GB2398204A

GB2398204A - Setting communication types for a communication session

Info

Publication number: GB2398204A
Application number: GB0302568A
Authority: GB
Inventors: Stephen Jan Wolak; Peter Richard Thompson
Original assignee: Vodafone Group PLC
Current assignee: Vodafone Group PLC
Priority date: 2003-02-04
Filing date: 2003-02-04
Publication date: 2004-08-11
Anticipated expiration: 2023-02-04
Also published as: GB0302568D0; GB2398204B

Abstract

The invention relates to a mobile communications network having an Internet-Protocol Multimedia Subsystem (IMS). Once a SIP session has been established between two or more end points or users, communication can be carried out using a variety of different protocols, i.e. for streaming audio or video. A method of establishing a communication session between a first terminal 1 supporting a first plurality of communication types, and a second terminal 3 supporting a second plurality of communication types is disclosed. The method includes determining at least one type common to both terminals, enabling communication between said terminals by one of said common communication types, and allowing the communication type to be changed to another of said common types during the session.

Description

SETTING COMMUNICATION TYPES FOR A COMMUNICATION SESSION

The present invention relates to session-based communication, and in particular to allowing the selection of an appropriate communication type (voice, video etc.) from the available communication types for use during a communication session. The embodiment to be described concerns selecting a communication type in a system using Session Initiation Protocol (SIP).

The third generation partnership project (3GPP) has recently defined a new concept known as IMS: IP (Internet Protocol) - based Multimedia Subsystem. The aim of IMS is to allow users such as mobile telephone network operators to provide services to their subscribers as efficiently and effectively as possible. For example, the IMS architecture is likely to support the following communication types: voice, video, instant messaging, "presence" (a user's availability for contact), location-based services, email and web.

Further communication types are likely to be added in the future.

The SIP protocol is a session-based protocol designed to establish IP based communication sessions between two or more end points or users. Once a SIP session has been established, communication between these end points or users can be carried out using a variety of different protocols (for example those designed for streaming audio and video). These protocols are defined in the SIP session initiation messages.

The present invention is concerned with allowing an appropriate communication type to be selected prior to the SIP session, and further to allowing the communication type to be altered during an SIP session.

According to a first aspect of the present invention, there is provided a method of establishing a communication session between a first terminal supporting a first plurality of communication types and a second terminal supporting a second plurality of communication types, the method including determining which of said first plurality of communication types are common to said second plurality of communication types, enabling communication between the first and second terminals by one of said common communication types, and allowing the communication type to be changed to another of said common communication types during the session.

According to a second aspect of the invention, there is provided a communication system for establishing a communication session between a first terminal supporting a first plurality of communication types and a second terminal supporting a second plurality of communication types, the system including means for determining which of said plurality of said first communication types are common to said second plurality of communication types, means for enabling communication between the first and second terminals by one of said common communication types, and means for allowing the communication type to be changed to another of said common communication types during the session. 3 l

The invention also relates to a terminal for use with the system.

A method of and system for establishing a communication session, and a suitable terminal, embodying the invention will now be described by way of example, with reference to the accompanying drawings, in which: Figure 1 shows schematically the elements of a communication system which allows communication between terminals managed by SIP; and Figure 2 shows the data communicated between a terminal, a SIP network server, a home subscriber server (HSS) and a further terminal.

The communication system of Figure 1 allows communication between a mobile telephony enabled PDA (Personal Digital Assistant) 1, a mobile telephone 3 and a PC (Personal Computer) 5. The PDA1 and mobile 3 subscribe to and communicate via 3G mobile telephone network 7. The PDA 1 and the mobile 3 are capable of IF based communications using SIP.

A SIP server 9 allows SIP based communication between the PDA 1 and mobile 3 via the 3G network 7.

In a known manner, PDA I begins a communication session by the PDA 1 issuing an SIP 4 l INVITE message addressed to the user name of the mobile 3. The user name is transmitted wirelessly by 3G network 7 to the SIP server 9. The SIP server 9 determines the current location of the user name associated with mobile 3 and provides the current network address for the user name associated with mobile 3. A communication session may then commence between the PDA 1 of the mobile terminal 3 via 3G network 7. This is how a SIP communications network operates conventionally.

