Content for  TS 22.280  Word version:  19.4.0

[R-6.8.6.1-001] [R-6.8.6.1-002]

[R-6.8.6.2-001] [R-6.8.6.2-002] [R-6.8.6.2-003] [R-6.8.6.2-004] [R-6.8.6.2-005]

Dispatchers from different critical communication organizations access the same networks and network resources. Depending on the event, the priority is given to an organization and/or a group rather than to another. For instance, in case of a fire priority is given to the fire brigades dealing with it, while in case of a criminal arrest priority is given to the police officers in charge of the arrest.

[R-6.8.7.2-001] [R-6.8.7.2-002] [R-6.8.7.2-003]

• an application layer pre-emption capability;
• a capability to be pre-empted; and
• an application layer priority value.

[R-6.8.7.2-004] [R-6.8.7.2-005] [R-6.8.7.2-006] [R-6.8.7.2-007] [R-6.8.7.2-008] [R-6.8.7.2-009] [R-6.8.7.2-010]

[R-6.8.8.1-001] [R-6.8.8.1-002] [R-6.8.8.1-003] [R-6.8.8.1-004]

[R-6.8.8.2-001] [R-6.8.8.2-002] [R-6.8.8.2-003] [R-6.8.8.2-004]

[R-6.8.8.3-001] [R-6.8.8.3-002] [R-6.8.8.3-003]

[R-8.8.8.5-001]

Ambient listening is a feature that allows an authorized MCX User, typically a dispatcher, to cause an MCX UE to initiate a communication which results in no indication on the MCX UE that it is transmitting. Ambient listening can be initiated by an authorized MCX User who wants to be "listened" to by another remote authorized MCX User or can be initiated by a remote authorized MCX User who wants to "listen" to another MCX User. The purpose of this feature allows a dispatcher to "listen" to activities at the Location of the remote MCX UE to find out what is happening around that MCX UE without providing an indication to the MCX User or people around the user (whom the MCX User does not want to make aware of this action) that this is happening. This type of communication is different from other types of communications, as for ambient listening information is only transmitted to one party in the communication (i.e., a dispatcher or an authorized MCX User that is acting in a similar role to a dispatcher). This is used for stolen MCX UEs, monitoring officers, officer safety and particular operations, where it is important that the MCX UE does not indicate what is happening.

A Remotely initiated MCX Service Communication is a feature that allows an authorized user, typically a dispatcher, to cause a remote MCX UE to initiate a communication by itself, without its user explicitly initiating the communication manually. The purpose of this feature allows the dispatcher to "listen" to activities at the Location of the remote MCX UE to find out what is happening around that MCX UE. This feature is also known as "Remote Unit Monitoring" in P25 systems. There are two typical use cases for this feature. The first one is the case where a user could have been incapacitated. This could be both accidentally, say a traffic accident, or deliberately, for example a violent attack. In both cases it would be necessary to remotely initiate a communication from the MCX UE in order to allow another user or a group of users to "listen" to what is happening to prepare assistance. The communication that is set up is either a Private Communication or a Group Communication, and the communication could optionally be visible to the remote MCX UE's user. The second one is the case of a stolen MCX UE. Here it is just necessary to activate the MCX UE so that a dispatcher can "listen" to any background communication in order to make an analysis of the situation. In this situation, the initiation of the communication from the remote MCX UE, typically a Private Communication in that case, is not visible by that MCX UE's user. Other use cases, such as undercover operations, discreet surveillance of users or investigations, could exist depending on the missions of the critical communications users and on legislations. The behaviour of the remotely initiated Communication is not different from a normal communication initiated by the local MCX User. The same rules for resource allocation and interactions with other services apply, but the initiator of the feature can have the capability to request a pre-emptive or high priority for that Communication to ensure it is set up even in case of resource congestion or to limit disturbance by other services.

[R-6.15.3.2-001] [R-6.15.3.2-002] [R-6.15.3.2-003] [R-6.15.3.2-004]

Due to an incident in an area, or a special operation, it can be necessary to coordinate MCX Users using Group Communication where these users do not normally work together and do not share any groups in common. MCX Service Ad hoc Group Communication enables authorized users to combine a random set of MCX Users into a group communication. The main characteristics of this ad hoc group communication are:

1. The ad hoc group does not exist until it is spontaneously created during the communication.
2. The ad hoc group ceases to exist when the communication terminates.

