HK1252016B - Merging active group calls - Google Patents

Description

Merge Active Group Calls

Priority claim

This application claims priority to U.S. Patent Application No. 14/754,218, filed June 29, 2015, which is hereby incorporated by reference in its entirety.

Technical Field

The present disclosure relates to data transmission in a wireless communication system, and more particularly to merging active group calls.

Background Art

In some cases, a push-to-talk (PTT) service can provide an arbitration service for two or more users participating in a communication. For example, a user in a group call can request permission to send media, such as voice, video, or other multimedia content. In some cases, a user can request permission by pressing a button on a device, which sends a request to a server. The server can determine whether the permission sent by the user is authorized and send an authorization message to the user. Examples of PTT services may include mission-critical PTT (MCPTT) services that may be applicable to mission-critical scenarios. In some cases, the MCPTT service may use the Third Generation Partnership Project (3GPP) transport communication mechanism provided by the Evolved Packet System (EPS) architecture to establish, maintain, and terminate the actual communication path between users. In some cases, the MCPTT service may use non-3GPP (e.g., scheduler or administrator) access technology and architecture. Examples of PTT services may also include non-mission-critical PTT services.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is an example wireless communication system for merging active group calls, according to an embodiment.

2 is a data flow diagram illustrating an example process for merging active group calls, according to an embodiment.

FIG3 illustrates an example subscription request, according to an embodiment.

FIG4 illustrates an example notification message according to an embodiment.

FIG. 5 shows an example portion of a notification message indicating bearer information according to an embodiment.

FIG6 illustrates an example portion of a notification message indicating a pending request, according to an embodiment.

7 is a data flow diagram illustrating an example process for merging active group calls using a broadcast message, according to an embodiment.

8 is a block diagram of an example computer that may be used to merge active group calls, according to an embodiment.

9 is a flow chart illustrating an example method for merging active group calls.

FIG. 10 illustrates an example ad hoc PTT group call.

FIG. 11 illustrates an example pre-scheduled PTT group call.

FIG. 12 illustrates an example chat PTT group call.

Like reference numerals and designations in the various drawings indicate like elements.

DETAILED DESCRIPTION

The present disclosure relates to merging active group calls. In some cases, multiple PTT groups may be temporarily merged. For example, when an event occurs in an area, different PTT groups may be merged so that members of these different PTT groups can communicate with each other. In some cases, ad hoc groups or pre-arranged groups can be formed to include different PTT groups. An ad hoc group call is a group call that includes group members in the request to initiate the call. A pre-arranged group is a group that pre-defines a list of member groups and initiates a call by including a URI associated with the group in the request to initiate the call. Users in these different PTT groups can be invited to join the ad hoc group call or pre-arranged group call. After the event, the ad hoc group call or pre-arranged group call can be canceled.

In some cases, two or more PTT groups have active group calls and wish to merge their active group calls in a merged group call. Using an ad hoc group call or a pre-scheduled group call to merge a call may lose the state of the active group call. For example, the ad hoc group call or pre-scheduled group call method can invite all members of the PTT group, including members not participating in the current active group call. In addition, metadata information (e.g., queue information) of the active group call may be lost in the ad hoc group call or the pre-scheduled group call.

In some cases, a group type called a chat group can be used for PTT calls. Unlike ad hoc or pre-arranged groups where members of a chat group are invited to join a group call at the start of the call, group members must request to join (similar to how they dial in to a conference).

In the case of a pre-arranged chat group and a list of authorized members who will be invited or allowed to join the group call, the authorized members may have to attach to the group to indicate their current interest in being invited to the group call. The active participants in the group call may be a subset of those members attached to the group, as some attached members may not be able to participate in the call (e.g., due to being out of radio coverage or the user not accepting the invitation to join).

In some cases, it may be necessary to merge multiple chat groups, and the authorized member from other groups may attempt to join the chat group call (for example, by sending an invitation to the PTT server to join the chat group call by the server supervisor) that merges. Yet, the supervisor server of chat group call may not access the group information of other PTT groups of its active group call in charge in different servers, for example, member list. Therefore, the supervisor server may not invite or authorize the member from other PTT groups to join the chat group call. In addition, the authorized member of chat group may not know that this chat group has been merged into the temporary chat group call. Therefore, it is necessary to have a kind of means to indicate that the chat group has been merged into the temporary chat group call to all authorized members, or to redirect the member who attempts to join the original chat group to be that they need to join the temporary chat group call that merges.

FIG1 illustrates an example wireless communication system 100 for merging active group calls according to an embodiment. For example, a first push-to-talk (PTT) server may already be hosting a first active group call or in the process of establishing a new group call comprising multiple groups. A first group of PTT clients may already be participating in the first active group call. The first PTT server may need to invite a second group of PTT clients as part of establishing a new group call comprising multiple groups, or may receive a request to invite a second group of PTT clients to an already established group call. The request to establish a new group call comprising multiple groups or the request to invite a second group of PTT clients may include an identifier for the second group of PTT clients. The first PTT server may send a first invitation message to a second PTT server. The second PTT server may be hosting a second active group call. The first invitation message may include an identifier for the second group of PTT clients. The second group of PTT clients participates in the second active group call. In response to the first invitation message, the first PTT server may receive a response message containing a list of members of the second group. The response message may indicate which members of the second group of PTT clients are affiliated with the group. The response may indicate that the group is currently participating in the active group call. The response message may indicate which members of the second group of PTT clients are participating in the second active group call.

In some embodiments, the first PTT server may send a second invite message. The second invite message may invite at least one PTT client in the second group of PTT clients to the merged PTT group call. The second invite message may indicate that the merged PTT group call replaces or suspends the second active group call. In some cases, multiple instances of the second invite message may be sent separately and addressed to each PTT client in the second group of PTT clients. In some cases, the second invite message may be sent via a Multimedia Broadcast/Multicast Service (MBMS) channel.

