shown) from the VLR for rout^¬ ing the data to a corresponding SMS-IWMSC a MAP_M0_ FORWARD_SHORT_MESSAGE is formed. Operating Address (OA) ele- ments of the SEND INFO FOR 0/G CALL SETUP and of the MAP_M0_ FORWARD_SHORT_MESSAGE correspond to each other as indicted by a corresponding arrow and both comprise the MSISDN of the sending UE. The MAP_M0_ FORWARD_SHORT_MESSAGE is then enclosed into a Transaction Capabilities Application Part (TCAP) TC-BEGIN message and sent to the SMS-IWMSC on the CM layer. As has already been mentioned, based on the destina^¬ tion address DA from the MNSMS-EST-IND message, the VRL provides the MSC with the routing information as specified in 3GPP 09.02. As indicated by an arrow from COMPLETE CALL to an GMSCA element of the TCAP TC-BEGIN message a Gateway MSC Ad^¬ dress (GMSCA) , which SMSCA is included in the routing information from the VLR, is provided by the VLR. The TCAP from T7U T recommendations Q.771-Q.775 or AK^T Tl.114 is a proto^¬ col for -luiial liiα System 7 networks. A TCAP TC-BEGIN Dialog Identifier (DI) element is formed using a DI element of the SEND INFO FOR 0/G CALL SETUP. The Destination Address (DA) element of the MNSMS-EST-IND is used to form the DA element of the MAP_M0_ FORWARD_SHORT_MESSAGE. A User Data (UD) element of the TCAP TC-BEGIN is formed using an Originating Code (OC) element, the DA, the OA and a UD of the MAP_M0_ FORWARD_SHORT_MESSAGE .

The call flow of the first message between the MSC and the SC is illustrated in Fig. 3C.

After the TCAP TC-BEGIN message has been received from the MSC on the SMS-IWMSC, the Dialogue Identifier (DI) is used to identify the TCAP TC-BEGIN message on the SMS-IWMSC as indi^¬ cated by a corresponding arrow. The UD from the TCAP TC-BEGIN is extracted and the MAP_M0_ FORWARD_SHORT_MESSAGE is ob^¬ tained from the UD of the TCAP TC-BEGIN. Then an RP-DATA-MO message is formed with the MAP_M0_ FORWARD_SHORT_MESSAGE on the SM-RL and sent to the SC. A message reference MR of the RP-DATA-MO is of local significance to the IW-MSC and is not the value of the MR supplied the previously by the UE via a UE/MSC interface. Values of OA and of UD elements of the RP- DATA-MO correspond to those of the MAP_M0_ FORWARD_SHORT_MESSAGE.

Transferring and processing of the first message after the RP-DATA-MO message has been received by the SC form the SMS- IWMSC is illustrated in Fig. 3D.

The RP-DATA-MO is extracted by the SC as an RS-MO-DATA. IND message on the SM-RL. Values of OA and of SMI elements of the RS-MO-DATA. IND are obtained from values of the OA and the MR elements of the RP-DATA-MO, respectively. A UD of the RS-MO- DATA. IND is extracted from the UD of the RP-DATA-MO in order to get on the SM-TL the SMS-SUBMIT-MANY message, which has been supplied by the UE as the first message. The value of the Destination Count (DC) parameter is abstracted by the SC from the SMS-SUBMIT-MANY - as indicated by an arrow from the TP-DC element of the SMS-SUBMIT-MANY - to instruct the SC to receive the number of the destination addresses of the multi^¬ ple receiving UEs in the SMS-SUBMIT-MANY TPDU. The SMS- SUBMIT-MANY message is kept in a buffer until a second mes^¬ sage is received by the SC to process the short message com- prised in the second message and forward the short message to the multiple receiving UEs. Hence, the SC also stores the destination addresses of the multiple receiving UEs comprised in the SMS-SUBMIT-MANY message as indicated by an arrow from the TP-DA element of the SMS-SUBMIT-MANY into a circled A symbol.

Figures 4A to 4D show four different phases of transferring and processing a second message between a sending user equipment and a service centre.

