Method for establishing a data connection between first and second mobile devices

0001The invention relates to a method for establishing a data connection for transmitting data packets between a the first mobile communication terminal and a second mobile Communication terminal. Such data connections also referred to as "peer-to-peer data connections". At the Installation of such compounds may be a case, that the second mobile communication terminal is not in a data packet receivable state ( "online state") is.

0002The invention is based on the object to provide a method, with which a data connection between communication terminals can also be built if one of the communication terminals to not process beginning located in a data packet receivable state.

0003This object is achieved by a method for establishing a data connection for transmission of data packets between a first mobile communication terminal and a second mobile communication terminal, in which the process to a start message of the first data packet receive-ready Communication terminal out of a with connected to the first and the second communication terminal Communications network a short text message to the second communication terminal is transmitted to the reception the short text message comes from the second communication terminal a data packet receiving ready state is taken, and then the data connection between the first communication terminal and the second communication terminal is established. This method includes the essential idea that a short text message (Also known as SMS, SMS = Short Message Service) to the second non-data packet ready to receive communication terminal Gets transferred. It is particularly advantageous, that the transfer of such written Short message to the second communication terminal in which second communication terminal no data packet reception or no data packet receiving ready state ( "online state") is required since written short messages also at a Communication terminal can be transmitted, which not data packet receive (because, for example, currently assigned an IP address for this communication terminal is). Upon receipt of the written short message toward the second communication terminal is advantageously encouraged to take a data packet receivable state ( "On-line mode of the mobile communication terminal"). Thereupon, the data connection for transmission of data packets between the first communication terminal and the second communication terminal to be established.

0004The method can proceed so that by the second communication terminal conquered data packet receiving ready state is in which the second communication terminal a second IP address is assigned, and the data connection marked between the first by an IP address first communication terminal and the second IP address by the constructed labeled second communication terminal becomes. In this case, the data packet receivable state ( "Online state") the second communication terminal assigned its own IP address ( "second IP address").

0005The method may preferably run so that to the second communication terminal transmitted short text message the associated the first communication terminal includes first IP address of the second communication terminal the first IP address from the short text message is read out, and from the second communication terminal the data connection to the first through the IP address constructed marked first communication terminal becomes. Here it is especially advantageous that with the short text message a first communication terminal assigned first IP address is transmitted. Among Use of this first IP address and the mobile at the second Communication terminal then known second IP address can then from the second communication terminal after receipt of a written short message, the data connection between the first and the second mobile communication terminal being constructed.

0006The inventive method may also proceed so that of the first communication terminal a characteristic of the sent the second communication terminal to an address converter is, then by the first communication terminal from the address converter, the second IP address of the second communication terminal is received by the first communication terminal is checked using the second IP address, whether the data connection of the second communication terminal is built up, and the case of a positive check result Structure of the data connection is allowed, or at a canceled negative test result, the structure of the data connection becomes. It is advantageous that by first communication terminal by means of the converter of the address received second IP address can be checked whether actually the data link from communication terminal is built to the short text message was transferred. Only if this data connection actually constructed from the (desired) the second communication terminal is, by the first communication terminal is the Structure of the data connection is allowed. Otherwise, the Structure of the data connection is terminated.

0007The inventive method may also proceed so that at the first communication terminal in sending the start message a time measurement is started and just before the end a predetermined time period of the setup of the data connection is permitted. By specifying the time period during which the structure of the data link must have occurred, the Security against unauthorized making a data connection by a third party (for example, unduly into possession transmitted via the communication network messages KN1 have reached) increases.

0008The method may also proceed so that the second to the Communication terminal transmitted short text message which the first communication terminal associated with the first IP address contains, from the second communication terminal read first IP address from the short text message is, from the second communication terminal a which second IP address containing the data packet to the first IP address marked the first communication terminal is sent, and then from the first communication terminal starting the data connection is established. Thereby is advantageously achieved that to be established Data connection from the first communication terminal (that is, from the communication terminal to the process has begun establishing the data connection) is set up. Thus, the safety for the first communication terminal is increased because of this no data connection through a must accept another communication terminal.

