Journal article Open Access
Francesco Paolucci; Filippo Cugini; Gabriele Cecchetti; Piero Castoldi
Traffic engineering (TE) solutions are enabled by the adoption of the path computation element (PCE) architecture. Cooperative inter-PCE communications, in combination with TE information export mechanisms, such as the link state extensions to BGP protocol (BGP-LS) enable TE in heterogeneous networks scenarios with different layers, domains, and technologies. Multilayer networks, such as IP/MPLS over elastic optical networks are a typical example of such scenarios. However, these currently adopted export mechanisms are conceived for limited amount of exchanged information in order to preserve scalability, especially if centralized entities are considered, such as PCEs and controllers. Moreover, some information (e.g., router interfaces and transceiver card association) are not always available at the control plane level. Thus, so far limited deployment of interlayer TE procedures has been experienced. In this paper, we propose a novel network element called open network database. Exploiting the state-of-the-art of database platforms while assuring high scalability and reliability performance, dedicated control and management applications run complex reoptimization procedures with a set of ad hoc queries without relying on complex control infrastructure or without overloading the orchestrators, thus simplifying the implementation of network applications and achieving advanced TE. A YANG-based database for interconnected TE networks is proposed and implemented to enable dedicated applications to perform complex multidomain/layer operations. The database is successfully utilized for effective and extremely scalable maintenance applications in multilayer networks.