Hard Constant Bandwidth Server: Comprehensive Formulation and Critical Scenarios
The Constant Bandwidth Server (CBS) is one of the most used algorithms for implementing resource reservation upon deadline-based schedulers. Although many CBS variants are available in the literature, no proper formalization has been proposed for the CBS in the context of hard reservations, where it is essential to guarantee a bounded-delay service across applications. Existing formulations are affected by a problem that can expose the system to dangerous deadline misses in the presence of blocking. This paper analyzes such a problem and presents a comprehensive and consistent formulation of the CBS for hard reservation scenarios.