Nicola Ciulli

All-optical packet/circuit switching-based data center network for enhanced scalability, latency, and throughput

Applications running inside data centers are enabled through the cooperation of thousands of servers arranged in racks and interconnected together through the data center network. Current DCN architectures based on electronic devices are neither scalable to face the massive growth of DCs, nor flexible enough to efficiently and cost-effectively support highly dynamic application traffic profiles. The FP7 European Project LIGHTNESS foresees extending the capabilities of todays electrical DCNs throPugh the introduction of optical packet switching and optical circuit switching paradigms, realizing together an advanced and highly scalable DCN architecture for ultra-high-bandwidth and low-latency server-to-server interconnection. This article reviews the current DC and high-performance computing (HPC) outlooks, followed by an analysis of the main requirements for future DCs and HPC platforms. As the key contribution of the article, the LIGHTNESS DCN solution is presented, deeply elaborating on the envisioned DCN data plane technologies, as well as on the unified SDN-enabled control plane architectural solution that will empower OPS and OCS transmission technologies with superior flexibility, manageability, and customizability.

Energy Efficiency in integrated IT and optical network infrastructures: The GEYSERS approach

In this paper we propose energy efficient design and operation of infrastructures incorporating integrated optical network and IT resources. For the first time we quantify significant energy savings of a complete solution jointly optimizing the allocation and provisioning of both network and IT resources. Our approach involves virtualization of the infrastructure resources and it is proposed and developed in the framework of the European project GEYSERS - Generalised Architecture for Dynamic Infrastructure Services.

Phosphorus grid-enabled GMPLS control plane (G MPLS): architectures, services, and interfaces

G2MPLS is a network control plane architecture that implements the concept of grid network services. In the framework of the 1ST Phosphorus project, GNS allows the provisioning of network and grid resources in a single step through a set of seamlessly integrated procedures. The implementation of GNS imposes a number of requirements in the control planes of the underlying network infrastructure. This article describes services such as GNS set up and restoration, GNS resource and service discovery, and advance reservation services, which are the main trigger factors of the G2MPLS control plane architectures. The article provides an overview of overlay architecture prior to turning to the main focus of the article, which is the integrated architecture through service procedures and the grid-enabled network interfaces provided by the Phosphorus project.

Intercloud Architecture Framework for Heterogeneous Cloud Based Infrastructure Services Provisioning On-Demand

This paper presents on-going research to develop the Intercloud Architecture Framework (ICAF) that addresses problems in multi-provider multi-domain heterogeneous cloud based infrastructure services and applications integration and interoperability, to allow their on-demand provisioning. The paper refers to existing standards and ongoing standardisation activity in Cloud Computing, in particular, recently published NIST Cloud Computing Reference Architecture (CCRA) and ITU-T JCA-Cloud activity. The proposed ICAF defines four complementary components addressing Intercloud integration and interoperability: multi-layer Cloud Services Model that combines commonly adopted cloud service models, such as IaaS, PaaS, SaaS, in one multilayer model with corresponding inter-layer interfaces, Intercloud Control and Management Plane that supports cloud based applications interaction, Intercloud Federation Framework, and Intercloud Operations Framework. The paper briefly describes the Service delivery and lifecycle management as an important ICAF component that provides a basis for consistent management and security of the provisioned on-demand complex cloud based services. The paper describes an implementation of the Intercloud Control and Management Plane in the GEYSERS project to allow optimal provisioning of the combined Network+IT resources in the inter-cloud environment. The proposed architecture is intended to provide an architectural model for developing Intercloud middleware and in this way will facilitate clouds interoperability and integration.

SDN-enabled OPS with QoS guarantee for reconfigurable virtual data center networks

Optical packet switching (OPS) can enhance the performance of data center networks (DCNs)by providing fast and large-capacity switching capability. Benefiting from the software-defined networking (SDN) control plane, which could update the look-up-table (LUT) of the OPS, virtual DCNs can be flexibly created and reconfigured. In this work, we have implemented and assessed an SDN-based control framework for an OPS node, where the OpenFlow protocol has been extended in support of the OPS switching paradigm. Application flows are switched by the OPS at submicrosecond hardware speed, decoupled from the slower (millisecond timescale) SDN control operation. By the DCN infrastructure provider, the virtual networks become directly programmable with the abstraction of the underlying OPS node. Experimental results validate the successful setup of virtual network slices for intra-data center interconnect and quality of service (QoS) guarantee for high-priority application flows. Data plane resources are efficiently shared by exploiting statistical multiplexing. In addition, the capability of exposing per-port OPS traffic statistics information to the SDN controller enables the implementation and experimental validation of load balancing algorithms to improve the QoS performance.

