Communication Service Requirements for Critical Medical Applications
Lagrange, Mathieu, b<>com
Study on CMED
Mathieu Lagrange, b<>com
Stage 1 of CMED
Lagrange, Mathieu, b<>com
Summary based on the input provided by b<>com in SP-220652.
This WI aims at defining 5G communication services requirements for critical medical applications, e.g. medical applications targeting the delivery of serious care to patients, such as:
Image Assisted Surgery inside hybrid operating rooms equipped with high quality and augmented imaging systems
Robotic Aided Surgery inside hybrid operating rooms or in remote medical facilities
Tele-diagnosis and patient vital-signal monitoring in ambulances, hospitals, or remote healthcare facilities
The generated requirements cover network dependability, performances, medical data confidentiality and integrity, network auditability (to demonstrate to regulators that patient safety and privacy is maintained), and more generally specific 5G functionalities.
During the work, it has been detected that due to the very specific nature of the targeted vertical, several performance requirements look out of reach for current technology. For example, surgeons pay a lot of attention to video quality (very high resolution, frame rates, …) and repeatedly ask for non-compressed video streams to avoid artifacts and to lower application latencies during non-invasive surgery. This led to very stringent data rate requirements (several dozen or higher Gbps in some identified use cases).
Interestingly, it has been noted that some of the requirements covered as part of CMED are similar to those generated by VIAPA (video, imaging, and audio for professional applications) and this has led to a joint specification for the two work items. For VIAPA, see section "Enhanced support of Non-Public Networks".
Beside SA1, no specific stage 2 nor stage 3 work could be carried out in 3GPP downstream groups as key performance requirements (bitrate, latency, …) were felt too stringent for current technology generation.
SA1 part: Audio-Visual Service Production (AVPROD)
Summary based on the input provided by BBC in xP-22xxxx.
AVPROD looks at applications for Programme Making and Special Events (PMSE) and use cases for media production.
It looks specifically at PMSE use cases and VIAPA (Video Imaging and Audio for Professional Applications expands this to include areas such as medical and gaming.
The documents introduce requirements related to professional video, imaging and audio services. Unlike other consumer multimedia applications envisioned for 3GPP systems, the applications in which this document focuses have more demanding performance targets and includes user devices that are managed in different workflows when compared to typical UEs.
This can be divided into two main categories: contribution and production.
Contribution links are heavily compressed and have lower latency requirements and are used for newsgathering and other programme items. They are currently serviced by satellite or bonded cellular and use the PLMNs
Production links have higher bandwidth, due to less compression, and challenging latency requirements as well as strict Quality of Service metrics to ensure reliability.
The key parameters for these applications are:
In video production, overall system latency is referred to as imaging system latency and has an impact on the timing of synchronized cameras. For audio applications, overall system latency is referred to as mouth to ear latency and it is critical to maintain lip sync and avoid a performer to be put off by hearing their own echo. Finally, in medical applications the system latency impairs the achievable precision at a given gesture speed as it translates the time needed to traverse the whole imaging system into a geometrical error of the instruments position.
Video and imaging applications have extremely high uplink bandwidth requirements and while compression may be used to mitigate this in certain user cases it often degrades the picture to the extent onward processing required by some applications is compromised. For Video Production certain standards have been determined which indicate the maximum allowable compression for a given type of production. In medical imaging, compression may introduce artefacts which can impact on diagnosis of critical illness and may also introduce additional delays which, in image assisted surgery, translate into misalignment between perceived instruments position on screen and their real position into patients' body.
Quality of Service:
For Video Production certain standards have been determined which indicate the maximum allowable compression for a given type of production. In medical imaging, compression may introduce artefacts which can impact on diagnosis of critical illness and may also introduce additional delays which, in image assisted surgery, translate into misalignment between perceived instruments position on screen and their real position into patients' body.
VIAPA also highlights service aspects for Non-Public networks, clock synchronization, Network exposure, service continuity and multi-network connectivity.
