GNPy is an open source project of the Telecom Infra Project (TIP). It aims at the development of a software library for the abstraction of physical layer data transport, implemented as wavelength division multiplexing (WDM) through open-source code and open APIs, with the purpose of automatizing disaggregated, multi-vendor open optical networks. We first introduce the GNPy library of applications and functionalities, then, we present validation of the GNPy core. The quality-of-transmission estimator (QoT-E) enables a quick and accurate prediction of the unique performance metric in WDM data transport of optical networks: the Generalized Signal-to-Noise Ratio (GSNR). The presented validation experiments show an excellent accuracy in predicting the GSNR compared to the values obtained experimentally. Finally, we present the GNPy integration with the ONOS network OS in a multi-vendor scenario including open reconfigurable add drop multiplexers (ROADMs) and the related validation experiment.

We propose a framework to manage the link lifetime in an IP backbone network by exploiting the sleep mode (SM). In particular, when an SM feature is available, two different effects coexist: during the SM state, the lifetime tends to be increased and however, when the link changes its power state (from SM to full power or vice-versa), the lifetime tends to be decreased. We, therefore, define an optimal formulation of the lifetime-aware network problem. Moreover, we propose a heuristic, called Acceleration Factor Algorithm, to practically manage the device lifetime. We solve the problem both optimally and with our heuristic, considering two representative case studies. Results show that our approach outperforms the previous energy-aware algorithms, which instead do not consider the lifetime decrease triggered by the power state change. Thus, we argue that a lifetime-aware network management should be pursued when deciding to set an SM state for each device in an Internet Service Provider network.

We study the problem of reducing power consumption in an Internet Service Provider (ISP) network by designing the content distribution infrastructure managed by the operator. We propose an algorithm to optimally decide where to cache the content inside the ISP network. We evaluate our solution over two case studies driven by operators feedback. Results show that the energy-efficient design of the content infrastructure brings substantial savings, both in terms of energy and in terms of bandwidth required at the peering point of the operator. Moreover, we study the impact of the content characteristics and the power consumption models. Finally, we derive some insights for the design of future energy-aware networks.

The problem of reducing power consumption in backbone networks by adopting sleep modes has been extensively studied in the literature. In contrast to previous work, we forecast power consumption and traffic in two operator networks (France Telecom (FT) and Telefo´nica Investigacio´n y Desarrollo (TID)) for the year 2020, and consider both Single Line Rates (SLRs) and Mixed Line Rates (MLRs) deployments. Given these realistic scenarios, the set of devices in sleep mode is computed autonomously on each network node by a simple power-aware algorithm using only local information as input and requiring no rerouting. Results show that the savings obtained by adopting sleep modes are significant, even if power efficiency (W/Gbps) is increased. Moreover, we show that networks using MLR always consume less energy than SLR-based networks when the power-aware algorithm is applied to the considered scenarios.

The energy consumption of network devices, and, as a consequence, of communication networks, is generally independent from their level of utilization, which results in a waste of energy when the network is lightly loaded. Ideally the consumption of a network should be proportional to the amount of traffic it conveys. The most straightforward way to enforce such a proportionality between the network energy consumption and its utilization level, is to dynamically adapt the status of network devices to the load, forcing a subset of them to enter a sleep state during the low activity periods. We present in this paper an algorithm to dynamically put links into a sleep state, based on a cooperative-game approach, named “L-Game”. Our approach decides which links can be switched off based on a measure of the criticality of each link expressed as its Shapley value. This measure combines topological aspects and traffic conditions. Simulation results on real network scenarios show that our solution achieves a better trade off between energy saving and Traffic Engineering than other legacy approaches.

One of the important objectives of every telecommunication operator, when designing an optical network, is to provide a satisfying quality of service in the most cost-effective way to the final customer. As every network is frequently exposed to many different threats causing network disruptions, network recovery is the prime capability needed to achieve this objective. After a brief introduction on the existing reactive recovery methods we present a new method of proactive detection and explain how the method can be applied to some recovery schemes and discuss its benefits.