Chiara Lombardo

Fine-Grained Energy-Efficient Consolidation in SDN Networks and Devices

The constant evolution and expansion of the Internet and Internet-related technologies has exposed the limitations of the current networking infrastructures, which are represented by the unsustainable power consumption and low level of scalability. In fact, these infrastructures are still based on the typical, ossified architecture of the TCP/IP paradigm. In order to cope with the Future Internet requirements, recent contributions envisage an evolution towards more programmable and efficient paradigms. In this respect, this paper describes the basic issues, the technical approaches, and the methodologies for the implementation of power management primitives in the context of the emerging Software Defined Networking. In detail, we propose to extend one of the most prominent solutions aimed at increasing networking flexibility, the OpenFlow Protocol, to integrate the energy-aware capabilities offered by the Green Abstraction Layer (GAL). However, the mere introduction of node-level solutions would be of little or no use in the absence of a network-wide management scheme to guarantee inter-operability and effectiveness of the proposed architecture. In this respect, this work also proposes an analytical model for the management of a network with these capabilities. The results will show how our solutions are well suited to provide a scalable and efficient network architecture able to manage the orchestration and consolidation of the available resources.

Evaluating the energy-awareness of future Internet devices

Advanced power management capabilities have been proposed to be included into next-generation green network devices in order to modulate their energy requirements according to the workload. The clear side effect of enabling these new capabilities consists in a performance level reduction of network devices. Starting from some existing benchmarking standards for evaluating energy-efficiency, namely ECR and ATIS-060015, this contribution is devoted to determining a set of parameters, and methodologies that can be applied to correctly and precisely evaluate the tradeoff between energy consumption and network performance. Some experimental results obtained with the proposed indexes and methodologies, as well as a green SW router prototype have been provided.

Dynamic voltage and frequency scaling in parallel network processors

In this paper, we consider energy-aware network devices (e.g. routers, switches, etc.) able to trade their energy consumption for packet forwarding performance by means of DVFS techniques. We focus on state-of-the-art packet processing engines, which generally represent the most energy-starving components of network devices, and which are often composed of a number of parallel pipelines to “divide and conquer” the incoming traffic load. Our goal is to control both the power configuration of pipelines, and the way to distribute traffic flows among them, in order to optimize the trade-off between energy consumption and network performance indexes. With this aim, we propose and analyze a constrained optimization policy, which tries to find the best trade-off between power consumption and packet latency times. In order to deeply understand the impact of such policy, a number of tests have been performed by using real-world traffic traces.

OpenFlow in the Small: A Flexible and Efficient Network Acceleration Framework for Multi-Core Systems

Multi-core processors optimized for networking applications typically combine general-purpose cores with offloading engines to relieve the processor cores of specialized packet processing tasks, such as parsing, classification, and security. Unfortunately, modern embedded operating systems still lack an effective and advanced hardware abstraction to exploit these aspects optimally. Based on these considerations, this paper proposes a novel framework, OpenFlow in the Small (OFiS), specifically designed to provide a flexible hardware abstraction layer for heterogeneous multi-core systems with advanced hardware accelerators for network offloading. OFiS represents such accelerators as standard OpenFlow switches inside the processor, moving the edge of the OpenFlow network management to the computational resources inside the end-boxes. As indicated in the experimental evaluation, OFiS exploits hardware parallelism and consolidates the software tasks at finer granularities.

OpenVolcano: An Open-Source Software Platform for Fog Computing

In order to overcome the cloud service performance limits, the INPUT Project aims to go beyond the typical IaaS-based service models by moving computing and storage capabilities from the datacenters to the edge network, and consequently moving cloud services closer to the end users. This approach, which is compatible with the concept of fog computing, will exploit Network Functions Virtualization (NFV) and Software Defined Networking (SDN) to support personal cloud services in a more scalable and sustainable way and with innovative added-value capabilities. This paper presents OpenVolcano, the open-source software platform under development in the INPUT Project, which will realize the fog computing paradigm by exploiting in-network programmability capabilities for off-loading, virtualization and monitoring.

