5 Entities

24.3803GPPMission Critical Push To Talk (MCPTT) media plane controlProtocol specificationRelease 18TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

5.1 General

This clause associates the functional entities with the MCPTT roles described in the stage 2 architecture document (see 3GPP TS 23.379 [5]).

5.2 MCPTT client

5.2.1 Introduction

To be compliant with the procedures in the present document, an MCPTT client shall:

1. support the role of an MCPTT client as specified 3GPP TS 23.379 [5];

2. support the on-network MCPTT client role as specified in 3GPP TS 24.379 [2];

3. support the off-network MCPTT client role as specified in 3GPP TS 24.379 [2]; and

4. support media plane security as specified in clause 13.

To be compliant with the on-network procedures in the present document, an MCPTT client shall:

1. provide the role of a floor participant in on-network mode as specified in clause 5.2.2;

2. provide the media mixer function as described in clause 4.2.2 and support the related procedures in clause 6.2;

3. when operating in systems that support MBMS functionality, provide the MBMS interface as described in clause 4.2.2 and support the related MBMS subchannel control procedure as specified in clause 10.3;

4. provide PTT button events towards the on-network floor participant as specified in clause 6.2;

5. provide means (sound, display, etc.) for indications towards the MCPTT user as specified in clause 6.2;

6. support negotiating media plane control channel media level attributes as specified in clause 4.3; and

7. support call setup control over pre-established session as specified in clause 9.2.

To be compliant with the off-network procedures in the present document, an MCPTT client shall:

1. provide the role of a floor participant in off-network mode as specified in clause 5.2.3;

2. support the role of an off-network floor participant as specified in 3GPP TS 23.379 [5] and in the present specification;

3. provide the media mixer function as described in clause 4.2.2 and support the related procedures as specified in clause 7;

4. provide PTT button events towards the off-network floor participant as specified in clause 7; and

5. provide means (sound, display, etc.) for indications towards the MCPTT user as specified in clause 7.

5.2.2 Floor participant in on-network mode

To be compliant with the on-network procedures in the present document, a floor participant in on-network mode shall:

1. support the on-network floor control procedures as defined in 3GPP TS 23.379 [5];

2. support acting as an on-network floor participant as specified in clause 6.2; and

3. support the on-network mode floor control protocol elements as specified in the clause 8.

A floor participant in on-network mode may:

1. support queueing of floor requests as specified in clause 6.2 and clause 4.1.1.2.

5.2.3 Floor participant in off-network mode

To be compliant with the off-network procedures in the present document, a floor participant in off-network mode shall:

1. support off-network floor control procedures as specified in 3GPP TS 23.379 [5];

2. support acting as an off-network floor participant as specified in clause 7;

3. support acting as an off-network floor control server as specified in clause 7; and

4. support the off-network mode floor control protocol elements in clause 8.

A floor participant in off-network mode may:

1. support queueing of floor requests as specified in clause 7 and clause 4.1.1.3.

5.3 Controlling MCPTT function

An MCPTT server providing the controlling MCPTT function shall:

1. support the role of a controlling MCPTT function as specified in 3GPP TS 23.379 [5];

2. support negotiating media plane control channel media level attributes as specified in clause 4.3;

3. provide floor control arbitration logic with an interface to MCPTT clients as described in clause 4.2.1 and support the related procedures as specified in clause 6.3;

4. provided a network media interface as described in clause 4.2.1 and support associated procedures as specified in clause 6.3;

5. provide a media distributor with a floor control interface towards the MCPTT clients as described in clause 4.2.1 and support associated procedures in clause 6.3;

6. support the on-network mode floor control protocol elements as specified in clause 8: and

7. support media plane security as specified in clause 13.

An MCPTT server providing the controlling MCPTT function may:

1. provide a floor request queue as described in clause 4.2.1 and support the related procedures as specified in clause 6.3 and clause 4.3.

5.4 Participating MCPTT function

An MCPTT server providing the participating MCPTT function shall:

1. support the role of a participating MCPTT function as specified in 3GPP TS 23.379 [5];

2. distribute floor control messages as described in clause 6.3 and support associated procedures as specified in clause 6.4;

3. support call setup control over a pre-established session as specified in clause 9.3;

4. when operating in systems that support and employ MBMS functionality, act as a GCS AS as specified in 3GPP TS 29.468 [6] and execute the related MBMS subchannel control procedures as specified in clause 10.2; and

5. support media plane security as specified in clause 13.

5.5 Non-controlling MCPTT function

An MCPTT server providing the non-controlling MCPTT function of an MCPTT group shall:

1. support floor control involving groups from multiple MCPTT systems as specified in 3GPP TS 24.379 [2];

2. provide a floor control interface towards the controlling MCPTT function as described in clause 4.2.4 and support the related procedures as specified in clause 6.5;

3. provide a media interface towards the controlling MCPTT function as described in clause 4.2.4 and support the related procedure as specified in clause 6.5;

4. provide a media distributor as described in clause 4.2.4 and the related procedures as specified in clause 6.5; and

5. support media plane security as specified in clause 13.