Performance requirements are defined for all applications.
There are no specific Stage 2/3 works needed after the Stage 1 requirements, but work has continued in SA4 with the study item on NPNs for media production.
SA4 part: Study on Media Production over 5G NPN
Summary based on the input provided by Ericsson in SP-220650.
The media production industry uses its own set of codecs, protocols and procedures for IP-based media production. These protocols are (often) targeting dedicated networks installed at a production facility or at a temporary location, which allow transmission of either uncompressed or compressed video at high quality. For the orchestration and configuration of an IP-based media production setup, different solutions are defined.
There are cases for which the Media Producer may own their own 5G Network. There are other cases for which the media producer collaborates with a 5G Network operator to support media production events and services. Different collaboration scenarios require different means to establish 5G-based media production connectivity.
In deployments, 5G Systems including NPNs may have to be tailored to the needs of each industry vertical and the target use-case in question. The Media Production vertical may want to use the 5G System for different purposes, primarily for sending video and audio from remote locations to a central production studio, but also for return video, tally, talkback, remote device control (connectivity configuration, but also operational control of specialist UE). One aim of the study would be to identify how (in technical terms) media production can beneficially use 5G systems for media production.
TR 26.805 documents the findings of the Study on Media Production over 5G NPNs. The document contains an elaborative description on different protocols and workflows used in media production at the time of writing. Several different standardization and industry fora are defining Ethernet- and IP-based protocols for media production purposes.
While the study has not identified an urgent technical area for standardisation at this point in time, a number of practical guidelines for implementers are identified and documented in the Technical Report. Those are intended to support media production device manufactures and media producers to leverage different 3GPP features for their purposes.
These guidelines may be further promoted and expanded, and more specific aspects are likely worthwhile to be defined. Communication with external organizations such as 5G-MAG is recommended in order to identify if they would follow up on those guidelines to support media production device manufactures and media producers to leverage different 3GPP features for their purposes.
Study on Architectural enhancements for 5G multicast-broadcast services
Meng Li, Huawei
Stage 2 for 5MBS
Meng Li, Huawei
CT1 aspects of 5MBS
Gulbani, Giorgi, Huawei
CT3 aspects of 5MBS
Gulbani, Giorgi, Huawei
CT4 aspects of 5MBS
Gulbani, Giorgi, Huawei
Summary based on the input provided by Huawei, HiSilicon in SP-220587.
5G multicast and broadcast service specifies architectural enhancements to the 5G system using NR to support multicast and broadcast communication services; encompasses support for functions such as how to deliver multicast and broadcast communications including support within certain location areas, mobility, MBS session management and QoS; and covers interworking with E-UTRAN and EPC based eMBMS for Public Safety (e.g. MCX services).
The WI is linked to the RAN WI on NR Multicast and Broadcast Services .
As documented in TS 23.247, the following features for 5G multicast and broadcast service are specified:
Architectural enhancement. MBS Architecture defined in TS 23.247 follows the 5G System architectural principles, enabling distribution of the MBS data from the 5GS ingress to NG-RAN node(s) and then to the UE.
QoS model and parameters as defined in TS 23.501 also apply to multicast/broadcast communication services with several differences documented in TS 23.247. The policy and charging control framework as defined in TS 23.503 applies to Multicast and Broadcast services, i.e., for MBS Session binding, QoS Flow binding, PCC rules for MBS Session, and Policy information.
5GC Individual MBS traffic delivery is for multicast only, and in which 5GC receives a single copy of multicast packets and delivers separate copies of those multicast packets to individual UEs via per-UE PDU sessions, hence for each such UE one PDU session is required to be associated with a Multicast MBS Session. 5GC Shared MBS traffic delivery can be used for multicast and broadcast, and in which 5GC receives a single copy of MBS data packets and delivers a single copy of those MBS data packets to a RAN node. See following Figure 22.214.171.124.1-1 for details.