In accordance with a feature of the present invention prior to issuance of the SIP INVITE message, which begins the communication session, a preliminary MEDIA- NEGOTIATION message, which is not part of the session, is issued by the PDA 1 as part of a hand-shaking process. The media negotiation message is of the same format as a conventional SIP INVITE message. However, the media negotiation message contains a I "flag" recognizable by the SIP Server 9 and mobile 3 to denote that it is not a conventional SIP invite message. The media negotiation message lists the communication types supported by the PDA 1 and includes the user name of mobile 3. The media negotiation message is passed via 3G network 7 to the SIP server 9. Initially, the SIP server 9 compares the communication types supplied by the PDA 1 with a profile for the user of PDA 1 stored in a Home Subscriber Server (HSS) 11. The user profile includes information relating to the various services that the user of PDA 1 has subscribed to (i.e. paid for). If the information stored on the HSS It indicates that some of the communication types supported by the PDA l are not available to the subscriber of PDA 1, then only a subset of the relevant communication types supported by the PDA 1 is available to the subscriber. The list of communication types available to the subscriber is then transmitted to mobile 3 using the address information obtained in the SIP server 9 in accordance with the user name provided for the mobile 3.

The mobile 3 responds by sending a list of the communication types that it supports to the SIP server 9 via the 3G network 7. Again, a check is made to the HSS 11 to determine whether any of the communication types supported by the mobile terminal 3 are not available to the subscriber, and the available communication types are then provided to the PDA 1 via the 3G network 7.

PDA I then issues a SIP INVITE message for mobile 3 to initiate a communication session in the conventional manner. However, in accordance with a feature of the invention, the PDA 1 is aware of the communication types supported by and available to the mobile 3, and likewise the mobile 3 is aware ofthe communication type supported by and available to the PDA 1.

Initially, the Communication session will begin using a default communication type indicated in HSS 11 - for example, voice communication - or with a communication type selected on any suitable basis. However, because PDA 1 is aware of the other communication types that are supported by both the PDA l and the mobile 3, these communication types can conveniently be displayed on the display panel 13 of the PDA l at positions 15 and l7 associated with respective "soft keys" 19 and 21. A soft key is a key whose function may be changed by re-programming the key. The soft keys 19 and 21 are programmed so that on actuation of the relevant key a request is issued via the 3G network 7 to the mobile terminal 3 to change to the communication type indicated to be associated with that soft key by the respective messages at positions 15 and 17. Typically the user of mobile 3 will then be given a prompt to accept the new communication type by pressing one of the soft keys 23,25.

In a similar manner, the user of mobile 3 may change communication types by actuating soft keys 23 and 25 provided on the mobile 3, the communication types associated with which are indicated by the portion of the display 27 immediately above those keys.

Of course, it should be appreciated that a selection of the available communication types does not have to be provided by means of soft keys. The various communication types could be viewed and selected using a menu or any other suitable user interface.

Optionally, a user may indicate which communication types are preferred, for example by giving each available communication type a ranking. This ranking may be stored either with the list of supported communication types in the PDA 1/mobile 3 or in the HSS I 1.

When the media negotiation process between the PDA 1 and the mobile 3 has been completed, only the preferred of the commonly available communication types may be displayed, or all the available communication types may be displayed in a particular order - indicating the preference for the various communication types available. For example, the most preferred communication type might be displayed on the leftmost part of the display panel 13 and/or highlighted in some way. The HSS 11 may additionally or alternatively indicate which communication types are preferred by the 3G network 7 (for example, these could be communication types which make the most efficient use of the available network capacity). Further, the SIP server 9 may intervene in the way that the communication types are displayed to the users of the PDA 1 and mobile 3 at times of congestion in the 3G network 7 to suggest to the users to select a communication type which requires the transmission of less data.

In the example described above, the PDA I and the mobile terminal 3 are in the same "domain". In the event that the user of PDA 1 wishes to communicate with the user of PC5, which is in a different domain, the user name is provided via the 3G network 7 to the SIP server 9 as before. The SIP server 9 determines that the user name associated with the PC5 is not one within the domain of the SIP server 9. The message from the PDA 1 is then passed to a second SIP server 29 which is associated with a second domain.