Multi-Tenant Software-Defined Hybrid Optical Switched Data Centre

We introduce a holistic solution for software-defined optical data centres (DC). Hybrid optical circuit/packet switching technologies are employed in the data plane, while a software-defined networking (SDN) controller based on OpenDaylight with significant extensions is adopted for the data centre network (DCN) control and management. Novel functional modules in the SDN controller together with its northbound (NBI) and southbound interfaces (SBI) are designed and developed. The OpenFlow protocol is extended at the SBI to support communication between the extended OpenDaylight SDN controller and the optical DCN devices. Over the NBIs, DC applications and the cloud management system directly interact with the optical DCN. A virtual data centre (VDC) application is designed and developed that dynamically creates and provisions multiple coexisting but isolated VDCs. An optical network-aware virtual machine (VM) placement method is proposed and implemented for a single-step deployment of both network and IT (VM) resources to accommodate the VDC requests. The VDC deployment process is extensively simulated and experimentally demonstrated.

Planning of dynamic virtual optical cloud infrastructures: The GEYSERS approach

This article focuses on planning and replanning of virtual infrastructures over optical cloud infrastructures comprising integrated optical network and IT resources. This concept has been developed in the context of the European project GEYSERS. GEYSERS has proposed a novel multi-layer architecture, described in detail, that employs optical networking capable of provisioning optical network and IT resources for end-to-end cloud service delivery. The procedures required to perform virtual infrastructure planning and replanning at the different architecture layers are also detailed. An optimization scheme suitable to dynamically plan and replan virtual infrastructures is presented and compared to conventional approaches, and the benefits of dynamic replanning are discussed and quantified. The final project demonstration, focusing on planning, replanning, and dynamically establishing virtual infrastructures over the physical resources, is presented, while some emulation results are provided to further evaluate the performance of the GEYSERS solution.

Bringing optical networks to the cloud: an architecture for a sustainable future internet

Over the years, the Internet has become a central tool for society. The extent of its growth and usage raises critical issues associated with its design principles that need to be addressed before it reaches its limits. Many emerging applications have increasing requirements in terms of bandwidth, QoS and manageability. Moreover, applications such as Cloud computing and 3D-video streaming require optimization and combined provisioning of different infrastructure resources and services that include both network and IT resources. Demands become more and more sporadic and variable, making dynamic provisioning highly needed. As a huge energy consumer, the Internet also needs to be energyconscious. Applications critical for society and business (e.g., health, finance) or for real-time communication demand a highly reliable, robust and secure Internet. Finally, the future Internet needs to support sustainable business models, in order to drive innovation, competition, and research. Combining optical network technology with Cloud technology is key to addressing the future Internet/Cloud challenges. In this context, we propose an integrated approach: realizing the convergence of the IT- and optical-network-provisioning models will help bring revenues to all the actors involved in the value chain. Premium advanced network and IT managed services integrated with the vanilla Internet will ensure a sustainable future Internet/Cloud enabling demanding and ubiquitous applications to coexist.

Energy efficiency considerations in integrated IT and optical network resilient infrastructures

The European Integrated Project GEYSERS - Generalised Architecture for Dynamic Infrastructure Services - is concentrating on infrastructures incorporating integrated optical network and IT resources in support of the Future Internet with special emphasis on cloud computing. More specifically GEYSERS proposes the concept of Virtual Infrastructures over one or more interconnected Physical Infrastructures comprising both network and IT resources. Taking into consideration the energy consumption levels associated with the ICT today and the expansion of the Internet in size and complexity, that incurring increased energy consumption of both IT and network resources, energy efficient infrastructure design becomes critical. To address this need, in the framework of GEYSERS, we propose energy efficient design of infrastructures incorporating integrated optical network and IT resources, supporting resilient end-to-end services. Our modeling results quantify significant energy savings of the proposed solution by jointly optimizing the allocation of both network and IT resources.

Architectural approaches for the integration of the service plane and control plane in optical networks

This paper presents some instantiations of novel application-aware network architectures for emerging IT services and future Internet applications. It proposes and analyses network architectures where the Control and Service Planes are closely and seamlessly interacting with the applications. One instantiation, the Grid-GMPLS (G^2MPLS, as defined by the Phosphorus project) is presented, which implements the Network Control Plane (NCP) architecture for the support of Grid Network Services (GNS). The GNS allows the provisioning of network and HPC/Grid resources in a single-step through a set of seamlessly integrated procedures. In a second example of instantiation, a quite popular application in signalling, i.e. the Session Initiation Protocol (SIP), is integrated with the Optical Burst Switched (OBS) network technology. The SIP-enabled OBS network can be used to manage application sessions and provide network and IT services according to application requirements. This paper investigates the requirements that these new integrated architectures impose on supporting network Control and Service Planes, and technologies, and discusses their possible implementations.