The call flow of the second message between the sending UE and an MSC is illustrated in Fig. 4A. After the first message SMS-SUBMIT-MANY has been sent from the UE, the second message SMS-SUBMIT is initiated over the SM-TL from an another TS-SUBMIT .REQ request on the SM-AL. To deliver the short message to the multiple user equipments the short message is extracted from an SM element of the TS- SUBMIT. REQ and added to a TP-UD element of the SMS-SUBMIT. As a Destination Address (DA) the destination address can be used, which has been added as a last one, according to the used ordering, to the SMS-SUBMIT-MANY on the previous trans- fer. This destination address is extracted from a DA element of the TS-SUBMIT. REQ and added into a TP-DA element of the SMS-SUBMIT. An MR of the SMS-SUBMIT is obtained from an SMI of the TS-SUBMIT. REQ and the mapping of the SMI to the MR is a local matter. This mapping is a responsibility of the UE and does not fall in the standard of the GSM.

A basic element structure of the TPDU SMS-SUBMIT and a layout of the SMS-SUBMIT message are described in subclause 9.2.2.2 of 3GPP TS 03.40. An SM-RL-DATA. REQ request is formed on the SM-TL.

A destination address (DA) of the SM-RL-DATA. REQ is taken from the service centre address (SCA) element from TS- SUBMIT. REQ. A user data (UD) of the SM-RL-DATA. REQ is updated with the SMS-SUBMIT TPDU. Thus, the SM-RL-DATA. REQ is formed on the SM-TL and forwarded to a Short Message Relay Layer

(SM-RL) . In the SM-RL a reply path data RP-DATA RPDU is formed with the SM-RL-DATA. REQ, wherein an element UDL+UD of the RP-DATA comprising a user data length (UDL) and user data (UD) is formed using the UD form the SM-RL-DATA. REQ . A DA element of the RP-DATA comprises the SCA as indicated by an arrow ending in this element and the SC acronym below the box representing this element. In this step a message reference MR of PR-DATA is obtained from the SMI in the SM-RL-DATA. REQ and the mapping of the SMI to the MR is the responsibility of the UE and does not fall in the standard of the GSM. This mapping is a local matter. The RP-DATA is formed as a MNSMS- EST-REQ message to be sent to the MSC in a connection manage^¬ ment (CM) layer.

The call flow of the second message between the MSC and an SMS-IWMSC is illustrated in Fig. 4B.

For a detailed description concerning the call flow of Fig. 4B it is referred to the description passage relating to Fig. 3B.

The call flow of the second message between the SMS-IW MSC and the SC is illustrated in Fig. 4C.

For a detailed description concerning the call flow of Fig. 4C it is referred to the description passage relating to Fig. 3C.

Transferring and processing of the second message after the RP-DATA-MO message has been received by the SC form the SMS- IWMSC is illustrated in Fig. 4D.

The RP-DATA-MO is extracted by the SC as an RS-MO-DATA. IND on the SM-RL. Values of OA and of SMI elements of the RS-MO- DATA. IND are obtained from values of the OA and the MR ele- ments of the RP-DATA-MO respectively. A UD of the RS-MO- DATA. IND is extracted from the UD of the RP-DATA-MO in order to get on the SM-TL the SMS-SUBMIT message which has been supplied by the UE as the second message. The user data in the TP-UD element of the SMS-SUBMIT comprising the short mes- sage is extracted to compose multiple TS-SUBMIT . IND messages for delivering the short message to the multiple receiving user equipments. The destination addresses of the multiple receiving user equipments are taken from the previously sub^¬ mitted SMS-SUBMIT-MANY message stored by the SC. This is in- dicated by arrows starting from circled A symbols to corre^¬ sponding DA elements of the respective TS-SUBMIT . IND mes^¬ sages. The number of TS-SUBMIT . IND messages corresponds to the value of the DC parameter of the SMS-SUBMIT-MANY message, which is the first message. However for simplicity only two TS-SUBMIT. IND messages are shown of Fig. 4D. The SMS-SUBMIT- MANY and the SMS-SUBMIT are linked with the same message ref^¬ erence comprised in the MR element of the SMS-SUBMIT-MANY TPDU. The SMIs of the RS-MO-DATA. IND and of the TS-SUBMIT . IND correspond to each other. The DA element in the SMS-SUBMIT is ignored as this has already been transmitted in the SMS- SUBMIT-MANY.

Figures 5A to 5D show four different phases of transferring and processing an acknowledgement message between a service centre and a sending user equipment, the acknowledgement mes^¬ sage reporting on the first message.