EE-DROP: An energy-aware router prototype

The increasing energy demands of network and networked device architectures represent a threat to the development of the Future Internet. Aside from environmental concerns and increasing energy costs, multi-core processors will soon be constrained by power consumption, which will eventually slow down the development of new technologies. In order to re-think and re-design wired network equipment and infrastructures towards more energy efficient approaches, the ECONET project aims at extending next generation networks, architectures and protocols in the green direction. This paper presents a prototype of one of the 13 platforms developed inside the project, namely the Distributed Router Open Platform (DROP). Results will show how the aggregation of multiple devices with green capabilities can guarantee a satisfying performance level while allowing huge energy savings.

Green extension of OpenFlow

Todays network architectures are not able to cope with the Future Internet requirements, as they are too inefficient, power hungry, and ossified on the TCP/IP paradigm. In order to promote a viable evolution towards new protocols and paradigms, modern network routers should become programmable to allow a flexible management of both traffic flows and power states. In this respect, Software Defined Networking (SDN) can represent the perfect support for the allocation of traffic flows and, at the same time, the management of the power states of the single nodes. To this purpose, this paper proposes to use the Green ion Layer (GAL) to integrate the exchange of power management data among network elements and the application of control strategies inside the SDN paradigm. Moreover, in order to clarify how our study would help overcoming scalability issues and promote energy efficiency at the same time, this paper defines and solves a consolidation problem where the network is described in terms of allocation of packet handling resources and power states.

The dark side of network functions virtualization: A perspective on the technological sustainability

The Network Functions Virtualization (NFV) paradigm is undoubtedly a key technological advancement in the Information and Communication Technology (ICT) community, especially for the upcoming 5G network design. While most of its promise is quite straightforward, the implied reduction of the power consumption/carbon footprint is still debatable, and not in line with the energy efficiency perspective forecasted by the ETSI NFV working group (WG). In this paper, we provide an estimate of the possible future requirements of this upcoming technology when deployed according to the virtual Evolved Packet Core (vEPC) use case specified by the ETSI NFV WG. Our estimation is based on real performance levels, certified by independent third-party laboratories, and datasheet values provided by existing commercial products for both the legacy and NFV network architectures, under different deployment scenarios. Obtained results show that a massive deployment of the current NFV technologies in the EPC may lead to a minimum increase of 106 % in the carbon footprint/energy consumption with respect to the Business As Usual (BAU) network solutions. Moreover, these values tend to increase at a very high pace when the most suitable software/hardware combination is not applied, or when packet processing latency is taken into account.

OpenFlow in the small

Multi-core processors for networking applications typically combine general-purpose cores with off-loading engines, to relieve processor cores of specialized packet processing tasks, such as parsing, classification, and security. Unfortunately, modern embedded operating systems still lack of an effective support and hardware abstraction for optimally exploiting the above mentioned aspects. Starting from these considerations, this paper proposes a novel framework, “OpenFlow in the Small” (OFiS), specifically designed to provide a flexible hardware abstraction for a wide set of heterogeneous multi-core processors with advanced network off-loading capabilities. The OFiS framework allows SW services/applications, or only the operating system, activating and customizing off-loading operations, and distributing them to processor cores on a per-flow basis.

An SDN/NFV Platform for Personal Cloud Services

In the last few years, network “softwarization” is gaining increasing popularity to achieve dynamicity and flexibility. Cloud computing, as well as the new paradigms of software defined networking (SDN) and network functions virtualization (NFV), are supporting this evolution. However, the need to move services closer to users to guarantee low latency in the service fruition on one hand, and the trend to support personalization of services on the other, are stimulating the migration of services toward edge nodes (in the so-called “fog computing” fashion). This is the target of the INPUT platform, proposed in the INPUT project to support future Internet personal cloud services in a more scalable and sustainable way, and with innovative added-value capabilities. The INPUT platform enables next-generation cloud applications to go beyond classical service models, and even replaces physical smart devices, usually placed in users’ homes (e.g., set-top-boxes, etc.), with virtual entities, providing them to users “as a Service.” In this paper, we present the INPUT paradigm and discuss a relevant use case—namely, the virtual set-top-box—adopted to prove the feasibility of the softwarized SDN/NFV paradigm jointly with the fog-computing approach for the support of personal cloud services. The INPUT platform is also compared with a legacy approach to evaluate the gain in terms of quality of experience for both static and mobile users.