0009In the novel process, the written Instant message with a mobile phone number of the second communication terminal be addressed. In the second communication terminal If it is in this case preferably a mobile telephone.

0010The method can proceed so that the start message a SMS message is used, and this SMS message as short text message to the second communication terminal Gets transferred. Here is the message as a Start used SMS message also the short text message. The SMS message is so as unamended short text message to the second communication terminal transfer. These may preferably the news wire mechanisms be used, which in modern mobile networks (Eg in GSM or GPRS mobile phone networks) by default provided for the transmission of SMS messages are. As a result, the inventive method can be easily and economically implemented.

0011However, the method according to the invention may also proceed so, that the start message to a gateway of the communications network is transmitted and then the short text message is transmitted to the second communication terminal.

0012The process can take place according to the invention so that by the first communication terminal, an identifier of the second communication terminal is sent to an address translator, thereupon by the first communication terminal from the Address converter the second IP address of the second communication terminal and information data about received, whether the second communication terminal at this time data packet is ready to receive, not data packet receive-ready in case of a second communication terminal the Start message is sent to the communication network, or in the case of a data packet receive-ready second communication terminal of the first communication terminal, the data connection designated to the IP address by the second the second communication terminal is set up. there is particularly advantageous that the start message only is then sent to the communication network (and hence the short text information then only to the second communication terminal is transmitted), if information data by means of informs the first communication terminal about is that the second communication terminal non-data packet ready to receive (Not "online") is. in case of a data packet receive-ready second communication terminal is the data link immediately from the first communication terminal constructed, thereby sending the start message, transmitting the short text information, etc. be superfluous.

0013In the method according to the invention can be used as indicator or a mobile phone number to be used as an identifier.

0014To further illustrate the invention will now be Method based on the figures shown in embodiments explained.

0015It is in<sl><li>Figure 1 schematically mobile communication network with two Terminals in </li><li>Figure 2 with reference to a message flow diagram an embodiment of the inventive method, in</li><li>2a shows a modified embodiment of the invention Process in</li><li>Figure 3 is a reference to a further message flow diagram Another embodiment of the method according to the invention, in</li><li>4 shows an embodiment of the method according to the invention with an SMS push message and in</li><li>Figure 5 shows another embodiment of the invention Method shown.</li></sl>

0016In Figure 1, a first mobile communication terminal KEG 1 and a second mobile communication terminal in the form KEG2 each represented a mobile telephone. In another embodiment, may it be in the mobile communication terminals but also, for example, palmtops, Personal Digital Assistants (PDAs), or portable computer with a mobile interface act. In this embodiment, is the first communication terminal in the form of a mobile phone KEG1 in a known manner via an air interface connected to a communications network KN1, which is the exemplary embodiment is a GPRS cellular network (GPRS = General Packet Radio Service) is. From this communication network KN1 are shown only selected elements: A switching center GGSN (GGSN = GPRS gateway service node), an address converter (DNS domain name server) a proxy gateway PPG for the so-called "push service" (PPG = Push Proxy Gateway) and a service center SMSC for writing short messages (SMSC short message service center, message center). The communications network KN1 is connected to the second mobile communication terminal KEG 2. The interaction of the elements of the communication network for performing the method according to the invention for constructing a data connection is below in connection explained with Figures 2 to 4. FIG.

0017In Figure 2 is based on a message flow diagram a first embodiment of the method according to the invention shown. is on the mobile communication terminal KEG 1 an IP-based (IP = Internet Protocol) peer-to-peer application program started, which together with a peer-to-peer application program ( "Target application") of the second mobile Communication terminal KEG 2 a data link between to realize the mobile communication terminals. In such a peer-to-peer application program (also briefly called peer-to-peer application) of the first communication terminal it may, for example, a photo management program act, which means the first communication terminal KEG 1 created photos directly via a data connection to a similar peer-to-peer application program in the form a photo management program of the second communication terminal to transmit KEG 2.

