Resource Allocation and Optimization for 6G Wireless Networks: Requirements, Design Principles, and Open Challenges

Resource allocation plays a crucial role in determining the overall performance of 6G wireless networks; however, the growing number of users and the integration of heterogeneous infrastructures make this task increasingly challenging. Even with higher capacity and wider coverage, spectrum and energy resources remain limited. Furthermore, different network infrastructures operate under rapidly changing wireless conditions. Therefore, achieving the expected 6G network performance also depends on allocating these limited resources based on current network conditions. This requirement has led to the development of various optimization methods for wireless-resource allocation. However, the performance improvements reported in existing studies do not necessarily establish whether the corresponding methods can operate under 6G networks. Most evaluations emphasize the resulting allocation quality while providing limited evidence on whether the complete decision process remains efficient under changing network conditions. This paper therefore evaluates the operational evidence reported for centralized, distributed, and hybrid resource allocation against criteria derived from 6G requirements. The assessment of several state-of-the-art solutions shows that solution quality is consistently demonstrated; however, evidence concerning decision timeliness, signaling overhead, and resource-management energy remains limited. Based on these findings, the paper derives four operational design principles: validity-aware control, efficient coordination, feasibility-preserving adaptation, and net-benefit management. Accordingly, it identifies open challenges for practical 6G resource allocation.