The case of an SMS-SUBMIT-MANY-REPORT for an RP-ERROR message corresponding to a negative acknowledgement will be described in more detail though also the case of an RP-ACK message cor^¬ responding to a positive acknowledgement is indicated in Figs. 5A to 5D . In the case of an RP-ACK message the trans- ferring and processing of the acknowledgement message report^¬ ing of a first message is the same as in the case of an ac^¬ knowledgement message reporting on a conventional single short message, which is described in Annexure C of 3GPP TS 03 40.

The call flow of the acknowledgement message between the SC and an SMS-IW MSC is illustrated in Fig. 5A.

The Service Centre (SC) initiates the acknowledgement message SMS-SUBMIT-MANY-REPORT on the Relay Layer (SM-RL) . A table of basic elements of an SMS-SUBMIT-MANY-REPORT for an RP-ERROR message is shown in Fig. 7A and a layout of the SMS-SUBMIT- MANY_REPORT message for the RP-ERROR message is shown in the Fig. 7B. A table of basic elements of an SMS-SUBMIT-MANY- REPORT for an RP-ACK message and a layout of the SMS-SUBMIT- MANY_REPORT message for the RP-ACK message are the same as the ones described in subclause 9.2.2.2a of 3GPP TS 03 40. In the case of the RP-ERROR message the SMS-SUBMIT-MANY-REPORT comprises a TP element called Transfer Protocol Destination Count Value TP-DCV element, comprising a destination count value DCV. In this case the SMS-SUBMIT-MANY-REPORT also comprises a TP Message Type Indicator TP-MTI element and a TP Failure Cause TP-FCS element. The value of the TP-FCS parame^¬ ter indicates a possible failure reason for a first message, in the case the first message was non-plausible. In other words the TP-FCS parameter indicates a result of a plausibil^¬ ity check of the first message by the SC. The possible fail- ure reasons are included in section 9.2.3.22 of 3GPP TS 03.40 These are marked in the MO column of the TP-Failure Cause (TP-FCS) table, in which table the failure reasons are indi^¬ cated also together with the corresponding hexadecimal TP-FCS value inserted in the negative acknowledgement message. In case of the present invention this table is extended by add^¬ ing as mentioned above the new hexadecimal TP-FCS value, e.g. C8 for the case of a non-plausible destination count parame^¬ ter, and a corresponding mark in the MO column. Hence in the case of the present invention the SC is checking also for plausibility of the destination count parameter and inserting a result of the plausibility check the destination count pa^¬ rameter into the acknowledging message. The destination addresses sent in the first message can be represented, for ex^¬ ample based on their ordering within the first message, by corresponding destination count values. One of the reasons for the failure of the transfer and/or processing of the first message can be for example an invalidity of one or more destination addresses comprised in the first message. However also other reasons included and marked as mobile originated in subclause 9.2.3.22 of 3GPP TS 03.40 in a TP-Failure Cause (TP-FCS) table can cause that a destination address is not- plausible. If a destination address will be not-plausible, the TP-DCV element will comprise the count value of this des^¬ tination address and the TP-FCS element the corresponding failure reason. The SMS-SUBMIT-MANY-REPORT is integrated into the RP-ERROR within a UD element of the RP-ERROR. For each non-plausible destination address there can be one negative acknowledgement message reporting on it. Then the RPDU RP- ERROR is sent to the SMS-IW MSC.

In case of a positive acknowledgement message a message RP- ACK comprising the MR is sent to the SMS-IW MSC.

The call flow of the acknowledgement message between the SMS- IW MSC and an MSC is illustrated in Fig. 5B.

After either the RP-ACK RPDU or the RP-ERROR RPDU reaches the SMS-IW MSC it is extracted to form a TCAP message for sending it to the MSC. In the former case TCAP message can comprise a dialog identifier (DI) . In the latter case a UD element of the TCAP message comprises the UD element and a CauSe (CS) element from the RP-ERROR message. In both cases the TCAP message is sent to the MSC.

The call flow of the acknowledgement message between the SMS- MSC and the UE is illustrated in Fig. 5C.