0018The well-known at the first communication terminal KEG 1 (for example, from a user input) Mobile Phone MSISDN (MSISDN = Mobile Station ISDN Number) of the second Communication terminal KEG 2 is from the application program the first communication terminal KEG 1 from the E.164 format (Eg +49 172 1234567) in the ENUM-format (eg 7.6.5.4.3.2.1.2.7.1.9.4.e164.arpa) converted. In this ENUM format is the mobile phone number MSISDN of the second Communication terminal KEG 2 (an identifier or a Plate the second communication terminal KEG 2 represents) of the first communication terminal KEG 1 means a message "DNS request" to an address converter DNS transmitted the communication network. Along with this mobile phone number is also a first IP address IP1 of the first transmitted the communication terminal to the address converter DNS. (Also known as address resolution) to address implementation is used a per se known "Domain Name Server" DNS.

0019The address translator DNS determined using the mobile phone number MSISDN in a conventional manner, the second IP address IP2 of the second communication terminal KEG 2 and the information, whether the second communication terminal to this Time data packets ready to receive ( "online") is. This determination the data packets are willing to receive is as "Query the online status" since the address translator this information in a conventional manner by another Network element of the communication network KN1 (for example, from a not shown HLR, a RADIUS authentication server, a presence server or interrogates a multimedia subsystem IMS). The Online Status ( "KEG 2 is online" or "KEG 2 is not currently online") is of the Address translator DNS to the first communication terminal KEG 1 transmitted. Furthermore (if known) is the second IP address IP2 of the second communication terminal KEG 2 to the first communication terminal KEG 1 transfer.

0020When the second communication terminal KEG 2 data packet ready to receive ( "Online"), then is transmitted from the first communication terminal the data connection directly to the second IP address IP2 labeled second communication terminal KEG 2 built (this case is shown in Figures not shown). In this case, unnecessary in the following described process steps and the structure of the Data connection has been completed.

0021In the event that the second communication terminal KEG2 no data packet receive (not "online") is created the first communication terminal KEG 1 a Start message and sends it to the communications network from KN1. In which in the Figure 2 illustrated embodiment, as the start message generates a message which a special format having. This SMS message has namely a so-called "UserDataHeader" (UDH / TP UDHI) on as example from the document 3GPP TS 23.040, V6.2.0, Technical Specification, 3rd Generation Partnership Project; Technical Specification Group Terminals; Technical realization of the Short Message Service (SMS) is known. Of the Communications network KN1 is this start message unchanged Form as a short text message SMS to the second Communication terminal KEG 2 transfer. In this written Short message SMS is the first IP address IP1 of the first Communication terminal KEG 1 as well as information on the application program ( "target application") of the second communication terminal KEG 2 contain that to be established at the to participate data connection.

0022After sending the start message takes the application program the first communication terminal KEG 1 a wait state and waits (for example on a UDP or TCP port) on a second of the communication terminal KEG2 incoming message. By sending the Start message SMS is at the first communication terminal KEG 1 (for example, by starting a timer) a time measurement began. Only those of the second communication terminal KEG 2 incoming messages within a predetermined Period of time T to arrive, can for establishing a data connection to lead.

0023The short text message SMS is now second from the Communication terminal KEG 2 received. Due to the special Format of this short text message (eg. As a result the User Data Header), this short text message but not as one for the human user the second communication terminal KEG 2 specific written Short message addressed (ie it is for example not a display device of the second communication terminal displayed), but this the special format containing short text message is of the SMS stack of the second Communication terminal KEG 2 away. Then, by the second communication terminal KEG 2 a user dialog started by, for example, on the display unit of the second communication terminal the text "Do you want a establish the online connection? "is displayed. When a user the second communication terminal KEG 2 online data connection not want to create an appropriate and Key (for example, the "0" key, meaning "no") the communication terminal KEG 2 is operated, be of the second communication terminal KEG 2 no further steps more run to establish the data connection. Then running at the first communication terminal KEG 1 launched timer when reaching the predetermined Period from T; upon expiration of this timer is also at the first communication terminal KEG1 terminates the process.