In some embodiments, the first invitation message to the second PTT server may include an indication to the second PTT server that if the group is already in an active call, a second invitation message sent by the second PTT server to the second group of PTT clients requests to join the merged PTT call. In this case, the first and second invitation messages include the necessary identifiers for the PTT clients to join the merged PTT call.

In some embodiments, the first PTT server may send a subscription request to the second PTT server. In response to the subscription request, the first PTT server may receive a notification message. The notification message may include metadata for the second group of PTT clients. In some cases, the metadata may indicate one or more pending requests to send media from members of the second group of PTT clients. The pending requests may be received at the second PTT server before the first invitation message. In some cases, the metadata may indicate at least one of a timestamp, a queue position, or a priority of each of the pending requests. In some cases, the metadata may indicate a multimedia broadcast/multicast service (MBMS) bearer used by at least one PTT client in the second group of PTT clients for the second active group call.

The first PTT server may host a merged PTT group call that may have participants from the first group of PTT clients and the second group of PTT clients.

Merging active group calls according to the methods and systems described herein can provide one or more advantages. For example, call state information for the second group call is transmitted to the first PTT server. Thus, the first PTT server can invite only affiliated members or those members actually participating in the second group call. In some cases, a group may have a large number of authorized members, but a much smaller number of actual affiliated members and active participants, thus providing a significant advantage in inviting only affiliated members of the group or active participants in the group call. Additionally, the first PTT server can obtain information about pending requests in the second group call and can process these pending requests in the merged call, merging pending requests from the first group call with pending requests from the second group call based on the timestamps, relative queue positions, and/or priorities of the requesting participants from both group calls. Furthermore, using the MBMS channel to invite members participating in the second group call to the merged call can save resources and improve the efficiency of the communication system, as it would be impractical to invite a large number of participants individually within a reasonable timeframe.

At a high level, an example wireless communication system 100 includes a wireless communication network 110 that includes a first group of PTT servers 102 and a second group of PTT servers 112. The example wireless communication system 100 also includes user equipment (UE) 106a-c and UE 116a-b. In some cases, each of UE 106a-c and UE 116a-b can include a PTT client. The wireless communication system 100 can also include UEs that are non-wireless devices, such as PTT dispatch stations, that can be connected to a wireless network using fixed access technologies such as Ethernet or WLAN. A PTT client can refer to an application, a set of applications, software, a software module, hardware, or a combination thereof that can be configured to communicate with a PTT server for PTT services. As shown, UE 106a-c is included in the first group 104, and UE 116a-b is included in the second group 114. In some cases, the first group 104 has a first ongoing group call in which the UEs 106a-c participate, and the second group 114 has a second ongoing group call in which the UEs 116a-b participate.

The example wireless communication system 100 also includes a first PTT server 102 that hosts a first group of calls, and a second PTT server 112 that hosts a second group of calls. In some cases, the PTT server (e.g., the first PTT server 102 or the second PTT server 112) can provide participation functionality, control functionality, termination functionality, or a combination thereof for the PTT service. For example, in some cases, the PTT server can provide participation functionality for an associated PTT client. In these or other cases, the PTT server may be in the same service domain as the associated PTT client. An example of a service domain can be a network or a portion of a network. For example, the PTT server can be an application server in the home core network of the PTT client. The PTT server can access the configuration and settings of the associated PTT client. The PTT server can also perform media replication functionality, traffic optimization functionality, or a combination thereof for the associated PTT client.

In some cases, a PTT server can provide control functions for a group call. In these or other cases, the PTT server can act as the host for the group call. The PTT server can perform media burst control arbitration functions, such as media burst control or floor control functions, to receive and arbitrate requests to send media in the group call. The PTT server can also perform media replication functions, traffic optimization functions, or a combination thereof for the group call.

In some cases, the PTT servers that perform the participation function and the control function can be collocated in the same entity, such as the first PTT server 102 and the second PTT server 112 shown in FIG1 . Alternatively, the PTT servers that perform the participation function and the control function can be located in different entities in the network architecture. In some cases, as shown in the figure, the first PTT server 102 and the second PTT server 112 can be located in the same wireless network. Alternatively, the first PTT server 102 and the second PTT server 112 can be located in different wireless networks.

In some cases, the PTT server and PTT client can be implemented according to the PTT over Cellular (PoC) or Push to Public Safety (PCPS) standards. The PoC and PCPS standards were developed by the Open Mobile Alliance (OMA) to provide PTT services over Internet Protocol (IP)-based cellular networks. In some cases, the PTT server and PTT client can be implemented according to the Mission Critical PTT (MCPTT) standard developed by 3GPP.

In operation, first PTT server 102 receives a request to invite UEs in second group 114. The request may include an identifier for second group 114. First PTT server 102 sends a first invite message 112 to a second PTT server. The first invite message may include an identifier for second group 114. In response to the first invite message, first PTT server 102 receives a response message. The response message may indicate that second group 114 has an active group call. First PTT server 102 sends a second invite message to at least one of UEs 116a-b to invite at least one of UEs 116a-b to a merged PTT group call. The second invite message may indicate that the merged PTT group call replaces or suspends the second active group call. First PTT server 102 may host the merged PTT group call, which may be participated in by UEs 106a-c and UEs 116a-b. Figures 2-12 and the associated description provide additional details of these embodiments.

Turning to the general description of elements, a UE may be referred to as a mobile electronic device, user equipment, mobile station, subscriber station, portable electronic device, mobile communication device, wireless modem, PTT dispatch console, or wireless terminal. Examples of UEs (e.g., UEs 106a-c and UEs 116a-b) may include cellular phones, personal digital assistants (PDAs), smart phones, PTT dispatch consoles, laptop computers, tablet personal computers (PCs), pagers, portable computers, portable gaming devices, wearable electronic devices, or other mobile communication devices having components for transmitting voice or data via a wireless communication network. The wireless communication network may include a wireless link on at least one of a licensed spectrum and an unlicensed spectrum.