5GC should authorize the AF for delivering MBS data to the 5GC and/or interacting with the 5GC. NEF perform authorization to the external AF for determination of whether the interaction with the 5GC is allowed or not.
Multicast communication service. It aims at providing the same service and same specific content data to a dedicated set of UEs. The following characteristics for multicast are included in the WI.
For Multicast MBS session, 5GC authorizes the UE based on the MBS subscription data, based on MBS subscription data of the UE, and the MBS session information.
Local multicast service is the multicast MBS service limited in a certain MBS service area, and it is enforced by NG-RAN node and 5GC. A location dependent multicast service is an MBS service provided in several MBS service area(s), when UE moves to a new MBS service area, content data from the new MBS service area shall be delivered to the UE, and the network ceases to deliver the content data from the old MBS service areas to the UE.
Mobility support of MBS service. UE may move from one NG-RAN node to another NG-RAN node after UE has joined the MB Session. To minimize the data loss of the UE during the handover procedure, multicast MBS session data may be forwarded from source NG-RAN node to target NG-RAN node.
Session activation and deactivation. The MBS Session activation procedure is used for activating the resources for MBS data at NG-RAN node. The MBS Session deactivation procedure is used for deactivating the resources for MBS data at NG-RAN node. Resources can be efficiently used by a proper control of session activation/deactivation.
Broadcast communication service. It is to provide the same service and the same specific content data are provided simultaneously to all UEs in a geographical area. For Location dependent broadcast service, it is similar as the one for multicast.
Inter-system mobility with interworking at service layer. In order to minimize the interruption of services, upon mobility for MBS service from NR/5GC to E-UTRAN/EPC and vice versa, the interworking is supported at service layer.
Security for multicast/broadcast service. As defined in TS 33.501, control-plane procedure and user-plane procedure are optionally supported in service layer for security protection of MBS traffic. The user plane security between UE and RAN shall be deactivated when 5GC shared MBS traffic delivery method for MBS data transmission is used to avoid redundant protection.
Summary based on the input provided by Huawei, HiSilicon in RP-220408.
This Rel-17 NR MBS WI specifies two delivery modes, i.e. MBS multicast and MBS broadcast, for services of PTM (Point-To-Multipoint) nature, such as for example public safety and mission critical services, V2X applications, IPTV, live video, software delivery over wireless and IoT applications.
Before introducing NR MBS, there was no broadcast/multicast transmission supported in NR for user data delivery. Services of PTM nature could only be delivered over NR based on unicast, which is inefficient, in particular from radio resources utilization point of view. Nevertheless, for the use cases mentioned above, broadcast/multicast transmission provides substantial benefits, especially in terms of system efficiency and user experience. The MBS multicast delivery mode is capable of addressing higher QoS services while the MBS broadcast delivery mode is focusing on lower QoS services.
The objectives of NR MBS WI are included in , and the WI is linked to the SA2 WI on Architectural enhancements for 5G multicast-broadcast services .
MBS Multicast: MBS multicast provides the MBS delivery mode for RRC_CONNECTED mode UEs, with the following characteristics:
Group scheduling: A common frequency resource (CFR) is defined for multicast scheduling as an 'MBS frequency region' with a number of contiguous PRBs, which is configured within the dedicated unicast BWP. A group of UEs can be configured via RRC signalling with a G-RNTI for group scheduling, and the group of UEs can also be configured with downlink SPS and G-CS-RNTI for MBS multicast. The gNB schedules a transport block using G-RNTI (or G-CS-RNTI) to the group of UEs.
HARQ feedback: HARQ feedback is used to further improve the group scheduling efficiency, and the following two HARQ feedback reporting modes are supported:
In the first HARQ feedback reporting mode, the UE transmits a PUCCH with HARQ-ACK information if the UE has correctly received the transport block or HARQ-NACK value if the UE has not correctly received the transport block.
For the second HARQ feedback reporting mode, the UE transmits a PUCCH with HARQ-NACK information only if the UE has not correctly received the transport block.