After receiving the TCAP message by the MSC a request RPDU SM-RL-REPORT-REQ is formed using the UD and/or the DI in the TCAP on the SM-TL. The SM-RL-REPORT-REQ is then forwarded to the Relay Layer for forming a request MNSMS-DATA-REQ . In the case of the RP-ERROR message the data of failure cause ele^¬ ment TP-FCS is added to CS of the Relay Layer as indicated by the arrow starting from the SM-RL-REPORT-REQ and ending at the RP-ERROR. After the MNSMS-DATA-REQ is formed it is for^¬ warded to the Connection Management (SM-CM) layer. With the RP-ACK or RP-ERROR a control protocol data CP-DATA is formed. The RP-ACK or the RP-ERROR is inserted into the UD of the CP- DATA and sent to the UE.

Transferring and processing of the acknowledgement message after the CP-DATA has been received by the UE form the MSC is illustrated in Fig. 5D . After the CP-DATA message is received by the US from the MSC on the CM layer it is passed to the Relay Layer (SM-RL) . In case of the positive acknowledgement the RP-ACK is received by the UE. The RP-ACK comprises an MTI and an MR element. The MR value is mapped to a Short Message Identifier (SMI) of an SM-RL-REPORT-IND message. The SMI of the SM-RL-REPORT-IND message of the SM-RL is mapped to an SMI of a TS-REPORT . IND of the SM-TL. In case of the negative acknowledgement the RP- ERROR is received by the UE. The RP-ERROR of the SMS-SUBMIT- MANY-REPORT comprises MTI, MR, CS and UD elements. The MR element of the RP-ERROR is mapped to an SMI element of the SM-RL_REPORT. IND. The CS element and the UD element of the RP-ERROR are mapped to a CS element and an UD element of the SM-RL_REPORT. IND, respectively. The UD of the SM- RL_REPORT.IND is extracted to get the SMS-SUBMIT-MANY-REPORT message, which has been supplied form SC in response to the first message. The SMS-SUBMIT-MANY-REPORT message contains the TP-MTI, TP-FCS, and TP-DCV elements. The TP-FCS element of the SMS-SUBMIT-MANY-REPORT and the CS element of the RP- ERROR are mapped to a Status of Report (SoR) element of the TS-REPORT. IND. The SMI of the SM-RL-REPORT-IND is mapped to an SMI of the TS-REPORT . IND . The TP-DCV is mapped to the MSISDNs of the user equipment for which the destination ad^¬ dress has been no-plasible. This map is a local matter and is a responsibility of the UE.

The SMS-SUBMIT-MANY-REPORT is part of the negative or posi^¬ tive acknowledgement to the mobile originated first message, and is not part of the status report capabilities described in sections 3.2.9, 3.4.1 and 3.4.2 of 3GPP TS 03.40.

Figure 6A shows a table of basic elements of an SMS-SUBMIT- MANY message according to an embodiment of the present inven^¬ tion .

In this table the column pi) indicates whether the element of the SMS-SUBMIT-MANY message is mandatory (M) or optional (0) . The column p2) of this table indicates whether a parameter within the corresponding element is represented as: an inte^¬ ger (I), one bit (b) , two bits (2b), an octet (o) , seven oc^¬ tets (7o) or 2-12 octets (2-12o) .

Figure 6B shows a layout of an SMS-SUBMIT-MANY message ac^¬ cording to an embodiment of the present invention.

This layout of an SMS-SUBMIT-MANY message 600 can be compared to the layout of an SMS-SUBMIT message used for sending of a conventional single short message as shown in 3GPP TS 03.40 in subclause 9.2.2.2. In this respect it should be noted that the SMS-SUBMIT message is used within the present invention to send the second message. Parameter values included within the elements of SMS-SUBMIT-MANY are organized within octets. The octets in Fig. 6B are numbered vertically and individual bites within octets are numbered horizontally. Adjacent to the octets the parameters of the elements of the SMS-SUBMIT- MANY message 600 forming the corresponding octets are indi^¬ cated. With respect to the layout of the SMS-SUBMIT message blocks of octets corresponding to different parameters are rearranged to accommodate for the new destination count pa^¬ rameter corresponding to the TP-DC element according to the present invention and replace octets used for user data in the SMS-SUBMIT message for adding all destination addresses of the multiple receiving user equipments within the TP-DA element of the SMS-SUBMIT-MANY. According to this embodiment up to 120 octets can be used for adding the all destination addresses of the multiple receiving user equipments, which 120 octets correspond to up to ten receiving user equipments. Only the bits number 0 to 3 can be used in the TP-DA element, the remaining bits can be set to zero an ignored. The TP-DC parameter can be an integer representing the number of destination addresses of the multiple receiving user equipments sent within the SMS-SUBMIT-MANY to the SC from the sending UE. Also any other unused bits in the SMS-SUBMIT-MANY can be set to zero by a corresponding sending entity, for example the sending UE, and can be ignored by a corresponding receiving short message entity, for example by the SC. Figure 7A shows a table of basic elements of an SMS-SUBMIT- MANY-REPORT for an RP-ERROR message according to an embodiment of the present invention. Only mandatory elements TP- MTI, TP-FCS and TP-DCV of the SMS-SUBMIT-MANY-REPORT message are shown as indicated in the column pi) . The TP-MTI parame^¬ ter is represented by 2 bits and the TP-FCS and TP-DCV are represented by integers. Obligatory parameters can be for ex^¬ ample the same as specified in the subclause 9.2.2.2. a of the 3GPP TS 03.40.