Other examples of UE include mobile and fixed electronic devices. A UE may include a mobile equipment (ME) device and a removable memory module, such as a universal integrated circuit card (UICC) including a subscriber identity module (SIM) application, a universal subscriber identity module (USIM) application, or a removable user identity module (R-UIM) application. The term "UE" may also refer to any hardware or software component that can terminate a user's communication session. Additionally, the terms "user equipment," "UE," "user equipment device," "user agent," "UA," "user device," and "mobile device" may be used synonymously herein.

The wireless communication network 110 may include one or more radio access networks (RANs), other access networks such as fixed Ethernet or IEEE 802.11 WLAN, a core network (CN), and external networks. The RAN may include one or more radio access technologies. In some embodiments, the radio access technology may be Global System for Mobile Communications (GSM), Interim Standard 95 (IS-95), Universal Mobile Telecommunications System (UMTS), CDMA2000 (Code Division Multiple Access), Evolved Universal Mobile Telecommunications System (UMTS), Long Term Evolution (LTE), or Advanced LTE. In some cases, the core network may be an Evolved Packet Core (EPC).

The RAN is the part of a wireless telecommunications system that implements radio access technologies such as UMTS, CDMA2000, 3GPP LTE, and 3GPP LTE-A. In many applications, the RAN includes at least one base station. A base station can be a radio base station that controls all or at least some radio-related functions in the fixed part of the system. A base station can provide a radio interface within its coverage area or a cell through which UEs communicate. Base stations can be distributed throughout a cellular network to provide wide-area coverage. A base station communicates directly with one or more UEs, other base stations, and one or more core network nodes.

Although the elements of FIG1 are shown as including various component parts, portions or modules that implement various features and functions, these elements may also appropriately replace and include multiple sub-modules, third-party services, components, libraries, etc. In addition, the features and functions of various components may be appropriately combined into fewer components.

FIG10 illustrates an example ad hoc PTT group call. A system 1000 for an ad hoc PTT group call may involve a PTT client 1002 acting as the group call initiator, multiple PTT clients 1004a-c that will participate in the group call, and a PTT server 1006. The group call initiator 1002 may send an invite message to the PTT server 1006 to initiate the group call. The invite message may include a list of PTT clients to be invited to the group call. The PTT server 1006 then sends invite requests 1008a-c to the PTT clients 1004a-c to form a group call 1010.

FIG11 illustrates an example pre-arranged PTT group call. A system 1100 for a pre-arranged PTT group call may involve a PTT server 1104, a PTT client 1106 acting as the group call initiator, and a plurality of PTT clients 1108 a-c that will participate in the group call. A list of PTT clients 1102 of the pre-arranged group is pre-provisioned in the PTT server 1104. The group call initiator 1106 may send an invitation message to the uniform resource indicator (URI) of the group. The PTT server 1104 hosting the group then sends an invitation message to the PTT clients 1108 a-c in the pre-arranged group to form a group call 1112.

FIG12 illustrates an example chat PTT group call. A system 1200 for a chat PTT group call may involve a PTT server 1204, a PTT client 1206 acting as the group call initiator, and multiple PTT clients 1208a-c that will participate in the group call. In a restricted chat PTT group call, a list of PTT clients 1202 is pre-provisioned in the PTT server 1204. A PTT client wishing to join the group call sends an invite message or dial-in message 1210a-c to the URI for the group to form a group call 1212. In a restricted chat PTT group call, the PTT server 1204 hosting the group checks whether the requesting PTT client is in the pre-provisioned list. In an unrestricted chat PTT group call, there is no pre-provisioned list, and any PTT client can join. These long-lived, semi-permanent chat group calls are likely a common type of group call used by public safety agencies.

FIG2 is a data flow diagram illustrating an example process 200 for merging active group calls, according to an embodiment. The data flow diagram includes a PTT control server X1 202. PTT control server X1 202 represents an application, a collection of applications, software, a software module, hardware, or a combination thereof that can be configured to provide control functionality for an active group call (e.g., active group call X1, as shown in FIG2 ). In some cases, a group of PTT clients (e.g., group X1) can participate in active group call X1. For example, as shown, group X1 can include PTT client A 206. The data flow diagram also includes a PTT participating server A 204. PTT participating server A 204 represents an application, a collection of applications, software, a software module, hardware, or a combination thereof that can be configured to provide participation functionality for PTT client A 206. In some cases, PTT control server X1 202 and PTT participating server A 204 can be implemented on the same PTT server. In these or other cases, the messages between PTT control server X1 202 and PTT participating server A 204 shown in the data flow diagram can be omitted.

The data flow diagram also includes a PTT control server X2 212 that provides control functionality for the active group call X2. In some cases, another group of PTT clients (e.g., group X2) can participate in the active group call X2. For example, as shown, group X2 can include PTT client B1 216 and PTT client B2 218. The data flow diagram also includes a PTT participating server B 214 that provides participation functionality for PTT client B1 216 and PTT client B2 218. In some cases, PTT control server X2 212 and PTT participating server B 214 can be implemented on the same PTT server. In these or other cases, the messages between PTT control server X2 212 and PTT participating server B 214 shown in the data flow diagram can be omitted.

