Corrado Rametta

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 SDN/NFV telco operator platform for video broadcasting

In the last few years, SDN and NFV have introduced a new way to design, deploy, and manage networking and application services in telecommunications networks. In this context, this article presents an SDN/NFV-based platform for telco operators who intend to enter the market of video broadcasting service providers. The proposed platform allows telco operators to achieve deployment simplification and management cost reduction to support big/small live streaming content providers, and even unusual video broadcasters, in transmitting video flows to a number of interested users that can be either fixed or mobile, without the need to adopt a dedicated and expensive data delivery infrastructure. The design of the architecture proposed in this article is the result of a cooperative work realized by Telecom Italia, the University of Catania, and Wave Joint Open Lab (JOL), representing three of the most important roles in the evolution process of telecommunications networks toward network softwarization, that is, telco operator, academia, and research lab. Besides an operational and functional description of the proposed architecture, the article discusses implementation aspects of the platform, by introducing a proof of concept that has been realized on the JOLNet platform, a nationwide Italian SDN experimental network developed by Telecom Italia to interconnect its JOL labs with a large-scale geographical facility, with the aim of carrying on research and experimentations on SDN technologies and applications.

A new adaptive receiver-initiated scheme for mitigating starvation in wireless networks

Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) has been adopted by the IEEE 802.11 standard and provides good performance when all transmitters are within the range of each other. Unfortunately, in multi-hop topologies, the asymmetric view of the channel state leads to a throughput distribution where a few flows may capture all the available bandwidth while many other flows get very low throughput and sometime meet starvation. To address this problem, in this paper we describe a solution called Carrier Sense Multiple Access with Collision Avoidance by Receiver Detection (CSMA/CARD) which makes use of collisions sensed by a receiver at the physical layer to help the handshake mechanism and mitigate the effect of such problem. More specifically, we propose a mechanism based on historical observations, where collisions can be used by the receiver to predict whether some sender attempted to initiate a transmission. The receiver then reacts accordingly by participating itself in a handshake sequence. We show some interesting results, obtained through analysis and simulations, when the CSMA/CARD is compared to the IEEE 802.11 protocol.

Dual stream transmission to improve mobile VoIP services over HSPA: A practical test bed

As we already know, perceived speech quality of mobile VoIP applications depends on the individual telephone operator where the radio link is not always reliable for the entire duration of a conversation. Moreover, the quality of voice traffic over IP is greatly reduced due to the strong current limitations in terms of requirements regarding delay and guaranteed bandwidth. In particular, the scope of the paper is to present the architecture and the performance evaluation of a dual stream approach to mobile VoIP applications. Test results, obtained via practical test bed, in which a duplicate copy of a voice packet is sent using two different HSPA operators, present an average packet loss reduction of 60% and an average improvement of speech quality of about 0,8 MOS.

Designing a Softwarized Network Deployed on a Fleet of Drones for Rural Zone Monitoring

In the last decade, the differences in the information communication technology (ICT) infrastructures between urban and rural areas have registered a tremendous increase. ICT infrastructures could strongly help rural communities where many operations are time consuming, labor-intensive and expensive due to limited access and large distances to cover. One of the most attractive solutions, which is widely recognized as promising for filling this gap, is the use of drone fleets. In this context, this paper proposes a video monitoring platform as a service (VMPaaS) for wide rural areas not covered by Internet access. The platform is realized with a Software-Defined Network (SDN)/Network Functions Virtualization (NFV)-based flying ad-hoc network (FANET), whose target is providing a flexible and dynamic connectivity backbone, and a set of drones equipped with high-resolution cameras, each transmitting a video stream of a portion of the considered area. After describing the architecture of the proposed platform, service chains to realize the video delivery service are described, and an analytical model is defined to evaluate the computational load of the platform nodes in such a way so as to allow the network orchestrator to decide the backbone drones where running the virtual functions, and the relative resources to be allocated. Numerical analysis is carried out in a case study.

Video Broadcasting Services Over SDN-NFV Enabled Networks

Software Defined Networks (SDN) and Network Functions Virtualization (NFV) have been introduced in the telecommunications engineering 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 making, in such a way, carriers infrastructures more flexible and adaptive in respect to the needs of both end-users and service providers.In this context, this paper presents the architecture and the related prototype of a video broadcasting service tailored for SDN-NVF enabled networks, allowing network and application functions deployment simplification and management cost reduction. In such a way, the proposed solution enables small/medium and unusual content providers to share events with a restricted number of interested users without the need of adopting a dedicated and expensive data delivery infrastructure.

A dual streaming approach for speech quality enhancement of VoIP service over 3G networks

As is well known, in a 3G network scenario the quality of voice traffic over IP is greatly reduced due to the strong current limitations in terms of requirements regarding delay and guaranteed bandwidth. Moreover, perceived quality of VoIP communications depends on the individual telephone operator where the radio link is not always reliable for the entire duration of a conversation. In particular, the study concerns the effect of packet loss and the degree of improvement in the perceived quality which can be obtained by sending a duplicate copy of a voice packet through two different operators. In terms of perceived speech quality this approach leads to a significant improvement which stands between 0.5 and 1.5 MOS.

Opportunistic P2P communications in delay-tolerant rural scenarios

Opportunistic networking represents a promising paradigm for support of communications, specifically in infrastructureless scenarios such as remote areas communications. In principle in opportunistic environments, we would like to make available all the applications thought for traditional wired and wireless networks like file-sharing and content distribution. In this paper, we present a delay-tolerant scenario for file sharing applications in rural areas, where an opportunistic approach is exploited. In order to support communications, we compare two peer-to-peer (P2P) schemes initially conceived for wireless networks and prove their applicability and usefulness to a DTN scenario, where replication of resources can be used to improve the lookup performance and the network can be occasionally connected by means of a data mule. Simulation results show the suitability of the schemes and allow to derive interesting design guidelines on the convenience and applicability of such approaches.

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.

HSDPA dual streaming approach for improving VoIP speech quality in forensic applications

Today, the mobile HD-VoIP (High Definition Voice over IP) transmission represents one of the most appropriate communication techniques for the environmental wiretap applications. The perceived speech quality, which is the crucial aspect of a forensic scenario, depends on the QoS guaranteed by the wireless data service of a specific telephone operator and it is mainly due to the radio link quality, packet delay/loss, and guaranteed bandwidth. In particular, the paper presents the architecture and the performance evaluation of a dual stream approach to mobile VoIP applications (DualVoIP) over 3G/HSPA access networks. Test results, obtained via a real-time implementation of DualVoIP algorithms adopted in a practical test bed, demonstrate an average packet loss reduction of 85% and an average improvement of speech quality of about 0,8 MOS. Finally, the paper highlights the significant reduction of the audio signal clipping at all levels: phoneme, word, sentence and conversation.