Figure 7B shows a layout of an SMS-SUBMIT-MANY-REPORT for an RP-ERROR message .

The layout of an SMS-SUBMIT-MANY-REPORT for an RP-ERROR message 700 can be compared to the layout of an SMS-SUBMIT mes^¬ sage used for sending of a conventional short message as shown in 3GPP TS 03.40 in subclause 9.2.2.2a. Correspondingly to Fig. 7A only mandatory elements are considered. Parameters comprised within the elements of SMS-SUBMIT-MANY-REPORT are organized within octets. The octets in Fig. 7B are numbered vertically and individual bites within octets are numbered horizontally. Adjacent to the octets the parameters of the elements of the SMS-SUBMIT-MANY-Report message 700 forming the corresponding octets are indicated. The TP-DC parameter is represented by an octet in which 4 bits with numbers 0 to 3 can be used.

Bits 2 to 7 in the TP-MTI octet can be unused and a corre- sponding sending short message entity, for example the SC, can put them to zero. Any non zero value within these bits causes that the remaining bits can be ignored by a corre^¬ sponding receiving short message entity, for example by the sending UE, and the TP-FCS can be treated as an "Unspecified Error Case" by the corresponding receiving short message entity, for example the sending UE. The corresponding sending short message entity can also set any other unused bits to zero and the unused bits can be ignored by the corresponding receiving identity.

In general values of the TP-MTI parameter corresponding to different types of messages are given in clause 9.2.3.1 of 3GPP TS 04.40. In addition to those given there the value 1 can be assigned to the bits 0 and 1 in case of both the SMS- SUBMIT-MANY and in the case of the SMS-SUBMIT-MANY-REPORT .

Figure 8 shows a row added to the TP-Failure Cause (TP-FCS) table from subclause 9.2.3.22 of the technical specification 3GPP TS 03.40

The possible failure reasons for a mobile originated message are included in section 9.2.3.22 of 3GPP TS 03.40 These are marked in the MO column of the TP-Failure Cause (TP-FCS) ta^¬ ble, in which table the failure reasons are indicated also together with the corresponding hexadecimal TP-FCS value inserted in the negative acknowledgement message. In case of the present invention this table is extended by adding as mentioned above the new hexadecimal TP-FCS value, e.g. C8 for the case of a non-plausible destination count parameter within the first message, and a corresponding mark in the MO column .

It should be noted that the term "comprising" does not ex^¬ clude other elements or steps and "a" or "an" does not ex^¬ clude a plurality. Also elements described in association with different embodiments may be combined. It should also be noted that reference signs in the claims should not be con^¬ strued as limiting the scope of the claims. List of abbreviations:

