Integrated Sensing and Communications (ISAC) use case for CATS

Integrated Sensing and Communications (ISAC) is emerging as a key enabler for next-generation wireless networks, integrating sensing and communication functionalities within a unified system. By leveraging the same spectral, hardware, and computational resources, ISAC enhances network efficiency while enabling new capabilities such as high-resolution environment perception, object detection, and situational awareness. This paradigm shift is particularly relevant for applications requiring both reliable connectivity and precise sensing, such as autonomous vehicles, industrial automation, and smart city deployments. Given its strategic importance, ISAC has gained significant traction in standardization efforts. The ETSI Industry Specification Group (ISG) on ISAC has been established to explore technical requirements and use cases, while 3GPP has initiated discussions on ISAC-related features within its ongoing research on future 6G systems. Furthermore, research initiatives within the IEEE and IETF are investigating how ISAC can be integrated into network architectures, spectrum management, and protocol design, making it a critical area of development in the evolution of wireless networks. This document presents a use case related to ISAC, aiming to facilitate discussions within the CATS Working Group on thechallenges, and requirements. The aim for this document is to facilitate discussion in the CATS WG for potential consideration of the use case in .

Integrated Sensing and Communications (ISAC) enables wireless networks to perform simultaneous data transmission and environmental sensing. In a distributed sensing scenario, multiple network nodes --such as base stations, access points, or edge devices-- collect raw sensing data from the environment. This data can include radio frequency (RF) reflections, Doppler shifts, channel state information (CSI), or other physical-layer features that provide insights into object movement, material composition, or environmental conditions. To extract meaningful information, the collected raw data must be aggregated and processed by a designated computing node with sufficient computational resources. This requires efficient coordination between sensing nodes and computing resources to ensure timely and accurate analysis, making it a relevant use case for Computing-Aware Traffic Steering (CATS) in IETF. This use case aligns with ongoing efforts in standardization bodies such as the ETSI ISAC Industry Specification Group (ISG), particularly Work Item #5 (WI#5), titled 'Integration of Computing with ISAC'. WI#5 focuses on exploring different forms of computing integration within ISAC systems, including sensing combined with computing, communications combined with computing, and the holistic integration of ISAC with computing. The considerations outlined in this document complement ETSI's work by examining how computing-aware networking solutions, as developed within CATS, can optimize the processing and routing of ISAC sensing data. As an example, we can consider a network domain with multiple sites capable of hosting the ISAC computing "service", each with potentially different connectivity and computing characteristics. shows an exemplary scenario. Considering the connectivity and computing latencies (just as an example of metrics), the best service site is #n-1 in the example used in the Figure. Note that in the figure we stilluse the old terminology in which by ICR we mean Ingress CATS-Forwarder , and by ECR we mean Egress CATS-Forwarder.

In the distributed sensing use case, the sensed data collected by multiple nodes must be efficiently routed to a computing node capable of processing it. The choice of the computing node depends on several factors, including computational load, network congestion, and latency constraints. CATS mechanisms can optimize the selection of the processing node by dynamically steering the traffic based on computing resource availability and network conditions. Additionally, as sensing data is often time-sensitive, CATS can ensure low-latency paths while balancing computational demands across different processing entities. This capability is essential for real-time applications such as cooperative perception for autonomous systems, industrial monitoring, and smart city infrastructure.

Several challenges need to be addressed for efficient distributed sensing in ISAC-enabled networks:

Traffic Steering and Resource Allocation: Ensuring that sensing data is directed to the most suitable computing node while considering both network conditions and processing availability.

Latency Sensitivity: Many ISAC applications require near-real-time processing, necessitating low-latency and high-reliability data forwarding strategies.

Data Synchronization: Sensing nodes may have different perspectives on the environment, requiring synchronization and fusion of data streams before processing.

Scalability: As the number of participating sensing nodes increases, mechanisms must efficiently distribute and balance the computational workload.

Security and Privacy: Sensed data may contain sensitive information, requiring mechanisms for secure transmission and processing.

The integration of ISAC-based distributed sensing into CATS frameworks may require enhancements in computing-aware routing protocols, traffic steering algorithms, and signaling mechanisms. Standardization efforts could focus on defining metrics for computing-aware path selection, developing mechanisms for real-time coordination between sensing and computing nodes, and ensuring interoperability with existing network architectures. Furthermore, coordination with ETSI ISAC WI#5 may help align the development of computing-aware ISAC networking solutions with ongoing standardization efforts in computing integration, ensuring cross-industry compatibility and deployment feasibility.