QoS protection: Formulation and experimental analysis of the MPLS case

In this paper a new QoS protection paradigm to extend and enhance current QoS routing is formalized and supported by experiments. Previous QoS routing algorithms considers protection as a secondary aspect and uses QoS routing objectives, such as minimizing resources or request rejection, to route backup paths. This work defines new QoS objectives to route backup paths. QoS protection concept is defined as a function of a set of parameters such as packet loss, restoration time and resource optimization. All these parameters are formalized and empirically demonstrated. QoS protection concept also enables evaluating different protection methods. This work takes advantage of many MPLS features but it can be widely applied in other networks, which also implement the concept of “virtual paths” or LSP. Different applications of the QoS protection are pointed out and an example of an application to develop a backup decision module to select the most suitable MPLS protection method, in different network scenarios, with different traffic classes, is also introduced and supported by different case studies. Keywords—QoS routing, protection, MPLS.