Vincenzo Riccobene

An open framework to enable NetFATE (Network Functions at the edge)

In the last few years, Software Defined Networks (SDN) and Network Functions Virtualization (NFV) have been introduced in the Internet as a new way to design, deploy and manage networking services. Working together, they are able to consolidate and deliver the networking components using standard IT virtualization technologies not only on high-volume servers, but even in the end user premises. In this context, this paper presents the NetFATE architecture, a platform aimed at putting virtual network functions (VNF) at the edge of the network. This platform is based on free and open source software on Provider Equipment (PE) and Customer Premise Equipment (CPE) nodes, so allowing function deployment simplification and management cost reduction. Finally, the paper proposes a case study, consisting in the implementation of two virtual personal firewalls used by two clients moving between two access points located at the edge of the core network.

An analytical tool for performance evaluation of software defined networking services

The rapid evolution of low-cost standard hardware coupled with the diffusion and the wide spread of new paradigms are stimulating Telco providers to explore the possibility of breaking down the ossification of the current Internet. This paves the way for the introduction of new approaches like Software Defined Network (SDN) and Network Function Virtualization (NFV) into the next generation networks to provide their users with software defined networking services. This context paves the way to software defined services, dynamically allocating the network functions over the network nodes. In this paper we propose an analytical approach to support designers in the allocation of virtualized function over the network, taking into account both the functions requested by the traffic flows and the quality of service (QoS) that the network provides to them. The proposed analytical approach is able to account the routing, the processing capacities of the network nodes and the statistical characterization of the flows requesting each virtualization function. This paper follows the direction of analytically modeling a network with NFV capabilities for performance evaluation and design support.

A northbound interface for power management in next generation network devices

Recently, a number of approaches based on dynamic power management techniques have been proposed to reduce the energy consumption of telecommunication networks and devices. They are able to optimize the trade-off between network performance and energy requirements. It is possible to execute and extend these techniques to the whole network, by using local control policies together with energy-aware routing and traffic engineering. However, the lack of a standardized representation of the energy-aware capabilities of heterogeneous networking equipment makes their deployment confusing and impractical. To this aim, we have proposed a novel framework, the green abstraction layer (GAL), whose purpose is to define a multi-layered abstraction interface for the hardware and physical resources, where energy management actions are directly performed. Therefore, the GAL syntax can be exposed to the platform-independent logical representation commonly used in network control protocols. Given the internal architectural complexity and heterogeneity of many network devices, the GAL approach is based on a hierarchical decomposition, where each level provides an abstract and aggregated representation of internal components.

Modeling temperature and dissipation behavior of an open multi-frequency green router

Development of green routers aimed at saving energy when the input traffic is low has the positive side effect of reducing the working temperature of their internal components. This idea can encourage the realization of smaller scale routers, but this process has to be supported by the confidence that temperature remains in a given range. For this reason, the target of this paper is to propose an analytical discrete-time Markov model that helps green router designers to calculate in advance the temperature statistics of a router, for given input traffic statistics and energy saving law applied by the router Governor, which is an entity which decides the router policy to be adopted. At the same time the model evaluates the obtained energy saving gain. The proposed model is applied to a case study to show how it can be used to support the design of the router Governor parameters to achieve the target of maintaining the mean temperature below a given threshold.

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.

An analytical tool to design a router Governor controlling energy consumption and temperature

Reduction of energy consumption in the current Internet is one of the main challenges today. For this reason the target of this paper is to propose an analytical tool that allows router manufacturers to design a Governor with the aim of achieving the best trade-off between quality of service and energy saving in respect of a given target on the working temperature.

Design of a Traffic-Aware Governor for Green Routers

Today the reduction of energy consumption in telecommunications networks is one of the main goals to be pursued by manufacturers and researchers. In this context, the paper focuses on routers that achieve energy saving by applying the frequency scaling approach. The target is to propose an analytical model to support designers in choosing the main configuration parameters of the Router Governor in order to meet Quality of Service (QoS) requirements while maximizing energy saving gain. More specifically, the model is used to evaluate the input traffic impacts on the choice of the active router clock frequencies and on the overall green router performance. A case study based on the open NetFPGA reference router is considered to show how the proposed model can be easily applied to a real case scenario.

Exposing energy-aware capabilities in next generation network devices

Dynamic power management techniques have been proposed in a number of recent approaches to reduce the energy consumption of telecommunication networks and devices. These techniques aimed at finding an optimal trade off between network performance and energy requirements. Control policies using energy-aware routing and traffic engineering can be used in order to extend these techniques to the whole network. However, the deployment of the energy-aware capabilities of heterogeneous networking is still unsystematic and impractical, as a standardized representation is still missing. To overcome such an issue, we introduce a novel framework, the Green Abstraction Layer (GAL), whose goal is to define a multi-layered abstraction interface for the hardware and physical resources. Within the GAL, energy management actions are directly performed. The GAL can be thus exposed to the platform-independent logical representation commonly used in network control protocols. Given the internal architectural complexity and heterogeneity of many network devices, the GAL approach is based on a hierarchical decomposition, where each level provides an abstract and aggregated representation of internal components. The general GAL architecture is currently under consideration for standardization in ETSI.

Design of a Temperature-Constrained Governor to Save Energy in an Open Multi-Frequency Green Router

In the last years a new challenge turned out for both researchers and industries in telecommunications area is represented by green networks. Besides energy saving that is possible to achieve, another positive side effect of this is the reduction of the working temperature of internal components of telecommunications devices (switches, home gateway, routers, etc.). This idea is encouraging the development of routers of reduced dimensions as long as there is the knowledge that the temperature remains in a given range. For this reason the target of this paper is to propose a governor policy that provides the best trade-off between quality of service and energy saving in respect of a given target on the working temperature. More specifically, such a governor is in charge to manage the clock frequency of the Central Processor Unit (CPU) of the green router according to the traffic loading the router, varying the processing engine performance, the working temperature and the power consumption of the hardware at the same time. The proposed policy is then applied to a case study and evaluated by simulation to show how it can be used for the above purposes, and to allow green router designers to control the temperature statistics of a router and design the governor parameters to maintain the mean temperature below a given threshold. Design of a TemperatureConstrained Governor to Save Energy in an Open MultiFrequency Green Router

Designing a governor policy for energy saving and heat control in frequency-scaling green routers

Energy costs for telecommunications networks are mainly due to the consumption of both devices and cooling facilities. For this reason the target of this paper is to propose an analytical discrete-time Markov model that allows green router designers to both evaluate performance of temperature-constrained green routers and design Governor policies to achieve the best trade-off between quality of service and energy saving in respect of a given target on the working temperature. The proposed model is applied to a case study to show how it can be used to the above purposes.