HARQ reporting for multicast can also be disabled for a UE either semi-statically or dynamically.
Dynamic PTP (Point-To-Point)/PTM switch for MBS multicast
It is not always efficient for a gNB to schedule data based on G-RNTI (PTM), and sometimes PTP based scheduling (same as unicast) can bring more benefits thanks to the advanced unicast mechanisms. Based on the common PDCP entity, the gNB can decide whether to use PTM or PTP to deliver data of an MBS multicast session to the UE(s) at a certain time. The gNB makes its decision based on information such as MBS Session QoS requirements, the number of jointly scheduled UEs, UE feedback on link quality, and other criteria and ensures QoS requirements to be met for the service regardless of the chosen transmission method.
Lossless handover for MBS multicast: To support high QoS services, it is necessary to ensure lossless data delivery also during a handover. To enable lossless handover, synchronisation of PDCP SNs among source and target RAN nodes should be ensured, by either or a combination of the following methods:
Derivation of the PDCP SNs from DL MBS QFI SNs provided on NG-U;
Deployment of a Shared NG-U Termination at NG-RAN, shared among gNBs, which comprises a common entity for assignment of PDCP SNs.
MBS Broadcast: MBS broadcast provides the downlink only MBS delivery mode for UE in all RRC states, addressing lower QoS services, with the following characteristics:
Group scheduling: A common frequency resource (CFR) is defined for broadcast scheduling as an 'MBS frequency region' with a number of contiguous PRBs in which G-RNTI can be used to schedule the associated MBS broadcast service. The bandwidth of CFR can be equal to or larger than initial BWP, which is indicated by system information. HARQ feedback and HARQ re-transmission is not supported for MBS broadcast.
MBS broadcast Configuration: The UE can receive the MBS configuration for a broadcast service via a broadcast control channel, i.e. MCCH, which is the same for UEs in RRC_IDLE , RRC_INACTIVE and RRC_CONNECTED states.
Service continuity: Lossless mobility cannot be ensured for MBS broadcast, but some mechanisms are specified to support service continuity of the broadcast service. NR MBS broadcast supports MBS frequency prioritization, which enables the UE in RRC_IDLE/RRC_INACTIVE to select the right frequency to camp on and receive its services of interest.
To ensure service continuity of MBS broadcast for UEs in RRC_CONNECTED, the UE can send MBS Interest Indication to the gNB and the gNB can configure the UE in a way allowing it to receive the services the UE is interested in using MBS broadcast.
Summary based on the input provided by Qualcomm in SP-220636.
The 5G MBS User Services had been developed by SA4 within the 5MBUSA Work Item, and the stage 2 architecture and procedures are documented in TS 26.502. In addition, architectural extensions to the delivery of 5GMS via eMBMS had been documented TS 26.501 as part of the 5MBUSA work item. This work item now addresses relevant stage-3 specifications for 5MBS and 5GMS via eMBMS as follows:
Stage 3 format and protocol for User Service Announcement (between MBSF and MBS Client) are specified in a new specification TS 26.517, addressing reference point M5.
Stage 3 protocols for the MBS distribution methods (between MBSTF and MBS Client) based on existing MBMS delivery methods are specified, addressing reference point M4, namely
Object distribution methods, based on download delivery methods defined in MBMS with reference to TS 26.346.
Packet distribution methods, based on transparent delivery methods with reference to TS 26.346.
Study on Multicast Architecture Enhancements for 5G Media Streaming
Peng Tan, Telus
Summary based on the input provided by TELUS in SP-220646.
This Study is about potential architecture enhancement to enable 5G multicast-broadcast media streaming. It further provides recommendations for normative specification work on a generic 5G MBS User Service Architecture.