As shown in Figure 2, prior to step 1, both active group calls X1 and X2 are in progress. At step 1, PTT client A 206 sends a request to PTT participating server A 204 to invite group X2 to active group call X1. In some cases, the request may be a referral request. In some cases, the request may include an identifier for group X2. Examples of identifiers may include a uniform resource indicator (URI) or any other group identity indicator. In some cases, the URI may be a string used to identify group X2. In some cases, the identifier may be included in the Refer-To header field of the referral request. In some cases, the request may be sent by an authorized PTT client in group X1 (e.g., PTT client A 206 shown). Alternatively, or in combination, the request may be sent by a scheduler not in group X1. Alternatively, or in combination, the request may be sent by a group management server upon creation of a merged group of X1 and X2 in the group management server, in order to merge the group calls of X1 and X2.

At step 2, PTT participating server A 204 forwards the request to PTT controlling server X1 202. At step 3, PTT controlling server X1 202 sends an OK response to PTT participating server A 204, which forwards the response to PTT client A 706 at step 4. In some cases, the OK response indicates that PTT controlling server X1 202 has received the request.

At step 5, PTT control server X1 202 sends an invitation message to PTT control server X2 212. In some cases, the invitation message may include an identifier for group X2. In response to the invitation message, at step 6, PTT control server X2 212 sends a response message to PTT control server X1 202. In some cases, the response message may be a 4xx message, such as a 403 message. In some cases, the response message may include an indication that group X2 is currently in an active group call. In some cases, the indication that group X2 is currently in an active group call may be encoded using Extensible Markup Language (XML). Alternatively, or in combination, the indication may be encoded in one or more existing or new header fields in the response message. In some cases, the response message may also include a list of PTT clients in group X2. In some cases, the list of PTT clients may be encoded using Extensible Markup Language (XML). Alternatively, or in combination, the list of PTT clients may be encoded in one or more existing or new header fields in the response message.

In some cases, some PTT clients in group X2 are currently participating in the active group call X2, while some other PTT clients in group X2 are authorized to participate but are not currently participating in the currently active group call X2. In some cases, some PTT clients in group X2 are affiliated with the group but are not currently participating in the active group call X2. In these or other cases, the response message may include a list of PTT clients in group X2 and one or more indications indicating whether a PTT client in group X2 is currently participating in group call X2 or is currently affiliated with group X2. Thus, PTT clients currently participating in or affiliated with the active group call X2 may be invited to the merged call. PTT clients in group X2 that are not participating in group call X2 may be authorized to join the merged call later. This approach enables the PTT control server X1 202 to merge active participants or affiliated members of group calls X1 and X2 without having to invite all authorized members of groups X1 and X2.

Alternatively, or in combination, the PTT control server X1 202 can use a subscription notification procedure to obtain information about members of group X2 currently participating in the active group call X2. For example, the PTT control server X1 202 can send a subscription request to the PTT control server X2 212 requesting data about PTT clients in group X2. The subscription request can include an identifier for group X2. FIG3 illustrates an example subscription request 300 according to an embodiment. As shown in FIG3 , the subscription request 300 can include an event identity (ID) field. The event ID field can indicate that the event is group_members, which notifies the PTT control server X2 212 of information about the group members in the requested group.

In response to the subscription request, the PTT control server X2 212 may send a notification message to the PTT control server X1 202. The notification message may indicate the PTT clients currently participating in the active group call X2 and the PTT clients that are authorized but have not yet joined. FIG4 illustrates an example notification message 400 according to an embodiment. As shown in FIG4 , the notification message 400 may include a list of group members in the group X2. For each group member, the notification message 400 may include the member's identity, such as the member's Session Initiation Protocol (SIP) URI and a status indicator. For members currently participating in the group call X2, the status indicator may be set to "active." For members not currently participating in the group call X2, the status indicator may be set to "inactive." For members who are affiliated but not currently participating in the group call X2, the status indicator may be set to "affiliated."

In some cases, the notification message may also indicate information about the bearer used by members of group X2 to participate in the active group call X2. FIG5 illustrates an example portion of a notification message 500 indicating bearer information, according to an embodiment. As shown in FIG5 , the notification message 500 may include a temporary multicast group identity (TMGI) for each member of group X2 that is actively participating in group call X2. The TMGI may indicate the Multimedia Broadcast/Multicast Service (MBMS) bearer used by the active members in group call X2. In some cases, the subscription notification procedure may be combined with steps 15-18 discussed below.

At steps 7 and 9, the PTT control server X1 202 invites the PTT clients in group X2 that are actively participating in the active group call X2 to join the merged call. For example, at step 7, the PTT control server X1 202 sends an invite message to the PTT participating server B 214, which forwards the invite message to the PTT client B1 216 at step 8. Similarly, at step 9, the PTT control server X1 202 sends an invite message to the PTT participating server B 214, which forwards the invite message to the PTT client B 221 at step 10. At steps 7 and 9, the invite message contains the necessary identifiers for the PTT clients to join the merged PTT call.

In some cases, the invite message sent at step 5 may indicate that if the group is in an active group call, the PTT control server X2 212 should invite the active members of the group call X2. In this case, the invite messages at steps 7 and 9 are sent by the PTT control server X2 212 rather than the PTT control server X1 202. In this case, the invite messages at steps 5, 7, and 9 contain the necessary identifiers for the PTT client to join the merged PTT call.

In some cases, the invitation message may indicate that the invitation is for replacing or suspending the merged call of active group call X2. If the merged call replaces the active group call X2, the active group call X2 may be terminated when the PTT clients participating in the active group call X2 have joined the merged call. If the merged call suspends the active group call X2, the active group call X2 may be put on hold when the PTT clients participating in the active group call X2 join the merged call. When the merged call is terminated, the active group call X2 may be resumed. In some cases, the indication that the merged call replaces or suspends the active group call X2 may be encoded using Extensible Markup Language (XML). Alternatively, or in combination, the indication may be encoded in one or more existing or new header fields in the response message.