The second SIP server 29 includes a HSS 31 similar to the HSS 1 1 of the first SIP server 9. The second SIP server 29 provides the current address within the second domain of the PC5 which allows the transmission of messages from the PDA 1 to the PC5 via Internet connection 33. Communications between the PC5 and the PDA 1 will pass successively through the Internet 33, the second SIP server 29, first SIP server 9, 3G network 7. To initiate a communication session between the PDA I and the PC5 the commonly available communication types are determined using the MEDIA NEGOTIATION command, and the session is initiated with the SIP INVITE command, as before.

The PDAl, mobile 3 or PC5 may periodically be provided with updated communication type availability information by receiving further media negotiation messages during a communication session, which media negotiation messages originate from the or each client with which they are communicating in the session.

A specific example of a communication session between PDA 1 and mobile 3 will now be described. PDA 1 issues a MEDIA NEGOTIATION message addressed to mobile 3. As described above, the communication types supported by the respective devices and in accordance with the subscription level the relevant subscribers have with the network 7 are determined. In this example, the result of the media negotiation process is that both the PDA 1 and the mobile 3 know that audio as well as instant messaging communication types are commonly supported and available. The communication session, which is initiated by the sending of a SIP lNVlTE message, then commences with an instant messaging conversation (this being selected initially as the default communication type stored in HSS l l or being determined to be the most preferred communication type). As a result of the media negotiation process, both the PDA 1 and the mobile 3 display a message "voice" above the leftmost soft key 19,23. The soft key 19,23 is programmed such that by actuating; the key, a message is sent to the communicating device with a request to change the communication type to audio communication. At any time during the communication session, the users of PDA 1 and mobile 3 have a visual indication of the communication types supported by and available to the other device, which negates the need for negotiations during the communication session to establish which communication types are available and supported, which may delay communications between the two devices.

If the user of PDA 1 wishes to change the communication session to an audio session, instead of instant messaging, the user actuates soft key 19 on PDA 1, and this triggers the sending of a SIP RE-INVITE message to mobile 3. The user of PDA 1 knows that the change of communication type should be accepted by mobile terminal 3 by virtue of the media negotiation process that occurred prior to the communication session.

In addition to controlling the communication types displayed on a terminal for selection by a user in dependence upon the communication types supported by the terminal and the subscriber information stored on the HSS, the communication types displayed may be varied based on other criteria. For example, the terminal may have a plurality of selectable modes suitable for use in particular circumstances - such as "meeting", "home", "outdoors" etc. The communication types displayed could be altered depending on the mode selected. For example, if the selected mode is "meeting", the terminal could appropriately indicate the preferred communication type to be instant messaging because voice or video communication would be disruptive to a meeting.

Figure 2 shows the exchange of messages between the PDA 1, SIP server 9, HSS 1 1 and mobile 3 up to transmission of the SIP INVITE message.

Claims

1. A method of establishing a communication session between a first terminal supporting a first plurality of communication types and a second terminal supporting a second plurality of communication types, the method including determining which of said first plurality of communication types are common to said second plurality of communication types, enabling communication between the first and second terminals by one of said common communication types, and allowing the communication type to be changed to another of said common communication types during the session.

2. The method of claim 1, including indicating to the user of the first andlor second terminal at least a selection of said common communication types.

3. The method of claim 2, wherein said indication is a visual indication.

4. The method of claim 2 or 3, wherein at least one of said first and second terminals is adapted to display at least a selection of said common communication types in association with a programmable selection means, the operation of which selects a required common communication type for use during the session.

5. The method of any one of the preceding claims, wherein, prior to the communication session between the first and second terminals, the determining step is performed and a selected one of said common communication types is used at the initiation of said session.

6. The method of any one of the preceding claims, wherein the communication types are selected from: voice, video, instant messaging, "presence" (a user's availability for contact), location-based services, email and web.

7. The method of any one of the preceding claims, wherein the communication session is a Session Initiation Protocol (SIP) session.

8. The method of any one of claims 2 to 7, wherein the indicating step includes indication which of said common communication types are preferred communication types.

9. The method of claim 8, wherein the communication preferences are determined by the user of the first and/or second terminal.

10. The method of any one of the preceding claims, wherein the communication medium for the communication session is the internet.

The method of any one of claims 1 to 9, wherein the communication medium for the communication session is a telephone network.

12. The method of any one of claims 1 to 97 wherein the communication medium for the communication session is a mobile telephone network.

