DGR: Delay-Guaranteed Routing Protocol

This paper introduces Delay-Guaranteed Routing (DGR), a distributed routing protocol designed to provide network services with guaranteed delay. Traditional methods of ensuring delay guarantees rely on resource reservation or traffic engineering, which face challenges in efficiently utilizing resources in networks with mesh topologies and high dynamism. In contrast, DGR employs priority queue management and per-hop delay bounds to construct a shortest path forest, allowing for exploration of all forwarding directions while maintaining delay guarantees. A randomized back-pressure route selection strategy, utilizing local and neighborhood queue information, ensures load balancing in highly dynamic networks. Extensive simulations demonstrate the effectiveness of DGR in providing delay-guaranteed services, managing congestion and link failures, and coexisting harmoniously with existing routing protocols for non-time-sensitive services.