In some cases, the invite message may also indicate whether a unicast bearer or a multicast bearer is to be used for the merged call.If a multicast bearer is to be used, the invite message may include the TMGI associated with the multicast bearer to be used.

At step 11, PTT client B1 216 sends an OK message to PTT participating server B 214, which forwards the OK message to PTT controlling server X1 202 at step 12. Similarly, at step 13, PTT client B2 218 sends an OK message to PTT participating server B 214, which forwards the OK message to PTT controlling server X1 202 at step 14. The OK message may indicate that the PTT client has received the invitation message.

At step 15, PTT control server X1 202 may send a subscription request to PTT control server X2 212 to request metadata information for group X2. The subscription request may include an identifier for group X2. At step 16, PTT control server X2 212 sends an OK message to PTT control server X1 202 to indicate receipt of the subscription request. At step 17, PTT control server X2 212 sends a notification message to PTT control server X1 202. The notification message may include metadata information for group X2. In some cases, the metadata information may include information regarding pending requests to transmit media stored in PTT control server X2 212 in the active group call X2. For example, one or more members may have requested to transmit media in the active group call X2 before PTT control server X2 212 received the invitation message in step 5. By receiving information about pending requests, such as timestamps, queue positions, and priorities, PTT control server X1 can place these requests in a queue appropriately ordered with pending requests in the active group call X1 and process them accordingly.

FIG6 illustrates an example portion of a notification message 600 indicating a pending request, according to an embodiment. As shown in FIG6 , notification message 600 may indicate PTT floor request queue information for the pending request. The queue information may include the queue position, priority, timestamp, or a combination thereof of the pending request. In some cases, a privilege level may be used to indicate priority.

In some cases, as discussed above, the notification message may also indicate the bearer information used by the PTT client for the active group call X2. For example, the notification message may include the TMGI of the MBMS bearer used by the active members participating in the active group call X2.

At step 19, PTT client B1 216 sends an update to PTT participating server B 214, which forwards the update to PTT control server X2 212 at step 20. In some cases, the update may instruct PTT client B1 216 to place its session with active group call X2 on hold. Alternatively, or in combination, an invite message may be used to indicate that its session with group call X2 is on hold. In some cases, for example, active group call X2 may be replaced by a merged call. In these or other cases, PTT client B1 216 may send a goodbye message to indicate that its session with active group call X2 will be terminated. At step 21, PTT control server X2 212 sends an OK response to PTT participating server B 214, which forwards the OK response to PTT client B1 216 at step 22. The OK response indicates receipt of the update. Similarly, at step 23, the PTT client B2 218 sends an update to the PTT participating server B 214, which forwards the update to the PTT controlling server X2 212 at step 24. Thus, when the PTT controlling server X2 212 receives updates, invitations, or goodbyes from all active members participating in the active group call X2, the PTT controlling server X2 212 may place the active group call X2 on hold or terminate the active group call X2.

At step 25, PTT client A 206 may send a media burst request message to PTT participating server A 204, which forwards the media burst request message to PTT control server X1 202. The media burst request message may be used to request the transmission of media in the merged group call. In some cases, the media burst request message may be sent using a Real-Time Control Protocol (RTCP) application (APP) packet. Alternatively, or in combination, the media burst request message may be sent using a binary floor control protocol (BFCP).

At step 27, PTT control server X1 202 may determine that the request to send media is authorized. At step 28, PTT control server X1 202 may send a media burst grant message to PTT participating server A 204, which forwards the media to PTT client A 206 at step 28. The media burst grant message may be sent using RTCP APP packets or BFCP. PTT control server X1 202 may also send a media burst get message to PTT client B1 216 and PTT client B2 218 to indicate that the media is being obtained by another PTT client in the merged group call. The media burst get message may be sent using RTCP APP packets or BFCP. Accordingly, PTT client A 206 may send the media to PTT control server X1 202, which forwards the media to the other members of the merged call, including PTT client B1 216 and PTT client B2 218.

In some cases, an invite message may be broadcast to multiple members of active group call X2 rather than individually inviting the members of active group call X2 to the merged call. FIG7 is a data flow diagram illustrating an example process 700 for merging active group calls using a broadcast message, according to an embodiment. The data flow diagram includes a PTT control server X1 702 hosting active group call X1 and a PTT control server X2 712 hosting active group call X2. The data flow diagram also includes a PTT participating server A 704 associated with a PTT client A 706 participating in active group call X1. In some cases, PTT control server X1 702 and PTT participating server A 704 may be implemented on the same PTT server. The data flow diagram also includes a PTT participating server B 714 associated with a PTT client B1 716 and a PTT client B2 718. PTT client B1 716 and PTT client B2 718 participate in active group call X2. In some cases, the PTT control server X2 712 and the PTT participating server B 714 may be implemented on the same PTT server.

As shown, active group call X1 is ongoing at step 1, and active group call X2 is ongoing at step 2. At step 3, PTT client A 706 sends a request to PTT participating server A 704 to invite group X2 to active group call X1. In some cases, the request may be a referral request. In some cases, the request may include an identifier for group X2. Examples of identifiers may include a uniform resource indicator (URI) or any other group identity indicator. In some cases, the URI may be a string used to identify group X2. In some cases, the identifier may be included in the Refer-To header field of the referral request. Alternatively, or in combination, the request may be sent by the group management server based on creating a merged group of X1 and X2 in the group management server to merge the group calls of X1 and X2.

At step 4, the PTT participating server A 704 forwards the request to the PTT controlling server X1 702. At step 5, the PTT controlling server X1 702 sends an OK response to the PTT participating server A 704, which forwards it to the PTT client A 706 at step 4.