0024If the user but make the on-line data connection want and a corresponding key (such as the "1" key with actuated meaning "Yes"), then by the second communication terminal a data packet receiving ready state occupied. To obtain such a data packet receive-ready State ( "Online" state) is of the second Communication terminal KEG 2 a per se known PDP Context (PDP = Packet Data Protocol) to the switching point GGSN built up. Thereby, the second communication terminal allows KEG2 reception of IP data packets; it will be one Online connection to the communications network KN1. From the exchange GGSN receives the second communication terminal KEG 2, the second IP address IP2 allocated.

0025From the second communication terminal is determined from the KEG2 short text message SMS to the first communication terminal read KEG1 assigned first IP address IP1 and using this first IP address IP1 and the second IP address IP2, the data connection to the DV by the first IP address IP1 marked the first communication terminal KEG 1 up. The structure of this data link DV is in this embodiment, ie by the second communication terminal KEG 2 controlled. When the data connection can be either in a connection-oriented Data connection (for example, a TCP data connection, TCP = Transmission Control Protocol) or a connection-less data link (for example, a UDP data connection, UDP = user datagram protocol) act. provided this data connection before the expiration of the timer the communication terminal KEG 1 measured predetermined Time period is established, the establishment of the data connection is authorized by the first communication terminal KEG1.

0026In an alternative embodiment of the invention Method, at the start of the second communication terminal by KEG 2 controlled structure of the data connection from the first communication terminal (on the basis of of the Address translator DNS to the first communication terminal KEG 1 transmitted second IP address IP2) are checked whether the data link DV actually of the second communication terminal KEG 2 is constructed. At the start of building the data link divides namely the second communication terminal KEG 2 which this assigned second IP address IP2 to the first communication terminal KEG 1 with. Only with a positive Check result (that is when the second of the communication terminal KEG 2 sent second IP address IP2 with the information provided by the address converter DNS second IP address IP2 matches) is the part of the first communication terminal KEG 1, the structure of the data connection is allowed. Otherwise, the structure of the data connection is terminated.

00272a shows a further embodiment is shown, the embodiment is described by the means of Figure 2 differs in that the address converter DNS to query the online status of the short text information SMS to the second communication terminal KEG 2 sends. The corresponding subsequent process steps again the steps shown in FIG. 2

0028In Figure 3 is a further embodiment of the invention Method shown. This embodiment differs from that in connection with the Figure 2 embodiment explained by the fact that of the Address translator DNS only the online status of "not online" to the first communication terminal KEG 1 is transferred, not However, the second IP address IP2. This may occur if a dynamic (eg occasionally changing) assignment of IP addresses to the second communication terminal KEG 2 is done. Furthermore, this embodiment is different illustrated by the figure 2 in connection with the Embodiment in that, after construction of the PDP context and after receiving the second IP address IP2 by the second communication terminal KEG 2 a data packet (IP packet) which contains the second IP address IP2, to which the first IP address IP1 marked the first communication terminal Sending KEG 1. is Upon receipt of this data packet the first communication terminal KEG 1, the second IP address IP2 of the second communication terminal is known, and it will then, starting from the first communication terminal KEG1 (Controlled by the first communication terminal KEG1) the data link between the first communication terminal KEG 1 and the second communication terminal KEG 2 built.

