Description
The MCVideo Imminent Peril Group Call (MVIGC) is the actual communication session instantiated for an MVIG when an imminent peril situation is declared. It is a specific type of Mission Critical Group Call that utilizes the MCVideo service enablers to establish a real-time, multimedia group communication session with video as a primary medium. The call is characterized by its high priority and potential to pre-empt other network traffic. The process begins when an authorized user or system (e.g., a dispatcher application) initiates an MVIGC request, referencing a specific MVIG identifier. This request is sent to the MCVideo application server, which authenticates the request and retrieves the MVIG configuration.
Architecturally, the MCVideo AS then interacts with the underlying 3GPP network—initially the Evolved Packet Core (EPC) in LTE or the 5G Core Network (5GC)—to establish the necessary bearer resources for the group call. This involves signaling to the Policy Control Function (PCF) and Session Management Function (SMF) to apply a dedicated QoS policy for the MVIGC, ensuring guaranteed bitrate, priority, and potentially pre-emptive capabilities. The network establishes individual bearers or QoS Flows for each member of the MVIG, connecting them to a common multimedia resource function that mixes and distributes the video and audio streams. Key components involved include the MCVideo AS, the Group Communication System Application Server (GCS AS), the Media Resource Function (MRF), and the core network's policy and session management entities.
Its role is to provide an immediate, reliable, and high-quality video conference for emergency responders. The call setup is optimized for speed, often bypassing normal ringing procedures to automatically connect all members. During the call, floor control mechanisms manage who can speak or share video, and the session persists until explicitly terminated. The MVIGC leverages the group definition to ensure all necessary personnel are included and that the network treats this communication as the most critical traffic, which is essential for maintaining situational awareness and command coordination during a fast-evolving crisis.
Purpose & Motivation
The MVIGC was standardized to fulfill the requirement for an instant, video-based group communication channel that activates automatically upon the declaration of an emergency. Traditional teleconferencing or push-to-talk over cellular (PoC) solutions lacked the guaranteed priority, pre-emption, and rapid setup mechanisms needed for life-or-death situations. First responders required a system where a single alert could launch a full video conference with all relevant parties, without any manual dialing or connection delays.
MVIGC solves the critical gap between identifying an imminent peril group and actually establishing a working communication channel for that group. It operationalizes the MVIG concept. The motivation stemmed from public safety agencies' need to leverage broadband video for improved situational awareness—seeing a disaster scene, a suspect, or a building layout—while retaining the instant group connect feature of their old radio systems. By defining MVIGC as a standardized service, 3GPP ensured that different vendors' mission critical applications and networks could interoperate to deliver this vital function, enabling effective multi-agency response during major incidents.
Classification
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (121 CRs across 5 releases). Complements the general historical overview above with the evidence-based evolution of this function.
Studied in Rel-14, normative work from Rel-15.
In Release 15, the MCVideo Imminent Peril Group Call (MVIGC) function was introduced as a new call type, with the specification defining the distinct "MCVideo imminent peril group call state" maintained by the client. The release provided the call control protocol to support this feature for both on-network and off-network operational environments, as part of the broader support for mission-critical emergency communications.
- MCVideo ambient viewing client procedures TS 24.281CR0033
- MCVideo ambient viewing participating MCVideo function procedures and controlling MCVideo function procedures TS 24.281CR0034
- MCVideo ambient viewing general description TS 24.281CR0035
- Usage of MBMS for MCVideo - signaling control TS 24.281CR0037
- Subscription to group dynamic data TS 24.281CR0061
- Correction to session-type in XML schema for MCVideo Information TS 24.281CR0039
+ 9 more changes
In Release 16, the MVIGC (MCVideo Imminent Peril Group Call) function was enhanced to support off-network operation, extending its use beyond on-network deployments. Furthermore, the release introduced corrections and fixes for critical elements such as the alert mechanism, location data schema, and emergency upgrade procedures to improve reliability. These updates were finalized with the completion of the IANA registration for the MCVideo protocol parameters.
In Release 17, the new MVIGC (MCVideo Imminent peril Group Call) function was introduced as a distinct call type, with the specification defining the specific client-side "MCVideo imminent peril group call state" to manage its lifecycle. This addition was part of broader enhancements for mission-critical communications, which also included new procedures for interconnect scenarios, functional alias usage, and more precise location reporting with altitude and accuracy data in the MCVideo location XML schema.
- Functional Alias usage in MCVideo Call TS 24.281CR0093
- Add altitude, timestamp to MCVideo location XML schema TS 24.281CR0095
- Add preconfigured regroup to MCVideo TS 24.281CR0096
- Control per service authorizations limit for MCVideo service TS 24.281CR0100
- Check for Preconfigured Group Use Only TS 24.281CR0104
- Call control - Restricting MCVideo private communications TS 24.281CR0105
+ 34 more changes
In Release 18, the MVIGC (MCVideo Imminent Peril Group Call) function was enhanced by introducing support for emergency and imminent peril ad hoc group calls, as specified in the new call control protocol. This release also defined the distinct "MCVideo imminent peril group call state" for client-side management of such calls, expanding the service's critical communications capabilities.
- Use of 5G MBS transmission in MCVideo signalling plane TS 24.281CR0199
- Add the description of 5MBS in MCVideo TS 24.281CR0220
- MCVideo support of multiplexing - SDP offers and answers TS 24.281CR0215
- Support MCVideo over 5G ProSe TS 24.281CR0225
- General adhoc group call procedures in single system - Protoc impl for MCVideo TS 24.281CR0221
- Adhoc group call participants modify procedures in single system - protoc impl MCVideo TS 24.281CR0226
+ 35 more changes
In Release 19, enhancements for the MVIGC (MCVideo Imminent peril Group Call) function included refined criteria for dynamically determining participants during an ongoing ad hoc group call or emergency alert. The release also introduced authorization for users to modify or release such calls based on local policy and improved the handling of participant lists within SIP messages. Additionally, corrections were made to ensure proper client operation and schema definitions for group communications.
- Modify list of participants by changing the criteria during an ongoing MCVideo ad hoc group call TS 24.281CR0278
- Adhoc group emergency alert add criteria to the SIP message containing the participant lists sent to the authorised users TS 24.281CR0279
- MCVideo adhoc group call to migrated user TS 24.281CR0280
- Modifying the criteria for determining the participants during an ongoing ad hoc group emergency alert TS 24.281CR0282
- Ad hoc group call release by an authorized user TS 24.281CR0289
- FRMCS_Ph5 Adding reason to leave a session in MCVideo TS 24.281CR0290
+ 13 more changes
Explore further
Broader topics and technologies where MVIGC plays a role.
Defining Specifications
3GPP specifications that define or reference MVIGC, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TS 24.281 vj40 | MCVideo Signalling Control Specification | Rel-19 |
| TS 37.579 vi40 | Mission Critical services conformance testing | Rel-18 |