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A multidomain optical transport network composed of heterogeneous optical transport technologies (e.g., flexi/fixedgrid optical circuit switching and optical packet switching) and control plane technologies (e.g., centralized OpenFlow or distributed GMPLS) does not naturally interoperate, and a network orchestration mechanism is required. A network orchestrator allows the composition of end-to-end network service provisioning across multidomain optical networks comprising different transport and control plane technologies. Software-defined networking (SDN) is a key technology to address this requirement, since the separation of control and data planes makes the SDN a suitable candidate for end-to-end provisioning service orchestration across multiple domains with heterogeneous control and transport tech- nologies. This paper presents two different network orchestration's architectures based on the application-based network operations (ABNO) which is being defined by IETF based on standard building blocks. Then, we experimentally assesses in the international testbed of the STRAUSS project, an ABNO-based network orchestrator for end-to-end multi-layer (OPS and Flexi-grid OCS) and multidomain provisioning across heterogeneous control domains (SDN/OpenFlow and GMPLS/Stateful PCE) employing dynamic domain abstraction based on virtual node aggregation.Index Terms-Control plane, flexi-grid optical networks, generalized multiprotocol label switching (GMPLS), openFlow, path Manuscript

To overcome the Internet ossification, network virtualization has been proposed as a promising method because of its advantages (e.g., on demand and efficient resource allocation). Virtual network embedding (VNE) is one of the main challenges for network virtualization. Energy costs of servers in data centers (DCs) are major contribution to power consumption in information and communication technology (ICT). Therefore, VNE should consider both acceptance ratio and power consumption. In this paper, a mixed integer linear programming (MILP) model is proposed with the objective of minimizing the total power consumption in software defined optical data center networks (SD-ODCNs) by reducing the active data centers and power-consuming network components. In addition, the coordinates of nodes and delay of links are considered for more realistic scenario. Comparing with existing node ranking method, proposed global topology resource (GTR) can effectively evaluate the possibility of each DC node to host virtual nodes. Based on GTR method, we propose location aware energy efficient VNE algorithm, namely GTR-VNE. Simulation results show that GTR-VNE can obtain up to 9.3% and 5% improvement of power consumption and acceptance ratio compared with benchmarks. Furthermore, based on GTR and artificial intelligence ant colony optimization (ACO), another energy efficient algorithm ACO-VNE is proposed. ACO-VNE can obtain up to 28.7% improvement on power consumption compared with GTR-VNE. In addition, ACO-VNE has better performance in terms of revenue cost ratio and acceptance ratio.

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In Spectrum-Sliced Elastic Optical Path Networks (SLICE), the lightpath bandwidth is variable and the virtual topology overlay on a physical topology shall be designed to optimize the spectrum utilization. Under static traffic, SLICE networks are typically designed through a Mixed Integer Linear Programming (MILP) with the aim of minimizing the spectrum utilization. In this paper, a new MILP formulation for protection in SLICE networks is proposed, which uses the concept of bandwidth squeezing and grooming to guarantee a minimum agreed bandwidth for each source-destination pair in the surviving bandwidth. The route for each demand on the physical topology is determined by balance equations together with physical layer constraints in the formulation, so that no pre-calculated routes are required and the modulation format of each established lightpath may be chosen with enough quality of transmission and save network spectrum. Therefore, the proposed formulation jointly solves the virtual topology design and physical topology design problems. The first results evaluate the effectiveness of the MILP formulation for two small networks when connections are under different Service Level Agreement (SLA) requirements and are provisioned by an appropriate protection scheme and different modulation formats. Due to the NP-hard nature of the proposed MILP formulation, a heuristic algorithm for moderately large networks is also proposed. Case studies are carried out in order to analyze the basic properties of the formulation and the performance of the proposed heuristic. With the proposed formulation, it is possible to identify the configurations that ensure minimum spectrum occupation with different kinds of protection for each lightpath. Different kinds of modulation formats are considered and contrasted to the benchmark case of a single modulation format and using the same kind of protection for all lightpaths.

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