The following key issues are studied in this work item:
Support of Multicast ABR in 5G Media Streaming Architecture
Nmb2 Design Considerations
Collaboration and Deployment Scenarios
Reuse of MBMS Service Layer
Client Architecture Options
5GMS via eMBMS
This study concludes that functional entities for a generic 5G MBS User Service Architecture are determined to be defined in normative specification TS 26.502 to support 5G Multicast-Broadcast applications. It presents a complete service offering to an end-user, via a set of APIs that allows the MBS Client to activate or deactivate reception of the service.
The 5MBS User Service architecture is independent of 5G Media Streaming (5GMS) and may or may not be used by 5GMS. 5G Multicast ABR media streaming service could be a User Service where the MBS User Services allow streaming of DASH content as defined in TS 26.501, and it also includes the use of an MBS session to deliver the DASH segments in multicast. When delivering content to a MBS Client, the MBSTF uses one or more MBS Delivery Methods.
5G Multicast-Broadcast User Service Architecture and related 5GMS Extensions
TAN, PENG, TELUS
Summary based on the input provided by TELUS in SP-221269.
This Work Item has resulted in a new specification TS 26.502 entitled "5G multicast-broadcast services, User Service architecture" and in CRs to TS 26.501, to support 5G Media Streaming (5GMS) via eMBMS.
TS 26.502 defines the stage 2 5G multicast-broadcast User Services architecture as follows:
An MBS User Services network architecture that defines how MBS-related entities are involved in providing MBS User Services delivery and control.
An MBS User Services reference architecture model that describes roles of the principal network and UE functions involved.
New reference points in order to support MBS User Services, including MBS 4 MC, MBS 4 UC, MBS 5, MBS 6, MBS 7, and MBS 8 beyond the existing reference points defined in TS 23.247.
Two distribution methods for multicast/broadcast transport of objects and packets respectively.
User Services domain model and dynamic model with relevant parameters for reception reporting, ingestion and announcement.
Procedures for 5G Multicast-Broadcast User Services, including baseline procedures, and procedures for user services provisioning, advertisement/discovery, data transfer and data repair.
Network function services exposed by MBSF and MBSTF.
Informative annexes that documents deployment and collaboration models, Nmb8 User Plane ingest examples, and data model examples.
TS 26.501 further specifies the architecture to allow 5GMS-based downlink media streaming to be deployed as an MBMS-Aware Application on top of eMBMS as defined in TS 23.246, TS 26.346, TS 26.347 and TS 26.348. The procedures for the following uses cases when 5GMS uses eMBMS for delivery are defined:
5GMS content delivered exclusively via eMBMS.
5GMS consumption reporting for eMBMS.
5GMS metrics reporting procedures for eMBMS.
Procedures for hybrid 5GMS content delivery via 5G systems and eMBMS.
Procedures for dynamic provisioning of 5GMS content delivery via eMBMS.
For Frequency bands for broadcast, see the section "New bands and bandwidth allocation for 5G terrestrial broadcast - part 1"
Other specific broadcasting aspects appear in the sections on "V2V" and on "MC".
For Other Media production, professional video aspects, see section on User Plane.
WI rapporteur name/company
Study on location enhancements for mission critical services
Dom Lazara, Motorola Solutions
Broadcast / Multicast requirements supporting Mission Critical Services in 5G
Toobe, Jens, BDBOS
Study on Security Aspects of Enhancements for 5G Multicast-Broadcast Services
Longhua Guo, Huawei Technologies
Study on Mission Critical services over 5G multicast-broadcast system
Val Oprescu, AT&T
Study on Mission Critical services support over 5G System
Summary based on an input from Novamint.
This Study is about asset tracking use cases and identifies service requirements as well as new KPIs to be supported by 5G communication services for asset tracking.
Several significant use cases for Asset Tracking are described in this study item such as container, wagon, pallet. Some of these use cases and related requirements were also used as an input for REFEC (see corresponding section).
The requirements coming out from ATRAC to support low power IoT/mMTC type of communications with satellite access has been addressed on Stages 2 and 3 in study and work items on NB-IoT/eMTC support for Non-Terrestrial Networks (see corresponding section).