At step 7, PTT control server X1 702 sends an invitation message to PTT control server X2 712. In some cases, the invitation message may include an identifier for group X2. In response to the invitation message, at step 8, PTT control server X2 712 sends a response message to PTT control server X1 702. In some cases, the response message may include an indication that group X2 is currently in an active group call. In some cases, the response message may also include a list of PTT clients in group X2 and information indicating whether each PTT client is currently active on group call X2. In some cases, the response message may include an indication that group X2 is currently in an active group call. In some cases, the indication that group X2 is currently in an active group call may be encoded using Extensible Markup Language (XML). Alternatively, or in combination, the indication may be encoded in one or more existing or new header fields in the response message. In some cases, the response message may also include a list of PTT clients in group X2. In some cases, the list of PTT clients may be encoded using Extensible Markup Language (XML). Alternatively, or in combination, the list of PTT clients may be encoded in one or more existing or new header fields in the response message.

In some cases, some PTT clients in group X2 are currently participating in the active group call X2, while some other PTT clients in group X2 are authorized to participate but are not currently participating in the currently active group call X2. In some cases, some PTT clients in group X2 are affiliated with the group but are not currently participating in the active group call X2. In these or other cases, the response message may include a list of PTT clients in group X2 and one or more indications indicating whether a PTT client in group X2 is currently participating in group call X2 or is currently affiliated with group X2. Thus, PTT clients currently participating in or affiliated with the active group call X2 may be invited to the merged call. PTT clients in group X2 that are not participating in group call X2 may be authorized to join the merged call later. This method enables the PTT control server X1 702 to merge the active participants or affiliated members of group calls X1 and X2 without inviting all authorized members of groups X1 and X2.

The invitation message at step 7 and step 9 contains the necessary identifier for the PTT client to join the merged PTT call.

In some cases, the invite message sent at step 7 may indicate that if the group is in an active group call, the PTT control server X2 712 should invite the active members of the group call X2. In other cases, the invite message sent at step 7 does not indicate that the PTT control server X2 712 should invite the active members of the group call X2. In this case, the invite message at step 9 is sent by the PTT control server X1 702 rather than the PTT control server X2 712.

At step 9, the PTT control server X2 712 broadcasts an invite message to all active members of group X2. The invite message may be a message configured to be sent via a multicast bearer. For example, the invite message may be a non-SIP message. In some cases, the invite message may include information about the active group call X1 that members of group X2 can join for the merged call. For example, the invite message may include an identifier for group X1, such as a URI for group X1. In some cases, the invite message may indicate information about the bearer used for the active group call X1. For example, the invite message may include one or more TMGIs for the active bearers used in the active group call X1. In some cases, the invite message may also include Proximity-Based Services (ProSe) information for the active group call X1. Alternatively, or in combination, the invite message may be sent using a modified floor control message. The modified floor control message may include information about the new group call for the merged group call. For example, the invite message may include an identifier for the new group, a TMGI, or a combination thereof. In some cases, the invite message may include authentication information that can be used to authenticate the PTT client in group X2. For example, the authentication information may be an encrypted token, a P-assertion URI, or a combination thereof.

At step 10, PTT client B1 716 requests to join active group call X1 for the merged call. In some cases, PTT client B1 716 sends authentication response information to PTT control server X1 702. The authentication response information may be associated with the authentication information in the broadcast invite message. For example, the authentication response information may be based on a decrypted token. PTT control server X1 702 may authenticate PTT client B1 716 based on the authentication information and authorize PTT client B1 716 to join the merged call. In some cases, PTT control server X1 702 may use the authentication response information and member list information received in step 8 to authenticate PTT client B1 716. Alternatively, or in combination, PTT client B1 716 may receive an authentication challenge. The authentication challenge may include the contact URI identity of active group call X2. If PTT client B1 716 does not successfully pass the authentication challenge, PTT control server X1 702 may determine to change the group participation characteristics of the PTT client, such as instructing the PTT client to leave the group call, instructing the PTT client not to send data, or not receive/send data.

Similarly, at step 11, PTT client B2 718 requests to join active group call X1 for a merged call.

At step 12, PTT client B1 716 sends an update message to PTT participating server B 714, which forwards the update message to PTT control server X2 712 at step 13. The update message may indicate that PTT client B1 716 will not participate in group call X2. For example, the update message may indicate that PTT client B1 716 will not receive, transmit, or a combination thereof in group call X2. Similarly, at step 14, PTT client B2 718 sends an update message to PTT participating server B 714, which forwards the update message to PTT control server X2 712 at step 15. In some cases, PTT control server X2 712 may keep group call X2 active until all active members cease participating in group call X2. As previously discussed, in some cases, PTT control server X2 712 may terminate group call X2. Alternatively, the PTT control server X2 712 may place the group call X2 on hold.

8 is a block diagram 800 of an exemplary computer that can be used to merge active group calls according to an embodiment. The computer 802 shown is intended to encompass any computing device, such as a server, desktop computer, laptop/notebook computer, wireless data port, smart phone, personal data assistant (PDA), tablet computing device, one or more processors within these devices, and/or any other suitable processing device, including physical and/or virtual instances of computing devices. In addition, the computer 802 can include a computer that includes input devices such as a keypad, keyboard, touch screen, microphone, voice recognition device, other devices that can accept user information, and/or output devices that transmit information associated with the operation of the computer 802 (including digital data, visual and/or audio information, or GUI).

The computer 802 can function as a client, a network component, a server, a database or other persistent device, and/or any other component of the system 100. For example, the computer 802 can be used to implement one or more functions of a PTT server or a PTT client. The computer 802 is shown communicatively coupled to the network 830. In some embodiments, one or more components of the computer 802 can be configured to operate within a cloud computing-based environment.

At a high level, the computer 802 is an electronic computing device operable to receive, send, process, store, or manage data and information associated with the system 100. According to some embodiments, the computer 802 may also include or be communicatively coupled with an application server, an email server, a web server, a cache server, a streaming data server, a business intelligence (BI) server, and/or other servers.

