Model-Based Engineering for Certification of Complex Adaptive Network Systems

Certifying a network system S involves the assessment of how good S meets its intended QoS objectives in a backdrop of uncontrolled external environment conditions incident on S. For complex network systems where a reasonably accurate and tractable computational model of S may not be known, hierarchical approaches based on cyber-physical systems (CPS) principles are attractive. Here, a piece-wise linearized simple model of S allows a controller to drive S with test inputs and evaluate the output behavior of S over a limited operating region. With model plug-in and controller algorithm switching, a management entity reasons about the behavior of S under different environment conditions and test inputs, to certify S with high confidence. The paper presents a case study of multi-source video congestion control over a bandwidth-limited network path to illustrate our CPS-based certification method.