Internet of Intelligent Reflecting Surfaces (IoIRS)

TL;DR

The paper identifies the limitations of transmitter-centric IRS control in future dense networks and introduces the Internet of Intelligent Reflecting Surfaces (IoIRS), a distributed, network-layer framework that treats IRSs as programmable network elements. It proposes a hierarchical architecture with Tx, IRSS, IRSN, and an IRS Server, along with an IPv6-based protocol suite to manage discovery, resource allocation, optimization, and actuation. Key contributions include a detailed workflow for service requests, a multi-objective optimization process, and protocols enabling IPv6-integrated control and modular IRS packet structures. The IoIRS concept is demonstrated through terrestrial and space use cases, highlighting capabilities like virtual LoS, ISAC/WPT support, and OTA-Federated Learning, and it discusses major challenges and future directions for scalable, secure deployment across domains.

Abstract

Intelligent Reflecting Surfaces (IRS) are anticipated to serve as a key cornerstone of future wireless networks, providing an unmatched capability to deterministically shape electromagnetic wave propagation. Despite this potential, most existing research still considers the IRS merely as a standalone physical-layer component, controlled by transmitters. However, as networks grow to encompass a massive number of these surfaces and a massive number of transmitters wishing to use them, this transmitter-centric design encounters substantial challenges. To overcome this challenge, we propose the Internet of IRS (IoIRS), an architecture that reconceives the IRS not just as a passive reflecting surface, but as a connected, hybrid entity functioning across both the physical layer and upper network layers. We present the conceptual framework and a preliminary protocol suite necessary to integrate these surfaces into the higher network layers. We conclude by examining how IoIRS architectures could be applied in practice, as their deployment will be essential for fully realizing the capabilities of future wireless networks.

Figures (3)

• Figure 1: Overview of the proposed IoIRS framework. (a) Illustration of the complexity in future dense heterogeneous networks involving diverse transmitters and radio access technologies. (b) Operational bottlenecks in conventional Transmitter-Centric designs, where uncoordinated access attempts lead to resource contention. (c) The IoIRS hierarchical architecture, comprising an IRS Server, Stations (IRSS), and Nodes (IRSNs). IRSNs are categorized into static nodes (wall-mounted) and mobile nodes (satellite, drone, or vehicle-mounted). (d) The proposed IRSS-Centric design, where IRSS units process service requests to allocate optimal IRSNs, establishing robust Virtual Line-of-Sight (VLoS) links for blocked channels.
• Figure 2: Illustration of the Internet of IRS (IoIRS) framework across terrestrial domains: Left shows how the IoIRS Network functions as a distributed control plane where IRS Stations (IRSS) manage global system updates and the domain specific updates are controlled through the central Server. Middle panel visualizes key Next-Generation terrestrial scenarios supported by IoIRS by showing the operational hierarchy that separates the control logic from the physical link. A Transmitter ($Tx$) issues a request; the IRSS determines the optimal configuration and commands the IRS Nodes (IRSNs) which may be static panels or mobile units (Irs's mounted on top of mobile elements shown by addition within right panel), to direct the channel towards the Receiver ($Rx$). Right panel visualizes the application areas: (A) 6G Networks static and drone-mounted IRSNs restore frequency links obstructed by buildings and forming virtual LoS paths under IRSS direction; (B) Smart Cities integrated metasurfaces via windows and mobile IRSNs provide outdoor-to-indoor coverage enhancement and traffic-aware routing for heterogeneous IoT flows; (C) Autonomous Driving roadside and vehicular IRSNs maintain V2X connectivity during rapid mobility, preventing NLoS blind spots by repositioning mobile IRSNs when directed by the IRSS; (D) Localization multiple IRSNs perform coordinated angular scans, enabling IRS-assisted cooperative positioning in urban areas where GPS signals are insufficient; (E) Agriculture 5.0 field-mounted IRSNs extend low-power rural IoT coverage by forming multi-hop reflective paths.
• Figure 3: Space IoIRS: The left side illustrates potential challenges, while the remaining portion shows the IRS-enabled solution. When a blockage occurs, LoS link becomes unavailable, and the IRS network activates to assist the communication link. If locations of the IRSNs are not suitable, IRSNs are not feasible and they remains inactive. Once sufficient location change realized, the IRS network provides a virtual LoS path for the transmitter, enabling reliable communication with improved SINR at the receiver.