BITEX: A Cross-Layer Bandwidth Trading System for eXtended Reality Applications

Extended Reality (XR) applications challenge network capabilities owing to their demanding requirements of high bandwidth, ultra-low latency, and reliable delivery. These applications generate heterogeneous traffic patterns, including time-sensitive control data, bandwidth-intensive video streams, and consistent audio streams, each with distinct QoS requirements. Current approaches fail to handle multiple streams with diverse QoS requirements, resulting in performance degradation under varying traffic conditions. We propose BITEX (BandWidth Trading for Extended Reality), a cross-layer enhancement mechanism for TCP BBR that intelligently manages bandwidth allocation across traffic classes using a state-based trading system. In addition, BITEXv2, which implements both data rate adjustment and TCP rate control, achieves better performance with improved fairness metrics. This cross-layer design combines transport-layer modifications with application-layer bandwidth trading through a bidirectional feedback loop, effectively addressing the fundamental limitations of single-layer solutions and enabling the reliable deployment of XR applications in dynamic network environments. Performance evaluation across AR, VR, and CG (cloud gaming) scenarios demonstrate that our proposed method outperforms standard TCP BBR in delay, packet loss, throughput stability, and QoE metrics under varying user loads.