A single communication consists of one or more media transmissions until explicitly terminated by various means. MCX Users that are being combined in an ad hoc group communication may be served by the same or different MCX systems and may normally use MCX Service Groups with different security and priority levels, different floor control methods, and other different operational characteristics. The MCX Service Ad hoc Group Communication will use a common security level, priority level, floor control method, and set of operational characteristics for the participants during a communication. As with any group communication, the priority level can change dynamically. The ad hoc group is used for a single communication and it does not persist when the communication is terminated. Authorized users can recreate the ad hoc group for subsequent communications, or request creation of a permanent MCX Service Group from the participants in the ad hoc group communication.

[R-6.15.5.2-001] [R-6.15.5.2-001a] [R-6.15.5.2-001b] [R-6.15.5.2-001c] [R-6.15.5.2-002] [R-6.15.5.2-003] [R-6.15.5.2-004] [R-6.15.5.2-005] [R-6.15.5.2-006] [R-6.15.5.2-007] [R-6.15.5.2-008] [R-6.15.5.2-009] [R-6.15.5.2-010] [R-6.15.5.2-011] [R-6.15.5.2-012] [R-6.15.5.2-013] [R-6.15.5.2-014] [R-6.15.5.2-014a] [R-6.15.5.2-015]

[R-6.15.5.3-001] [R-6.15.5.3-002] [R-6.15.5.3-003] [R-6.15.5.3-004] [R-6.15.5.3-005]

[R-6.15.5.4-001]

Due to an incident in an area, or a special operation, it can be necessary to coordinate MCX Users using Ad hoc Group Emergency Alert where these users do not normally work together and do not share any groups in common. MCX Service Ad hoc Group Emergency Alert enables authorized users to combine a random set of MCX Users based on criteria into a group and to send an emergency alert to this set of MCX Users. The main characteristics of the Ad hoc Group Emergency Alert are:

1. The ad hoc group does not exist until it is spontaneously created at the initiation of the Ad hoc Group Emergency Alert.
2. After initiation of the Ad hoc Group Emergency Alert the MCX User may be put into the MCX Service Emergency State.
3. After initiation of the Ad hoc Group Emergency Alert the resulting ad hoc group may be used for group communications.
4. The ad hoc group ceases to exist when the group communications in the ad hoc group have terminated, and the Ad hoc Group Emergency Alert has been cancelled.
   An authorised user is able to:
   1. Initiate an MCX Service Ad hoc Group Emergency Alert with participants satisfying specific criteria,
   2. Cancel an MCX Service Ad hoc Group Emergency Alert,

During an ongoing MCX Service Ad hoc Group Emergency Alert, the set of MCX Users may change dynamically based on these criteria (e.g., criteria may not longer be met, or criteria may be met for additional MCX users, and as a result users are removed from or added to the ongoing Ad hoc Group Emergency Alert).

[R-6.15.6.2-001] [R-6.15.6.2-002] [R-6.15.6.2-002a] [R-6.15.6.2-003] [R-6.15.6.2-004] [R-6.15.6.2-004a] [R-6.15.6.2-005] [R-6.15.6.2-005a] [R-6.15.6.2-005b] [R-6.15.6.2-006] [R-6.15.6.2-007] [R-6.15.6.2-008]

[R-6.15.6.3-001] [R-6.15.6.3-002] [R-6.15.6.3-003] [R-6.15.6.3-004] [R-6.15.6.3-005]

[R-6.17.3.1-001] [R-6.17.3.1-002] [R-6.17.3.1-003] [R-6.17.3.1-004] [R-6.17.3.1-005]

[R.6.17.3.2-001] [R.6.17.3.2-002]

[R-6.19.1.1-001] [R-6.19.1.1-002] [R-6.19.1.1-003] [R-6.19.1.1-004] [R-6.19.1.1-005] [R-6.19.1.1-005a] [R-6.19.1.1-006] [R-6.19.1.1-007]