13. The method of claim 127 wherein the mobile telephone network is a GSM network.

14. T he method of claim 12, wherein the mobile telephone network is a 3G network.

15. The method of any one of claims 8 to 14, wherein communication preferences are determined by the communication medium.

16. The method of any one of the preceding claims, wherein the determining step includes determining the communication types supported by the communication medium for the first andlor second terminal.

17. The method of any one of the preceding claims, wherein the determining step is performed by sending a special signal from the first terminal to the second terminal indicative of the communication types supported by the first terminal.

18. The method of claim 17, wherein subscription control means is provided for receiving the special signal prior to transmission to the second terminal and for modifying the special signal in accordance with the communication types to which the subscriber of the f rst terminal has subscribed.

] 9A The method of claim 17 or 18, wherein the determining step further comprises sending a special signal from the second terminal to the first terminal indicative of the communication types supported by the second terminal.

20. The method of claim 7, wherein the determining step includes sending a message in the format of a SIP INVITE message but including a flag to allow the message to be distinguished from a SIP INVITE message.

21. A communication system for establishing a communication session between a first terminal supporting a first plurality of communication types and a second terminal supporting a second plurality of communication types the system including means for determining which of said plurality of said first communication types are common to said second plurality of communication types, means for enabling communication between the f rst and second terminals by one of said common communication types, and means for allowing the communication type to be changed to another of said common communication types during the session.

22. The system of claim 21, including sending a signal to the first and/or second terminal for causing that terminal to indicate at least a selection of said common communication types.

23. The system of claim 22, wherein said indication is a visual indication.

24. The system of claim 21, 22 or 23, wherein the determining means selects one of said common communication types for use at the initiation of said session prior to commencement of the communication session between the first and the second terminals.

25. The system of any one of claims 21 to 24, wherein the communication types are selected from: voice, voice, instant messaging, "presence" (a user's availability for contact), location-based services, email and web.

26. The system of any one of claims 21 to 25, wherein the communication session is a Session Initiation Protocol (SIP) session.

27. The system of any one of claims 22 to 26, wherein the signal is sent to the first and/or second terminal causes the or each terminal to indicate which of said common communication types are preferred communication types.

28. The system of claim 27, wherein the communication preferences are determined by the user of the first and /or second terminal.

29. The system of any one of claims 21 to 28, wherein the communication medium for the communication session is the Internet.

30. The system of any one of claims 21 to 28, wherein the communication medium for the communication session is a telephone network.

31. l he system of any one of claims 21 to 28, wherein the communication medium for the communication session is a mobile telephone network.

32. The system of claim 31, wherein the mobile telephone network is a GSM network.

33. The system of claim 31, wherein the mobile telephone network is a 3G network.

34. l he system of any one of claims 27 to 33, wherein communication preferences are determined by the communication medium.

35. T he system of any one of claims 21 to 34, wherein the determining means includes means for determining the communication types supported by the communication medium for the first andlor second terminal.

36. The system of any one of claims 21 to 35, wherein the determining means receives a special signal from the first terminal indicative of the communication types supported by the first terminal. 17 1

37. The system of claim 36, further comprising subscription control means for receiving the special signal and for modifying the special signal in accordance with the communication types to which the subscriber of the first terminal has subscribed prior to onward transmission of said special signal to the second terminal.

38. The system of claim 36 or 37, wherein the determining means receives a special] signal from the second terminal indicative of the Communication types supported by the second terminal.

39. The system of claim 26, wherein the determining means comprises means for issuing messages in the format of a SIP INVITE message but including a flag to allow the message to be distinguished from a SIP INVITE message.

40. A terminal for use in the system of any one of claims 22 to 39 including means for receiving and interpreting the signal indicative of said common communication types and adapted to display at least a selection of said common communication types in association with a programmable selection means, the operation of which selects a required common communication type for use during the communication session.

41. The terminal of claim 40, wherein the programmable selection means is a soft key.

42. A method of establishing a communication session substantially as hereinbefore described with reference to and/or substantially as illustrated in any one of or any combination of the accompanying drawings.

43. A system for establishing a communication session substantially as hereinbefore described with reference to and/or substantially as illustrated in any one of or any combination of the accompanying drawings.

44. A terminal substantially as hereinbefore described with reference to and/or substantially as illustrated in any one of or any combination of the accompanying drawings.