A.3 Harmonized multi-agency use case
22.4683GPPGroup Communication System Enablers (GCSE)Release 17TS
A.3.1 Description
This use case illustrates a situation where a GCSE group of personnel from one local agency (e.g. fire fighters) will need to be joined with other GCSE groups of personnel from other agencies representing the same locality (e.g. police, ambulance), or with other GCSE groups from national, international or adjacent localities (e.g. police from an adjacent force, national authorities, or authorities from an adjacent country). In all cases the various groups which form the composite group must be able to join/leave the composite group and be identified as members of it. The individual personnel must also be able to fully participate in multimedia sessions within the composite group (i.e. take the floor, receive broadcast communications, etc.).
A.3.2 Actors
A group of local fire fighters, called to an explosion and gas leak from a chemical facility close to a national border.
The local fire service dispatcher.
A group of local ambulance personnel, called to attend to casualties at the site.
A group of local police officers, called to evacuate residents downwind of the leak in the same country.
A group of police officers in the adjacent country, called to prepare for possible evacuation of residents downwind of the leak in their territory.
A.3.3 Pre-conditions
The local fire fighters are members of GCSE Group A.
The local ambulance personnel are members of GCSE Group B.
The local police officers are members of GCSE Group C.
The group of police officers in the adjacent country are members of GCSE Group Z.
The GCSE applications on the UEs in all four groups are compatible, and are able to interwork with one another and with any of the four individual GCSE servers which may eventually control them.
A.3.4 Service flows
1- The local fire fighters are called to the scene and use GCSE Group A. They notice casualties. The local ambulance personnel attend to the casualties and use GCSE Group B.
2- A second chemical storage tank is seen to be in imminent danger of rupture so the Fire Service Dispatcher adds GCSE Group B to Group A to form a composite group, in order to keep Ambulance personnel appraised of the situation. Members of both groups are able to use the composite group to communicate amongst each other using all the common capabilities of the GCSE clients resident on their UEs.
3- The local police officers are called to the surrounding area in order to evacuate nearby residents and prevent others from entering. They use GCSE Group C. The Fire Service Dispatcher adds GCSE Group C to the composite group in order to keep them appraised. Members of all three groups are able to use the composite group to communicate amongst each other using all the common capabilities of the GCSE clients resident on their UEs.
4- The prevailing wind carries the gas cloud from the initial leak towards the national border so the Police Authority in the adjacent country mobilises their local force to prepare residents for evacuation. They use GCSE Group Z.
5- The Fire Service Dispatcher adds GCSE Group Z to the composite group to keep the police force in the adjacent country appraised. Members of all four groups are able to use the composite group to communicate amongst each other using all the common capabilities of the GCSE clients resident on their UEs.
6- The second chemical storage tank is successfully damped down by the local fire service, made safe, and further danger is averted. The initial gas cloud dissipates to a safe level.
7- The local fire fighters inform the Fire Service Dispatcher that all is safe. The Fire Service Dispatcher is able to inform all members of the composite group that the incident is over.
A.3.5 Post-condition
Having informed the composite group members that all is safe the Fire Service Dispatcher dissolves the composite group.
Communications between members of the four individual GCSE groups continue within the separate groups A, B, C, and Z.
Annex B (informative):
Group communication concept(s)
From the 3GPP network perspective the concept of a group communication appears to be a foreign concept. The concept of group communication has been the underpinnings of public safety communications currently and in the past, not point to point communications. A group communication is the ability for a set of devices to be considered as a whole. In these public safety systems the method for identifying a group communication has evolved from a particular radio frequency to an abstraction (i.e., a logical group identifier). The logical Venn diagram shown in figure 1 shows the concept of a group communication considering three characteristics: a member of a group (A), the device is reachable (R), and the device wants to participate (P).
Figure B.1: Group characteristics
The truth table shown in Table B.1 provides the expected actions that the 3GPP network must provide to the device based on these three characteristics.
Table B.1: Expected actions
|
representative device |
member of group |
reachable |
wants to participate |
actions |
|
x8 |
T |
T |
T |
receives notice, receives call, participates in communication |
|
x7 |
T |
T |
F |
receives notice, receives call, does not participate |
|
x6 |
T |
F |
T |
does not receive notice, does not receive call, does not participate |
|
x5 |
T |
F |
F |
does not receive notice, does not receive call, does not participate |
|
x4 |
F |
T |
T |
does not receive notice, does not receive call, does not participate |
|
x3 |
F |
T |
F |
does not receive notice, does not receive call, does not participate |
|
x2 |
F |
F |
T |
does not receive notice, does not receive call, does not participate |
|
x1 |
F |
F |
F |
does not receive notice, does not receive call, does not participate |
Using these characteristics the 3GPP network needs to know the devices that make up the group communication so that it can make the appropriate inquiries and make the correct decisions to determine reachability, membership, and participation. The condition (or indication) to participate may be at the device level or may be a decision made by the user of the device. The 3GPP network is the only entity that knows whether a device is reachable. The application layer can indirectly obtain the reachability information from the 3GPP network (e.g., be using it to deliver an application "ping" message). As one can see from Table 1 the actual devices that will compose the group communication may not be all of the devices that are listed as members of a group.
Annex C (informative):
Description of usage of GCSE for public safety
Based on real life scenarios, at least 36 simultaneous voice group communications involving a total of at least 2000 participating users in an area , with up to 500 users being able to participate in the same group could be expected.
Annex D (informative):
Change history
|
Change history |
|||||||||||
|
TSG SA# |
SA Doc. |
SA1 Doc |
Spec |
CR |
Rev |
Rel |
Cat |
Subject/Comment |
Old |
New |
WI |
|
SP-60 |
SP-130292 |
– |
22.468 |
– |
– |
– |
One-step-approved by SA#60 |
1.0.1 |
12.0.0 |
GCSE_LTE |
|
|
SP-66 |
SP-140753 |
S1-144547 |
22.468 |
13 |
Rel-13 |
C |
Removing floor control requirements from GCSE_LTE |
12.0.0 |
13.0.0 |
GCSE_LTE |
|
|
SP-75 |
– |
– |
– |
– |
Rel-14 |
– |
– |
13.0.0 |
14.0.0 |
– |
|
|
SP-80 |
SP-180306 |
0014 |
1 |
F |
Removal of LTE specific terminology from 22.468 |
14.0.0 |
15.0.0 |
||||
|
Change history |
|||||||
|
Date |
Meeting |
TDoc |
CR |
Rev |
Cat |
Subject/Comment |
New version |
|
2019-12 |
SA#86 |
– |
– |
– |
– |
Comment: V.16.0.0 identical to v.15.0.0. Created because of Rel-17 CR 0016r3 (in SP-191014) on a Rel-15 spec. |
16.0.0 |
|
2019-12 |
SA#86 |
SP-191014 |
0016 |
3 |
B |
Introduction of NCIS Service Requirements |
17.0.0 |
|
2020-07 |
– |
– |
– |
– |
– |
Wrong file in 3GU ("22468-h00.zip" actually contained v.16.0.0 instead of 17.0.0) |
17.0.1 |