System and method for push-to-talk (PTT) in high latency networks

1. A method comprising:

accessing, by a push to talk (PTT) server, a PTT session with a PTT client operating in a first network;

detecting, by the PTT server, a transition by the PTT client from the first network to a second network, the second network having a lower throughput or a higher latency than the first network; and

adapting, by the PTT server, one or more parameters of a plurality of communication protocols in response to detecting the transition by the PTT client from the first network to the second network, the communication protocols being host layer protocols used by the PTT server to communicate with the PTT client, wherein the adapting the parameters of the communication protocols comprises changing, by the PTT server, the transport protocol to a connectionless protocol, wherein the parameters of the communication protocols include parameters for a media protocol, and wherein the adapting the parameters of the communication protocols comprises:

caching, by the PTT server, header information of voice packets for the PTT session; and

aggregating, by the PTT server, the voice packets for the PTT session in data units transmitted over the second network; and

wherein the parameters for the media protocol include codec parameters, and wherein the adapting the parameters of the communication protocols further comprises:

determining, by the PTT server, a call session quality indicator (CSQI) of the PTT client for the PTT session; and

decreasing, by the PTT server, a bitrate of the codec parameters in response to the CSQI of the PTT client decreasing.

2. The method of claim 1 , wherein the adapting the parameters of the communication protocols further comprises:

disabling, by the PTT server, encryption for the transport protocol.

3. The method of claim 1 , wherein the parameters of the communication protocols include parameters for a signaling protocol of the communication protocols, and wherein the adapting the parameters of the communication protocols comprises:

increasing, by the PTT server, timeout values for the signaling protocol; and

increasing, by the PTT server, retransmission times for floor control messages of the PTT session exponentially for each retransmission of the floor control messages.

4. The method of claim 1 , further comprising:

reverting, by the PTT server, the one or more parameters of the plurality of communication protocols in response to detecting a transition by the PTT client from the second network to a third network having a higher throughput or a lower latency than the second network.

5. The method of claim 1 , wherein the adapting the parameters of the communication protocols comprises:

suppressing, by the PTT server, transmission of audio for the PTT session to the PTT client in response to a total voice energy of the audio for the PTT session being below a predefined threshold.

6. The method of claim 1 , wherein the adapting the parameters of the communication protocols further comprises:

deferring, by the PTT server, synchronization of contact information, group information, presence information, and location information with the PTT client, the synchronization deferred until the PTT client transitions to a third network having a higher throughput or a lower latency than the second network.

7. A push-to-talk (PTT) server comprising:

a transceiver configured to communicate with a PTT client;

a memory configured to store a plurality of first parameters; and

an electronic processor configured to:

access a PTT session with the PTT client operating in a first network;

detect a transition by the PTT client from the first network to a second network, the second network having a lower throughput or a higher latency than the first network; and

adapt one or more parameters of a plurality of communication protocols according to the first parameters in response to detecting the transition by the PTT client from the first network to the second network, the communication protocols being host layer protocols used by the PTT server to communicate with the PTT client, wherein the electronic processor adapts the parameters of the communication protocols by changing the transport protocol to a connectionless protocol, wherein the parameters of the communication protocols include parameters for a media protocol, and wherein the electronic processor adapts the parameters of the communication protocols by:

caching header information of voice packets for the PTT session; and

aggregating the voice packets for the PTT session in data units transmitted over the second network; and

wherein the parameters for the media protocol include codec parameters, and wherein the electronic processor further adapts the parameters of the communication protocols by:

determining a call session quality indicator (CSQI) of the PTT client for the PTT session; and

decreasing a bitrate of the codec parameters in response to the CSQI of the PTT client decreasing.

8. The PTT server of claim 7 , wherein the electronic processor further adapts the parameters of the communication protocols by:

disabling encryption for the transport protocol.

9. The PTT server of claim 7 , wherein the parameters of the communication protocols include parameters for a signaling protocol of the communication protocols, and wherein the electronic processor adapts the parameters of the communication protocols by:

increasing timeout values for the signaling protocol; and

increasing retransmission times for floor control messages of the PTT session exponentially for each retransmission of the floor control messages.

10. The PTT server of claim 7 , wherein the electronic processor adapts the parameters of the communication protocols by:

deferring, by the PTT server, synchronization of contact information, group information, presence information, and location information with the PTT client, the synchronization deferred until the PTT client transitions to a third network having a higher throughput or a lower latency than the second network.

11. The PTT server of claim 7 , wherein the electronic processor adapts the parameters of the communication protocols by:

suppressing transmission of audio for the PTT session to the PTT client in response to a total voice energy of the audio for the PTT session being below a predefined threshold.

12. The PTT server of claim 7 , wherein the electronic processor is further configured to:

revert the one or more parameters of the plurality of communication protocols in response to detecting a transition by the PTT client from the second network to a third network having a higher throughput or a lower latency than the second network.

13. A method comprising:

accessing, by a push to talk (PTT) server, a PTT session with a PTT client operating in a first network;

receiving, by the PTT server, from the PTT client, an indication that the PTT client has transitioned from the first network to a second network, the second network having a lower throughput or a higher latency than the first network;

deferring, by the PTT server, synchronization of contact information, group information, presence information, and location information with the PTT client until the PTT client transitions to a third network having a higher throughput or a lower latency than the second network;

caching, by the PTT server, header information of voice packets for the PTT session; and

decreasing, by the PTT server, a bitrate of codec parameters for the voice packets in response to a call session quality indicator (CSQI) of the PTT client for the PTT session decreasing.

14. The method of claim 13 , further comprising:

disabling, by the PTT server, encryption for a transport protocol used by the PTT server to communicate with the PTT client in response to determining the second network is a satellite network.