BSC Base Station Controller

CDMA Code Division Multiple Access

CM Connection Management

CS CauSe

CP Control Protocol

DA Destination Address

DC Destination Count

DCS Data Coding Scheme

DCV Destination Count Value

DI Dialogue Identifier TCAP

EMS Enhanced Messaging Service

FCS Failure Cause

GMSCA Gateway MSC Address

GSM Global System for Mobile Communication

HLR Home Location Register

IMSI International Mobile Subscriber Identity

IWMSCA Short Message Service Interworking MSC Address

LAI Location Area Identity

MAP Mobile Application Part

MO Mobile Originated

MR Message Reference

MS Mobile Station

MSC Mobile-services Switching Centre

MSCA MSC Address

MSISDN Mobile Station ISDN Number

MT Mobile Terminated

MTI Message Type Indicator

MUSM Multiple Users Short Message

OA Originating Address

OC Operation Code

PCI Protocol Control Information

PDA Personal Digital Assistant

PDI Protocol Discriminator

PI Parameter Indicator

PID Protocol Identifier

PLMN Public Land Mobile Network RD - Reject Duplicates

RP - Reply Path

RPDU - Reply Path Data Unit

SC - Service Centre SCA - Service Centre Address

SM - Short Message

SM-AL - Short Message Application Layer

SME - Short Message Entity

SMI - Short Message Identifier SM-RL - Short Message Relay Layer

SMS - Short Message Service

SMS-GMSC - Short Message Service Gateway MSC

SMS-IWMSC - Short Message Service Interworking MSC

SM-TL - Short Message Transfer Layer SoR - Status of Report

SRI - Status Report Indication

SRR - Status Report Request

TCAP - Transaction Capabilities Application Part

TP - Transfer Protocol TPDU - Transfer Layer Protocol Data Unit

UD - User Data

UE - User Equipment

UDL - User Data Length

VLR - Visitor Location Register VMSC - Visited MSC

VP - Validity Period

VPF - Validity Period Format

WAP - Wireless Application Protocol

Claims

Patent claims

1. A method for sending a short message from a sending user equipment (109, 209) to at least two receiving user equip- ments, the method comprising:

• sending a first message to a service centre (101, 201), wherein the first message comprises data representing des^¬ tination addresses of the at least two receiving user equipments, • sending a second message to the service centre (101,

201), wherein the second message comprises the short mes^¬ sage, and

• forwarding the short message from the service centre (101, 201) to the at least two receiving user equipments.

2. The method according to claim 1, wherein the data representing destination addresses of the at least two receiving user equipments comprises individual destination addresses of the at least two receiv- ing user equipments.

3. The method according to any of the preceding claims, fur^¬ ther comprising sending an acknowledgement message from the service centre (101, 201) to the sending user equipment a receipt of the first message.

4. The method according to claim 3, wherein the data representing destination addresses of the at least two receiving user equipments comprises a destination count parameter indicating the number of destination addresses of the at least two receiving user equip^¬ ments .

5. The method according to claim 4, further comprising checking a plausibility of the destination count parameter, and inserting a result of the plausibility check of the destina^¬ tion count parameter into the acknowledging message.

6. The method according to any of claims 3 to 5, further com- prising checking a plausibility of the first message by the service centre (101, 201), and inserting a result of the plausibility check of the first message into the acknowledgement message.

7. The method according to claim 6, wherein in case of a negative plausibility check of the first message the result of the plausibility check of the first message comprises a destination count value indicating a non-plausible destina^¬ tion address within the first message.

8. The method according to claim 6 or 7, wherein in case of a negative plausibility check of the first message the result of the plausibility check of the first message comprises a reason for which the plausibility check of the first mes^¬ sage failed.

9. The method according to any of the preceding claims, wherein the short message is sent to at most ten receiving user equipments .

10. A sending user equipment (109, 209) for sending a short message to at least two receiving user equipments, the send^¬ ing user equipment comprising:

• a first unit for sending a first message to a service cen^¬ tre (101, 201), wherein the first message comprises data representing destination addresses of the at least two re^¬ ceiving user equipments,

• a second unit for sending a second message comprising the short message to the service centre (101, 201), wherein the second message is adapted to initiate a forwarding of the short message to the at least two receiving user equip^¬ ments by the service centre (101, 201) .

11. A service centre (101, 201) for sending a short message from a sending user equipment (109, 209) to at least two re^¬ ceiving user equipments, the service centre (101, 201) com^¬ prising:

• a first unit for receiving a first message from the sending user equipment (109, 209), wherein the first message com^¬ prises data representing destination addresses of the at least two receiving user equipments,

• a second unit for receiving a second message from the send^¬ ing user equipment (109, 209), wherein the second message comprises the short message, and

• a third unit for forwarding the short message to the at least two receiving user equipments.

12. A telecommunication network comprising: a sending user equipment (109, 209) according to claim 10 and a service centre (101, 201) according to claim 11.

13. A computer program element for controlling a telecommunication network according to claim 12, wherein the computer program element, when being executed by a data processor of the sending user equipment and/or of the service centre, is adapted for implementing the method as set forth in any one of the claims 1 to 9.

14. A computer-readable medium on which there is stored a computer program element according to claim 13.