Roberto Doriguzzi-Corin

A Datapath-Centric Virtualization Mechanism for OpenFlow Networks

The adoption of a robust and scalable network virtualization framework is a key requirement in order to make the vision of a shareable network infrastructure a reality. To this aim, one of the most suitable approaches is the one which takes advantage of the emerging paradigm of Software-Defined Networking (SDN) and OpenFlow, its de-facto standard. Several virtualization frameworks have been proposed in the last few years, however, they are either based on proxy-based solutions that raises scalability and robustness issues (FlowVisor), or they rely on a simplified view of the data path (generally based on Open vSwitch instances) that have little chances to be adopted in production network settings. This paper presents a novel OpenFlow-based network virtualization mechanism exploiting a recent open-source data path project named extensible Data path Daemon (xDPd), the proposed multi-platform data path is based on a robust distributed virtualization architecture that is able to run on multi-version OpenFlow switch network scenarios, has a minimal overhead from a performance point of view and can be easily ported on several hardware platforms via xDPd libraries.

Empowering network operating systems with memory management techniques

Similarly to computer operating systems which guarantee safe access to memory resources, Network Operating Systems shall grant SDN applications a reliable access to neatly organized flow table resources. This paper presents the architecture for a controller-agnostic Memory Management System and some of its functionalities that aim at improving flow table usage and preventing network misconfigurations. From the implementation perspective, this work discusses the applicability of the proposed system, a strategy to evaluate it and current open challenges.

Demonstrating a Distributed and Version-Agnostic OpenFlow Slicing Mechanism

Several virtualization frameworks have been proposed in the last few years for Software Defined Networks (SDN), however, they are either based on proxy-based solutions that raises scalability and robustness issues (FlowVisor), or they leverage on a simplified view of the data-path (generally based on Open vSwitch instances) that have little chances to be adopted in production network settings. In our demonstration we present preliminary results obtained by deploying and using a novel OpenFlow-based network virtualization mechanism. The mechanism is based on a recently proposed distributed virtualization architecture that is able to run on multi-version OpenFlow scenarios.

An effective swapping mechanism to overcome the memory limitation of SDN devices

Thanks to its 1-cycle lookup performance, the Ternary Content Addressable Memory (TCAM) is considered an essential hardware component for the deployment of high-performance Software-Defined Networks (SDN). Unfortunately, in many network scenarios, TCAMs can quickly fill due to their limited memory size, thus preventing the installation of new flow-rules and leading to inefficient traffic forwarding. This issue has already been addressed in computer programming, where Virtual Memory is offered to applications to mimic a much larger physical memory, by swapping memory pages to disk. In a previous work, we proposed and discussed the architecture of a Memory Management System (MMS) for SDN controllers that, like the analogous process for computer Operating Systems, optimizes the memory usage and prevents anomalies due to lack of memory space. This work proposes a memory swapping mechanism for SDN controllers, a function of the MMS which gives SDN applications the illusion of unlimited memory space in the forwarding devices, without requiring any hardware modification or changes in the control protocol. The paper discusses the memory swapping mechanism design, its implementation and proves its quality using real traffic traces, demonstrating lower TCAM memory utilization and potentially increased network performance in terms of end-to-end throughput. A prototype of the MMS is available for testing as an open source project.

NetIDE: All-in-one framework for next generation, composed SDN applications

Software-Defined Networking (SDN) is bringing DevOps [1] capabilities to current networks, reducing the time-to-market for new services and thereby providing a strong incentive for adoption to Service Providers and Network Operators. However, the current SDN landscape is extremely fragmented, so that different open and closed source controller frameworks such as OpenDaylight [2], Ryu [3], Floodlight [4] or ONOS [5] exist. This jeopardises the gains of introducing SDN, since porting SDN applications from one platform to another is time consuming and requires high effort. As a consequence, SDN users (e.g. network operators) face the danger of vendor (or platform) lock-in: they are confined to applications working for the platform of their choice, or forced to re-implement their solutions when they choose a new platform.

NetIDE: Removing vendor lock-in in SDN

The Software-Defined Networking (SDN) paradigm allows networking hardware to be made “malleable” and remotely manageable by the so-called SDN controllers. However, the current SDN landscape is extremely fragmented. Different open and closed source controller frameworks such as Open-Daylight [1], Ryu [2], Floodlight [3], etc. exist. Porting SDN applications from one such platform to another is practically impossible and so, SDN users like network operators face a situation where they are either confined to applications working for the platform of their choice, or forced to re-implement their solutions every time they encounter a new platform.

Are We Ready to Drive Software-Defined Networks? A Comprehensive Survey on Management Tools and Techniques

In the context of the emergent Software-Defined Networking (SDN) paradigm, the attention is mostly directed to the evolution of control protocols and networking functionalities. However, network professionals also need the right tools to reach the same level—and beyond—of monitoring and control they have in traditional networks. Current SDN tools are developed on an ad hoc basis, for specific SDN frameworks, while production environments demand standard platforms and easy integration. This survey aims to foster the definition of the next generation SDN management framework by providing the readers a thorough overview of existing SDN tools and main research directions.

Reusability of software-defined networking applications: A runtime, multi-controller approach

The Software-Defined Networking (SDN) ecosystem is still characterized by a multitude of different controller platforms, each with its own programming model, execution model, and capabilities. This creates a danger of a controller lock-in for both developers of SDN control applications and operators of SDN networks. Since no single controller platform appears to dominate the ecosystem for the foreseeable future, there is a need for portability of control applications between different platforms. We propose an architecture based on executing multiple instances of different controller platforms concurrently in a network to provide the SDN code the environment it was written for. It is built around a controller-independent network event routing element called Network Engine that provides composition and conflict resolution. Results obtained in realistic scenarios demonstrate the feasibility of the proposed approach, which increases both developer productivity and operational flexibility. A preliminary prototype of the architecture is available for testing as an open source project.

Enriching Intent-based SDN to Ease Customer Service Management in Transport Networks

Intent-based Software-Defined Networking can automate mapping of customer services to transport services. We demonstrate this using a multi-layer orchestrator that provisions a complex customer service over an IP/Optical testbed. OCIS codes: (060.4250) Networks, (060.4258) Networks, network topology

Overcoming the memory limits of network devices in SDN-enabled data centers

In extremely connected and dynamic environments, such as data centers, SDN network devices can be exploited to simplify the management of network provisioning. However, they leverage on TCAMs to implement the flow tables, i.e., on size-limited memories that can be quickly filled up when fine-grained traffic control is required, eventually preventing the installation of new forwarding rules. In this work, we demonstrate how this issue can be mitigated by means of a novel flow rule swapping mechanism. Specifically, we first show the negative effects of a full TCAM on a video streaming service provided by an SDN-enabled data center. Then, we show that our swapping mechanism helps in overcoming the inability to properly access a media content available in the data center, by temporarily moving the least matched flow rules from the TCAM to a larger memory outside the SDN device.