Computer 802 can receive requests from client applications (e.g., executed on another computer 802) over network 830 and respond to the received requests by processing the requests in an appropriate software application. Requests can also be sent to computer 802 from internal users (e.g., from a command console or through another appropriate access method), external or third parties, other automated applications, and any other appropriate entity, person, system, or computer.

Each of the components of computer 802 can communicate using system bus 803. In some embodiments, any and/or all components (both hardware and/or software) of computer 802 can interface with each other and/or interface with interfaces 804 on system bus 803 using application programming interfaces (APIs) 812 and/or service layers 813. API 812 can include specifications for routines, data structures, and object classes. API 812 can be computer language independent or computer language dependent and can refer to a complete interface, a single function, or even a set of APIs. Service layer 813 provides software services to computer 802 and/or system 100. The functions of computer 802 can be accessed by all service consumers using the service layer. Software services such as those provided by service layer 813 provide reusable, defined business functions through defined interfaces. For example, the interface can be software written in JAVA, C++, or other suitable languages that provide data in Extensible Markup Language (XML) format or other suitable formats. Although shown as an integrated component of the computer 802, alternative implementations may show the API 812 and/or the services layer 813 as separate components associated with the computer 802 and/or other components of the system 100. Furthermore, any or all portions of the API 812 and/or services layer 813 may be implemented as a subclass or submodule of another software module, enterprise application, or hardware module without departing from the scope of the present disclosure.

The computer 802 includes an interface 804. Although shown as a single interface 804 in FIG. 8 , two or more interfaces 804 may be used depending on the specific needs, desires, or specific implementation of the computer 802 and/or system 100. The computer 802 uses the interface 804 to communicate with other systems in a distributed environment, including within the system 100—connected to a network 830 (whether illustrated or not). Typically, the interface 804 includes logic encoded in software and/or hardware in an appropriate combination and operable to communicate with the network 830. More specifically, the interface 804 may include software supporting one or more communication protocols associated with the communication, such that the network 830 or the hardware of the interface is operable to transmit physical signals within and external to the system 100 shown.

Computer 802 includes a processor 805. Although shown as a single processor 805 in FIG8 , two or more processors may be used depending on the particular needs, desires, or particular implementation of computer 802 and/or system 100. Generally, processor 805 executes instructions and manipulates data to perform operations of computer 802. Specifically, processor 805 performs the functions required to merge active group calls.

The computer 802 also includes a memory 806 that stores data for the computer 802 and/or other components of the system 100. Although shown as a single memory 806 in Figure 8, two or more memories may be used depending on the particular needs, desires, or implementation of the computer 802 and/or system 100. Although the memory 806 is shown as an integral component of the computer 802, in alternative implementations, the memory 806 may be external to the computer 802 and/or system 100.

Application 807 is an algorithmic software engine that provides functionality based on the specific needs, desires, or specific implementation of computer 802 and/or system 100, particularly functionality required for merging active group calls. For example, application 807 may be used as one or more of the components/applications described in Figures 1-12. Furthermore, although shown as a single application 807, application 807 may be implemented as multiple applications 807 on computer 802. Furthermore, although shown as integral to computer 802, in alternative implementations, application 807 may be external to computer 802 and/or system 100.

There can be any number of computers 802 associated with the system 100 (or external to the system 100) and communicating over the network 830. Furthermore, the terms "client," "user," and other appropriate terms may be used interchangeably without departing from the scope of this disclosure. Furthermore, this disclosure contemplates that many users may use one computer 802, or that one user may use multiple computers 802.

FIG9 is a flow diagram illustrating an example method 900 for merging active group calls. Method 900 may begin at block 902, where a first push-to-talk (PTT) server hosts a first active group call. A first group of PTT clients participates in the first active group call. At block 904, the first PTT server receives a request to invite a second group of PTT clients. The request includes an identifier for the second group of PTT clients.

At block 906, the first PTT server sends a first invite message to the second PTT server. The second PTT server hosts the second active group call. The first invite message includes an identifier for the second group of PTT clients. The second group of PTT clients participate in the second active group call. At block 908, the first PTT server receives a response message in response to the first invite message. The response message indicates that the second group of PTT clients are participating in the second active group call.

At block 910, the first PTT server sends a second invite message. The second invite message invites at least one PTT client in the second group of PTT clients to the merged PTT group call. The second invite message indicates that the merged PTT group call replaces or suspends the second active group call. In some cases, the second invite message is sent via a Multimedia Broadcast/Multicast Service (MBMS) channel.

At block 912, the first PTT server sends a subscription request to the second PTT server. At block 914, in response to the subscription request, the first PTT server receives a notification message. The notification message includes metadata for the second group of PTT clients. In some cases, the metadata indicates a request to send media. A pending request is received at the second PTT server before the first invite message. In some cases, the metadata indicates at least one of a timestamp, a queue position, or a priority of the pending request. In some cases, the metadata indicates a multimedia broadcast/multicast service (MBMS) bearer used by at least one PTT client in the second group of PTT clients for the second active group call. At block 916, the first PTT server hosts a merged PTT group call participated in by the first group of PTT clients and the second group of PTT clients.

Although operations are described in a particular order in the accompanying drawings, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, in order to achieve the desired results. In some cases, multitasking and parallel processing may be utilized. Furthermore, the separation of various system components in the above-described embodiments should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems may generally be integrated together in a single software product or packaged into multiple software products.

In addition, the techniques, systems, subsystems and methods described and shown as discrete or separated in various embodiments can be combined or integrated with other systems, modules, techniques or methods. Other items shown or discussed as being coupled to each other or directly coupled or communicating with each other can be indirectly coupled or indirectly coupled or communicated through some interface, device or intermediate component, whether electrically, mechanically or otherwise. Other examples of variations, substitutions and modifications can be determined and made by those skilled in the art.