0029In Figure 4 is another example of a process flow shown in which a start message a message PS "Push Submission" using the PAP + / HTTP protocol (PAP + is an extension of the PAP protocol, PAP = Push Access Protocol, HTTP = Hypertext Transfer Protocol) to the transmitted proxy gateway PPG the communications network KN1 becomes. An ENUM address resolution is not necessary here. In this example, a push service ( "unconfirmed push") is the mobile phone number MSISDN as indicator for addressing used as an alternative, other indicator are used as addresses (eg e-mail addresses from be resolved Gateway PPG). This includes starting message PS next to the first IP address IP1 also information on the establishment of data connection to the second communication terminal KEG 2-to-use application software (application software). The proxy gateway PPG receives the Start message PS and checked the online status of the user (For example, using a not shown in the figure WAP gateway or a RADIUS server). If the second communication terminal KEG 2 "online" is not, then transfers the proxy gateway PPG then an SMS push message SMSP ( "SMS Push Message") to the second communication terminal KEG 2 using the protocol "Push Over-the-air protocols (Push OTA) ". (The push OTA protocol may be different "Bearer" (as SMS or GPRS) operate. When the second Communication terminal KEG 2 is not "online", then sends the proxy gateway PPG the push message SMSP - as described above -. By SMS from) The short text message SMSP is therefore in the form of an SMS-push message from the Proxy Gateway PPG via the service center SMSC to the second Communication terminal KEG 2 received. By the proxy gateway PPG is then (optionally) an acknowledgment message B "Result Notification" on the first communication terminal KEG 1 sent. Performing the user dialog and the structure of the PDP context then take place analogously to that in connection with Figure 2 described method. Since by means of the written Newsflash SMSP also information about the in the first communication terminal KEG1 build the data connection to use application software to the second Communication terminal KEG 2 was transmitted, can now by the application software of the second communication terminal KEG 2 directly the data connection to the application software the first communication terminal KEG 1 are constructed. The protocols push OTA and PAP are from the specifications "WAP-235-PushOTA-20010425-a" and "WAP-247-PAP-20010429-a" the Open Mobile Alliance (OMA) known.

0030In Figure 5 is another example of a process flow shown in which a start message a message PS "Push Submission" using the PAP + / HTTP protocol transfer the proxy gateway PPG of the communications network KN1 becomes. In contrast to the means of Figure 4 discussed The method transmits the first communication terminal KEG 1 with Message PS (adjacent to the first IP address IP1 of the information and on the establishment of data connection on the second communication terminal KEG 2-to-use application software) in addition, the information that the delivery method to use "confirmed push". The proxy gateway PPG receives (as in the figure in connection with the 4 methods explained), the start message PS and checked the online status of the user or the second communication terminal KEG 2 (eg using an in the figure not shown WAP gateway or a RADIUS server). When the second communication terminal KEG 2 is not online, then transmits the Proxy Gateway PPG an information message SMSN ( "SMS Push (notification)") to the service center SMSC. Then sends the service center SMSC as written Short message SMS push message PSMS (which also is referred to as "session initialization request") under Use of the Push-Over-the-air protocols (Push OTA) to the second communication terminal KEG 2. After receiving the SMS push message PSMS builds the second communication terminal KEG 2 a PDP context, and calls for a further push message, which the first IP address IP1 and the information contains on the application software from the proxy gateway PPG from ( "Retrieve Push Message"). Then confirmed the second communication terminal KEG 2 receiving this further Push message ( "Confirm Push Message"). By the proxy gateway PPG is then (optionally) an acknowledgment message B "Result Notification" on the first communication terminal KEG 1 sent. Performing the user dialogue and the structure of the data connection is then analog to those described in connection with the Figure 2 and Figure 4 Process.

0031It has been a method for establishing a data connection to the Transmission of data packets between mobile communication terminals described which has a number of advantages. On the part of the first communication terminal KEG 1 can (by means of the start message) of establishing a data connection led to the second communication terminal KEG 2 be, even if this second communication terminal KEG2 no PDP context has built, not "online" and thus not data packet to receive. This method can be carried out even if the second communication terminal KEG 2 dynamic IP addresses are assigned. This is advantageously by the address resolution in the domain name server DNS allows using the ENUM procedure. Since the delivery of short text messages in general to be paid by sender (here from the first communication terminal KEG1), the probability of a Abuse of process (for example, for mass Constructing data connections for transmitting unwanted Advertising messages) reduced.