While the foregoing detailed description has shown, described, and pointed out the basic novel features of the present disclosure as applied to various embodiments, it will be understood that various omissions, substitutions, and changes in the form and details of the systems shown may be made by those skilled in the art. In addition, the order of the method steps is not implied by the order in which they appear in the claims.

Claims (20)

1. A method for merging activity group calls, comprising: The first PTT server manages the first active group call, in which the first group of PTT clients participate in the first active group call; The first PTT server receives a request to invite a second group of PTT clients, wherein the request includes the identifier of the second group of PTT clients; A first invitation message is sent from the first PTT server to the second PTT server, wherein the first invitation message includes the identifier of the second group of PTT clients, the second PTT server manages the second active group call, and the second group of PTT clients participate in the second active group call; In response to the first invitation message, a response message is received at the first PTT server from the second PTT server, wherein the response message indicates that the second group of PTT clients is participating in the second active group call; and The first PTT server manages the merged PTT group calls, wherein the first group of PTT clients and the second group of PTT clients participate in the merged PTT group calls. 2. The method of claim 1, further comprising sending a second invitation message, wherein the second invitation message invites at least one PTT client from the second group of PTT clients to the merged PTT group call, and the second invitation message instructs the merged PTT group call to replace or suspend the second active group call. 3. The method according to claim 2, wherein the second invitation message is sent via a Multimedia Broadcast/Multicast Service (MBMS) channel. 4. The method according to claim 1, further comprising: Send a subscription request to the second PTT server; and In response to the subscription request, a notification message is received, wherein the notification message includes metadata of the second group of PTT clients. 5. The method of claim 4, wherein the metadata indicates a pending request for sending media, wherein the pending request is received at the second PTT server prior to the first invitation message. 6. The method of claim 5, wherein the metadata indicates at least one of the timestamp, queue position, or priority of the pending request. 7. The method of claim 4, wherein the metadata indicates the multimedia broadcast/multicast service (MBMS) carrier used by at least one PTT client in the second group of PTT clients for the second active group call. 8. An apparatus for merging active group calls, comprising: Memory; and At least one hardware processor, communicatively coupled to the memory, is configured to: The first PTT server manages the first active group call, in which the first group of PTT clients participate in the first active group call; The first PTT server receives a request to invite a second group of PTT clients, wherein the request includes the identifier of the second group of PTT clients; A first invitation message is sent from the first PTT server to the second PTT server, wherein the first invitation message includes the identifier of the second group of PTT clients, the second PTT server manages the second active group call, and the second group of PTT clients participate in the second active group call; In response to the first invitation message, a response message is received at the first PTT server from the second PTT server, wherein the response message indicates that the second group of PTT clients is participating in the second active group call; and The first PTT server manages the merged PTT group calls, wherein the first group of PTT clients and the second group of PTT clients participate in the merged PTT group calls. 9. The device of claim 8, wherein the at least one hardware processor is further configured to send a second invitation message, wherein the second invitation message invites at least one PTT client from the second group of PTT clients to the merged PTT group call, and the second invitation message instructs the merged PTT group call to replace or suspend the second active group call. 10. The device of claim 9, wherein the second invitation message is sent via a Multimedia Broadcast/Multicast Service (MBMS) channel. 11. The device of claim 8, wherein the at least one hardware processor is further configured to: Send a subscription request to the second PTT server; and In response to the subscription request, a notification message is received, wherein the notification message includes metadata of the second group of PTT clients. 12. The device of claim 11, wherein the metadata indicates a pending request for sending media, wherein the pending request is received at the second PTT server prior to the first invitation message. 13. The device of claim 12, wherein the metadata indicates at least one of the timestamp, queue position, or priority of the pending request. 14. The device of claim 11, wherein the metadata indicates the multimedia broadcast/multicast service (MBMS) carrier used by at least one PTT client in the second group of PTT clients for the second active group call. 15. A tangible, non-transitory, computer-readable medium containing instructions that, when executed, cause a computing device to perform operations, the operations including: The first PTT server manages the first active group call, in which the first group of PTT clients participate in the first active group call; The first PTT server receives a request to invite a second group of PTT clients, wherein the request includes the identifier of the second group of PTT clients; A first invitation message is sent from the first PTT server to the second PTT server, wherein the first invitation message includes the identifier of the second group of PTT clients, the second PTT server manages the second active group call, and the second group of PTT clients participate in the second active group call; In response to the first invitation message, a response message is received at the first PTT server from the second PTT server, wherein the response message indicates that the second group of PTT clients is participating in the second active group call; and The first PTT server manages the merged PTT group calls, wherein the first group of PTT clients and the second group of PTT clients participate in the merged PTT group calls. 16. The tangible non-transitory computer-readable medium of claim 15, wherein the operation further comprises sending a second invitation message, wherein the second invitation message invites at least one PTT client from the second group of PTT clients to the merged PTT group call and the second invitation message instructs the merged PTT group call to replace or suspend the second active group call. 17. The tangible non-transitory computer-readable medium of claim 16, wherein the second invitation message is transmitted via a multimedia broadcast/multicast service (MBMS) channel. 18. The tangible non-transitory computer-readable medium of claim 15, wherein the operation further comprises: Send a subscription request to the second PTT server; and In response to the subscription request, a notification message is received, wherein the notification message includes metadata of the second group of PTT clients. 19. The tangible non-transitory computer-readable medium of claim 18, wherein the metadata indicates a pending request for the transmission medium, wherein the pending request is received at the second PTT server prior to the first invitation message. 20. The tangible non-transitory computer-readable medium of claim 19, wherein the metadata indicates at least one of a timestamp, queue position, or priority of the pending request.